CPAC : TROPICAL DEPRESSION LANA (06E)

[cycloneye]

ZCZC HFOTCDCP1 ALL
TTAA00 PHFO DDHHMM
TROPICAL STORM LANA DISCUSSION NUMBER 4
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
ISSUED BY NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1100 PM HST THU JUL 30 2009

LANE HAS DEVELOPED A CENTRAL CONVECTIVE FEATURE THIS EVENING...WITH
03Z SSM/IS DATA SUGGESTING GOOD CONVECTIVE BANDING NEAR THE CENTER.
SINCE THEN...THE CONVECTIVE TOPS HAVE WARMED SOMEWHAT. AMSU
INTENSITY ESTIMATES NEAR 03Z WERE 50-60 KT...WHILE QUIKSCAT DATA
NEAR 04Z SHOWED 40-45 KT WINDS NORTHEAST OF THE CENTER. THE
SATELLITE INTENSITY ESTIMATES ARE 45 KT FROM TAFB AND 55 KT FROM
SAB. THE INITIAL INTENSITY IS THE ROUGH AVERAGE OF THESE
VALUES...50 KT.

THE INITIAL MOTION IS 285/17. A LOW/MID-LEVEL RIDGE LOCATED TO THE
NORTH OF LANA SHOULD PROVIDE THE STEERING DURING THE NEXT SEVERAL
DAYS AS A LARGE UPPER-LEVEL LOW SEEN IN WATER VAPOR IMAGERY MOVES
WESTWARD FROM THE HAWAIIAN ISLANDS. THE TRACK GUIDANCE SUGGESTS
THIS PATTERN SHOULD STEER LANA GENERALLY WESTWARD TO WEST-
NORTHWESTWARD SOUTH OF HAWAII THROUGH THE FORECAST PERIOD.
OVERALL...THE GUIDANCE IS TIGHTLY CLUSTERED EXCEPT FOR THE OUTLYING
BAMD AND BAMM...WHICH FORECAST LANA TO MOVE NORTHWESTWARD THROUGH
OR NEAR THE HAWAIIAN ISLANDS. THE GUIDANCE ENVELOPE HAS AGAIN
SHIFTED A LITTLE TO THE NORTH...SO THE NEW TRACK WILL BE NUDGED A
LITTLE NORTH OF THE PREVIOUS FORECAST. THE NEW TRACK IS ALONG THE
SOUTH SIDE OF THE GUIDANCE ENVELOPE IN BEST AGREEMENT WITH THE GFS
AND GFDL MODELS.

LANA IS CURRENTLY IN AN ENVIRONMENT OF LIGHT SOUTHERLY WIND SHEAR
WITH FAIR TO GOOD CIRRUS OUTFLOW. THE LARGE-SCALE MODELS FORECAST
THAT LANA WILL GRADUALLY MOVE CLOSER TO THE STRONG SOUTHERLY AND
SOUTHWESTERLY FLOW ASSOCIATED WITH THE UPPER-LEVEL LOW...WHICH
SHOULD CAUSE A SIGNIFICANT INCREASE IN VERTICAL WIND SHEAR AFTER
24-36 HR. THE INTENSITY GUIDANCE CALLS FOR THE STORM TO REACH A
PEAK INTENSITY OF 60-65 KT BEFORE THE SHEAR INCREASES...AND THE NEW
INTENSITY FORECAST CALLS FOR A 65 KT PEAK INTENSITY IN 24 HR IN
AGREEMENT WITH THE PREVIOUS FORECAST. AFTER THAT...LANA SHOULD
STEADILY WEAKEN DUE TO THE SHEAR. THE UKMET AND ECMWF MODELS SHOW
VERY STRONG SHEAR BY 72 HR...AND IF THEY ARE CORRECT LANA COULD
WEAKEN FASTER THEN CURRENTLY FORECAST.

FORECAST POSITIONS AND MAX WINDS

INITIAL 31/0900Z 13.3N 144.6W 50 KT
12HR VT 31/1800Z 13.6N 147.0W 60 KT
24HR VT 01/0600Z 14.1N 149.8W 65 KT
36HR VT 01/1800Z 14.6N 152.7W 65 KT
48HR VT 02/0600Z 15.1N 155.5W 60 KT
72HR VT 03/0600Z 16.0N 161.0W 45 KT
96HR VT 04/0600Z 17.0N 166.5W 30 KT
120HR VT 05/0600Z 17.5N 172.0W 25 KT...REMNANT LOW

$$
FORECASTER BEVEN

[HURAKAN]

31/0600 UTC 13.0N 143.4W T3.5/3.5 LANA -- Central Pacific

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 31 JUL 2009 Time : 103000 UTC
Lat : 13:24:45 N Lon : 144:58:07 W

CI# /Pressure/ Vmax
3.4 / 995.2mb/ 53.0kt

Final T# Adj T# Raw T#
(3hr avg)
2.8 2.7 2.7

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -14.0C Cloud Region Temp : -43.5C

Scene Type : CURVED BAND with 0.46 ARC in LT GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : EAST PACIFIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : ON
Rapid Dissipation Flag : FLAG

****************************************************

[tolakram]

I think Hawaii will be ok.

Shear Tendency


from: http://cimss.ssec.wisc.edu/tropic/real- ... g9sht.html

[HURAKAN]

More deep convection

[HURAKAN]

TROPICAL STORM LANA ADVISORY NUMBER 5
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
ISSUED BY NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
500 AM HST FRI JUL 31 2009

...LANA WEAKENS A LITTLE AS IT CONTINUES TOWARD THE
WEST-NORTHWEST...

AT 500 AM HST...1500 UTC...THE CENTER OF TROPICAL STORM LANA WAS
LOCATED NEAR LATITUDE 13.6 NORTH...LONGITUDE 146.3 WEST OR ABOUT 720
MILES...1155 KM...SOUTHEAST OF HILO HAWAII.

LANA IS MOVING TOWARD THE WEST-NORTHWEST NEAR 18 MPH...30 KM/HR. A
GENERALLY WESTWARD MOTION WITH A GRADUAL DECREASE IN FORWARD SPEED
IS EXPECTED DURING THE NEXT COUPLE OF DAYS. ON THIS TRACK...THE AREA
OF STRONGEST WINDS ASSOCIATED WITH LANA SHOULD BE PASSING WELL TO
THE SOUTH OF THE HAWAIIAN ISLANDS IN ABOUT 36 TO 48 HOURS.

MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 50 MPH...85
KM/HR...WITH HIGHER GUSTS. NO SIGNIFICANT CHANGE IN STRENGTH IS
FORECAST DURING THE NEXT DAY OR TWO.

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.

...SUMMARY OF 500 AM HST INFORMATION...
LOCATION...13.6N 146.3W
MAXIMUM SUSTAINED WINDS...50 MPH
PRESENT MOVEMENT...WEST-NORTHWEST OR 285 DEGREES AT 18 MPH
MINIMUM CENTRAL PRESSURE...1000 MB

THE NEXT ADVISORY WILL BE ISSUED BY THE CENTRAL PACIFIC HURRICANE
CENTER AT 1100 AM HST.

$$
FORECASTER AVILA

TROPICAL STORM LANA DISCUSSION NUMBER 5
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
ISSUED BY NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
500 AM HST FRI JUL 31 2009

THE INTENSIFICATION TREND OBSERVED YESTERDAY HAS REVERSED AND
THE CLOUD PATTERN HAS DETERIORATED INSTEAD. IT APPEARS THAT SOME
SOUTHERLY SHEAR INDUCED BY A LARGE UPPER-LEVEL TROUGH JUST WEST OF
THE HAWAIIAN ISLANDS HAS BEGUN TO AFFECT THE CYCLONE. LANA CONSISTS
OF TWO CONVECTIVE AREAS SURROUNDING THE CENTER AND NOW HAS LESS
DEFINED OUTFLOW. DVORAK T-NUMBERS HAVE DECREASED AND THE INITIAL
INTENSITY HAS BEEN LOWERED TO 45 KNOTS. LANA STILL HAS THE
OPPORTUNITY TO STRENGTHEN SOME BEFORE THE SHEAR INCREASES FURTHER
IN ABOUT 24 TO 36 HOURS. THEREAFTER...A GRADUAL WEAKENING IS
INDICATED. MOST OF CURRENT INTENSITY GUIDANCE DOES NOT SHOW ANY
SIGNIFICANT STRENGTHENING EITHER...AND WEAKENS THE CYCLONE LATER IN
THE FORECAST PERIOD.

LANA IS FULLY EMBEDDED WITHIN THE TROPICAL TRADE WINDS AND IS MOVING
TOWARD THE WEST-NORTHWEST OR 285 DEGREES AT 17 KNOTS. THE CURRENT
WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE HAWAIIAN ISLANDS IS
FORECAST TO BE REPLACED BY A STRONGER RIDGE. THIS PATTERN EVOLUTION
SHOULD KEEP LANA ON A WEST-NORTHWEST TRACK WITH A SMALL DECREASE IN
FORWARD SPEED THROUGH FIVE DAYS. THIS WILL KEEP THE CYCLONE
WELL SOUTH OF THE HAWAIIAN ISLANDS. THE OFFICIAL FORECAST IS IN THE
MIDDLE OF THE TIGHTLY CLUSTERED GUIDANCE ENVELOPE.


FORECAST POSITIONS AND MAX WINDS

INITIAL 31/1500Z 13.6N 146.3W 45 KT
12HR VT 01/0000Z 14.0N 148.7W 50 KT
24HR VT 01/1200Z 14.5N 151.5W 50 KT
36HR VT 02/0000Z 15.0N 154.5W 45 KT
48HR VT 02/1200Z 15.5N 157.0W 40 KT
72HR VT 03/1200Z 16.5N 162.5W 35 KT
96HR VT 04/1200Z 17.0N 168.0W 30 KT
120HR VT 05/1200Z 17.5N 174.0W 25 KT...REMNANT LOW

$$
FORECASTER AVILA

[Ed Mahmoud]

Are they on vacation in Honolulu?


Or is Avila bored by the 1-0 no-hitter being pitched by the tropics.

[CrazyC83]

Are they on vacation in Honolulu?


Or is Avila bored by the 1-0 no-hitter being pitched by the tropics.

The NHC is handling advisories as the CPHC systems are down (they have been for nearly 24 hours).

[Derek Ortt]

don't agree with lowering the intensity. This is finally forming an inner core it seems

[margiek]

Are they on vacation in Honolulu?

CPHC and HFO are having technical issues and all of their products, including the non-tropical ones, are being backed up by a number of organizations (including NHC, OPC, and WFO Monterey). The backup plan may be laid out in the NHOP and I've never looked at it in that detail, or it may not be available to the general public, but I know that NHC is backed up by HPC and they have real-time tests during the year to ensure that works properly.

It's been quiet in the EPAC and the ATL hasn't started yet, so I imagine that NHC is glad to have a TC to forecast.

[HURAKAN]

Looking much better now

[HURAKAN]

Looking good.

[cycloneye]

18:00 UTC Models=55kts

WHXX01 KMIA 311922
CHGE77
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI
1922 UTC FRI JUL 31 2009

DISCLAIMER...NUMERICAL MODELS ARE SUBJECT TO LARGE ERRORS.
PLEASE REFER TO CPHC OFFICIAL FORECASTS FOR TROPICAL CYCLONE
AND SUBTROPICAL CYCLONE INFORMATION.

CENTRAL PACIFIC OBJECTIVE AIDS FOR

TROPICAL CYCLONE LANA (EP062009) 20090731 1800 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
090731 1800 090801 0600 090801 1800 090802 0600

LAT LON LAT LON LAT LON LAT LON
BAMS 13.6N 147.0W 14.1N 150.1W 14.6N 153.3W 15.3N 156.5W
BAMD 13.6N 147.0W 14.6N 149.6W 15.8N 151.6W 17.4N 153.4W
BAMM 13.6N 147.0W 14.2N 150.0W 14.7N 152.7W 15.3N 155.2W
LBAR 13.6N 147.0W 14.6N 149.9W 15.3N 152.8W 16.2N 155.3W
SHIP 55KTS 57KTS 58KTS 55KTS
DSHP 55KTS 57KTS 58KTS 55KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
090802 1800 090803 1800 090804 1800 090805 1800

LAT LON LAT LON LAT LON LAT LON
BAMS 16.2N 159.7W 18.1N 165.7W 20.4N 171.6W 22.7N 176.7W
BAMD 19.2N 155.2W 22.5N 157.9W 23.9N 159.8W 23.8N 162.0W
BAMM 16.0N 157.7W 18.4N 162.4W 20.8N 166.9W 22.3N 170.6W
LBAR 18.0N 158.0W 22.6N 161.7W 26.2N 162.2W .0N .0W
SHIP 50KTS 35KTS 21KTS 0KTS
DSHP 50KTS 35KTS 21KTS 0KTS

...INITIAL CONDITIONS...
LATCUR = 13.6N LONCUR = 147.0W DIRCUR = 285DEG SPDCUR = 16KT
LATM12 = 13.0N LONM12 = 143.9W DIRM12 = 285DEG SPDM12 = 16KT
LATM24 = 12.1N LONM24 = 140.6W
WNDCUR = 55KT RMAXWD = 15NM WNDM12 = 50KT
CENPRS = 995MB OUTPRS = 1011MB OUTRAD = 150NM SDEPTH = D
RD34NE = 85NM RD34SE = 50NM RD34SW = 50NM RD34NW = 85NM

[wxmann_91]

Probably did weaken quite a lot yesterday night as Microwave around 03Z showed weak and somewhat disorganized convection. Not really due to the shear IMO as much as the ingestion of some stable air from the north. Guess the diurnal max helped it regroup a little, but the inner core is still quite loose as it was yesterday.

[HURAKAN]

EP, 06, 2009073118, , BEST, 0, 136N, 1470W, 55, 995, TS

[cycloneye]

ZCZC HFOTCMCP1 ALL
TTAA00 PHFO DDHHMM
TROPICAL STORM LANA FORECAST/ADVISORY NUMBER 6
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
2100 UTC FRI JUL 31 2009

TROPICAL STORM CENTER LOCATED NEAR 13.7N 147.7W AT 31/2100Z
POSITION ACCURATE WITHIN 20 NM

PRESENT MOVEMENT TOWARD THE WEST OR 280 DEGREES AT 14 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 995 MB
MAX SUSTAINED WINDS 55 KT WITH GUSTS TO 65 KT.
50 KT....... 15NE 5SE 5SW 15NW.
34 KT....... 85NE 50SE 50SW 85NW.
12 FT SEAS..100NE 80SE 50SW 100NW.
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 13.7N 147.7W AT 31/2100Z
AT 31/1800Z CENTER WAS LOCATED NEAR 13.6N 147.0W

FORECAST VALID 01/0600Z 14.1N 150.0W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 15NE 5SE 5SW 15NW.
34 KT... 85NE 50SE 50SW 85NW.

FORECAST VALID 01/1800Z 14.7N 152.9W
MAX WIND 50 KT...GUSTS 60 KT.
50 KT... 10NE 0SE 0SW 10NW.
34 KT... 75NE 40SE 40SW 75NW.

FORECAST VALID 02/0600Z 15.2N 155.7W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 55NE 35SE 35SW 55NW.

FORECAST VALID 02/1800Z 15.7N 158.3W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 55NE 35SE 35SW 55NW.

FORECAST VALID 03/1800Z 16.5N 163.8W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 0SE 0SW 30NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 200 NM
ON DAY 4 AND 225 NM ON DAY 5...AND FOR INTENSITY NEAR 20 KT EACH DAY

OUTLOOK VALID 04/1800Z 17.1N 169.5W...DISSIPATING
MAX WIND 25 KT...GUSTS 35 KT.

OUTLOOK VALID 05/1800Z 17.6N 175.6W...REMNANT LOW
MAX WIND 20 KT...GUSTS 25 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 13.7N 147.7W

NEXT ADVISORY AT 01/0300Z

$$
FORECASTER KODAMA

000
WTPA41 PHFO 312057
TCDCP1

TROPICAL STORM LANA DISCUSSION NUMBER 6
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
1100 AM HST FRI JUL 31 2009

AFTER ORGANIZATION DETERIORATED EARLY LAST NIGHT...A BURST OF
CENTRAL CONVECTION AFTER 1200 UTC HELPED REINVIGORATE LANA. DVORAK
ESTIMATES FROM CPHC AND SAB CAME IN AT T3.5...OR 55 KT AND AN AMSU
INTENSITY ESTIMATE AT 1437 UTC ALSO INDICATED 55 KT. BASED ON THIS
CONSENSUS...THE INITIAL INTENSITY WILL BE RAISED TO 55 KT. THE 37
GHZ SSMI PASS FROM 1610 UTC HELPED LOCATE THE SYSTEM CENTER JUST
EAST OF THE DEEP CONVECTION CENTROID. INFRARED AND VISIBLE
SATELLITE IMAGES SHOW LANA/S OUTFLOW IS BEING RESTRICTED TO THE
WEST AND SOUTHWEST. THIS INDICATES UPPER SOUTHWESTERLIES...AND
INCREASED VERTICAL SHEAR...ARE STARTING TO AFFECT THE CYCLONE.

LANA IS MOVING WESTWARD TO THE SOUTH OF A SUBTROPICAL RIDGE THAT
WILL BUILD WESTWARD OVER THE NEXT SEVERAL DAYS. THIS WILL KEEP THE
CYCLONE TRACK GENERALLY TOWARD THE WEST TO WEST-NORTHWEST THROUGH
THE FORECAST PERIOD AND WELL SOUTH OF THE HAWAIIAN ISLANDS. THE
DYNAMICAL OBJECTIVE AIDS ARE TIGHTLY PACKED AND CONSISTENT WITH THE
PREVIOUS PACKAGE. THUS...THE CURRENT FORECAST FOLLOWS THE PREVIOUS
FORECAST AND IS CLOSE TO THE DYNAMICAL MODEL CONSENSUS...ESPECIALLY
THROUGH 72 HOURS.

IN TERMS OF INTENSITY...LANA MAY HAVE REACHED ITS PEAK. WHILE SST
VALUES ARE MORE THAN ADEQUATE...UPPER LEVEL SOUTHWESTERLIES ARE
EXPECTED TO INCREASE ALONG THE CYCLONE/S PROJECTED TRACK SO
VERTICAL SHEAR WILL TAKE ITS TOLL...ESPECIALLY FROM 24 TO 36
HOURS ONWARD. THE FORECAST FOLLOWS THE TREND OF THE ICON AND IVCN
WITH SLOW WEAKENING FROM 24 THROUGH 48 HOURS FOLLOWED BY A MORE
RAPID WEAKENING TO A REMNANT LOW BY 120 HOURS. IF VERTICAL WIND
SHEAR TAKES HOLD EARLIER...THE WEAKENING TREND WILL ALSO OCCUR
EARLIER.


FORECAST POSITIONS AND MAX WINDS

INITIAL 31/2100Z 13.7N 147.7W 55 KT
12HR VT 01/0600Z 14.1N 150.0W 55 KT
24HR VT 01/1800Z 14.7N 152.9W 50 KT
36HR VT 02/0600Z 15.2N 155.7W 45 KT
48HR VT 02/1800Z 15.7N 158.3W 45 KT
72HR VT 03/1800Z 16.5N 163.8W 35 KT
96HR VT 04/1800Z 17.1N 169.5W 25 KT...DISSIPATING
120HR VT 05/1800Z 17.6N 175.6W 20 KT...REMNANT LOW

$$
FORECASTER KODAMA

[I-wall]

Looking good.

What exactly does this graphic show?

[senorpepr]

194
FXHW60 PHFO 312005
AFDHFO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE HONOLULU HI
1000 AM HST FRI JUL 31 2009

SYNOPSIS

A BROAD HIGH PRESSURE SYSTEM LOCATED NORTHEAST OF THE STATE WILL
CONTINUE TO BRING TRADE WINDS OVER THE ISLANDS THROUGH EARLY NEXT
WEEK. THE STRENGTH OF THE TRADES MAY INCREASE OVER THE WEEKEND AS
TROPICAL CYCLONE LANA IS EXPECTED TO PASS SOUTH OF THE ISLANDS.
PASSING CLOUDS AND SHOWERS WILL AFFECT MAINLY WINDWARD AND
MOUNTAIN SECTIONS.



DISCUSSION

AREA OF LOW CLOUDS CARRIED BY THE TRADE WINDS HAS REACHED THE
ISLANDS THIS MORNING...BRINGING SOME SHOWERS TO MAINLY WINDWARD AND
MOUNTAIN AREAS OF THE ISLANDS. LATEST RADAR DATA INDICATE THERE MAY
BE SOME HEAVIER SHOWERS EMBEDDED...THOUGH THESE SHOWERS ARE NOT
HITTING THE RAIN GAGES THROUGHOUT THE STATE. THIS FIELD OF LOW
CLOUDS IS QUITE EXTENSIVE...AND MAY KEEP THE SKIES OVER WINDWARD AND
MOUNTAIN SECTIONS MORE CLOUDY TODAY. AN UPPER LEVEL LOW REMAINS NEAR
THE ISLANDS THIS MORNING AND WILL CAUSE THE AIR MASS OVER THE
ISLANDS TO REMAIN SOMEWHAT UNSTABLE. THUS EXPECT PASSING WETTING
SHOWERS TO AFFECT THE ISLANDS THROUGH TODAY...SPECIALLY OVER
WINDWARD AND MOUNTAIN AREAS.

THE HIGH PRESSURE NORTHEAST OF THE ISLANDS WILL PREVAIL THROUGH THE
WEEKEND INTO EARLY NEXT WEEK. IT WILL MAINTAIN MODERATE TRADE WINDS
TO THE AREA. TROPICAL STORM LANA FAR SOUTHEAST OF THE ISLANDS IS
STILL EXPECTED TO PASS SOUTH OVER THE WEEKEND...AND MAY LEAD TO A
SLIGHT INCREASE IN THE TRADE WIND DURING ITS PASSAGE DUE TO
POSSIBLE TIGHTENING OF SURFACE PRESSURE GRADIENT OVER THE ISLANDS.
THE UPPER LEVEL LOW IS STILL EXPECTED TO LIFT NORTH OVER THE NEXT
COUPLE OF DAYS...WITH A SLIGHT RIDGING DEVELOPING OVER THE ISLANDS.
EXPECT THE AIR MASS IN THE VICINITY TO BECOME MORE STABLE...AND IN
TURN CONDITIONS WILL BE BECOME MORE UNFAVORABLE FOR HEAVIER SHOWERS
TO DEVELOP.

LOOK FOR TRADE WIND WEATHER TO PREVAIL OVER THE ISLANDS THROUGH THE
WEEKEND INTO EARLY NEXT WEEK...WITH PASSING CLOUDS AND SHOWERS
AFFECTING THE ISLANDS AT TIMES. TRADE WINDS MAY INCREASE SLIGHTLY AS
TROPICAL STORM LANA PASSES SOUTH OF THE ISLANDS IN THE NEXT COUPLE
OF DAYS. SEE THE LATEST BULLETINS FROM CPHC ON TROPICAL STORM LANA
FOR THE MORE INFORMATION.



MARINE

SMALL CRAFT ADVISORY CONTINUES FOR THE TYPICALLY WINDY AREAS OF THE
THE ISLANDS COASTAL WATERS SUCH AS THE PAILOLO AND ALENUIHAHA
CHANNELS...MAALAEA BAY AND WATERS SOUTH OF THE BIG ISLAND THIS
MORNING. THIS COVERAGE MAY NEED TO BE EXPANDED TO OTHER MARINE ZONES
AS LANA PASSES SOUTH OF THE MAIN HAWAIIAN ISLANDS OVER THE WEEKEND.

THE KILO NALU WAVE SENSOR LOCATED OFF KEWALO BASIN AS WELL AS LANAI
BUOY CONTINUE TO SHOW A DOMINANT SOUTH SWELL WITH A SIGNIFICANT WAVE
HEIGHT OF ABOUT 3 FEET AT 17 SECONDS THIS MORNING. STILL EXPECT THE
SWELL TO INCREASE SLIGHTLY THROUGH THIS AFTERNOON. THUS HIGH SURF
ADVISORY REMAINS IN EFFECT THROUGH SUNDAY FOR SOUTH FACING SHORES OF
ALL ISLANDS.



HFO WATCHES/WARNINGS/ADVISORIES

SMALL CRAFT ADVISORY FOR THE PAILOLO AND ALENUIHAHA CHANNELS...
MAALAEA BAY AND WATERS SOUTH OF THE BIG ISLAND UNTIL 6 AM HST MONDAY.

HIGH SURF ADVISORY FOR SOUTH FACING SHORES OF ALL HAWAIIAN
ISLANDS UNTIL 6 PM HST SUNDAY.

[senorpepr]

This was posted in Talkin' Tropics...

Anyone knows when was the last time the Central Pacific had ACE numbers first than the Atlantic?

2000.

Upana (01C) was upgraded to a tropical storm at July 20, 2000 at 1800 UTC.
Alberto (03L) was upgraded to a tropical storm at August 4, 2000 at 1500 UTC.

[brunota2003]

The following post is NOT an official forecast and should not be used as such. It is just the opinion of the poster and may or may not be backed by sound meteorological data. It is NOT endorsed by any professional institution including storm2k.org For Official Information please refer to the NHC and NWS products.

I saw this weakening coming since last night, and knew she'd fall apart this morning. Was watching the convection just off to her west and their tops were being ripped off and sheared to the NE, definitely not a good thing for a tropical cyclone. As the Upper Low, pushed of to the NW some more, the trough of screaming winds weakened and narrowed, giving Lana a chance to reorganize and develop more convection.

Since then, Lana has gotten closer to the core of winds and once again has had it's convection stripped, the tops being blown rapidly to the NE. More storms are trying to redevelop over her, and I do think we'll see another popping of convection tonight before her bell is tolled.

Looking at the wind directions, they calm a little just in front of her (probably will help the current convection trying to develop a little later tonight) before she will once again be picked apart. The ULL is helping her and killing her at the same time. Give it another 24 to 48 hours and all that will be left is a LLC producing intermittent convective puffs as it struggles to keep the definition of a tropical cyclone, along with convection.

[cycloneye]

WTPA41 PHFO 010256
TCDCP1

TROPICAL STORM LANA DISCUSSION NUMBER 7
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP062009
500 PM HST FRI JUL 31 2009

FOLLOWING AN EARLY MORNING BURST OF CONVECTION...VERTICAL WIND SHEAR
HAS BEEN AFFECTING LANA. VISIBLE IMAGES SINCE 1800 UTC HAVE REVEALED
THE LOW LEVEL CENTER THROUGH A VEIL OF THIN HIGH CLOUDS. DVORAK
INTENSITY ESTIMATES FOR 0000 UTC CAME IN AT 55 KT FROM CPHC...SAB
AND THE CIMSS ADT. THESE GENEROUS VALUES WERE THE RESULT OF DVORAK
CONSTRAINTS WITH RAW DT VALUES INDICATING LOWER WIND SPEEDS.
RECENT IMAGES SHOW A NEW BURST OF DEEP CONVECTION DEVELOPING AROUND
THE NORTHERN QUADRANT OF THE CIRCULATION SO LANA CANNOT BE WRITTEN
OFF YET. THE INITIAL INTENSITY IS LOWERED TO 45 KT AS A BLEND OF
THE DVORAK CI AND DT VALUES.

THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST REASONING FROM THE
PREVIOUS PACKAGE REGARDING TRACK. LANA CONTINUES TO MOVE WESTWARD TO
THE SOUTH OF A MID-LEVEL SUBTROPICAL RIDGE THAT IS FORECAST TO
BUILD WESTWARD OVER THE NEXT SEVERAL DAYS. THIS WILL KEEP THE
CYCLONE MOVING GENERALLY TOWARD THE WEST TO WEST-NORTHWEST THROUGH
THE FORECAST PERIOD. DYNAMICAL OBJECTIVE AIDS HAVE A BIT MORE
SPREAD FOR THIS FORECAST CYCLE BUT STILL REMAIN RELATIVELY TIGHTLY
CLUSTERED. THE FORECAST TRACK REMAINS CLOSE TO THE PREVIOUS
FORECAST AND CLOSE TO THE CONSENSUS THROUGH 36 HOURS. BEYOND THAT
TIME THE FORECAST IS SOUTH OF THE CONSENSUS SINCE LANA IS EXPECTED
TO MOVE WITH THE LOW LEVEL EASTERLY FLOW AS A WEAKENING SYSTEM.
MOST OF THE DYNAMICAL AIDS REFLECT A PATH A BIT FARTHER TO THE
NORTH...APPARENTLY HOLDING ON TO A STRONGER AND DEEPER CYCLONE.

ALTHOUGH SST VALUES ARE MORE THAN ADEQUATE AT AROUND 27C...VERTICAL
WIND SHEAR FROM UPPER LEVEL SOUTHWESTERLIES WILL BE THE LIMITING
FACTOR ON INTENSITY. THE INITIAL INTENSITY WILL BE HELD AT 45 KT
THROUGH TONIGHT IN DEFERENCE TO NORMAL DIURNAL TENDENCY. STEADY
WEAKENING IS FORECAST FROM 24 HOURS AND BEYOND DUE TO THE EFFECTS
OF INCREASING VERTICAL SHEAR ALONG LANA/S PROJECTED TRACK. THE
FORECAST IS FOR LANA TO BE A REMNANT LOW BY 96 HOURS AND POTENTIALLY
SOONER.

FORECAST POSITIONS AND MAX WINDS

INITIAL 01/0300Z 14.1N 149.2W 45 KT
12HR VT 01/1200Z 14.4N 151.4W 45 KT
24HR VT 02/0000Z 15.0N 154.3W 35 KT
36HR VT 02/1200Z 15.5N 157.1W 30 KT
48HR VT 03/0000Z 15.8N 159.9W 25 KT
72HR VT 04/0000Z 16.7N 165.3W 20 KT...DISSIPATING
96HR VT 05/0000Z 17.3N 170.9W 20 KT...REMNANT LOW
120HR VT 06/0000Z 17.8N 176.3W 20 KT...REMNANT LOW

$$
FORECASTER KODAMA