Tropical Storm FLOSSIE (CPAC): Discussions, Analysis and Ima

[HURAKAN]

516
WHXX01 KMIA 100032
CHGE77
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0032 UTC FRI AUG 10 2007

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

EAST PACIFIC OBJECTIVE AIDS FOR

TROPICAL CYCLONE FLOSSIE (EP092007) 20070810 0000 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
070810 0000 070810 1200 070811 0000 070811 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 12.6N 133.1W 12.7N 135.1W 12.9N 136.8W 13.0N 138.4W
BAMD 12.6N 133.1W 12.6N 136.0W 12.6N 138.8W 12.6N 141.5W
BAMM 12.6N 133.1W 12.6N 135.7W 12.6N 138.1W 12.4N 140.3W
LBAR 12.6N 133.1W 12.8N 135.7W 13.7N 138.6W 14.7N 141.4W
SHIP 55KTS 62KTS 67KTS 69KTS
DSHP 55KTS 62KTS 67KTS 69KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
070812 0000 070813 0000 070814 0000 070815 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 13.2N 139.8W 13.7N 143.2W 15.2N 147.7W 16.9N 152.2W
BAMD 12.6N 144.2W 12.6N 149.3W 14.0N 154.5W 17.0N 158.2W
BAMM 12.2N 142.4W 11.9N 146.5W 12.6N 150.8W 14.1N 155.2W
LBAR 15.6N 143.8W 17.0N 147.6W 18.2N 150.4W 18.3N 152.0W
SHIP 68KTS 62KTS 56KTS 52KTS
DSHP 68KTS 62KTS 56KTS 52KTS

...INITIAL CONDITIONS...
LATCUR = 12.6N LONCUR = 133.1W DIRCUR = 265DEG SPDCUR = 13KT
LATM12 = 12.9N LONM12 = 130.4W DIRM12 = 262DEG SPDM12 = 13KT
LATM24 = 13.2N LONM24 = 127.8W
WNDCUR = 55KT RMAXWD = 15NM WNDM12 = 45KT
CENPRS = 994MB OUTPRS = 1010MB OUTRAD = 180NM SDEPTH = D
RD34NE = 45NM RD34SE = 60NM RD34SW = 45NM RD34NW = 45NM

$$
NNNN

[HURAKAN]

[RL3AO]

Hurricane at this update? I say no.

[Chacor]

Not gonna happen. Hold at 55 kt most likely.

[Chacor]

WTPZ44 KNHC 100231
TCDEP4
TROPICAL STORM FLOSSIE DISCUSSION NUMBER 6
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP092007
800 PM PDT THU AUG 09 2007

SATELLITE IMAGERY INDICATES THAT FLOSSIE HAS CHANGED LITTLE IN
ORGANIZATION WITH OCCASIONAL GLIMPSES OF A FORMATIVE EYE AND AN
EYEWALL FEATURE IN MICROWAVE IMAGERY. DVORAK INTENSITY ESTIMATES
FROM TAFB AND SAB REMAIN AT 55 KT...AND SO DOES THE OFFICIAL
ADVISORY INTENSITY. IN THE SHORT-TERM...THE INTENSITY FORECAST HAS
BECOME COMPLICATED BY THE DEVELOPMENT OF STRONG UPPER-LEVEL
EASTERLY FLOW NOW APPROACHING FLOSSIE FROM THE EAST. THE GLOBAL
MODELS ARE UNDERESTIMATING THIS FLOW POSSIBLY LEADING TO AN
OPTIMISTIC SHEAR FORECAST. ARRESTED DEVELOPMENT COULD RESULT IF
THIS STRONG EASTERLY FLOW CATCHES THE CYCLONE...AND FLOSSIE COULD
CURRENTLY BE AT OR VERY NEAR ITS PEAK INTENSITY. TO MAINTAIN SOME
CONTINUITY WITH THE PREVIOUS ADVISORY...THE INTENSITY FORECAST
ALLOWS FOR SLIGHT STRENGTHENING DURING THE DIURNAL CONVECTIVE
MAXIMUM LATER TONIGHT...AND THERE IS STILL A CHANCE FLOSSIE COULD
BECOME A HURRICANE. BY THE END OF THE FORECAST PERIOD...THE
EUROPEAN AND UKMET MODELS SHOW THE DEVELOPMENT OF SIGNIFICANT
WESTERLY SHEAR WHICH IS NOT SHOWN IN THE GFS. ACCORDINGLY...THE
OFFICIAL FORECAST IS BELOW THE GFS-BASED SHIPS MODEL.

THE PRIMARY STEERING MECHANISM CONTINUES TO BE A STRONG RIDGE
EXTENDING WESTWARD FROM MEXICO RESULTING IN A MOTION JUST SOUTH OF
DUE WEST OR 265/13. FLOSSIE IS EXPECTED TO MAINTAIN A WESTWARD TO
WEST-NORTHWESTWARD TRACK THROUGH THE FORECAST PERIOD AS A NARROW
RIDGE REMAINS NORTH OF THE CYCLONE. MODEL GUIDANCE IS GENERALLY
SPLIT INTO TWO CAMPS BASED ON THE EVENTUAL DEPTH AND STEERING OF
THE CYCLONE. THE NOGAPS AND EUROPEAN MODELS...BOTH OF WHICH SHOW A
WEAK VORTEX...LIE ON THE SOUTH SIDE OF THE MODEL SUITE.
CONVERSELY...THE GFDL AND HWRF MODELS...WHICH SHOW FLOSSIE BECOMING
A HURRICANE...LIE ON THE NORTH SIDE OF THE GUIDANCE ENVELOPE.
WHILE THE PRESENT TRENDS IN SATELLITE IMAGERY MAKE IT IS TEMPTING
TO LEAN TOWARDS THE WEAKER NOGAPS/EUROPEAN SOLUTION...IT IS TOO
SOON TO MAKE SUCH A SIGNIFICANT CHANGE TO THE TRACK FORECAST.
ACCORDINGLY...THE OFFICIAL FORECAST IS LARGELY UNCHANGED FROM THE
PREVIOUS ADVISORY.

FORECAST POSITIONS AND MAX WINDS

INITIAL 10/0300Z 12.6N 133.7W 55 KT
12HR VT 10/1200Z 12.7N 135.6W 60 KT
24HR VT 11/0000Z 13.0N 137.8W 60 KT
36HR VT 11/1200Z 13.4N 139.8W 60 KT
48HR VT 12/0000Z 13.8N 141.8W 55 KT
72HR VT 13/0000Z 14.5N 146.0W 55 KT
96HR VT 14/0000Z 15.5N 150.5W 50 KT
120HR VT 15/0000Z 16.5N 155.0W 40 KT

$$
FORECASTER RHOME

[RL3AO]

Hmm. Not forecasting a cane anymore.

[Derek Ortt]

different forecaster, different forecast. He is going with increasing shear and that the GFS is wrong (that would not be a surprise at all, it is the GFS afterall, my <sarcasm>favorite</sarcasm> model)

Personally, I believe this should become a cane by tomorrow

[RL3AO]

The CMC is my favorite. I think its forecasting Hurricane Pi here in the GOM next week.

[Cyclenall]

They did however keep it at 45 knots and call for a hurricane out of it which I agree on however if Flossie does something else, hurricane strength chance will slip away .

And we have this statement now:

THE INTENSITY FORECAST HAS
BECOME COMPLICATED BY THE DEVELOPMENT OF STRONG UPPER-LEVEL
EASTERLY FLOW NOW APPROACHING FLOSSIE FROM THE EAST.

Some dumb old shear .

[AnnularCane]

Leave her alone, Mr. Shear!

Looks like she's flaring a bit more.

[HURAKAN]

[Matt-hurricanewatcher]

If I had it I would bet 20 dollars this is now a hurricane based on latest satellite and 85h data. Very nice. 65 knots. HEHEHE

[HURAKAN]

The eye is becoming more visible now.

[Chacor]

We should be getting the 12Z fixes in a bit.

[HURAKAN]

249
WHXX01 KMIA 101240
CHGE77
TROPICAL CYCLONE GUIDANCE MESSAGE
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1240 UTC FRI AUG 10 2007

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

EAST PACIFIC OBJECTIVE AIDS FOR

TROPICAL CYCLONE FLOSSIE (EP092007) 20070810 1200 UTC

...00 HRS... ...12 HRS... ...24 HRS. .. ...36 HRS...
070810 1200 070811 0000 070811 1200 070812 0000

LAT LON LAT LON LAT LON LAT LON
BAMS 12.6N 135.4W 12.9N 137.6W 13.1N 139.7W 13.5N 141.6W
BAMD 12.6N 135.4W 12.8N 138.2W 12.9N 140.8W 13.1N 143.3W
BAMM 12.6N 135.4W 12.7N 138.0W 12.7N 140.5W 12.7N 142.8W
LBAR 12.6N 135.4W 12.9N 138.0W 13.9N 140.6W 14.8N 143.0W
SHIP 60KTS 66KTS 70KTS 72KTS
DSHP 60KTS 66KTS 70KTS 72KTS

...48 HRS... ...72 HRS... ...96 HRS. .. ..120 HRS...
070812 1200 070813 1200 070814 1200 070815 1200

LAT LON LAT LON LAT LON LAT LON
BAMS 13.7N 143.6W 14.7N 148.4W 16.6N 152.2W 18.4N 155.7W
BAMD 13.3N 145.6W 14.1N 150.4W 16.4N 154.2W 19.6N 155.7W
BAMM 12.8N 145.1W 13.2N 149.7W 14.2N 154.1W 15.6N 157.8W
LBAR 15.6N 145.2W 17.1N 148.4W 18.4N 150.5W 19.3N 151.6W
SHIP 70KTS 66KTS 59KTS 54KTS
DSHP 70KTS 66KTS 59KTS 54KTS

...INITIAL CONDITIONS...
LATCUR = 12.6N LONCUR = 135.4W DIRCUR = 270DEG SPDCUR = 12KT
LATM12 = 12.6N LONM12 = 133.1W DIRM12 = 268DEG SPDM12 = 12KT
LATM24 = 12.9N LONM24 = 130.4W
WNDCUR = 60KT RMAXWD = 15NM WNDM12 = 55KT
CENPRS = 990MB OUTPRS = 1010MB OUTRAD = 180NM SDEPTH = D
RD34NE = 45NM RD34SE = 60NM RD34SW = 45NM RD34NW = 45NM

$$
NNNN

The NHC may upgrade it to hurricane but models say 60 knots.

[Chacor]

I'm surprised models and ATCF initialise at 60 kt.

12Z fix from SAB is T4.0 (65 kt), 12Z TAFB fix is T4.5 (77 kt).

TAFB fix also notes eye.

EP, 09, 200708101200, 10, DVTS, CI, , 1260N, 13540W, , 1, 65, 3, , , , , , , , , , , , , , , , , , SAB, MT, I, 1, 4040 /////, , , GOES11, CSC, T,
EP, 09, 200708101200, 10, DVTS, CI, , 1270N, 13540W, , 1, 77, 2, , , , , , , , , , , , , , , , , , TAFB, MT, I, 1, 4545 /////, , , GOES11, CSC, T, DT = 5.0 BASED ON IR EYE PATTERN. NLINEEYE COLOR--

[HURAKAN]

The eye more visible than ever. If this is going to become a hurricane, 8 AM PDT will be its first opportunity.

[HURAKAN]

Looking good!!!

[Chacor]

WTPZ44 KNHC 101438
TCDEP4
HURRICANE FLOSSIE DISCUSSION NUMBER 8
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP092007
800 AM PDT FRI AUG 10 2007

INFRARED AND MICROWAVE IMAGERY INDICATE THAT FLOSSIE HAS
STRENGTHENED INTO A HURRICANE. AN EYE FEATURE HAS BECOME APPARENT
IN BOTH CONVENTIONAL AND SHORTWAVE INFRARED GOES IMAGERY...AND IN A
RECENT TRMM OVERPASS. THE OUTFLOW PATTERN CONTINUES TO
IMPROVE...PARTICULARLY OVER THE NORTHERN HALF OF THE CYCLONE... BUT
THE WESTERN PORTION IS RESTRICTED A BIT. DVORAK SATELLITE
INTENSITY ESTIMATES ARE 65 KT FROM SAB AND 77 KT FROM TAFB. THE
INITIAL INTENSITY IS INCREASED TO 65 KT...ON THE LOWER END OF THE
DVORAK ESTIMATES SINCE THE EYE FEATURE HAS BECOME LESS DISTINCT
SINCE 12Z.

SLIGHT STRENGTHENING IS EXPECTED DURING THE NEXT 24 HOURS WHILE
FLOSSIE REMAINS OVER SSTS GREATER THAN 27 CELSIUS. SSTS ALONG THE
FORECAST TRACK DECLINE THEREAFTER...SO GRADUAL WEAKENING IS
FORECAST BEYOND 36-48 HOURS. TOWARD THE END OF THE FORECAST
PERIOD...AN INCREASINGLY UNFAVORABLE ATMOSPHERIC
ENVIRONMENT...ESPECIALLY INDICATED BY THE EUROPEAN MODEL...AND
COOLER SEA SURFACE TEMPERATURES SHOULD INDUCE A CONTINUED WEAKENING
TREND. THE INTENSITY FORECAST IS ADJUSTED UPWARD TO REFLECT THE
CURRENT INTENSITY TREND...AND IS BASED ON A BLEND OF THE
SHIPS...ICON...SUPER-ENSEMBLE...AND THE LGE MODELS.

FLOSSIE IS MOVING AT 275/12...WITHIN THE DEEP EASTERLY FLOW AROUND A
RIDGE SITUATED TO THE NORTH OF THE SYSTEM. THE MAJORITY OF THE
GLOBAL MODELS SUGGEST A PERSISTENT WEST-NORTHWESTWARD TRACK...SOUTH
OF THE HAWAIIAN ISLANDS OVER THE NEXT 5 DAYS. THE GFDL...
HOWEVER...INDICATES A MORE NORTHWESTWARD MOTION BEYOND 24
HOURS...WHICH PLACES THE SYSTEM JUST TO THE NORTHEAST OF THE BIG
ISLAND ON DAY 5. ALTHOUGH THE GFDL SOLUTION CANNOT BE RULED
OUT...LESS EMPHASIS IS PLACED ON IT FOR NOW...BECAUSE A RIGHT OF
TRACK BIAS HAS BEEN IDENTIFIED IN PREVIOUS GFDL FORECASTS FOR
FLOSSIE. THE OFFICIAL FORECAST IS BASED ON A CONSENSUS OF THE
GLOBAL MODELS AND IS SLIGHTLY FASTER THAN THE PREVIOUS PACKAGE
AFTER THE 72 HOUR PERIOD.

FORECAST POSITIONS AND MAX WINDS

INITIAL 10/1500Z 12.7N 136.0W 65 KT
12HR VT 11/0000Z 12.8N 137.9W 65 KT
24HR VT 11/1200Z 13.1N 140.3W 70 KT
36HR VT 12/0000Z 13.5N 142.5W 70 KT
48HR VT 12/1200Z 13.9N 144.7W 65 KT
72HR VT 13/1200Z 14.9N 149.7W 60 KT
96HR VT 14/1200Z 16.5N 155.0W 55 KT
120HR VT 15/1200Z 18.0N 159.0W 45 KT

$$
FORECASTER ROBERTS/KNABB

[Derek Ortt]

6 hourly recon begins on Monday for Flossie at 18Z