EPAC: TROPICAL DEPRESSION MARTY (16E)

[I-wall]

Looking impressive tonight. Only six hours ago it looked terrible, but it looks much better now. I wouldnt be surprised to if this is named a TD tomorrow am.

[I-wall]

I just saw the latest qscat and saw some 40-50 kt winds, and the circulation is much better defined. I think this will upgraded to a tropical storm in the next 6-12 hours.

[clfenwi]

ABPZ20 KNHC 160536
TWOEP
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1100 PM PDT TUE SEP 15 2009

FOR THE EASTERN NORTH PACIFIC...EAST OF 140 DEGREES WEST LONGITUDE..

THE BROAD AREA OF LOW PRESSURE LOCATED ABOUT 350 MILES SOUTH-
SOUTHWEST OF THE SOUTHERN TIP OF BAJA CALIFORNIA CONTINUES TO SHOW
SOME SIGNS OF ORGANIZATION. THIS SYSTEM IS EXPECTED TO MOVE SLOWLY
WEST-NORTHWESTWARD OR NORTHWESTWARD...AND IT COULD DEVELOP INTO A
TROPICAL CYCLONE BEFORE REACHING COOLER WATERS IN A COUPLE OF DAYS.
THERE IS A HIGH CHANCE...GREATER THAN 50 PERCENT...OF THIS SYSTEM
BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.

$$
FORECASTER PASCH

[Kingarabian]

Dvorak estimates are at 2.0-2.5. I think it should be a TD or a tropical storm in the upcoming advisory...

[HURAKAN]

Looking better

[HURAKAN]

16/0600 UTC 18.0N 112.4W T2.0/2.0 97E -- East Pacific

[HURAKAN]

TROPICAL DEPRESSION SIXTEEN-E SPECIAL ADVISORY NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
430 AM PDT WED SEP 16 2009

...AND YET ANOTHER TROPICAL DEPRESSION FORMS IN THE NORTHEASTERN
PACIFIC...

AT 430 AM PDT...1130 UTC... THE CENTER OF THE NEWLY-FORMED TROPICAL
DEPRESSION SIXTEEN-E WAS LOCATED NEAR LATITUDE 18.7 NORTH...
LONGITUDE 112.6 WEST OR ABOUT 340 MILES...545 KM...SOUTH-SOUTHWEST
OF CABO SAN LUCAS MEXICO.

THE DEPRESSION IS MOVING TOWARD THE NORTH-NORTHWEST NEAR 2 MPH...3
KM/HR. THIS SLOW MOTION SHOULD CONTINUE DURING THE NEXT 24 HOURS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER
GUSTS. THE DEPRESSION COULD BECOME A TROPICAL STORM LATER TODAY.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1005 MB...29.68 INCHES.

...SUMMARY OF 430 AM PDT INFORMATION...
LOCATION...18.7N 112.6W
MAXIMUM SUSTAINED WINDS...35 MPH
PRESENT MOVEMENT...NORTH-NORTHWEST OR 335 DEGREES AT 2 MPH
MINIMUM CENTRAL PRESSURE...1005 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
730 AM PDT.

$$
FORECASTER AVILA


TROPICAL DEPRESSION SIXTEEN-E SPECIAL DISCUSSION NUMBER 1
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
430 AM PDT WED SEP 16 2009

SATELLITE IMAGES INDICATE THAT DEEP CONVECTION HAS INCREASED NEAR
THE CENTER OF THE LOW PRESSURE AREA AND THE CIRCULATION HAS BECOME
BETTER DEFINED. DVORAK T-NUMBER HAVE ALSO INCREASED INDICATING THAT
THE SYSTEM IS NOW A TROPICAL DEPRESSION. VISIBLE IMAGES LATER THIS
MORNING WILL LIKELY PROVIDE A BETTER ESTIMATE OF THE LOCATION OF
THE CENTER OF THE DEPRESSION. INITIAL INTENSITY IS 30 KNOTS AND
THERE IS A POTENTIAL FOR SOME STRENGTHENING AND THE DEPRESSION
COULD BECOME A TROPICAL STORM WITHIN THE NEXT 24 HOURS.
THEREAFTER...STRONG SHEAR AND COOL WATERS ARE EXPECTED TO BE
AFFECTING THE SYSTEM...AND WEAKENING SHOULD BEGIN. IN FACT...THE
SYSTEM COULD BE A REMNANT LOW IN ABOUT 3 DAYS OR EARLIER.

THE DEPRESSION IS DRIFTING TOWARD THE NORTHWEST...EMBEDDED WITHIN
LIGHT STEERING CURRENTS. A WEAK RIDGE IS FORECAST TO DEVELOP OVER
MEXICO AND WILL PROVIDE SOME NORTH-NORTHWEST STEERING TO THE
CYCLONE. THIS IS CONSISTENT WITH MOST OF TRACK GUIDANCE AND THE
OFFICIAL FORECAST IS VERY CLOSE TO THE CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 16/1130Z 18.7N 112.6W 30 KT
12HR VT 16/1800Z 18.9N 112.8W 35 KT
24HR VT 17/0600Z 19.5N 113.0W 40 KT
36HR VT 17/1800Z 20.0N 113.2W 30 KT
48HR VT 18/0600Z 21.0N 113.5W 25 KT
72HR VT 19/0600Z 22.5N 114.0W 20 KT...REMNANT LOW
96HR VT 20/0600Z 24.0N 114.5W 20 KT...REMNANT LOW
120HR VT 21/0600Z...DISSIPATED

$$
FORECASTER AVILA

[HURAKAN]

TROPICAL STORM MARTY DISCUSSION NUMBER 2
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
800 AM PDT WED SEP 16 2009

EARLY MORNING VISIBLE SATELLITE IMAGERY SHOW THAT THE CENTER OF THE
CYCLONE IS LOCATED NEAR THE EASTERN EDGE OF THE DEEP CONVECTION. A
1305 UTC QUIKSCAT PASS REVEALED SOME BELIEVABLE 35 KT WIND
VECTORS...AND THIS IS THE BASIS FOR UPGRADING THE DEPRESSION TO A
TROPICAL STORM...THE THIRTEENTH OF THE 2009 EASTERN NORTH PACIFIC
HURRICANE SEASON.

MARTY HAS ABOUT A 24-HOUR WINDOW OF OPPORTUNITY TO STRENGTHEN BEFORE
IT ENCOUNTERS INCREASING UPPER-LEVEL SOUTHWESTERLY WINDS.
THEREAFTER...THE CYCLONE WILL BE MOVING OVER SLOWLY DECREASING SSTS
WHICH SHOULD INDUCE A FASTER RATE OF DEMISE. THE UPDATED INTENSITY
FORECAST IS SLIGHTLY HIGHER THAN THE PREVIOUS ADVISORY THROUGH 48
HOURS DUE TO THE INCREASE IN THE INITIAL INTENSITY. HOWEVER...
MARTY IS STILL EXPECTED TO BECOME A REMNANT LOW IN AROUND 72 HOURS.

THE INITIAL MOTION ESTIMATE IS A HIGHLY UNCERTAIN 325/3. THE TRACK
FORECAST SCENARIO REMAINS THE SAME AS THE PREVIOUS ADVISORY. MARTY
IS CURRENTLY WITHIN AN AREA OF LIGHT STEERING FLOW....BUT A WEAK
RIDGE IS FORECAST TO BUILD OVER MEXICO DURING THE NEXT COUPLE OF
DAYS WHICH SHOULD CAUSE THE CYCLONE TO MOVE SLOWLY NORTH-
NORTHWESTWARD. THE OFFICIAL FORECAST IS CLOSE TO THE PREVIOUS NHC
TRACK AND THE MULTI-MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 16/1500Z 18.9N 112.4W 35 KT
12HR VT 17/0000Z 19.3N 112.6W 40 KT
24HR VT 17/1200Z 19.8N 112.8W 45 KT
36HR VT 18/0000Z 20.6N 113.1W 40 KT
48HR VT 18/1200Z 21.4N 113.3W 30 KT
72HR VT 19/1200Z 23.0N 114.0W 25 KT...REMNANT LOW
96HR VT 20/1200Z 24.0N 114.5W 20 KT...REMNANT LOW
120HR VT 21/1200Z...DISSIPATED

$$
FORECASTER BROWN

[HURAKAN]

A look at Marty

[somethingfunny]

Does not appear to be a major player in SW US weather anymore. Looks like it'll parallel the coast and then spin down like they usually do....

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[Macrocane]

Marty has just spat out a few outflow boundaries, he's having a hard time.

[HURAKAN]

EP, 16, 2009091618, , BEST, 0, 187N, 1125W, 40, 1003, TS

Up to 40 knots

[HurricaneRobert]

It looks like a jellybean.

[cycloneye]

000
WTPZ31 KNHC 162037
TCPEP1
BULLETIN
TROPICAL STORM MARTY ADVISORY NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
200 PM PDT WED SEP 16 2009

...MARTY A LITTLE STRONGER...

AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL STORM MARTY WAS
LOCATED NEAR LATITUDE 18.9 NORTH...LONGITUDE 112.6 WEST OR ABOUT 325
MILES...525 KM...SOUTH-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

MARTY IS NEARLY STATIONARY. A SLOW NORTH-NORTHWESTWARD MOTION IS
EXPECTED TO BEGIN LATER TODAY....AND MARTY IS FORECAST TO MOVE
NORTH-NORTHWESTWARD THURSDAY AND THURSDAY NIGHT.

MAXIMUM SUSTAINED WINDS ARE NEAR 45 MPH...75 KM/HR...WITH HIGHER
GUSTS. SOME SLIGHT STRENGTHENING IS FORECAST DURING THE NEXT 24
HOURS.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 1001 MB...29.56 INCHES.

...SUMMARY OF 200 PM PDT INFORMATION...
LOCATION...18.9N 112.6W
MAXIMUM SUSTAINED WINDS...45 MPH
PRESENT MOVEMENT...STATIONARY
MINIMUM CENTRAL PRESSURE...1001 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
800 PM PDT.

$$
FORECASTER BROWN

000
WTPZ41 KNHC 162040
TCDEP1
TROPICAL STORM MARTY DISCUSSION NUMBER 3
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
200 PM PDT WED SEP 16 2009

VISIBLE SATELLITE IMAGERY INDICATES THAT MARTY HAS MOVED VERY LITTLE
SINCE THIS MORNING. THE CLOUD PATTERN IS THAT OF A VERY ASYMMETRIC
TROPICAL CYCLONE...WITH ALL OF THE DEEP CONVECTION OVER THE WESTERN
SEMICIRCLE OF THE STORM. DVORAK T-NUMBERS OF 2.5 AND 3.0 SUPPORT
INCREASING THE INITIAL INTENSITY TO 40 KT. A SHEAR ANALYSIS FROM
UW-CIMSS SHOWS ABOUT 15 KT OF SOUTHEASTERLY SHEAR OVER THE CYCLONE.
THE SHEAR IS FORECAST TO BECOME SOUTHERLY...THEN TURN SOUTHWESTERLY
IN ABOUT 24 HOURS. IT APPEARS THAT THERE IS SMALL WINDOW OF
OPPORTUNITY FOR MARTY TO STRENGTHEN DURING THE NEXT DAY...
THEREAFTER INCREASING SHEAR AND A LESS FAVORABLE THERMODYNAMIC
ENVIRONMENT SHOULD INDUCE A MORE RAPID RATE OF WEAKENING. THE
OFFICIAL INTENSITY FORECAST IS CLOSEST TO THE STATISTICAL GUIDANCE
FOR THE FIRST 24 HOURS...THEN IS IN GOOD AGREEMENT WITH THE
INTENSITY CONSENSUS THEREAFTER.

MARTY IS EXPECTED TO BEGIN MOVING SLOWLY NORTH-NORTHWESTWARD SOON
AS A WEAK RIDGE BUILDS TO THE EAST OF THE CYCLONE. THE NEW
FORECAST IS CLOSE TO THE PREVIOUS ADVISORY AND NEAR THE MIDDLE OF
THE GUIDANCE ENVELOPE DURING THE FIRST 48 HOURS. THEREAFTER...A
SIGNIFICANT WESTWARD SHIFT HAS BEEN MADE TO THE NHC TRACK...AS
NEARLY ALL OF THE DYNAMICAL MODELS TURN MARTY WESTWARD IN THE
LOW-LEVEL FLOW AS IT WEAKENS AND BECOME A SHALLOW SYSTEM.

FORECAST POSITIONS AND MAX WINDS

INITIAL 16/2100Z 18.9N 112.6W 40 KT
12HR VT 17/0600Z 19.2N 112.7W 45 KT
24HR VT 17/1800Z 19.7N 113.0W 50 KT
36HR VT 18/0600Z 20.4N 113.4W 45 KT
48HR VT 18/1800Z 21.2N 113.9W 35 KT
72HR VT 19/1800Z 22.6N 115.3W 30 KT...REMNANT LOW
96HR VT 20/1800Z 23.5N 117.0W 25 KT...REMNANT LOW
120HR VT 21/1800Z 23.5N 120.0W 20 KT...REMNANT LOW

$$
FORECASTER BROWN

[cycloneye]

000
WTPZ41 KNHC 170232
TCDEP1
TROPICAL STORM MARTY DISCUSSION NUMBER 4
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
800 PM PDT WED SEP 16 2009

MARTY HAS NOT BECOME SIGNIFICANTLY BETTER ORGANIZED SINCE EARLIER
TODAY. VISIBLE AND MICROWAVE IMAGES INDICATE THAT THE LOW-LEVEL
CENTER OF THE STORM REMAINS NEAR THE EASTERN EDGE OF THE MAIN MASS
OF DEEP CONVECTION. DVORAK INTENSITY ESTIMATES REMAIN AT 35 KT AND
45 KT FROM SAB AND TAFB RESPECTIVELY AND THE ADVISORY WIND SPEED IS
HELD AT 40 KT. VERTICAL SHEAR OVER MARTY IS EXPECTED TO CHANGE
FROM EASTERLY TO SOUTHWESTERLY...BUT REMAIN FAIRLY WEAK...DURING
THE NEXT 24 HOURS. THUS THERE REMAINS A SMALL WINDOW OF
OPPORTUNITY FOR THE TROPICAL CYCLONE TO STRENGTHEN. OCEANOGRAPHIC
ANALYSES SHOW THAT THE WATERS ALONG THE PROJECTED PATH OF MARTY ARE
SOMEWHAT WARMER THAN CLIMATOLOGY AND THIS COULD HELP THE CYCLONE
MAINTAIN ITS INTENSITY FOR A FEW DAYS. BY AROUND 36 HOURS...
HOWEVER...GLOBAL MODELS INDICATE A SUBSTANTIAL INCREASE IN SHEAR
ASSOCIATED WITH STRONG UPPER-LEVEL WEST-SOUTHWESTERLIES TO THE
NORTH OF 20N LATITUDE. THEREFORE WE EXPECT A WEAKENING TREND
WITHIN 1-2 DAYS AND MARTY SHOULD BE REDUCED TO A REMNANT LOW BY DAY
4 IF NOT EARLIER. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO
THE PREVIOUS ONE AND NOT FAR FROM THE MODEL CONSENSUS.

LATEST CENTER FIXES YIELD A MOTION ESTIMATE OF 340/3. THERE IS A
WEAKNESS IN THE MID-LEVEL RIDGE THAT EXTENDS FROM JUST NORTH OF
THE CYCLONE TO THE BAJA CALIFORNIA PENINSULA. THE GFDL AND HWRF
MODELS...ESPECIALLY THE LATTER...MAINTAIN MARTY AS A FAIRLY STRONG
TROPICAL CYCLONE AND THE HWRF TAKES THE SYSTEM OVER BAJA FOLLOWING
THE MID- TO UPPER-LEVEL FLOW. HOWEVER SINCE THE STORM IS LIKELY TO
WEAKEN DUE TO STRONG SHEAR...ITS STEERING SHOULD BE DOMINATED BY
THE LOWER-LEVEL FLOW. THIS IS THE SOLUTION GIVEN BY NEARLY ALL OF
THE OTHER AVAILABLE TRACK GUIDANCE THAT TURN MARTY GRADUALLY TO THE
LEFT IN RESPONSE TO A LOW-LEVEL RIDGE TO THE NORTHEAST AND NORTH OF
THE CYCLONE. THE OFFICIAL FORECAST IS ADJUSTED JUST A TRIFLE TO
THE NORTH OF THAT FROM THE PREVIOUS ADVISORY AND IS CLOSE TO THE
DYNAMICAL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 17/0300Z 19.2N 112.7W 40 KT
12HR VT 17/1200Z 19.6N 112.9W 45 KT
24HR VT 18/0000Z 20.4N 113.2W 50 KT
36HR VT 18/1200Z 21.2N 113.7W 45 KT
48HR VT 19/0000Z 22.1N 114.4W 35 KT
72HR VT 20/0000Z 23.5N 116.0W 30 KT
96HR VT 21/0000Z 24.0N 117.5W 25 KT...REMNANT LOW
120HR VT 22/0000Z 24.0N 120.0W 20 KT...REMNANT LOW

$$
FORECASTER PASCH

[HURAKAN]

TROPICAL STORM MARTY DISCUSSION NUMBER 5
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
200 AM PDT THU SEP 17 2009

THE CLOUD PATTERN HAS NOT CHANGED VERY MUCH DURING THE PAST FEW
HOURS...PERHAPS IT IS A LITTLE BIT LESS ORGANIZED. MICROWAVE
IMAGERY SHOWS THAT THE CENTER IS STILL NEAR THE NORTHERN EDGE OF
THE CONVECTION. QUIKSCAT AND ASCAT DATA FROM A FEW HOURS AGO...WHEN
THE CLOUD PATTERN WAS A LITTLE BETTER DEFINED...SHOWED A FEW RAIN
CONTAMINATED VECTORS OF 35 TO 40 KNOTS AND 30 KNOTS...RESPECTIVELY.
THE INITIAL INTENSITY IS KEPT AT 40 KNOTS. MARTY COULD STRENGTHEN A
LITTLE TODAY WHILE THE SHEAR IS LIGHT...BUT UNANIMOUSLY...ALL
GLOBAL MODELS SHOW A BAND OF UNFAVORABLE STRONG UPPER-LEVEL
WESTERLY WINDS OVER MARTY AS SOON AS 24 HOURS. THE FORECAST CALLS
FOR A GRADUAL WEAKENING AND MARTY SHOULD BECOME A REMNANT LOW BY 72
HOURS OR EARLIER.

MARTY APPEARS TO BE MOVING TOWARD THE NORTH-NORTHWEST AT 4 KNOTS
ALONG A WEAKNESS IN THE SUBTROPICAL RIDGE. THIS GENERAL MOTION
SHOULD CONTINUE DURING THE NEXT 24 HOUR OR SO. A GRADUAL TURN TO
THE WEST-NORTHWEST AND WEST SHOULD BEGIN AS MARTY WEAKENS AND
BECOME A SHALLOW SYSTEM STEERED BY THE LOW LEVEL FLOW. WITH THE
EXCEPTION OF THE HWRF WHICH BRINGS MARTY NORTHWARD OVER BAJA
CALIFORNIA...THE REMAINDER OF THE GUIDANCE TURNS MARTY TOWARD THE
WEST AND SO DOES THE OFFICIAL FORECAST. THE HWRF SOLUTION IS NOT
CONSISTENT WITH THE TRACK OF A WEAKENING CYCLONE STEERED BY THE
LOW-LEVEL FLOW.


FORECAST POSITIONS AND MAX WINDS

INITIAL 17/0900Z 19.7N 112.9W 40 KT
12HR VT 17/1800Z 20.2N 113.1W 45 KT
24HR VT 18/0600Z 21.0N 113.5W 45 KT
36HR VT 18/1800Z 22.0N 114.5W 40 KT
48HR VT 19/0600Z 23.0N 115.5W 30 KT
72HR VT 20/0600Z 24.0N 117.0W 25 KT...REMNANT LOW
96HR VT 21/0600Z 24.5N 118.5W 20 KT...REMNANT LOW
120HR VT 22/0600Z 24.5N 120.5W 20 KT...REMNANT LOW

$$
FORECASTER AVILA

[HURAKAN]

564
WTPZ41 KNHC 171438
TCDEP1
TROPICAL STORM MARTY DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
800 AM PDT THU SEP 17 2009

THE CLOUD PATTERN HAS BECOME A LITTLE LESS ORGANIZED DURING THE PAST
FEW HOURS AS THE CLOUD TOPS HAVE WARMED SLIGHTLY AND THE OVERALL
SHAPE HAS BECOME ELONGATED. AN AMSR-E MICROWAVE IMAGE FROM 0913
UTC SUGGESTS THAT THE CENTER WAS LOCATED SLIGHTLY SOUTHWEST OF THE
PREVIOUS ESTIMATES. THE INITIAL INTENSITY REMAINS 40 KT...WHICH
COULD BE A LITTLE GENEROUS. MARTY HAS LIKELY REACHED ITS PEAK
INTENSITY. SOUTHWESTERLY SHEAR IS EXPECTED TO INCREASE DURING THE
NEXT DAY OR TWO AND THE CYCLONE WILL BE MOVING INTO A DRIER AND
MORE STABLE AIRMASS. THESE NEGATIVE ENVIRONMENTAL FACTORS SHOULD
TRANSLATE INTO A WEAKENING TROPICAL CYCLONE. THE OFFICIAL FORECAST
IS AT THE LOW END OF THE GUIDANCE AND SHOWS MARTY BECOMING A
REMNANT LOW WITHIN 48 HOURS.

MARTY APPEARS TO BE MOVING SLOWLY NORTH-NORTHWESTWARD. THIS
GENERAL MOTION SHOULD CONTINUE DURING THE NEXT DAY OR TWO. AS
MARTY WEAKENS AND BECOMES A SHALLOW SYSTEM IT IS EXPECTED TO
TURN WESTWARD IN THE LOW-LEVEL FLOW. ALL OF THE TRACK
GUIDANCE...EXCEPT THE HWRF...AGREE WITH THIS SOLUTION. THE HWRF
KEEPS MARTY A DEEP SYSTEM AND MOVES IT INTO THE BAJA PENINSULA.
THIS MODEL IS CONSIDERED AN OUTLIER AT THIS TIME.

FORECAST POSITIONS AND MAX WINDS

INITIAL 17/1500Z 19.7N 113.1W 40 KT
12HR VT 18/0000Z 20.3N 113.4W 35 KT
24HR VT 18/1200Z 21.1N 113.9W 35 KT
36HR VT 19/0000Z 22.0N 114.8W 30 KT
48HR VT 19/1200Z 22.8N 115.8W 25 KT...REMNANT LOW
72HR VT 20/1200Z 23.8N 117.6W 25 KT...REMNANT LOW
96HR VT 21/1200Z 24.0N 119.0W 20 KT...REMNANT LOW
120HR VT 22/1200Z...DISSIPATED

$$
FORECASTER BROWN

[HURAKAN]

Still fighting

[HURAKAN]

TROPICAL STORM MARTY DISCUSSION NUMBER 10
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
800 AM PDT FRI SEP 18 2009

A BURST OF DEEP CONVECTION DEVELOPED NEAR THE CENTER OF MARTY OVER
THE PAST FEW HOURS...ALTHOUGH RECENTLY CLOUD TOP TEMPERATURES IN
THIS AREA HAVE BEGUN TO WARM. DVORAK CI-NUMBERS WERE 2.5 FROM TAFB
AND SAB AT 1200 UTC...AND THE INITIAL INTENSITY IS HELD AT 35 KT
FOR THIS ADVISORY. A QUIKSCAT PASS SHOULD PROVIDE SOME INFORMATION
ON THE INTENSITY AND STRUCTURE OF MARTY SHORTLY. VERTICAL WIND
SHEAR IS FORECAST BY THE SHIPS MODEL TO INCREASE TO OVER 20 KT
WITHIN 24 HOURS...AND MARTY WILL BE MOVING INTO A DRIER ATMOSPHERIC
ENVIRONMENT AND OVER COOLER SSTS. ALL OF THIS SHOULD RESULT IN A
GRADUAL WEAKENING... WITH MARTY EXPECTED TO BECOME A REMNANT LOW IN
A DAY OR TWO...AND DISSIPATE ALTOGETHER IN 3 OR 4 DAYS. THE
OFFICIAL INTENSITY FORECAST IS CLOSEST TO THE SHIPS AND LGEM.

AN AMSU PASS AT 0906 UTC SUGGESTED THAT MARTY WAS LOCATED A LITTLE
FARTHER SOUTHEAST THAN PREVIOUSLY ESTIMATED...AND THE INITIAL MOTION
ESTIMATE IS AN UNCERTAIN 305/06. AS MARTY BECOMES A SHALLOW SYSTEM
...IT WILL TURN TOWARD THE WEST-NORTHWEST AND EVENTUALLY TOWARD THE
WEST SOUTH OF THE LOW-LEVEL RIDGE. THE OFFICIAL FORECAST IS ADJUSTED
TO THE LEFT OF THE PREVIOUS PACKAGE BASED ON THE INITIAL POSITION
AND MOTION. THE NEW FORECAST IS ALSO FASTER...TRENDING TOWARD THE
TVCN MULTI-MODEL CONSENSUS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 18/1500Z 20.4N 114.8W 35 KT
12HR VT 19/0000Z 21.0N 115.6W 30 KT
24HR VT 19/1200Z 21.8N 116.8W 30 KT
36HR VT 20/0000Z 22.4N 118.2W 25 KT...REMNANT LOW
48HR VT 20/1200Z 22.5N 119.8W 20 KT...REMNANT LOW
72HR VT 21/1200Z 22.5N 122.5W 20 KT...REMNANT LOW
96HR VT 22/1200Z...DISSIPATED

$$
FORECASTER BRENNAN

[HURAKAN]

TROPICAL STORM MARTY ADVISORY NUMBER 11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
200 PM PDT FRI SEP 18 2009

...MARTY EXPECTED TO WEAKEN...

AT 200 PM PDT...2100 UTC...THE CENTER OF TROPICAL STORM MARTY WAS
LOCATED NEAR LATITUDE 21.1 NORTH...LONGITUDE 115.2 WEST OR ABOUT 360
MILES...580 KM...WEST-SOUTHWEST OF THE SOUTHERN TIP OF BAJA
CALIFORNIA.

MARTY IS MOVING TOWARD THE NORTHWEST NEAR 7 MPH...11 KM/HR. A TURN
TOWARD THE WEST-NORTHWEST AND THEN TOWARD THE WEST WITH A GRADUAL
INCREASE IN FORWARD SPEED IS EXPECTED IN THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH...65 KM/HR...WITH HIGHER
GUSTS. GRADUAL WEAKENING IS FORECAST...AND MARTY IS EXPECTED TO
BECOME A REMNANT LOW IN THE NEXT DAY OR TWO.

TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 70 MILES...110 KM
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1004 MB...29.65 INCHES.

...SUMMARY OF 200 PM PDT INFORMATION...
LOCATION...21.1N 115.2W
MAXIMUM SUSTAINED WINDS...40 MPH
PRESENT MOVEMENT...NORTHWEST OR 310 DEGREES AT 7 MPH
MINIMUM CENTRAL PRESSURE...1004 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
800 PM PDT.

$$
FORECASTER BRENNAN


TROPICAL STORM MARTY DISCUSSION NUMBER 11
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP162009
200 PM PDT FRI SEP 18 2009

DEEP CONVECTION IS NOW CONFINED TO A SMALL AREA WEST OF THE CENTER
OF MARTY...AS INCREASING VERTICAL SHEAR APPEARS TO BE TAKING A TOLL
ON THE SYSTEM. A QUIKSCAT PASS FROM 1355 UTC SHOWED A FEW
BELIEVABLE 35-KT AMBIGUITIES...AND THIS IS THE BASIS FOR THE
INITIAL INTENSITY FOR THIS ADVISORY. IF THE CONVECTION CONTINUES TO
DECREASE...MARTY SHOULD BEGIN TO WEAKEN TONIGHT. THE SHIPS MODEL
CONTINUES TO SHOW THE CYCLONE MOVING INTO A MORE HOSTILE
ENVIRONMENT WITHIN THE NEXT 24 HOURS...WITH VERTICAL SHEAR
INCREASING TO OVER 30 KT BY THAT TIME. THE SHEAR...ALONG WITH A
LESS FAVORABLE THERMODYNAMIC ATMOSPHERIC AND OCEANIC ENVIRONMENT
SHOULD RESULT IN MARTY BECOMING A REMNANT LOW IN 24 TO 36 HOURS.
MOST OF THE GLOBAL MODELS SHOW THE REMNANT LOW DISSIPATING BY 3
DAYS.

SEVERAL MICROWAVE PASSES BETWEEN 1300 AND 1400 UTC...INCLUDING
SSMI...SSMIS...QUIKSCAT...AND WINDSAT ALL SHOWED THAT THE LOW-LEVEL
CENTER WAS A LITTLE FARTHER NORTH THAN ANALYZED IN THE PREVIOUS
ADVISORY. THE LOW-LEVEL CENTER IS NOW A LITTLE EASIER TO FIND
DUE TO THE THINNING CONVECTIVE OVERCAST...AND CONFIDENCE IN THE
INITIAL MOTION ESTIMATE OF 310/06 IS A LITTLE HIGHER. THE TRACK
FORECAST PHILOSOPHY REMAINS UNCHANGED. MARTY WILL TURN TOWARD THE
WEST-NORTHWEST AND EVENTUALLY TOWARD THE WEST PRIOR TO DISSIPATION
AS IT FEELS THE INFLUENCE OF THE LOW-LEVEL RIDGE TO ITS NORTH. THE
OFFICIAL FORECAST IS ADJUSTED NORTH OF THE PREVIOUS PACKAGE DUE TO
THE INITIAL POSITION...AND TRENDS TOWARD THE FASTER TVCN MODEL
CONSENSUS BY 48 HOURS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 18/2100Z 21.1N 115.2W 35 KT
12HR VT 19/0600Z 21.7N 116.2W 30 KT
24HR VT 19/1800Z 22.4N 117.7W 30 KT
36HR VT 20/0600Z 22.6N 119.5W 25 KT...REMNANT LOW
48HR VT 20/1800Z 22.6N 121.5W 20 KT...REMNANT LOW
72HR VT 21/1800Z...DISSIPATED

$$
FORECASTER BRENNAN