ATL: Tropical Storm BERTHA advisories

[cycloneye]

316
WTNT22 KNHC 061443
TCMAT2
TROPICAL STORM BERTHA FORECAST/ADVISORY NUMBER 14
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1500 UTC SUN JUL 06 2008

TROPICAL STORM CENTER LOCATED NEAR 17.4N 45.1W AT 06/1500Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 18 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1000 MB
MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT.
34 KT....... 75NE 30SE 0SW 75NW.
12 FT SEAS..240NE 90SE 60SW 180NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 17.4N 45.1W AT 06/1500Z
AT 06/1200Z CENTER WAS LOCATED NEAR 17.2N 44.2W

FORECAST VALID 07/0000Z 18.0N 47.8W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 30NE 0SE 0SW 30NW.
34 KT... 90NE 45SE 30SW 90NW.

FORECAST VALID 07/1200Z 18.9N 50.9W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 30NE 0SE 0SW 30NW.
34 KT... 90NE 45SE 30SW 90NW.

FORECAST VALID 08/0000Z 19.7N 53.5W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 45SW 100NW.

FORECAST VALID 08/1200Z 20.5N 56.0W
MAX WIND 65 KT...GUSTS 80 KT.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 45SW 100NW.

FORECAST VALID 09/1200Z 22.5N 60.5W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 60NE 35SE 25SW 50NW.
34 KT...120NE 75SE 50SW 100NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 10/1200Z 25.0N 64.0W
MAX WIND 70 KT...GUSTS 85 KT.

OUTLOOK VALID 11/1200Z 27.0N 66.5W
MAX WIND 70 KT...GUSTS 85 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.4N 45.1W

NEXT ADVISORY AT 06/2100Z

$$
FORECASTER BROWN

WTNT32 KNHC 061444
TCPAT2
BULLETIN
TROPICAL STORM BERTHA ADVISORY NUMBER 14
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM AST SUN JUL 06 2008

...BERTHA MOVING BRISKLY WESTWARD AND FORECAST TO STRENGTHEN...

AT 1100 AM AST...1500Z...THE CENTER OF TROPICAL STORM BERTHA WAS
LOCATED NEAR LATITUDE 17.4 NORTH...LONGITUDE 45.1 WEST OR ABOUT 1185
MILES...1905 KM...EAST OF THE NORTHERN LEEWARD ISLANDS.

BERTHA IS MOVING TOWARD THE WEST NEAR 21 MPH...33 KM/HR. A GENERAL
WEST-NORTHWESTWARD MOTION WITH A GRADUAL DECREASE IN FORWARD SPEED
IS EXPECTED DURING THE NEXT COUPLE OF DAYS...AS BERTHA REMAINS OVER
THE WATERS OF THE CENTRAL TROPICAL ATLANTIC. IT IS MUCH TOO EARLY
TO DETERMINE IF BERTHA WILL EVENTUALLY AFFECT ANY LAND AREAS.

MAXIMUM SUSTAINED WINDS ARE NEAR 50 MPH...85 KM/HR...WITH HIGHER
GUSTS. GRADUAL STRENGTHENING IS FORECAST DURING THE NEXT COUPLE OF
DAYS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 85 MILES...140 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1000 MB...29.53 INCHES.

REPEATING THE 1100 AM AST POSITION...17.4 N...45.1 W. MOVEMENT
TOWARD...WEST NEAR 21 MPH. MAXIMUM SUSTAINED WINDS...50 MPH.
MINIMUM CENTRAL PRESSURE...1000 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM AST.

$$
FORECASTER BROWN


WTNT42 KNHC 061446
TCDAT2
TROPICAL STORM BERTHA DISCUSSION NUMBER 14
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM EDT SUN JUL 06 2008

A SERIES OF MICROWAVE OVERPASSES THIS MORNING SHOW THAT BERTHA HAS
CHANGED LITTLE IN ORGANIZATION DURING THE PAST 24 HOURS. QUIKSCAT
DATA FROM 0852 UTC INDICATE THAT THE MAXIMUM WINDS REMAIN ABOUT 45
KT...WHICH AGREES WITH THE LATEST DVORAK INTENSITY ESTIMATES.
HOWEVER...RECENT VISIBLE SATELLITE IMAGES REVEAL AN INCREASE IN
CONVECTION WHICH MAY FORETELL AN INCREASE IN STRENGTH. SSTS UNDER
BERTHA HAVE INCREASED TO AROUND 26 CELSIUS AND ARE EXPECTED TO WARM
A COUPLE OF DEGREES DURING THE NEXT 2 DAYS. SHEAR IS FORECAST TO
REMAIN LOW...SO GRADUAL STRENGTHENING IS EXPECTED DURING THE NEXT
48 HOURS AND BERTHA COULD BECOME A HURRICANE DURING THAT TIME.
LATER IN THE FORECAST PERIOD...IT IS DIFFICULT TO DETERMINE EXACTLY
WHAT EFFECT AN UPPER-LEVEL TROUGH OVER THE WESTERN ATLANTIC WILL
HAVE ON THE CYCLONE. IF IT REMAINS IN PLACE...THE TROUGH WOULD
PRODUCE AN INCREASE IN SOUTHWESTERLY SHEAR. SOME OF THE GLOBAL
MODELS SUGGEST A WEAKENING OF THE TROUGH HOWEVER...WHICH WOULD KEEP
BERTHA IN A MORE FAVORABLE ENVIRONMENT. DUE TO THESE UNCERTAINTIES
THE INTENSITY FORECAST BEYOND 3 DAYS KEEPS BERTHA AT THE SAME
STRENGTH.

BERTHA CONTINUES MOVING RAPIDLY WESTWARD OR 280/18 KT. A
WEST-NORTHWESTWARD TRACK WITH A REDUCTION IS FORWARD SPEED IS
EXPECTED DURING THE NEXT DAY OR TWO. THERE IS A LITTLE LESS SPREAD
IN THE MODELS THIS MORNING...WITH THE MAJORITY OF THE GUIDANCE
SHOWING A MORE NORTHWESTWARD TURN IN 2-3 DAYS AS THE RIDGE OVER THE
WESTERN ATLANTIC BEGIN TO WEAKEN. THE HWRF CONTINUES TO INSIST ON
THE TURN OCCURRING MUCH SOONER...WHILE THE UKMET REMAINS THE
WESTERNMOST MODEL BUT WITH A WEAKENED TROPICAL CYCLONE OR EVEN AN
OPEN WAVE. THE OFFICIAL TRACK HAS BEEN ADJUSTED EASTWARD...BUT IT
REMAINS LEFT OF MOST OF THE GUIDANCE AND ALSO LEFT OF THE MODEL
CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/1500Z 17.4N 45.1W 45 KT
12HR VT 07/0000Z 18.0N 47.8W 50 KT
24HR VT 07/1200Z 18.9N 50.9W 55 KT
36HR VT 08/0000Z 19.7N 53.5W 60 KT
48HR VT 08/1200Z 20.5N 56.0W 65 KT
72HR VT 09/1200Z 22.5N 60.5W 70 KT
96HR VT 10/1200Z 25.0N 64.0W 70 KT
120HR VT 11/1200Z 27.0N 66.5W 70 KT

$$
FORECASTER BROWN

[cycloneye]

WTNT42 KNHC 062057
TCDAT2
TROPICAL STORM BERTHA DISCUSSION NUMBER 15
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM EDT SUN JUL 06 2008

A COUPLE OF MICROWAVE IMAGES JUST RECEIVED SUGGEST THAT BERTHA'S
VORTEX IS TILTED A LITTLE. THE IMAGES INDICATE THAT THE
LOW-LEVEL CENTER IS LOCATED JUST SOUTHWEST OF THE MID-LEVEL CENTER.
HOWEVER...THESE IMAGES ALSO SUGGEST THAT THE OVERALL STRUCTURE HAS
IMPROVED WITH THE APPEARANCE OF AN EYE FEATURE...SUGGESTING THAT
BERTHA IS STRENGTHENING. DVORAK INTENSITY ESTIMATES WERE 45 KT AT
18Z...BUT WITH THE IMPROVING STRUCTURE THE INITIAL INTENSITY IS
INCREASED TO 50 KT. CONDITIONS APPEAR CONDUCIVE FOR STRENGTHENING
DURING THE NEXT COUPLE OF DAYS AND BERTHA COULD BECOME A HURRICANE.
HOWEVER...INDICATIONS ARE THAT BEYOND 48 HOURS...WESTERLY SHEAR
COULD HALT ANY ADDITIONAL STRENGTHENING AS SUGGESTED BY THE SHIPS
MODELS.

BERTHA IS MOVING WEST-NORTHWESTWARD OR 285/17 KT. ALL OF THE
AVAILABLE GUIDANCE SHOWS A NORTHWEST TURN AS THE RIDGE OVER THE
WESTERN ATLANTIC WEAKENS IN A FEW DAYS. HOWEVER...THERE REMAINS
SOME SPREAD IN THE GUIDANCE AS TO WHEN THE TURN OCCURS. THE HWRF
AND GFDL...WHICH DEPICT A STRONG TROPICAL CYCLONE REMAINS ALONG
THE EASTERN EDGE OF THE MODEL ENVELOPE. THE UKMET WHICH KEEPS
BERTHA WEAKER IS ALONG THE WESTERN EDGE. THE NEW TRACK
FORECAST IS ADJUSTED SLIGHTLY EASTWARD...BUT STILL REMAINS
WEST OF THE MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/2100Z 18.1N 47.0W 50 KT
12HR VT 07/0600Z 18.7N 49.6W 55 KT
24HR VT 07/1800Z 19.5N 52.3W 60 KT
36HR VT 08/0600Z 20.2N 54.6W 65 KT
48HR VT 08/1800Z 20.9N 56.7W 70 KT
72HR VT 09/1800Z 23.0N 60.5W 70 KT
96HR VT 10/1800Z 26.0N 64.0W 70 KT
120HR VT 11/1800Z 29.0N 65.5W 70 KT

$$
FORECASTER BROWN

[cycloneye]

WTNT22 KNHC 070233
TCMAT2
TROPICAL STORM BERTHA FORECAST/ADVISORY NUMBER 16
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
0300 UTC MON JUL 07 2008

TROPICAL STORM CENTER LOCATED NEAR 18.6N 48.9W AT 07/0300Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 17 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 994 MB
MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT.
50 KT....... 30NE 0SE 0SW 30NW.
34 KT....... 75NE 30SE 0SW 75NW.
12 FT SEAS..250NE 180SE 75SW 180NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 18.6N 48.9W AT 07/0300Z
AT 07/0000Z CENTER WAS LOCATED NEAR 18.4N 48.1W

FORECAST VALID 07/1200Z 19.3N 51.5W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 30NE 0SE 0SW 30NW.
34 KT... 90NE 45SE 30SW 90NW.

FORECAST VALID 08/0000Z 20.0N 54.5W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 20NE 0SE 0SW 20NW.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 45SW 100NW.

FORECAST VALID 08/1200Z 21.0N 57.0W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 20NE 0SE 0SW 20NW.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 45SW 100NW.

FORECAST VALID 09/0000Z 22.0N 59.5W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 45SW 100NW.

FORECAST VALID 10/0000Z 24.0N 62.0W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 60NE 35SE 25SW 50NW.
34 KT...120NE 75SE 50SW 100NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 11/0000Z 27.0N 64.5W
MAX WIND 70 KT...GUSTS 85 KT.

OUTLOOK VALID 12/0000Z 30.0N 65.5W
MAX WIND 70 KT...GUSTS 85 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.6N 48.9W

NEXT ADVISORY AT 07/0900Z

$$
FORECASTER AVILA

265
WTNT32 KNHC 070234
TCPAT2
BULLETIN
TROPICAL STORM BERTHA ADVISORY NUMBER 16
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM AST SUN JUL 06 2008

...BERTHA RIGHT ON TRACK...APPEARS TO BE ON ITS WAY TO BECOME A
HURRICANE...

AT 1100 PM AST...0300Z...THE CENTER OF TROPICAL STORM BERTHA WAS
LOCATED NEAR LATITUDE 18.6 NORTH...LONGITUDE 48.9 WEST OR ABOUT 930
MILES...1500 KM...EAST OF THE NORTHERN LEEWARD ISLANDS.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 20 MPH...32 KM/HR.
THIS MOTION IS EXPECTED TO CONTINUE DURING THE NEXT 24 TO 48 HOURS
WITH A GRADUAL DECREASE IN FORWARD SPEED. IT TOO EARLY TO DETERMINE
IF BERTHA EVENTUALLY AFFECT ANY LAND AREAS.

MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 65 MPH...100
KM/HR...WITH HIGHER GUSTS. BERTHA WILL LIKELY BECOME A HURRICANE ON
MONDAY.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 85 MILES...140 KM...
MAINLY TO THE NORTH OF THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 994 MB...29.35 INCHES.

REPEATING THE 1100 PM AST POSITION...18.6 N...48.9 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 20 MPH. MAXIMUM SUSTAINED WINDS...65
MPH. MINIMUM CENTRAL PRESSURE...994 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 AM AST.

$$
FORECASTER AVILA

WTNT42 KNHC 070234
TCDAT2
TROPICAL STORM BERTHA DISCUSSION NUMBER 16
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM EDT SUN JUL 06 2008

THE SATELLITE PRESENTATION HAS GRADUALLY IMPROVED DURING THE PAST
SEVERAL HOURS. THE CONVECTION IS SYMMETRIC ABOUT THE CENTER WHILE
THE OUTFLOW HAS BEEN EXPANDING WESTWARD...TYPICAL OF AN
INTENSIFYING CYCLONE. FURTHERMORE...CONSECUTIVE MICROWAVE DATA SHOW
A WELL DEFINED RING OF DEEP CONVECTION...OR EYE-LIKE FEATURE...
WHICH IS GRADUALLY BECOMING ALIGNED VERTICALLY. THIS COULD
EVENTUALLY BE THE PRECURSOR OF AN EYE FORMATION. DVORAK T-NUMBERS
HAVE INCREASED AND NOW SUPPORT AN INITIAL INTENSITY OF 55 KNOTS.
THE OCEAN IS PLENTY WARM AHEAD OF BERTHA SO THE SHEAR WILL BE THE
MAIN PRIMARY LARGE SCALE FACTOR CONTROLLING THE FUTURE INTENSITY.
WE ARE NOT CONSIDERING EYEWALL CYCLES AT THIS TIME...IN CASE AN EYE
FORMS. BECAUSE THE SHEAR IS EXPECTED TO BE WEAK FOR THE NEXT DAY
OR TWO... STRENGTHENING IS INDICATED AND BERTHA COULD BECOME A
HURRICANE ON MONDAY. THEREAFTER...THE SHEAR IS EXPECTED TO
FLUCTUATE SO NO IMPORTANT CHANGES IN INTENSITY ARE FORECAST.

THE CENTER IS A LITTLE FARTHER NORTH AS IT APPEARS TO BE REALIGNING
WITH THE MID-LEVEL VORTEX. THIS IS NOT A CHANGE IN TRACK SINCE
BERTHA IS STILL MOVING TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT
17 KNOTS. A WEAKNESS OF THE SUBTROPICAL RIDGE ALONG 50 TO 55
DEGREES WEST WILL PROBABLY CAUSE BERTHA TO BEGIN TO SLOW DOWN SOON.
THE SUBTROPICAL RIDGE IS EXPECTED TO REBUILD SOME IN A DAY OR TWO
CAUSING BERTHA TO CONTINUE ON A WEST-NORTHWEST TO NORTHWEST TRACK.
BY THE END OF THE FORECAST PERIOD...THE STEERING CURRENTS ARE
FORECAST TO WEAKEN AGAIN AND BERTHA SHOULD SLOW DOWN CONSIDERABLY
AS INDICATED BY SOME GLOBAL MODELS. THE OFFICIAL FORECAST IS
CONSISTENT WITH MOST OF THE TRACK GUIDANCE WHICH IS IN MUCH BETTER
AGREEMENT TONIGHT. NO NEED TO DISCUSS EVERY MODEL.

FORECAST POSITIONS AND MAX WINDS

INITIAL 07/0300Z 18.6N 48.9W 55 KT
12HR VT 07/1200Z 19.3N 51.5W 60 KT
24HR VT 08/0000Z 20.0N 54.5W 70 KT
36HR VT 08/1200Z 21.0N 57.0W 70 KT
48HR VT 09/0000Z 22.0N 59.5W 70 KT
72HR VT 10/0000Z 24.0N 62.0W 70 KT
96HR VT 11/0000Z 27.0N 64.5W 70 KT
120HR VT 12/0000Z 30.0N 65.5W 70 KT

$$
FORECASTER AVILA

[JonathanBelles]

000
WTNT22 KNHC 070844
TCMAT2
HURRICANE BERTHA FORECAST/ADVISORY NUMBER 17
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
0900 UTC MON JUL 07 2008

HURRICANE CENTER LOCATED NEAR 19.3N 50.2W AT 07/0900Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 15 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 987 MB
MAX SUSTAINED WINDS 65 KT WITH GUSTS TO 80 KT.
64 KT....... 20NE 0SE 0SW 20NW.
50 KT....... 50NE 30SE 20SW 50NW.
34 KT.......100NE 60SE 40SW 100NW.
12 FT SEAS..250NE 150SE 75SW 250NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 19.3N 50.2W AT 07/0900Z
AT 07/0600Z CENTER WAS LOCATED NEAR 19.1N 49.4W

FORECAST VALID 07/1800Z 19.9N 52.5W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 20NE 0SE 0SW 20NW.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 40SW 100NW.

FORECAST VALID 08/0600Z 20.8N 55.0W
MAX WIND 75 KT...GUSTS 90 KT.
64 KT... 30NE 20SE 0SW 30NW.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

FORECAST VALID 08/1800Z 21.7N 57.1W
MAX WIND 80 KT...GUSTS 100 KT.
64 KT... 30NE 20SE 0SW 30NW.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

FORECAST VALID 09/0600Z 22.7N 59.0W
MAX WIND 80 KT...GUSTS 100 KT.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

FORECAST VALID 10/0600Z 25.0N 62.0W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 11/0600Z 28.0N 64.0W
MAX WIND 70 KT...GUSTS 85 KT.

OUTLOOK VALID 12/0600Z 30.5N 64.5W
MAX WIND 70 KT...GUSTS 85 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 19.3N 50.2W

NEXT ADVISORY AT 07/1500Z

$$
FORECASTER KNABB

[JonathanBelles]

000
WTNT32 KNHC 070845
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 17
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 AM AST MON JUL 07 2008

...BERTHA BECOMES THE FIRST HURRICANE OF THE 2008 ATLANTIC SEASON...

AT 500 AM AST...0900Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 19.3 NORTH...LONGITUDE 50.2 WEST OR ABOUT 845 MILES...
1365 KM...EAST OF THE NORTHERN LEEWARD ISLANDS.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 17 MPH...28 KM/HR.
A CONTINUED WEST-NORTHWESTWARD MOTION WITH A GRADUAL DECREASE IN
FORWARD SPEED IS EXPECTED DURING THE NEXT COUPLE OF DAYS...AS
BERTHA REMAINS OVER THE WATERS OF THE CENTRAL TROPICAL ATLANTIC.
IT IS STILL TOO EARLY TO DETERMINE IF BERTHA WILL EVENTUALLY AFFECT
ANY LAND AREAS.

MAXIMUM SUSTAINED WINDS HAVE INCREASED AND ARE NOW NEAR 75 MPH...120
KM/HR...WITH HIGHER GUSTS. SOME ADDITIONAL STRENGTHENING IS
FORECAST DURING THE NEXT COUPLE OF DAYS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 987 MB...29.15 INCHES.

REPEATING THE 500 AM AST POSITION...19.3 N...50.2 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 17 MPH. MAXIMUM SUSTAINED WINDS...75
MPH. MINIMUM CENTRAL PRESSURE...987 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 AM AST.

$$
FORECASTER KNABB

[Chacor]

[cycloneye]

340
WTNT32 KNHC 071433
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM AST MON JUL 07 2008

...BERTHA STRENGTHENS OVER THE CENTRAL ATLANTIC...COULD REACH
CATEGORY TWO INTENSITY LATER TODAY...

AT 1100 AM AST...1500Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 19.6 NORTH...LONGITUDE 51.3 WEST OR ABOUT 775 MILES...
1250 KM...EAST OF THE NORTHERN LEEWARD ISLANDS.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 15 MPH...24 KM/HR.
A GRADUAL TURN TOWARDS THE NORTHWEST WITH A REDUCTION IN FORWARD
SPEED IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 90 MPH...150 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24
HOURS...AND BERTHA COULD BECOME A CATEGORY TWO HURRICANE LATER
TODAY OR TONIGHT.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 994 MB...29.35 INCHES.

REPEATING THE 1100 AM AST POSITION...19.6 N...51.3 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 15 MPH. MAXIMUM SUSTAINED WINDS...90
MPH. MINIMUM CENTRAL PRESSURE...994 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM AST.

$$
FORECASTER RHOME

WTNT42 KNHC 071432
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM EDT MON JUL 07 2008

BERTHA'S SATELLITE PRESENTATION HAS BECOME MORE IMPRESSIVE DURING
THE LAST 6 HOURS WITH A DISTINCT EYE NOW APPARENT. THE INITIAL
INTENSITY IS INCREASED TO 80 KT IN LINE WITH THE CONSENSUS OF THE
VARIOUS SATELLITE ESTIMATES. IN THE SHORT-TERM...THERE ARE NO
APPARENT ENVIRONMENTAL FACTORS WHICH WOULD INHIBIT FURTHER
INTENSIFICATION TODAY AND THE OFFICIAL FORECAST NOW CALLS FOR
BERTHA TO BECOME A CATEGORY TWO HURRICANE. HOWEVER...THE INTENSITY
FORECAST BECOMES MORE UNCERTAIN BEYOND 36 HOURS AS THE GLOBAL
MODELS DISAGREE ON THE DETAILS OF THE DEVELOPMENT OF AN UPPER-LEVEL
TROUGH OVER THE WESTERN ATLANTIC. THE GFS FORECAST THE MOST
UNFAVORABLE ENVIRONMENT WITH BERTHA ESSENTIALLY RUNNING INTO THE
TROUGH. NOT SURPRISINGLY...THE SHIPS AND LGEM STATISTICAL
MODELS...WHICH INCLUDE ATMOSPHERIC INFORMATION FROM THE GFS...SHOW
CONSIDERABLE WEAKENING. MEANWHILE...THE UKMET...GFDL...AND HWRF
MODELS SHOWS A MUCH MORE FAVORABLE ENVIRONMENT AND DELAY WEAKENING
UNTIL THE VERY END OF THE FORECAST PERIOD. THE OFFICIAL INTENSITY
FORECAST LEANS MORE TOWARDS THE HIGHER SHEAR SCENARIO INDICATED BY
THE GFS BUT DOES NOT WEAKEN BERTHA AS FAST AS THE SHIPS AND LGEM
MODELS.

THERE HAS BEEN LITTLE CHANGE IN THE HURRICANE'S HEADING DURING THE
LAST 6 HOURS WITH THE INITIAL MOTION ESTIMATE ESSENTIALLY
UNCHANGED... 285/13. HOWEVER...BERTHA IS BEGINNING TO ENCOUNTER A
WEAKNESS IN THE SUBTROPICAL RIDGE WHICH SHOULD RESULT IN A GRADUAL
TURN TOWARDS THE NORTH AND A REDUCTION IN FORWARD SPEED. THE
MODELS GENERALLY AGREE ON THIS EVOLUTION...BUT THERE REMAINS SOME
SPREAD AMONGST THE MODELS ON WHAT LONGITUDE BERTHA WILL TURN NORTH.
WHILE THE DEGREE OF THE TURN HAS IMPORTANT IMPLICATIONS REGARDING
POTENTIAL IMPACTS TO BERMUDA...IT IS MUCH TO EARLY TO DETERMINE IF
BERTHA WILL ACTUALLY THREATEN THAT ISLAND. HOWEVER...INTERESTS IN
BERMUDA SHOULD MONITOR THE PROGRESS OF THIS SYSTEM. THE NEW
OFFICIAL FORECAST IS NUDGED SLIGHTLY EASTWARD TOWARD THE TRACK
MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 07/1500Z 19.6N 51.3W 80 KT
12HR VT 08/0000Z 20.3N 53.3W 90 KT
24HR VT 08/1200Z 21.2N 55.5W 90 KT
36HR VT 09/0000Z 22.1N 57.5W 85 KT
48HR VT 09/1200Z 23.2N 59.2W 80 KT
72HR VT 10/1200Z 25.5N 62.0W 75 KT
96HR VT 11/1200Z 28.5N 63.5W 70 KT
120HR VT 12/1200Z 31.0N 63.5W 70 KT

$$
FORECASTER RHOME

[Chacor]

Corrected advisory issued.

634
WTNT32 KNHC 071455
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 18...CORRECTED
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM AST MON JUL 07 2008

...CORRECTED PRESSURE...

...BERTHA STRENGTHENS OVER THE CENTRAL ATLANTIC...COULD REACH
CATEGORY TWO INTENSITY LATER TODAY...

AT 1100 AM AST...1500Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 19.6 NORTH...LONGITUDE 51.3 WEST OR ABOUT 775 MILES...
1250 KM...EAST OF THE NORTHERN LEEWARD ISLANDS.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 15 MPH...24 KM/HR.
A GRADUAL TURN TOWARDS THE NORTHWEST WITH A REDUCTION IN FORWARD
SPEED IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 90 MPH...150 KM/HR...WITH HIGHER
GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 24
HOURS...AND BERTHA COULD BECOME A CATEGORY TWO HURRICANE LATER
TODAY OR TONIGHT.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 975 MB...28.79 INCHES.

REPEATING THE 1100 AM AST POSITION...19.6 N...51.3 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 15 MPH. MAXIMUM SUSTAINED WINDS...90
MPH. MINIMUM CENTRAL PRESSURE...975 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM AST.

$$
FORECASTER RHOME

[cycloneye]

724
WTNT32 KNHC 072035
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 19
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM AST MON JUL 07 2008

...BERTHA STRENGTHEN TO A MAJOR HURRICANE WITH 115 MPH WINDS...

AT 500 PM AST...2100Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 20.1 NORTH...LONGITUDE 52.1 WEST OR ABOUT 730 MILES...
1175 KM...EAST-NORTHEAST OF THE NORTHERN LEEWARD ISLANDS AND ABOUT
1150 MILES...1855 KM...SOUTHEAST OF BERMUDA.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 12 MPH...19 KM/HR.
A GRADUAL TURN TOWARD THE NORTHWEST WITH A DECREASE IN FORWARD SPEED
IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS HAVE INCREASED TO NEAR 115 MPH...185
KM/HR...WITH HIGHER GUSTS. BERTHA IS NOW A CATEGORY THREE HURRICANE
ON THE SAFFIR-SIMPSON HURRICANE SCALE. FLUCTUATIONS IN INTENSITY
ARE LIKELY DURING THE NEXT DAY OR TWO.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 948 MB...27.99 INCHES.

REPEATING THE 500 PM AST POSITION...20.1 N...52.1 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...115
MPH. MINIMUM CENTRAL PRESSURE...948 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 PM AST.

$$
FORECASTER RHOME

[hurricanefloyd5]

...Bertha strengthen to a major hurricane with 115 mph winds...

at 500 PM AST...2100z...the center of Hurricane Bertha was located
near latitude 20.1 north...longitude 52.1 west or about 730 miles...
1175 km...east-northeast of the northern Leeward Islands and about
1150 miles...1855 km...southeast of Bermuda.

Bertha is moving toward the west-northwest near 12 mph...19 km/hr.
A gradual turn toward the northwest with a decrease in forward speed
is expected over the next couple of days.

Maximum sustained winds have increased to near 115 mph...185
km/hr...with higher gusts. Bertha is now a category three hurricane
on the Saffir-Simpson hurricane scale. Fluctuations in intensity
are likely during the next day or two.

Hurricane force winds extend outward up to 25 miles...35 km...from
the center...and tropical storm force winds extend outward up to 115
miles...185 km.

Estimated minimum central pressure is 948 mb...27.99 inches.

Repeating the 500 PM AST position...20.1 N...52.1 W. Movement
toward...west-northwest near 12 mph. Maximum sustained winds...115
mph. Minimum central pressure...948 mb.

The next advisory will be issued by the National Hurricane Center at
1100 PM AST.

$$
Forecaster Rhome

[cycloneye]

354
WTNT42 KNHC 072035
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 19
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM EDT MON JUL 07 2008

BERTHA'S SATELLITE PRESENTATION HAS CONTINUED TO IMPROVE THIS
AFTERNOON WITH A VERY DISTINCT EYE NOW SURROUNDED BY A RING OF COLD
CLOUD TOPS. SUBJECTIVE DVORAK T NUMBERS WERE UNANIMOUSLY 5.0 BUT
OBJECTIVE NUMBERS HAVE INCREASED TO 6.0 FOR THE PAST 3 HOURS. THIS
SUPPORTS AN INITIAL INTENSITY OF 100 KT MAKING BERTHA A MAJOR
CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON HURRICANE SCALE.
BERTHA'S INTENSIFICATION TO MAJOR HURRICANE TODAY HIGHLIGHTS THE
DIFFICULTIES OF FORECASTING RAPID INTENSITY CHANGES. IN THE
SHORT-TERM...SHEAR IS EXPECTED TO BE LOW AND THE INTENSITY WILL BE
PRIMARILY CONTROLLED BY EYEWALL CYCLES. AS A RESULT...SOME
FLUCTUATIONS IN INTENSITY ARE LIKELY. IN A DAY OR TWO...THE GFS
MODEL STILL INDICATES INCREASING SHEAR. THE SHIPS AND LGEM
STATISTICAL MODELS...WHICH BASE THEIR SHEAR ESTIMATES FROM THE
GFS...SHOW WEAKENING BEYOND 24 HOURS AND SO DOES THE OFFICIAL
FORECAST.

BERTHA HAS BEEN MOVING MORE TOWARDS THE NORTHWEST DURING THE LAST
COUPLE OF HOURS WITH A REDUCTION IN FORWARD SPEED...BOTH INDICATIONS
THAT THE HURRICANE HAS REACHED THE MUCH-ANTICIPATED WEAKNESS IN THE
RIDGE. SINCE BERTHA COULD BE WOBBLING...THE INITIAL MOTION
ESTIMATE BASED ON A 12 HOUR AVERAGE IS 300/10. TRACK GUIDANCE
REMAINS IN GOOD AGREEMENT ON A GRADUAL NORTHWARD TURN DURING THE
NEXT 2-3 DAYS. THEREAFTER...GLOBAL MODELS SUGGEST THAT THE
STEERING CURRENTS COULD BECOME WEAK LEADING TO INCREASED UNCERTAINTY
IN THE TRACK FORECAST. EVEN THOUGH THE OFFICIAL FORECAST IS
SHIFTED A LITTLE TO THE EAST...IT IS STILL WAY TOO SOON TO
DETERMINE WHETHER OR NOT BERTHA WILL AFFECT BERMUDA.


FORECAST POSITIONS AND MAX WINDS

INITIAL 07/2100Z 20.1N 52.1W 100 KT
12HR VT 08/0600Z 20.8N 53.5W 100 KT
24HR VT 08/1800Z 21.7N 55.4W 95 KT
36HR VT 09/0600Z 22.9N 57.3W 90 KT
48HR VT 09/1800Z 24.0N 59.0W 85 KT
72HR VT 10/1800Z 26.5N 61.5W 80 KT
96HR VT 11/1800Z 29.0N 62.5W 75 KT
120HR VT 12/1800Z 31.5N 62.5W 75 KT

$$
FORECASTER RHOME

[cycloneye]

WTNT22 KNHC 080235
TCMAT2
HURRICANE BERTHA FORECAST/ADVISORY NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
0300 UTC TUE JUL 08 2008

HURRICANE CENTER LOCATED NEAR 20.8N 52.8W AT 08/0300Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 10 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 952 MB
EYE DIAMETER 15 NM
MAX SUSTAINED WINDS 105 KT WITH GUSTS TO 130 KT.
64 KT....... 20NE 0SE 0SW 20NW.
50 KT....... 50NE 30SE 20SW 50NW.
34 KT.......100NE 60SE 40SW 100NW.
12 FT SEAS..270NE 180SE 150SW 270NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 20.8N 52.8W AT 08/0300Z
AT 08/0000Z CENTER WAS LOCATED NEAR 20.5N 52.3W

FORECAST VALID 08/1200Z 21.5N 54.2W
MAX WIND 100 KT...GUSTS 120 KT.
64 KT... 20NE 0SE 0SW 20NW.
50 KT... 50NE 30SE 20SW 50NW.
34 KT...100NE 60SE 40SW 100NW.

FORECAST VALID 09/0000Z 22.5N 56.0W
MAX WIND 100 KT...GUSTS 120 KT.
64 KT... 30NE 20SE 0SW 30NW.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 60SW 120NW.

FORECAST VALID 09/1200Z 23.5N 58.0W
MAX WIND 95 KT...GUSTS 115 KT.
64 KT... 30NE 20SE 0SW 30NW.
50 KT... 60NE 45SE 30SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

FORECAST VALID 10/0000Z 25.0N 59.5W
MAX WIND 85 KT...GUSTS 105 KT.
50 KT... 70NE 45SE 30SW 60NW.
34 KT...140NE 100SE 75SW 120NW.

FORECAST VALID 11/0000Z 27.5N 61.5W
MAX WIND 80 KT...GUSTS 100 KT.
50 KT... 70NE 45SE 30SW 60NW.
34 KT...140NE 100SE 75SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 12/0000Z 30.0N 62.0W
MAX WIND 75 KT...GUSTS 90 KT.

OUTLOOK VALID 13/0000Z 32.0N 62.0W
MAX WIND 75 KT...GUSTS 90 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 20.8N 52.8W

NEXT ADVISORY AT 08/0900Z

$$
FORECASTER AVILA

BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM AST MON JUL 07 2008

...POWERFUL HURRICANE BERTHA OVER OPEN WATERS...

AT 1100 PM AST...0300Z...THE EYE OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 20.8 NORTH...LONGITUDE 52.8 WEST OR ABOUT 695 MILES...
1115 KM...EAST-NORTHEAST OF THE NORTHERN LEEWARD ISLANDS AND ABOUT
1085 MILES...1745 KM...SOUTHEAST OF BERMUDA.

BERTHA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 12 MPH...19 KM/HR. A
GRADUAL TURN TO THE NORTHWEST WITH A DECREASE IN FORWARD SPEED IS
EXPECTED DURING THE NEXT 24 TO 48 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 120 MPH...195 KM/HR...WITH HIGHER
GUSTS. BERTHA IS A CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON
HURRICANE SCALE. FLUCTUATIONS IN INTENSITY ARE LIKELY DURING THE
12 TO 24 HOURS...FOLLOWED BY A GRADUAL WEAKENING.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 952 MB...28.11 INCHES.

REPEATING THE 1100 PM AST POSITION...20.8 N...52.8 W. MOVEMENT
TOWARD...WEST-NORTHWEST NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...120
MPH. MINIMUM CENTRAL PRESSURE...952 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 AM AST.

$$
FORECASTER AVILA
688
WTNT42 KNHC 080236
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 20
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM EDT MON JUL 07 2008

DURING THE AFTERNOON HOURS BETWEEN 1900 AND 2300 UTC...BOTH NHC AND
CIMSS OBJECTIVE T-NUMBERS WERE OSCILLATING AROUND 6.0 ON THE DVORAK
SCALE. NORMALLY THESE NUMBERS CORRESPOND TO AN INTENSITY OF 115
KNOTS. DURING THAT TIME THE EYE BECAME VERY DISTINCT AND WAS
SURROUNDED BY VERY COLD TOPS. BERTHA COULD HAVE REACHED A PEAK
INTENSITY A LITTLE BIT HIGHER THAN PREVIOUSLY ESTIMATED DURING THAT
PERIOD. SINCE THEN...OBJECTIVE T-NUMBERS HAVE COME DOWN A LITTLE
BIT AND NEW ESTIMATES SUPPORT AN INTENSITY OF 105 KNOTS. MINIMUM
CENTRAL PRESSURE HAS ALSO BEEN ADJUSTED. THE INTENSITY IS EXPECTED
TO BE CONTROLLED BY EYEWALL REPLACEMENT CYCLES DURING THE NEXT 12
TO 24 HOURS WHEN BERTHA COULD FLUCTUATE IN INTENSITY. THEREAFTER...
THE OFFICIAL FORECAST CALLS FOR SLIGHT WEAKENING DUE TO INCREASING
SHEAR BUT NOT AS MUCH WEAKENING AS PREDICTED BY THE SHIPS MODEL.
NEVERTHELESS...THE INTENSITY FORECAST CONTINUES TO BE HIGHLY
UNCERTAIN.

ON THE OTHER HAND...THE TRACK FORECAST HAS BECOME A LITTLE MORE
CERTAIN SINCE THE TRACK MODELS ARE IN BETTER AGREEMENT AND THE
GUIDANCE ENVELOPE IS SMALLER. BERTHA IS MOVING TOWARD THE
WEST-NORTHWEST OR 300 DEGREES AT 10 KNOTS WHILE APPROACHING A
WEAKNESS IN THE SUBTROPICAL RIDGE. THE RIDGE IS EXPECTED TO
REBUILD SOME AND THIS PATTERN WOULD FAVOR A CONTINUATION OF THE
WEST-NORTHWEST TRACK FOR A DAY OR TWO....FOLLOWED BY A GRADUAL TURN
TO THE NORTHWEST AND NORTH. BY DAYS 4 AND 5 THE STEERING CURRENTS
ARE FORECAST TO COLLAPSE AND BERTHA WILL PROBABLY MEANDER FOR A
LITTLE BIT.

BERTHA IS CERTAINLY NOT THE ONLY MAJOR HURRICANE THAT HAS FORMED IN
THE MONTH OF JULY. THE LAST OCCURRENCES WERE HURRICANES DENNIS AND
EMILY IN 2005.

FORECAST POSITIONS AND MAX WINDS

INITIAL 08/0300Z 20.8N 52.8W 105 KT
12HR VT 08/1200Z 21.5N 54.2W 100 KT
24HR VT 09/0000Z 22.5N 56.0W 100 KT
36HR VT 09/1200Z 23.5N 58.0W 95 KT
48HR VT 10/0000Z 25.0N 59.5W 85 KT
72HR VT 11/0000Z 27.5N 61.5W 80 KT
96HR VT 12/0000Z 30.0N 62.0W 75 KT
120HR VT 13/0000Z 32.0N 62.0W 75 KT

$$
FORECASTER AVILA

[x-y-no]

000
WTNT32 KNHC 081441
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM AST TUE JUL 08 2008

...BERTHA WEAKENS BUT STILL A CATEGORY TWO HURRICANE...

AT 1100 AM AST...1500Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 22.1 NORTH...LONGITUDE 53.8 WEST OR ABOUT 660 MILES...
1065 KM...EAST-NORTHEAST OF THE NORTHERN LEEWARD ISLANDS AND ABOUT
975 MILES...1570 KM...SOUTHEAST OF BERMUDA.

BERTHA IS MOVING TOWARD THE NORTHWEST NEAR 10 MPH...17 KM/HR...AND
THIS GENERAL MOTION IS EXPECTED TO CONTINUE WITH A REDUCTION IN
FORWARD SPEED DURING THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 105 MPH...165
KM/HR...WITH HIGHER GUSTS. ADDITIONAL WEAKENING IS FORECAST DURING
THE NEXT 24 HOURS.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES...45 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 115
MILES...185 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 970 MB...28.64 INCHES.

REPEATING THE 1100 AM AST POSITION...22.1 N...53.8 W. MOVEMENT
TOWARD...NORTHWEST NEAR 10 MPH. MAXIMUM SUSTAINED WINDS...105 MPH.
MINIMUM CENTRAL PRESSURE...970 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 PM AST.

$$
FORECASTER RHOME

[x-y-no]

000
WTNT22 KNHC 081440
TCMAT2
HURRICANE BERTHA FORECAST/ADVISORY NUMBER 22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1500 UTC TUE JUL 08 2008


HURRICANE CENTER LOCATED NEAR 22.1N 53.8W AT 08/1500Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT 9 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 970 MB
MAX SUSTAINED WINDS 90 KT WITH GUSTS TO 110 KT.
64 KT....... 25NE 20SE 15SW 25NW.
50 KT....... 50NE 40SE 30SW 50NW.
34 KT.......100NE 60SE 40SW 100NW.
12 FT SEAS..240NE 180SE 150SW 240NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 22.1N 53.8W AT 08/1500Z
AT 08/1200Z CENTER WAS LOCATED NEAR 21.8N 53.5W

FORECAST VALID 09/0000Z 23.1N 54.9W
MAX WIND 85 KT...GUSTS 105 KT.
64 KT... 25NE 20SE 15SW 25NW.
50 KT... 50NE 40SE 30SW 50NW.
34 KT...100NE 60SE 40SW 100NW.

FORECAST VALID 09/1200Z 24.3N 56.4W
MAX WIND 80 KT...GUSTS 100 KT.
64 KT... 30NE 25SE 20SW 30NW.
50 KT... 60NE 50SE 40SW 60NW.
34 KT...120NE 90SE 60SW 120NW.

FORECAST VALID 10/0000Z 25.5N 57.8W
MAX WIND 80 KT...GUSTS 100 KT.
64 KT... 30NE 25SE 20SW 30NW.
50 KT... 60NE 50SE 40SW 60NW.
34 KT...120NE 90SE 75SW 120NW.

FORECAST VALID 10/1200Z 26.6N 58.7W
MAX WIND 75 KT...GUSTS 90 KT.
50 KT... 70NE 60SE 40SW 60NW.
34 KT...140NE 120SE 75SW 120NW.

FORECAST VALID 11/1200Z 28.5N 59.5W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 70NE 60SE 40SW 60NW.
34 KT...140NE 120SE 75SW 120NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 12/1200Z 30.5N 59.5W
MAX WIND 65 KT...GUSTS 80 KT.

OUTLOOK VALID 13/1200Z 32.5N 58.5W
MAX WIND 65 KT...GUSTS 80 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 22.1N 53.8W

NEXT ADVISORY AT 08/2100Z

$$
FORECASTER RHOME

[x-y-no]

000
WTNT42 KNHC 081440
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 22
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 AM EDT TUE JUL 08 2008

CONVENTIONAL AND MICROWAVE IMAGERY SHOW A RAPID DEGRADATION OF
BERTHA'S STRUCTURE DURING THE LAST 6 HOURS. THE EYE HAS
DISAPPEARED AND CLOUD TOPS HAVE WARMED CONSIDERABLY. THERE IS ALSO
EVIDENCE IN MICROWAVE IMAGERY THAT THE WESTERN PORTION OF THE
EYEWALL HAS ERODED. A BLEND OF THE FINAL T AND CI NUMBERS FROM THE
DVORAK TECHNIQUE SUPPORTS AN INITIAL INTENSITY OF 90 KT AND LATEST
OBJECTIVE T NUMBERS SUGGEST AN EVEN LOWER INTENSITY. THE INITIAL
INTENSITY IS CONSERVATIVELY SET AT 90 KT. IT WOULD APPEAR THAT
BERTHA HAS FINALLY ENCOUNTERED THE HIGHER SHEAR ENVIRONMENT WE'VE
BEEN FORECASTING. ADDITIONALLY...THE CYCLONE IS MOVING OVER
SLIGHTLY COOLER WATERS AND THERE ARE SOME INDICATIONS IN SATELLITE
IMAGERY THAT IT COULD BE ENTRAINING DRY AIR. BOTTOM LINE...THE
ENVIRONMENT LOOKS RATHER HOSTILE AND BERTHA SHOULD CONTINUE TO
WEAKEN IN THE SHORT-TERM. TOWARDS THE END OF THE FORECAST
PERIOD...THE SHEAR COULD RELAX AND SSTS INCREASE SO THERE IS SOME
POTENTIAL FOR A LITTLE RE-INTENSIFICATION. HOWEVER...GIVEN THE
UNCERTAINTY IN INTENSITY FORECASTING...THE OFFICIAL FORECAST MERELY
SHOWS SLOW WEAKENING THROUGH THE FORECAST PERIOD AND IS IN GOOD
AGREEMENT WITH A CONSENSUS OF THE VARIOUS INTENSITY MODELS.

BERTHA HAS BEEN MOVING A LITTLE TO THE RIGHT OF THE PREVIOUS
ESTIMATE OR 315/9. BERTHA SHOULD CONTINUE TO GRADUALLY TURN
NORTHWARD OVER THE NEXT COUPLE OF DAYS AS A MID-LEVEL RIDGE OVER
THE WESTERN ATLANTIC WEAKENS AND IS REPLACED BY A WEAK TROUGH.
SINCE THE STEERING CURRENTS COULD BECOME RATHER WEAK AS A RESULT OF
THIS EVOLUTION...BERTHA COULD MOVE SLOWLY AND ERRATICALLY
TOWARDS THE END OF THE FORECAST. IT IS FOR THIS REASON THAT
INTERESTS IN BERMUDA SHOULD CONTINUE TO MONITOR THE PROGRESS OF
THIS SYSTEM. TRACK MODELS HAVE NOT CHANGED SIGNIFICANTLY SINCE THE
LAST FORECAST SO ONLY COSMETIC CHANGES TO THE OFFICIAL TRACK
FORECAST ARE NEEDED AT THIS TIME.

FORECAST POSITIONS AND MAX WINDS

INITIAL 08/1500Z 22.1N 53.8W 90 KT
12HR VT 09/0000Z 23.1N 54.9W 85 KT
24HR VT 09/1200Z 24.3N 56.4W 80 KT
36HR VT 10/0000Z 25.5N 57.8W 80 KT
48HR VT 10/1200Z 26.6N 58.7W 75 KT
72HR VT 11/1200Z 28.5N 59.5W 70 KT
96HR VT 12/1200Z 30.5N 59.5W 65 KT
120HR VT 13/1200Z 32.5N 58.5W 65 KT

$$
FORECASTER RHOME

[cycloneye]

370
WTNT42 KNHC 082031
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 23
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM EDT TUE JUL 08 2008

BERTHA'S SATELLITE PRESENTATION CONTINUES TO DEGRADE THIS AFTERNOON
AND DVORAK DATA T-NUMBERS HAVE FALLEN DURING THE LAST 6 HOURS. THE
INITIAL INTENSITY IS LOWERED TO 75 KT BASED ON AN AVERAGE OF THE
VARIOUS INTENSITY ESTIMATES. INDEED...BERTHA'S RAPID
INTENSIFICATION YESTERDAY HAS BEEN EQUALED BY ITS RAPID WEAKENING
TODAY. SUCH INTENSITY FLUCTUATIONS REMAIN A FORECASTING CHALLENGE
AND SERVE AS AN IMPORTANT REMINDER FOR THE UNCERTAINTIES ASSOCIATED
WITH INTENSITY FORECASTS. GIVEN THE CURRENT TREND IN SATELLITE
IMAGERY...CONTINUED WEAKENING IS POSSIBLE IN THE SHORT-TERM. MOST
OF THE INTENSITY MODELS SUGGEST THAT BERTHA MIGHT EVEN REGAIN SOME
STRENGTH LATER IN THE FORECAST AS THE SHEAR RELAXES AND THE SSTS
INCREASE. DUE TO THE UNCERTAINTY...THE OFFICIAL FORECAST SHOWS
SLIGHT WEAKENING IN THE SHORT-TERM WITH LITTLE CHANGE THEREAFTER.

BERTHA CONTINUES MOVING NORTHWESTWARD WITH AN INITIAL MOTION
ESTIMATE OF 310/10. BERTHA SHOULD CONTINUE TO GRADUALLY TURN
NORTHWARD OVER THE NEXT COUPLE OF DAYS AS A MID-LEVEL RIDGE OVER
THE WESTERN ATLANTIC WEAKENS AND IS REPLACED BY A WEAK TROUGH. THIS
EVOLUTION OF THE LARGE-SCALE PATTERN COULD RESULT IN THE STEERING
CURRENTS BECOMING RATHER WEAK BEYOND 72 HOURS...AND BERTHA COULD
MOVE SLOWLY AND ERRATICALLY TOWARDS THE END OF THE FORECAST. IT IS
FOR THIS REASON THAT INTERESTS IN BERMUDA SHOULD CONTINUE TO
MONITOR THE PROGRESS OF THIS SYSTEM. TRACK MODELS HAVE NOT CHANGED
SIGNIFICANTLY SINCE THE LAST ADVISORY AND NEITHER HAS THE OFFICIAL
FORECAST.

FORECAST POSITIONS AND MAX WINDS

INITIAL 08/2100Z 22.7N 54.8W 75 KT
12HR VT 09/0600Z 23.6N 56.0W 70 KT
24HR VT 09/1800Z 24.8N 57.4W 65 KT
36HR VT 10/0600Z 26.0N 58.5W 65 KT
48HR VT 10/1800Z 27.0N 59.2W 65 KT
72HR VT 11/1800Z 29.0N 60.0W 60 KT
96HR VT 12/1800Z 31.0N 59.5W 60 KT
120HR VT 13/1800Z 33.0N 58.5W 60 KT

$$
FORECASTER RHOME

[JonathanBelles]

000
WTNT32 KNHC 090231
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM AST TUE JUL 08 2008

...BERTHA CONTINUES TOWARD THE NORTHWEST OVER THE ATLANTIC...

AT 1100 PM AST...0300Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 23.1 NORTH...LONGITUDE 55.8 WEST OR ABOUT 580 MILES...
935 KM...NORTHEAST OF THE NORTHERN LEEWARD ISLANDS AND ABOUT 840
MILES...1350 KM...SOUTHEAST OF BERMUDA.

BERTHA IS MOVING TOWARD THE NORTHWEST NEAR 12 MPH...19 KM/HR.
THIS MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 TO 36 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 80 MPH...130 KM/HR...WITH HIGHER
GUSTS. NO SIGNIFICANT CHANGE IN STRENGTH IS FORECAST DURING THE
NEXT DAY OR TWO.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES...45 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140
MILES...220 KM.

LARGE SWELLS AND HIGH SURF COULD BEGIN TO AFFECT PORTIONS OF BERMUDA
LATE TOMORROW.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 985 MB...29.09 INCHES.

REPEATING THE 1100 PM AST POSITION...23.1 N...55.8 W. MOVEMENT
TOWARD...NORTHWEST NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...80 MPH.
MINIMUM CENTRAL PRESSURE...985 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
500 AM AST.

$$
FORECASTER AVILA

[JonathanBelles]

000
WTNT22 KNHC 090230
TCMAT2
HURRICANE BERTHA FORECAST/ADVISORY NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
0300 UTC WED JUL 09 2008

HURRICANE CENTER LOCATED NEAR 23.1N 55.8W AT 09/0300Z
POSITION ACCURATE WITHIN 25 NM

PRESENT MOVEMENT TOWARD THE NORTHWEST OR 310 DEGREES AT 10 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 985 MB
MAX SUSTAINED WINDS 70 KT WITH GUSTS TO 85 KT.
64 KT....... 25NE 15SE 15SW 15NW.
50 KT....... 50NE 30SE 30SW 30NW.
34 KT.......120NE 60SE 45SW 75NW.
12 FT SEAS..240NE 180SE 200SW 240NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 23.1N 55.8W AT 09/0300Z
AT 09/0000Z CENTER WAS LOCATED NEAR 22.8N 55.4W

FORECAST VALID 09/1200Z 24.0N 57.0W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 25NE 15SE 15SW 15NW.
50 KT... 50NE 30SE 30SW 30NW.
34 KT...120NE 60SE 45SW 75NW.

FORECAST VALID 10/0000Z 25.5N 58.5W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 30NE 15SE 15SW 15NW.
50 KT... 60NE 45SE 30SW 30NW.
34 KT...120NE 90SE 45SW 60NW.

FORECAST VALID 10/1200Z 27.0N 60.0W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 30NE 15SE 15SW 15NW.
50 KT... 60NE 45SE 30SW 30NW.
34 KT...120NE 90SE 45SW 60NW.

FORECAST VALID 11/0000Z 28.0N 60.5W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 70NE 45SE 30SW 45NW.
34 KT...140NE 90SE 45SW 90NW.

FORECAST VALID 12/0000Z 30.0N 61.0W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 70NE 45SE 30SW 45NW.
34 KT...140NE 90SE 45SW 90NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 225 NM
ON DAY 4 AND 300 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 13/0000Z 31.5N 61.0W
MAX WIND 65 KT...GUSTS 80 KT.

OUTLOOK VALID 14/0000Z 33.5N 60.0W
MAX WIND 60 KT...GUSTS 75 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 23.1N 55.8W

NEXT ADVISORY AT 09/0900Z

$$
FORECASTER AVILA



000
WTNT42 KNHC 090231
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 24
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
1100 PM EDT TUE JUL 08 2008

THERE HAS BEEN NO SIGNIFICANT CHANGE IN THE CLOUD PATTERN ASSOCIATED
WITH BERTHA. THERE IS A LITTLE BIT OF SOUTHEASTERLY SHEAR AND MOST
OF THE DEEP CONVECTION IS IN A WELL-DEFINED CYCLONICALLY CURVED
CONVECTIVE BAND TO THE WEST OF THE CENTER. BASED ON DVORAK
T-NUMBERS...THE BEST ESTIMATE OF THE INTENSITY IS 70 KNOTS. I AM
NOT QUITE SURE IF BERTHA HAS GIVEN UP AND WILL CONTINUE TO WEAKEN.
THE HURRICANE IS HEADING FOR WARMER WATERS AND LOWER SHEAR SO
REINTENSIFICATION IS NOT OUT OF THE QUESTION. BECAUSE OF THE MIXED
SIGNALS AMONG GUIDANCE...WITH THE SHIPS MODEL WEAKENING THE
HURRICANE AND BOTH GFDL AND HWRF SUGGESTING SLIGHT
STRENGTHENING...THE OFFICIAL FORECAST HAS OPTED TO KEEP BERTHA AS A
70 KT HURRICANE FOR THE NEXT 3 DAYS. THEREAFTER...THE SHEAR IS
FORECAST TO INCREASE AND GRADUAL WEAKENING IS INDICATED.

BERTHA HAS CONTINUED TO MOVE TOWARD THE NORTHWEST OR 310 DEGREES AT
10 KNOTS. A GRADUAL TURN TO THE NORTH IS EXPECTED BEYOND 48 HOURS
AS THE MID-LEVEL RIDGE CURRENTLY NORTH OF THE CYCLONE WEAKENS AND A
SHORT WAVE APPROACHES THE U.S. EAST COAST FROM THE WEST.
HOWEVER...THIS GENERAL NORTHWARD MOTION BETWEEN 48 AND 120 HOURS IS
EXPECTED TO BE PAINFULLY SLOW SINCE STEERING CURRENTS ARE FORECAST
TO BE VERY WEAK. THERE WAS A SLIGHT CHANGE IN THE 00Z GUIDANCE.
UNANIMOUSLY...THEY ALL SHIFTED A DEGREE OR TWO WESTWARD...INCLUDING
THE HWRF WHICH WAS FARTHER EAST AND HAS NOW JOINED THE REST OF THE
MODEL SUITE. THE OFFICIAL TRACK FORECAST WAS SHIFTED A LITTLE BIT
TO THE WEST AND IS NOW ON THE RIGHT SIDE OF THE GUIDANCE
ENVELOPE...IN FACT...JUST EAST OF THE GFDL AND THE HWRF. I DO NOT
WANT TO CHANGE THE TRACK TOO MUCH SINCE I WOULD NOT BE SURPRISED IF
THE GUIDANCE SHIFTS BACK TO THE EAST IN THE NEXT RUN.


FORECAST POSITIONS AND MAX WINDS

INITIAL 09/0300Z 23.1N 55.8W 70 KT
12HR VT 09/1200Z 24.0N 57.0W 70 KT
24HR VT 10/0000Z 25.5N 58.5W 70 KT
36HR VT 10/1200Z 27.0N 60.0W 70 KT
48HR VT 11/0000Z 28.0N 60.5W 70 KT
72HR VT 12/0000Z 30.0N 61.0W 70 KT
96HR VT 13/0000Z 31.5N 61.0W 65 KT
120HR VT 14/0000Z 33.5N 60.0W 60 KT

$$
FORECASTER AVILA

[Kerry04]

HURRICANE BERTHA DISCUSSION NUMBER 25
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 AM EDT WED JUL 09 2008

THE CLOUD PATTERN ASSOCIATED WITH BERTHA APPEARS TO HAVE BECOME
SLIGHTLY MORE CIRCULAR AND ORGANIZED OVER THE PAST FEW HOURS. A
SLIGHT EXPANSION OF THE CIRRUS CANOPY OVER THE SOUTHERN AND WESTERN
PORTIONS OF THE CIRCULATION SUGGESTS THAT VERTICAL SHEAR MAY BE
DECREASING. THIS IS CONSISTENT WITH WATER VAPOR ANIMATIONS WHICH
SHOW AN UPPER-LEVEL CYCLONE NEAR 27N 68W MOVING WESTWARD AND
FARTHER AWAY FROM THE TROPICAL CYCLONE. DVORAK SATELLITE CURRENT
INTENSITY ESTIMATES ARE ONLY 55 TO 65 KT AND THEREFORE THE CURRENT
WIND SPEED IS ADJUSTED TO 65 KT FOR THIS ADVISORY. THE SHIPS MODEL
WHICH USES THE GFS UPPER-LEVEL WIND FORECAST DOES NOT SHOW A
DECREASE IN SHEAR OR ANY STRENGTHENING. HOWEVER THE GFDL AND HWRF
MODELS...BOTH OF WHICH HAVE SOME LIMITED SKILL IN INTENSITY
PREDICTION...FORECAST A MODEST INCREASE IN STRENGTH OVER THE NEXT
48 HOURS OR SO. MY WIND SPEED FORECAST ONLY HINTS AT THE
POSSIBILITY OF RE-INTENSIFICATION. HOWEVER BERTHA WILL CONTINUE TO
TRAVERSE WARM WATERS FOR A COUPLE OF DAYS AND SINCE OTHER
ENVIRONMENTAL FACTORS DO NOT APPEAR INHIBITING...IT WOULD NOT BE
SURPRISING TO SEE IT BECOME STRONGER AGAIN.

ALTHOUGH THERE HAS BEEN A FAIR AMOUNT OF SCATTER IN THE CENTER FIXES
OVERNIGHT...MY ESTIMATE OF INITIAL MOTION IS STILL NORTHWESTWARD OR
305/9. THERE HAS BEEN NO SIGNIFICANT CHANGE IN THE TRACK FORECAST
REASONING FROM THE PREVIOUS ADVISORY PACKAGE. A MID-TROPOSPHERIC
ANTICYCLONE TO THE NORTH OF BERTHA IS LIKELY TO WEAKEN AS A 500 MB
SHORTWAVE TROUGH MOVES OFF OF THE U.S. EAST COAST IN 2-3 DAYS.
THIS EVOLUTION SHOULD CAUSE THE MOTION OF THE HURRICANE TO SLOW
FURTHER AND TO TURN MORE NORTHWARD AROUND THAT TIME. GLOBAL MODELS
INDICATE THAT THE TROUGH WILL MISS BERTHA AND LEAVE IT IN WEAK
STEERING CURRENTS UNTIL NEAR THE END OF THE FORECAST PERIOD WHEN A
NEW AND STRONGER TROUGH APPROACHES THE EAST COAST. A VERY SLOW
MOTION IS INDICATED AROUND DAYS 3-4 DUE TO THE WEAK STEERING AND
BERTHA COULD ALSO MOVE ERRATICALLY AROUND THAT TIME. BY DAY 5 THE
OFFICIAL FORECAST SHOWS A SLIGHT INCREASE IN NORTH-NORTHEASTWARD
MOTION IN RESPONSE TO THE SECOND TROUGH. THE OFFICIAL TRACK
FORECAST IS QUITE CLOSE TO THE VARIABLE DYNAMICAL MODEL
CONSENSUS...TVCN.

IT IS STILL TOO EARLY TO KNOW WHETHER BERTHA WILL HAVE AN IMPACT ON
BERMUDA. INTERESTS ON THAT ISLAND SHOULD CONTINUE TO MONITOR THE
PROGRESS OF THIS HURRICANE OVER THE NEXT COUPLE OF DAYS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 09/0900Z 23.5N 56.5W 65 KT
12HR VT 09/1800Z 24.2N 57.8W 65 KT
24HR VT 10/0600Z 25.4N 59.2W 70 KT
36HR VT 10/1800Z 26.8N 60.2W 70 KT
48HR VT 11/0600Z 28.0N 61.0W 70 KT
72HR VT 12/0600Z 30.0N 61.5W 70 KT
96HR VT 13/0600Z 31.0N 61.5W 65 KT
120HR VT 14/0600Z 33.0N 61.0W 60 KT

$$
FORECASTER PASCH

[cycloneye]

WTNT32 KNHC 092032
TCPAT2
BULLETIN
HURRICANE BERTHA ADVISORY NUMBER 27
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM AST WED JUL 09 2008

...BERTHA STRENGTHENS BACK TO A CATEGORY TWO HURRICANE...

AT 500 PM AST...2100Z...THE CENTER OF HURRICANE BERTHA WAS LOCATED
NEAR LATITUDE 24.8 NORTH...LONGITUDE 58.1 WEST OR ABOUT 560 MILES...
900 KM...NORTHEAST OF THE NORTHERN LEEWARD ISLANDS AND ABOUT 660
MILES...1060 KM...SOUTHEAST OF BERMUDA.

BERTHA IS MOVING TOWARD THE NORTHWEST NEAR 12 MPH...19 KM/HR. A
GRADUAL TURN TOWARD THE NORTH-NORTHWEST WITH A DECREASE IN FORWARD
SPEED IS EXPECTED DURING THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 105 MPH...165 KM/HR...WITH HIGHER
GUSTS. ADDITIONAL STRENGTHENING IS FORECAST DURING THE NEXT 24
HOURS AND BERTHA COULD AGAIN BECOME A MAJOR HURRICANE.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 30 MILES...45 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 140
MILES...220 KM.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 970 MB...28.64 INCHES.

LARGE SWELLS AND HIGH SURF COULD BEGIN AFFECTING PORTIONS OF BERMUDA
TONIGHT OR TOMORROW.

REPEATING THE 500 PM AST POSITION...24.8 N...58.1 W. MOVEMENT
TOWARD...NORTHWEST NEAR 12 MPH. MAXIMUM SUSTAINED WINDS...105 MPH.
MINIMUM CENTRAL PRESSURE...970 MB.

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
1100 PM AST.

$$
FORECASTER RHOME

WTNT42 KNHC 092032
TCDAT2
HURRICANE BERTHA DISCUSSION NUMBER 27
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL022008
500 PM EDT WED JUL 09 2008

BERTHA'S SATELLITE PRESENTATION HAS DRAMATICALLY IMPROVED DURING THE
LAST 6 HOURS. THE CYCLONE NOW HAS A DISTINCTIVE EYE AND IS
SURROUNDED BY A SYMMETRIC RING OF COLD CLOUD TOPS. THE INITIAL
INTENSITY IS RAISED TO 90 KT BASED ON A BLEND OF THE SATELLITE
CLASSIFICATIONS FROM SAB AND TAFB. BERTHA IS FORECAST TO BE IN A
SEEMINGLY FAVORABLE ENVIRONMENT FOR THE NEXT DAY OR SO AND
CONTINUED STRENGTHENING IS EXPECTED IN THE SHORT-TERM. BEYOND 36
HOURS...VERTICAL SHEAR IS STILL EXPECTED TO GRADUALLY INCREASE AND
SSTS SLOWLY FALL. THIS ENVIRONMENT IS EXPECTED TO RESULT IN A SLOW
WEAKENING TREND THROUGH THE END OF THE FORECAST PERIOD. IT SHOULD
BE NOTED THAT BERTHA COULD BECOME A LITTLE STRONGER THAN CURRENTLY
FORECAST IN THE FIRST 24 HOURS.

BERTHA HAS RECENTLY WOBBLED A LITTLE RIGHT OF THE PREVIOUS MOTION
ESTIMATE BUT THE 12 HOUR AVERAGE MOTION IS ESSENTIALLY
UNCHANGED...305/10. THE TRACK FORECAST PHILOSOPHY IS THE SAME AS
IN THE PREVIOUS ADVISORY. A MID-TROPOSPHERIC ANTICYCLONE
CURRENTLY OVER THE WESTERN ATLANTIC IS FORECAST TO MOVE
NORTHEASTWARD WHILE A SHORTWAVE TROUGH MOVES OFF OF THE U.S. EAST
COAST. THIS SHOULD RESULT IN BERTHA MAKING A GRADUAL TURN TOWARD
THE NORTH DURING THE NEXT 2-3 DAYS. HOWEVER...THIS TROUGH IS
FORECAST TO BYPASS BERTHA TO THE NORTH AND LEAVE IT BEHIND IN
RELATIVELY WEAK STEERING CURRENTS. ACCORDINGLY...THE OFFICIAL
FORECAST SHOWS A SLOW NORTHWARD MOTION AT DAYS 3 AND 4. A SECOND
TROUGH MOVING OFF THE UNITED STATES EAST COAST ON DAY 5 COULD
RESULT IN SOME NORTHWARD ACCELERATION LATE IN THE FORECAST PERIOD.
IN GENERAL...TRACK MODELS HAVE CHANGED LITTLE SINCE THE LAST
ADVISORY...AND THE NEW OFFICIAL TRACK FORECAST IS ESSENTIALLY AN
UPDATE OF THE PREVIOUS ONE.

IT IS STILL TOO EARLY TO KNOW WHETHER BERTHA WILL HAVE AN IMPACT ON
BERMUDA. INTERESTS ON THAT ISLAND SHOULD CONTINUE TO MONITOR THE
PROGRESS OF THIS HURRICANE OVER THE NEXT COUPLE OF DAYS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 09/2100Z 24.8N 58.1W 90 KT
12HR VT 10/0600Z 25.6N 59.2W 100 KT
24HR VT 10/1800Z 26.8N 60.2W 100 KT
36HR VT 11/0600Z 28.0N 61.0W 100 KT
48HR VT 11/1800Z 29.1N 61.3W 95 KT
72HR VT 12/1800Z 31.0N 61.5W 85 KT
96HR VT 13/1800Z 32.5N 61.0W 80 KT
120HR VT 14/1800Z 35.5N 60.0W 75 KT

$$
FORECASTER RHOME