Saison 2010 : Ouragans, cyclones, typhons, tempêtes et dépressions

[ElNino27 0]

Pourtant, on avait prévu de sales trucs. Je sais que la saison n'a pas encore vraiment commencé mais quand même ... Je m'ennuie

[paix 0]

Pas pour le Pacifique...

Pour l'Atlantique, c'est un tantinet poussif, mais pour l'instant, la saison n'est pas non plus "ennuyeuse" au regard de la climato.

D'ailleurs, Colin est en route sans doute :

ZCZC MIATWOAT ALL

TTAA00 KNHC DDHHMM

TROPICAL WEATHER OUTLOOK

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

200 PM EDT SUN AUG 1 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

1. A LARGE LOW PRESSURE SYSTEM CENTERED ABOUT 875 MILES WEST-SOUTHWEST

OF THE CAPE VERDE ISLANDS IS MOVING WESTWARD TO WEST-NORTHWESTWARD

AT 5 TO 10 MPH. SHOWER AND THUNDERSTORM ACTIVITY IS GRADUALLY

BECOMING BETTER ORGANIZED AND A TROPICAL DEPRESSION MAY BE FORMING.

IF THIS CURRENT DEVELOPMENT TREND CONTINUES...THEN ADVISORIES ON

THIS DISTURBANCE COULD BE INITIATED AS EARLY AS THIS AFTERNOON OR

EVENING. THERE IS A HIGH CHANCE...80 PERCENT...OF TROPICAL CYCLONE

FORMATION DURING THE NEXT 48 HOURS.

2. A WESTWARD-MOVING TROPICAL WAVE IS PRODUCING DISORGANIZED SHOWERS

AND THUNDERSTORMS OVER THE SOUTHWESTERN CARIBBEAN SEA AND ADJACENT

LAND AREAS OF CENTRAL AMERICA. UPPER-LEVEL WINDS REMAIN UNFAVORABLE

FOR ANY SIGNIFICANT DEVELOPMENT TO OCCUR BEFORE THE DISTURBANCE

MOVES ACROSS NICARAGUA AND HONDURAS IN THE NEXT DAY OR SO. THERE

IS A LOW CHANCE...10 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 STEWART/KIMBERLAIN

NNNN

Début de la saison capeverdienne probablement, et à partir de là, cela peut devenir très intéressant.

Modifié 1 août 2010 par paix

[paix 0]

Tiens, je pensais qui mettait un peu plus de temps à sortir les bulletins mensuels...

Si j'avais su, j'aurais attendu.

Pour le Pacifique Est, no comment

000

ABPZ30 KNHC 011436

TWSEP

MONTHLY TROPICAL WEATHER SUMMARY

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

800 AM PDT SUN AUG 01 2010

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

JULY WAS AN EXTREMELY INACTIVE MONTH IN THE EASTERN NORTH PACIFIC

BASIN WITH ONLY ONE TROPICAL DEPRESSION OBSERVED. THE LAST JULY IN

WHICH NO NAMED STORMS ARE KNOWN TO HAVE FORMED WAS IN 1966.

THE LONG-TERM AVERAGE FOR JULY IS THREE OR FOUR NAMED STORMS...

WITH TWO OF THE STORMS BECOMING HURRICANES...AND ONE OF THOSE

STRENGTHENING INTO A MAJOR HURRICANE.

THUS FAR FOR THE 2010 HURRICANE SEASON...THERE HAVE BEEN TWO

TROPICAL STORMS AND TWO HURRICANES...WITH BOTH OF THE HURRICANES

REACHING MAJOR HURRICANE INTENSITY. THESE NUMBERS ARE SLIGHTLY BELOW

THE LONG-TERM (1971-2009) AVERAGE OF ABOUT SIX TROPICAL STORMS...

AND NEAR THE AVERAGE OF THREE HURRICANES AND ONE OR TWO MAJOR

HURRICANES. IN TERMS OF ACCUMULATED CYCLONE ENERGY (ACE)...THE

OVERALL TROPICAL CYCLONE ACTIVITY OBSERVED SO FAR THIS SEASON IS

107 PERCENT OF THE LONG-TERM MEAN.

REPORTS ON INDIVIDUAL CYCLONES...WHEN COMPLETED...ARE AT THE WEB

SITE OF THE NATIONAL HURRICANE CENTER...USE LOWER-CASE LETTERS...

HTTP://WWW.NHC.NOAA.GOV/2010EPAC.SHTML

SUMMARY TABLE

NAME DATES MAX WIND (MPH)

-------------------------------------------------

TS AGATHA 29-30 MAY 45

TD TWO-E 16-17 JUN 30

TS BLAS 17-21 JUN 65

MH CELIA 19-29 JUN 160

MH DARBY 23-28 JUN 120

TD SIX-E 14-16 JUL 35

-------------------------------------------------

$$

FORECASTER STEWART/KIMBERLAIN/BEVEN

Après un mois de Juin en fanfare, qui a couvert l'activité pour le mois de Juin et Juillet si je puis dire, le Pacifique est retourné dans une léthargie qui risque de se poursuivre au moins jusqu'à la mi août.

Pour l'Atlantique, on fricote avec la moyenne, à l'exception qui l'aurait été plus "logique" de trouver Alex en Juillet et Bonnie en Juin :

00

ABNT30 KNHC 011134

TWSAT

MONTHLY TROPICAL WEATHER SUMMARY

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

800 AM EDT SUN AUG 01 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

TROPICAL DEPRESSION TWO AND TROPICAL STORM BONNIE FORMED DURING THE

MONTH OF JULY. IN ADDITION...ALEX DISSIPATED OVER MEXICO EARLY ON 2

JULY.

ON AVERAGE...ONE TROPICAL STORM FORMS IN THE ATLANTIC BASIN IN JULY.

SO FAR THIS SEASON...ONE TROPICAL STORM AND ONE HURRICANE HAVE

FORMED. THE OCCURRENCE OF TWO NAMED STORMS IS SIMILAR TO THE

LONG-TERM (1944-2009) AVERAGE...AND ONE HURRICANE IS A LITTLE

ABOVE THE LONG-TERM AVERAGE. IN TERMS OF ACCUMULATED CYCLONE ENERGY

(ACE)...OVERALL TROPICAL CYCLONE ACTIVITY OBSERVED TO DATE IS 111

PERCENT OF THE LONG-TERM MEAN.

REPORTS ON INDIVIDUAL CYCLONES...WHEN COMPLETED...ARE AT THE WEB

SITE OF THE NATIONAL HURRICANE CENTER...USE LOWER-CASE

LETTERS...HTTP://WWW.NHC.NOAA.GOV/2010ATLAN.SHTML

SUMMARY TABLE

NAME DATES MAX WIND (MPH)

----------------------------------------------------

H ALEX 25 JUN-2 JUL 105

TD TWO 7-8 JUL 35

TS BONNIE 22-24 JUL 40

$$

FORECASTER STEWART/BEVEN/KIMBERLAIN/PASCH

[ElNino27 0]

Eh ben hier soir, c'était faiblard, mais aujourd'hui, le truc s'est bien développé. Comme quoi, il ne faut jurer de rien avec les Tropiques ...

[paix 0]

Monté à 90%, sans doute la troisième dépression tout à l'heure avec les images visibles :

1. A LARGE AREA OF LOW PRESSURE LOCATED ABOUT 900 MILES WEST-SOUTHWEST

OF THE CAPE VERDE ISLANDS CONTINUES TO SHOW SIGNS OF ORGANIZATION

...BUT DOES NOT APPEAR TO HAVE A WELL-DEFINED SURFACE CENTER.

HOWEVER...CONDITIONS APPEAR FAVORABLE FOR ADDITIONAL DEVELOPMENT

AND A TROPICAL DEPRESSION COULD FORM AT ANY TIME DURING THE NEXT

COUPLE OF DAYS AS THIS SYSTEM MOVES WEST-NORTHWESTWARD AT 10 TO 15

MPH. THERE IS A HIGH CHANCE...90 PERCENT...OF TROPICAL CYCLONE

FORMATION DURING THE NEXT 48 HOURS.

[ElNino27 0]

Je ne suis pas sûr d'avoir déjà vu du 90%. Bientôt, on aura 95, 98, 99 ... 99,5 ... etc ...

La trajectoire serait ONO. Difficile de dire si le truc touchera les States.

[paix 0]

Je ne sais plus quand, mais ils ont déjà passé du 100%, et ils passent régulièrement du 0%. Mais je suis d'accord que cela fait un peu bizarre

ZCZC MIATWOAT ALL

TTAA00 KNHC DDHHMM

TROPICAL WEATHER OUTLOOK

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL

200 AM EDT MON AUG 2 2010

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

1. CLOUDINESS AND THUNDERSTORMS ASSOCIATED WITH A LARGE AREA OF LOW

PRESSURE LOCATED ABOUT 950 MILES WEST-SOUTHWEST OF THE CAPE VERDE

ISLANDS REMAIN FAIRLY WELL ORGANIZED...HOWEVER SATELLITE MICROWAVE

IMAGERY INDICATES THAT THE LOW DOES NOT YET HAVE A WELL-DEFINED

SURFACE CENTER OF CIRCULATION. NONETHELESS...CONDITIONS APPEAR

FAVORABLE FOR DEVELOPMENT AND A TROPICAL DEPRESSION COULD FORM AT

ANY TIME DURING THE NEXT DAY OR SO AS THIS SYSTEM MOVES

WEST-NORTHWESTWARD AT 10 TO 15 MPH. THERE IS A HIGH CHANCE...90

PERCENT...OF TROPICAL CYCLONE FORMATION DURING THE

NEXT 48 HOURS.

2. A TROPICAL WAVE APPROACHING THE COAST OF NICARAGUA IS PRODUCING

DISORGANIZED SHOWERS AND THUNDERSTORMS OVER THE SOUTHWESTERN

CARIBBEAN SEA AND ADJACENT LAND AREAS. SIGNIFICANT DEVELOPMENT OF

THIS DISTURBANCE IS UNLIKELY BEFORE IT MOVES INLAND LATER TODAY...

AND THERE IS A LOW CHANCE...NEAR 0 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

NNNN

[paix 0]

Le système semble bien présenté en visible,

le dernier Dvorak Number monte à2 :

Atlantic Ocean Basin: Imagery

DATE/TIME LAT LON CLASSIFICATION STORM

02/1145 UTC 12.7N 39.8W T2.0/2.0 91L

02/0545 UTC 10.2N 38.7W T1.5/1.5 91L

01/2345 UTC 10.0N 37.8W T1.5/1.5 91L

01/1800 UTC 9.7N 36.6W T1.5/1.5 91L

01/1200 UTC 8.7N 34.4W T1.5/1.5 91L

30/1145 UTC 8.9N 31.4W TOO WEAK 90L

30/0545 UTC 8.2N 31.6W T1.0/1.0 90L

30/0000 UTC 8.0N 31.5W T1.0/1.0 90L

Bref, l'upgrade devrait être fait tout à l'heure en fin de matinée locale (20 heures chez nous).

[paix 0]

Ils viennent finalement d'en faire la TD 4:

000

WTNT34 KNHC 021435

TCPAT4

BULLETIN

TROPICAL DEPRESSION FOUR ADVISORY NUMBER 1

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

1100 AM EDT MON AUG 02 2010

...NEW TROPICAL DEPRESSION FORMS IN THE ATLANTIC...

SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION

-----------------------------------------------

LOCATION...12.6N 41.1W

ABOUT 1365 MI...2200 KM E OF THE LESSER ANTILLES

MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/HR

PRESENT MOVEMENT...WNW OR 290 DEGREES AT 17 MPH...28 KM/HR

MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

WATCHES AND WARNINGS

--------------------

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

DISCUSSION AND 48-HOUR OUTLOOK

------------------------------

AT 1100 AM EDT...1500 UTC...THE CENTER OF TROPICAL DEPRESSION FOUR

WAS LOCATED NEAR LATITUDE 12.6 NORTH...LONGITUDE 41.1 WEST. THE

DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 17 MPH...28

KM/HR. A CONTINUED MOTION TOWARD THE WEST-NORTHWEST WITH AN

INCREASE IN FORWARD SPEED IS EXPECTED OVER THE NEXT COUPLE OF DAYS.

MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH...55 KM/HR...WITH HIGHER

GUSTS. SOME STRENGTHENING IS FORECAST DURING THE NEXT 48 HOURS...

AND THE DEPRESSION COULD BECOME A TROPICAL STORM BY TONIGHT OR

TUESDAY.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB...29.71 INCHES.

HAZARDS AFFECTING LAND

----------------------

NONE

NEXT ADVISORY

-------------

NEXT COMPLETE ADVISORY...500 PM EDT.

$$

FORECASTER BRENNAN

[ElNino27 0]

26% de chances d'avoir un ouragan dans 3 jours. Les Bermudes pourraient être touchées, mais sa trajectoire semble trop courbe pour aller vers les USA.

[paix 0]

Et voici donc Colin , toujours une chance sur quatre de voir un ouragan d'après le NHC :

000

WTNT44 KNHC 030831

TCDAT4

TROPICAL STORM COLIN DISCUSSION NUMBER 4

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

500 AM EDT TUE AUG 03 2010

THE TROPICAL CYCLONE HAS BECOME BETTER ORGANIZED OVER THE PAST

SEVERAL HOURS. ENHANCED INFRARED SATELLITE IMAGES SHOW A CURVED

BAND WRAPPING HALFWAY AROUND THE CIRCULATION OVER THE WESTERN

SEMICIRCLE. DVORAK DATA T-NUMBERS ARE 2.5 FROM BOTH TAFB AND SAB

SUPPORTING A CURRENT INTENSITY ESTIMATE OF 35 KT. THEREFORE THE

SYSTEM IS BEING NAMED AT THIS TIME. COLIN IS EXPECTED TO BE IN AN

ENVIRONMENT CONDUCIVE FOR SOME STRENGTHENING...WITH MODERATE TO

WEAK VERTICAL SHEAR AND ANTICYCLONIC UPPER-LEVEL FLOW...FOR THE

NEXT 36 HOURS OR SO. THEREAFTER...INCREASING WESTERLY SHEAR

ASSOCIATED WITH AN UPPER-LEVEL LOW OVER THE SOUTHWESTERN NORTH

ATLANTIC SHOULD BEGIN TO IMPACT THE STORM. THE OFFICIAL FORECAST

CALLS FOR MODEST STRENGTHENING DURING THE NEXT 36 HOURS FOLLOWED BY

A LEVELING OFF OF INTENSITY THEREAFTER. THIS IS SIMILAR TO THE

LATEST GFDL MODEL FORECAST AND NOT TOO DISSIMILAR TO THE PREVIOUS

NHC FORECAST. NONE OF THE DYNAMICAL OR STATISTICAL/DYNAMICAL

INTENSITY GUIDANCE BRINGS COLIN TO HURRICANE STRENGTH OVER THE NEXT

5 DAYS.

CENTER FIXES SHOW THAT THE STORM CONTINUES TO MOVE BRISKLY TOWARD

THE WEST-NORTHWEST...AND THE INITIAL MOTION ESTIMATE REMAINS AT

285/20. AT THIS TIME...THE STEERING FOR COLIN IS BEING PROVIDED DUE

TO A SUBTROPICAL RIDGE TO THE NORTH AND A LOW- TO MID-TROPOSPHERIC

EASTERLY JET. THIS RELATIVELY FAST STEERING CURRENT SHOULD MORE OR

LESS PREVAIL FOR THE NEXT COUPLE OF DAY OR SO. THEREAFTER...THE

TROPICAL CYCLONE IS LIKELY TO APPROACH A WEAKNESS IN THE

SUBTROPICAL RIDGE. THIS WOULD CAUSE A GRADUAL TURN TO THE RIGHT

ALONG WITH A DECREASING FORWARD SPEED. THE TRACK GUIDANCE MODELS

ARE IN FAIRLY GOOD AGREEMENT OVER THE NEXT 36 HOURS. AFTER THAT

FORECAST TIME...THE MODELS BECOME MODERATELY DIVERGENT WITH THE GFS

AND ECMWF ON THE LEFT SIDE OF THE GUIDANCE ENVELOPE AND THE GFDL

AND HWRF ON THE RIGHT. THE OFFICIAL TRACK FORECAST IS ROUGHLY IN

THE MIDDLE OF THE ENVELOPE...FAIRLY CLOSE TO THE DYNAMICAL MODEL

CONSENSUS...AND VERY CLOSE TO THE PREVIOUS NHC FORECAST.

OBSERVATIONS FROM NOAA DATA BUOY 41041 OVER THE CENTRAL TROPICAL

ATLANTIC INDICATE THAT COLIN IS A SMALL TROPICAL STORM...AND THE

WIND RADII SHOWN IN THE ADVISORY MIGHT BE GENEROUS.

INTERESTS IN THE NORTHERN LEEWARD ISLANDS SHOULD FOLLOW THE PROGRESS

OF COLIN. AT THIS TIME...BASED ON THE FORECAST TRACK...WIND

FIELD...AND REASONABLE UNCERTAINTIES...NO TROPICAL STORM WATCHES OR

WARNINGS ARE REQUIRED.

FORECAST POSITIONS AND MAX WINDS

INITIAL 03/0900Z 14.0N 47.2W 35 KT

12HR VT 03/1800Z 15.1N 50.3W 40 KT

24HR VT 04/0600Z 16.8N 54.5W 45 KT

36HR VT 04/1800Z 18.6N 58.3W 50 KT

48HR VT 05/0600Z 20.6N 61.5W 50 KT

72HR VT 06/0600Z 24.5N 66.5W 50 KT

96HR VT 07/0600Z 28.0N 68.5W 50 KT

120HR VT 08/0600Z 31.0N 69.5W 50 KT

$$

FORECASTER PASCH

[ElNino27 0]

Paraît que l'ex-général n'est pas en très bonne santé. Le NHC se demande même s'il y a encore "closed" circulation. Vaut mieux pas trop se prononcer avant qu'il récupère éventuellement de la vigueur, le bougre.

[paix 0]

Tiens effectivement, ce cher général Colin P.

Je ne pensais à personne avec ce nom de Colin, mais maintenant que vous le dites, pourquoi pas

Je copie colle la prose du NHC, c'est mieux qu'un long discours :

Tropical Storm COLIN Forecast Discussion

Home Public Adv Fcst/Adv Discussion Wind Probs Maps/Charts Archive

000

WTNT44 KNHC 032043

TCDAT4

TROPICAL STORM COLIN DISCUSSION NUMBER 6

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

500 PM EDT TUE AUG 03 2010

THE CENTER OF COLIN PASSED NEAR OR OVER THE WOODS HOLE NTAS BUOY

ABOUT 15Z...WHICH REPORTED A MINIMUM PRESSURE OF 1007 MB AND A

SMALL LOW PRESSURE CENTER. HOWEVER...NEITHER THAT BUOY NOR THE

NEARBY NOAA BUOY 41040 REPORTED WINDS SUPPORTING A CLOSED

CIRCULATION...AND WESTERLY WINDS ARE NOT CURRENTLY APPARENT IN LOW

CLOUD MOTIONS SOUTH OF THE CENTER. ADDITIONALLY...THE ASSOCIATED

CONVECTION HAS BECOME VERY DISORGANIZED. BASED ON THIS...COLIN HAS

DEGENERATED INTO A REMNANT LOW WITH GALE-FORCE WINDS OVER A SMALL

AREA NORTH OF THE CENTER.

IN THE SHORT TERM...REGENERATION APPEARS UNLIKELY AS THE REMNANTS OF

COLIN ENCOUNTER WESTERLY VERTICAL SHEAR CAUSED BY THE STRONG

LOW-LEVEL FLOW AND WESTERLY WINDS ASSOCIATED WITH A COMPLEX

UPPER-LEVEL TROUGH OVER THE SOUTHWESTERN ATLANTIC. HOWEVER...NONE

OF THE DYNAMICAL MODELS FORECAST THE REMNANTS OF COLIN TO DISSIPATE

DURING THE FORECAST PERIOD...AND THEY FORECAST THAT THE SYSTEM

COULD REACH A MORE FAVORABLE ENVIRONMENT OFF THE SOUTHEASTERN COAST

OF THE UNITED STATES BY DAY 5. BASED ON THIS...THE INTENSITY

FORECAST CALLS FOR THE REMNANTS OF COLIN TO DROP BELOW GALE FORCE

DURING THE NEXT 12 HR AND CONTINUE AS A 30 KT REMNANT LOW THROUGH

96 HR. AFTER THAT...THE DISTURBANCE COULD REGENERATE INTO A

TROPICAL CYCLONE AS SHOWN IN THE 120-HR FORECAST.

THE INITIAL MOTION IS AN EXTREMELY RAPID 285/30. ALL GUIDANCE

AGREES THAT THE REMNANTS OF COLIN SHOULD CONTINUE WEST-

NORTHWESTWARD FOR THE NEXT 48-72 HR WITH A SIGNIFICANT DECREASE IN

FORWARD SPEED. THE NEW FORECAST TRACK IS SIMILAR IN DIRECTION TO

THE PREVIOUS FORECAST...BUT IS MUCH FASTER. AFTER THAT TIME...THE

SYSTEM SHOULD TURN NORTHWESTWARD INTO A BREAK IN THE SUBTROPICAL

RIDGE NEAR THE EASTERN COAST OF THE UNITED STATES. MOST OF THE

DYNAMICAL MODELS HAVE SHIFTED THEIR 96-120 HR FORECASTS WESTWARD...

AND THE OFFICIAL FORECAST WILL DO LIKEWISE.

INTERESTS IN THE NORTHERN LEEWARD ISLANDS AND THE VIRGIN ISLANDS

SHOULD FOLLOW THE PROGRESS OF THE REMNANTS OF COLIN.

THIS IS THE LAST ADVISORY ISSUED BY THE NATIONAL HURRICANE CENTER ON

THIS SYSTEM UNLESS REGENERATION OCCURS. ADDITIONAL INFORMATION ON

THIS SYSTEM CAN BE FOUND IN HIGH SEAS FORECASTS ISSUED BY THE

NATIONAL WEATHER SERVICE...UNDER AWIPS HEADER NFDHSFAT1 AND WMO

HEADER FZNT01 KWBC.

FORECAST POSITIONS AND MAX WINDS

INITIAL 03/2100Z 15.8N 53.8W 35 KT...POST-TROP/REMNT LOW

12HR VT 04/0600Z 16.8N 57.2W 30 KT...POST-TROP/REMNT LOW

24HR VT 04/1800Z 18.4N 60.8W 30 KT...POST-TROP/REMNT LOW

36HR VT 05/0600Z 20.0N 63.8W 30 KT...POST-TROP/REMNT LOW

48HR VT 05/1800Z 21.7N 66.5W 30 KT...POST-TROP/REMNT LOW

72HR VT 06/1800Z 25.0N 70.0W 30 KT...POST-TROP/REMNT LOW

96HR VT 07/1800Z 28.0N 72.5W 30 KT...POST-TROP/REMNT LOW

120HR VT 08/1800Z 30.0N 73.5W 30 KT...TROPICAL DEPRESSION

$$

FORECASTER BEVEN

Modifié 4 août 2010 par paix

[ElNino27 0]

Comme quoi, il ne faut jamais être sûr de rien avec les cyclones.

On dirait qu'il y a une possibilité en mer des Caraïbes ...

[paix 0]

C'est d'un ennui mortel cette année. Encore pire que l'année dernière je trouve. Même l'activité cyclonique du Pacifique Ouest est parti en vacances je ne sais où. "Heuresement" que Colin n'a pas atteint le statut d'ouragan sinon l'Atlantique aurait conservé son avance sur les totaux du Pacifique Ouest....

[ElNino27 0]

Eh ben le générallissime pourrait bien renaître, selon le NHC. 70% de chances et un LLC en voie de reformation.

[paix 0]

En effet, il vient de faire un retour en force. Si il passe le seuil des 65 nœuds, l'Atlantique reprend la main au Pacifique Ouest

000

WTNT44 KNHC 060001

TCDAT4

TROPICAL STORM COLIN SPECIAL DISCUSSION NUMBER 8

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

730 PM AST THU AUG 05 2010

...THIS SPECIAL ADVISORY HAS BEEN ISSUED TO PRIMARILY UPDATE THE

INTENSITY AND WIND RADII FORECASTS.

SHORTLY AFTER THE PREVIOUS ADVISORY HAD BEEN ISSUED...AN AIR FORCE

RESERVE RECONNAISSANCE AIRCRAFT INVESTIGATING TROPICAL STORM COLIN

REPORTED A 600-FT FLIGHT-LEVEL WIND OF 71 KT ABOUT 14 NMI NORTHEAST

OF THE CIRCULATION CENTER. IN ADDITION...A SURFACE PRESSURE OF 1005

MB WAS ALSO OBSERVED IN THE GENERAL VICINITY. IT IS UNCERTAIN IF

THESE VALUES WERE ASSOCIATED WITH A SMALL MESOVORTEX LOCATED

NORTHEAST OF THE CENTER...WHICH WOULD NOT BE REPRESENTATIVE OF THE

LARGER-SCALE WIND FIELD. FOR THIS REASON...THE INTENSITY WAS

INITIALIZED AT 40 KT IN AGREEMENT WITH NEARBY SFMR WINDS.

HOWEVER...SINCE THE TIME OF THAT RECON REPORT...DEEP CONVECTION IN

THE NORTHEASTERN QUADRANT OF COLIN HAS CONTINUED TO DEVELOP CLOSER

TO THE LOW-LEVEL CIRCULATION CENTER...WHICH JUSTIFIES INCREASING

THE INTENSITY TO 50 KT BASED ON A BLEND OF THE FLIGHT-LEVEL WINDS

AND SFMR SURFACE WINDS. SINCE A FORECAST INTENSITY OF 50 KT WAS NOT

EXPECTED TO OCCUR UNTIL 48 HOURS IN THE PREVIOUS ADVISORY...A

SPECIAL ADVISORY WAS REQUIRED TO INCREASE THE INTENSITY AND TO

ADJUST THE INTENSITY FORECAST UPWARD DURING THE NEXT 36 HOURS.

ALSO...DROPSONDE DATA INDICATES AN EXPANSION OF THE 34-KT WIND

RADII IN THE SOUTHEASTERN QUADRANT WAS NECESSARY.

NO SIGNIFICANT CHANGES TO THE PREVIOUS TRACK FORECAST OR REASONING

WERE MADE.

INTERNET PROBLEMS WILL PREVENT THE NHC WEB SITE FROM BEING UPDATED

AT THIS TIME. PLEASE SEE WEATHER.GOV FOR ADVISORY TEXT PRODUCTS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 05/2330Z 25.6N 66.3W 50 KT

12HR VT 06/0600Z 26.6N 67.1W 50 KT

24HR VT 06/1800Z 28.1N 67.3W 50 KT

36HR VT 07/0600Z 29.6N 67.3W 50 KT

48HR VT 07/1800Z 31.3N 67.1W 55 KT

72HR VT 08/1800Z 36.0N 65.0W 55 KT

96HR VT 09/1800Z 40.0N 61.5W 60 KT

120HR VT 10/1800Z 49.0N 48.0W 50 KT...POST-TROP/EXTRATROP

$$

FORECASTER STEWART/BROWN

Par contre le centre est totalement exposé :

[ElNino27 0]

Rare d'avoir une renaissance ... la dernière fois : Katrina !

[paix 0]

Mouais, bah c'est pas la grande forme

000

WTNT44 KNHC 060345

TCDAT4

TROPICAL STORM COLIN DISCUSSION NUMBER 9

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

1100 PM AST THU AUG 05 2010

COLIN HAS MAINTAINED A SATELLITE CLOUD SIGNATURE SIMILAR TO WHEN A

RECONNAISSANCE AIRCRAFT INVESTIGATED THE SYSTEM 6 HOURS AGO. SINCE

THEN...A STRONG BURST OF DEEP CONVECTION HAS DEVELOPED IN THE

NORTHEASTERN QUADRANT...ALTHOUGH THE CONVECTION HAS WANED A LITTLE

DURING THE PAST COUPLE OF HOURS. HOWEVER...THE STRONG PRESSURE

GRADIENT IN THE EASTERN SEMICIRCLE BETWEEN THE CENTER OF COLIN AND

NOAA BUOY 41049 LOCATED 225 NMI TO THE NORTHEAST SUPPORTS KEEPING

THE INTENSITY AT 50 KT.

THE INITIAL MOTION ESTIMATE IS 340/12. THERE IS NO SIGNIFICANT

CHANGE TO THE PREVIOUS FORECAST TRACK OR REASONING. COLIN IS

EXPECTED TO GRADUALLY SLOW DOWN AND TURN NORTHWARD TOWARD A

DEVELOPING WEAKNESS IN THE SUBTROPICAL RIDGE OVER THE NEXT 48

HOURS...AND THEN RECURVE TO THE NORTHEAST OVER THE NORTH ATLANTIC

BY 72 HOURS AHEAD OF AN EASTWARD-MOVING MID-LATITUDE SHORTWAVE

TROUGH CURRENTLY MOVING ACROSS GREAT LAKES AND OHIO VALLEY REGIONS.

THE MODELS REMAIN IN GOOD AGREEMENT ON THIS SCENARIO...AND THE

FORECAST TRACK WAS ONLY NUDGED SLIGHTLY TO THE EAST THROUGH 48

HOURS DUE TO THE MORE EASTWARD INITIAL POSITION. COLIN IS EXPECTED

TO PASS JUST WEST OF BERMUDA IN 36-48 HOURS...BUT ONLY A SLIGHT

DEVIATION TO THE EAST COULD BRING THE CENTER OVER BERMUDA.

SOUTHWESTERLY VERTICAL SHEAR OF 20-25 KT CONTINUES TO HINDER

SIGNIFICANT INTENSIFICATION OF COLIN...AND THESE UNFAVORABLE

CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THE NEXT 24 HOURS.

HOWEVER...FROM 36 TO 48 HOURS...ALL OF THE GLOBAL MODELS ARE

FORECASTING THE VERTICAL SHEAR TO WEAKEN SIGNIFICANTLY AS COLIN

PASSES BETWEEN TWO UPPER-LEVEL LOWS AND MOVES UNDER A SMALL

RIDGE...WHICH PROVIDES A BRIEF WINDOW OF OPPORTUNITY FOR COLIN TO

STRENGTHEN. THE SHIPS AND LGEM MODELS BRING COLIN TO NEAR 60 KT BY

48 HOURS...WHEN THE CYCLONE IS NEAR BERMUDA...AND THIS TREND WAS

FOLLOWED FOR THIS ADVISORY PACKAGE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/0300Z 26.3N 66.6W 50 KT

12HR VT 06/1200Z 27.4N 66.9W 50 KT

24HR VT 07/0000Z 29.1N 67.0W 50 KT

36HR VT 07/1200Z 30.7N 66.8W 55 KT

48HR VT 08/0000Z 32.6N 66.1W 60 KT

72HR VT 09/0000Z 37.2N 63.5W 60 KT

96HR VT 10/0000Z 43.0N 57.0W 55 KT

120HR VT 11/0000Z 50.5N 45.0W 50 KT...POST-TROP/EXTRATROP

$$

FORECASTER STEWART

Par contre le Pacifique Ouest vient de décommater, après 40 jours de blanc :

000

WTPZ42 KNHC 060300

TCDEP2

TROPICAL DEPRESSION SEVEN-E DISCUSSION NUMBER 1

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072010

800 PM PDT THU AUG 05 2010

CONVENTIONAL AND MICROWAVE SATELLITE DATA SHOW THAT THE SMALL LOW

PRESSURE AREA OFF THE SOUTHERN COAST OF MEXICO HAS BECOME BETTER

DEFINED AND HAS ACQUIRED ENOUGH ORGANIZATION TO BE DECLARED A

TROPICAL CYCLONE. THE LATEST DVORAK T-NUMBERS FROM SAB AND TAFB

WERE 2.5...WHICH SUPPORT TROPICAL STORM STRENGTH. HOWEVER...THE

CONVECTIVE TOPS HAVE WARMED SINCE 0000 UTC...SO THE INITIAL

INTENSITY IS SET AT A PERHAPS CONSERVATIVE 30 KT.

THE INITIAL MOTION ESTIMATE IS 290/9. THE DEPRESSION IS LOCATED TO

THE SOUTH OF A MID- TO UPPER-LEVEL RIDGE OVER THE SOUTH-CENTRAL

UNITED STATES AND NORTHERN MEXICO. THIS SHOULD ALLOW THE

DEPRESSION TO MOVE IN A GENERAL WEST-NORTHWESTWARD DIRECTION DURING

THE NEXT COUPLE OF DAYS. THE GLOBAL MODELS DID NOT INITIALIZE THE

SMALL CYCLONE VERY WELL AND MANY OF THEM SHOW THE CYCLONE

INTERACTING WITH ITCZ DISTURBANCES TO THE SOUTH OF THE DEPRESSION.

THIS RESULTS IN MANY OF THE GLOBAL MODELS PREDICTING A SLOWER AND

MORE ERRATIC TRACK DURING THE NEXT FEW DAYS. THIS SCENARIO SEEMS

UNREALISTIC AT THIS TIME. GIVEN THE STRONG RIDGE TO THE

NORTH...THE OFFICIAL FORECAST SHOWS A WEST-NORTHWEST TRACK THAT

IS IN BEST AGREEMENT WITH THE BAM MEDIUM AND HWRF MODELS THROUGH 72

HOURS. AFTER THAT TIME...THE CYCLONE SHOULD BE APPROACHING A

WEAKNESS IN THE RIDGE WEST OF THE BAJA PENINSULA WHICH WILL LIKELY

CAUSE THE CYCLONE TO DECELERATE. DUE TO THE UNUSUALLY LARGE SPREAD

IN THE GUIDANCE THE CONFIDENCE IN THE TRACK FORECAST IS LOWER THAN

NORMAL.

UPPER-LEVEL WINDS ARE FORECAST TO REMAIN CONDUCIVE FOR

INTENSIFICATION DURING THE NEXT 2-3 DAYS. THE OFFICIAL FORECAST

CALLS FOR STEADY STRENGTHENING THROUGH 48 HOURS AND THIS IS AT THE

UPPER-END OF THE INTENSITY GUIDANCE. AFTER 72 HOURS...THE CYCLONE

IS EXPECTED TO BEGIN MOVING OVER COOLER WATER WHICH SHOULD INDUCE

WEAKENING.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/0300Z 16.0N 102.1W 30 KT

12HR VT 06/1200Z 16.4N 103.5W 40 KT

24HR VT 07/0000Z 17.0N 105.2W 50 KT

36HR VT 07/1200Z 17.7N 106.9W 55 KT

48HR VT 08/0000Z 18.5N 108.5W 60 KT

72HR VT 09/0000Z 19.7N 110.8W 60 KT

96HR VT 10/0000Z 20.7N 113.0W 45 KT

120HR VT 11/0000Z 21.5N 115.0W 30 KT

$$

FORECASTER BROWN

J'avoue que j'ai un peul à voir où êut être le centre :

[paix 0]

Pour le Pacifique Est, le creux qui a donné naissance à la dépression Sept venait d'une onde tropicale qui avait été surveillé par le NHC dans les Caraïbes déjà. Je ne pensais pas qu'elle pourrait se développer dans le Pacifique, mea culpa. Par contre je maintiens qu'il n'y a pas grand chose à attendre de ce début de mois d'Août, et TD7, sans doute tempête tropicale Estelle à court terme, sera sans doute le seul représentant de son espèce pour le Pacifique Est pour ces deux premières semaines.

Par contre, l'Atlantique commence à se secouer apparemment. Une nouvelle onde se développe en plein cœur de l'Atlantique. Colin a pal mal souffert, et est toujours en galère, mais il a sans doute ouvert la voie au début de la saison des ouragans capeverdiens, les plus beaux spécimens de cyclone tropicaux que peut nous produire l'Atlantique. Si lui est passé, c'est que les conditions deviennent suffisamment clémentes pour que d'autres suivent. Cependant, si cette hypothèse du début de la "saison capverdienne" (faut pas chercher, cette expression n'existe pas ), cela hypothèque autant la sortie du Pacifique Est de sa léthargie.

Sur les cartes de cisaillement de vent, on note bien l'apparition de ce boulevard bleu/noir entre 10° et 20° Nord, qui dénote un faible cisaillement de vent favorable à la cyclogenèse extratropicale.

Cette onde, nom de code 93L pour les intimes est en code orange, 40% de proba. Elle est presque une tête de creux de mousson, avec ce "big mess" caractéristique. Évidemment, niveau organisation, ce n'est pas gagné, mais la convection pousse pas mal et il y a un embryon de circulation en surface avec une grosse convergence qui commence à se courber.

L'image visible de groupe (ils n'ont pas encore mis de floater pour un zoom dessus), avec Colin au Nord Ouest, et cet amas nuageux par 10°N/15°N et 35°O/40°O.

On pourra noter plus au Nord que les traditionnels stratocumulus sous l'inversion de l'anticyclone des Açores sont franchement faiblards, et dénote la présence d'un air sec. De plus sur l'image visible, on note un creux d'altitude (Upper Level Trough en anglais) à l'Est de Colin qui le cisaille fortement. Je ne savais pas comment le mettre en évidence, il apparait dans les tons noir bruns à l'Est de Colin avec une faible virgule blanche. Cependant, il ne s'agit pas de la bande brun en avant de 93L qui dénote elle la présence d'une couche d'air saharienne (Saharian Air Layer en anglais). Bref, tous ce bazar pour dire que Colin est cisaillé, et que dans l'immédiat, 93L a les fesses dans la chaleur moite des tropiques. Bref, le bonheur

Venons en à Colin justement, ce cher bougre est totalement cisaillé, découplé, dépecé, dépiauté, mais toujours bien vivant.

Le cisaillement d'Est associé se visualise bien. Le centre est magnifiquement exposé, mais la circulation reste fermé, et la convection pulse. En effet, il existe deux autre creux d'altitude, dont l'un est nettement visible sur l'image satellite. Il s'agit de la virgule blanche à l'avnat de Colin. Il existe un dernier creux plus au Nord, mais non visible. Bref, pris dans cette chienlit, Colin se fait cisaillé, mais il profite à fond de la divergence d'altitude associé au flux de sortie du creux qui est à l'Ouest de sa position (la deuxième virgule blanche, si certains ne suivent plus ), et donc, la chemine tire, mais la convection ne bande pas.

000

WTNT44 KNHC 060838

TCDAT4

TROPICAL STORM COLIN DISCUSSION NUMBER 10

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL042010

500 AM AST FRI AUG 06 2010

VERTICAL WIND SHEAR...ANALYZED AT 25 KT BY THE SHIPS MODEL...HAS

AGAIN TAKEN A TOLL ON COLIN...WITH THE LOW-LEVEL CENTER NOW

COMPLETELY EXPOSED TO THE WEST OF THE PULSING DEEP CONVECTION. AN

ASCAT PASS AROUND 0118 UTC SHOWED SEVERAL 35-40 KT RETRIEVALS EAST

OF THE CENTER...AND THE INITIAL INTENSITY IS LOWERED TO 40 KT FOR

THIS ADVISORY. THE SHIPS MODEL SHOWS THE SHEAR DECREASING TO LESS

THAN 10 KT IN 24 HOURS...WHICH SHOULD GIVE COLIN AN OPPORTUNITY TO

RE-INTENSIFY. HOWEVER...THE SHEAR INCREASES RAPIDLY AGAIN BY 48

HOURS...WHICH SHOULD LIMIT INTENSIFICATION BEYOND THAT TIME. THE

OFFICIAL INTENSITY FORECAST IS ADJUSTED DOWNWARD TOWARD THE ICON

INTENSITY CONSENSUS THROUGH 48 HOURS AND IS SIMILAR TO THE PREVIOUS

PACKAGE AFTER THAT.

THE 12-HOUR INITIAL MOTION ESTIMATE IS 325/12...TO THE LEFT OF THE

PREVIOUS TRACK FORECAST. COLIN IS SITUATED TO THE SOUTHEAST OF AN

UPPER-LEVEL SHEAR AXIS ANCHORED BY ONE LOW CENTER NEAR 27N 75W AND

ANOTHER NEAR BERMUDA. THE GLOBAL MODELS SUGGEST THAT THESE LOWS

WILL MOVE AWAY AND ALLOW COLIN TO MOVE NORTHWARD AT A SLOWER SPEED

INTO A BREAK IN THE SUBTROPICAL RIDGE OVER THE NEXT COUPLE OF DAYS.

BEYOND THAT TIME...THE GLOBAL MODELS SHOW A LONGWAVE TROUGH

ADVANCING EASTWARD ACROSS THE NORTHEASTERN U.S. AND EASTERN

CANADA. HOWEVER...THE TIMING OF THE INTERACTION BETWEEN COLIN AND

INDIVIDUAL SHORTWAVES IN THE TROUGH VARIES WIDELY IN THE

GUIDANCE...AND SO DOES THE FORWARD SPEED AND TRACK OF THE CYCLONE.

THE GFS...ECMWF...AND GFDL MOVE COLIN MORE SLOWLY AND DELAY

INTERACTION WITH THE TROUGH UNTIL AROUND DAY 4...WHILE THE UKMET...

NOGAPS...AND HWRF TAKE COLIN MORE QUICKLY NORTHWARD AND SHOW

INTERACTION WITH THE TROUGH ABOUT A DAY EARLIER. GIVEN THAT

THE 72-HOUR FORECAST POSITIONS FROM THE GFS AND NOGAPS ARE ABOUT

1000 MILES APART...THIS TRACK FORECAST HAS LOW CONFIDENCE...

ESPECIALLY IN THE LATER PERIODS. THE OFFICIAL FORECAST HAS BEEN

ADJUSTED TO THE LEFT OF THE PREVIOUS NHC TRACK THROUGH 48 HOURS DUE

TO THE MORE WESTERLY INITIAL POSITION AND MOTION...AND LIES ALONG

THE LEFT SIDE OF THE GUIDANCE ENVELOPE. BEYOND THAT TIME...THE

BIGGEST CHANGE TO THE OFFICIAL FORECAST WAS TO SLIGHTLY DECREASE THE

FORWARD SPEED DUE TO THE LARGE SPREAD IN THE GUIDANCE. ONE

ALTERNATIVE SCENARIO IS THAT IF COLIN REMAINS A SHALLOW SYSTEM

WITHOUT MUCH DEEP CONVECTION...IT COULD MOVE FARTHER TO THE LEFT

AND MORE SLOWLY IN THE SHORT TERM ALONG A TRACK SIMILAR TO THE

SHALLOW BAM.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/0900Z 26.8N 67.4W 40 KT

12HR VT 06/1800Z 27.9N 67.7W 40 KT

24HR VT 07/0600Z 29.8N 67.4W 45 KT

36HR VT 07/1800Z 31.5N 66.8W 50 KT

48HR VT 08/0600Z 33.6N 65.7W 55 KT

72HR VT 09/0600Z 38.5N 62.5W 60 KT

96HR VT 10/0600Z 44.0N 56.0W 55 KT

120HR VT 11/0600Z 50.5N 45.0W 50 KT...POST-TROP/EXTRATROP

$$

FORECASTER BRENNAN

Modifié 6 août 2010 par paix

[paix 0]

Tiens, j'avais raté cela :

http://www.cpc.noaa.gov/products/outlooks/hurricane.shtml

Je l'ai lu en diagonale vite fait, mais apparemment, pas grand'chose n'a changé depuis Mai. La Nina, les SSTs de l'Atlantique, ...

Sont juste un peu réduit la fourchette vu que le début de saison est poussif.

Le TSR a fait aussi son update, là j'avoue je n'ai même pas lu, mais je pense pas qu'ils aient changé grand'chose.

http://www.tropicalstormrisk.com/docs/TSRA...castAug2010.pdf

Modifié 6 août 2010 par paix

[paix 0]

Un avion est parti rendre une petite visite à Colin. Je suis curieux de savoir ce qu'il va trouver, car il semblerait que le centre reviennent sous la convection, mais en même la convection a faibli et s'est quelque peu désorganisé. So, wh'at's happen ? Affaire à suivre ...

[paix 0]

Colin, maintenu a un possiblement généreux 40 noeuds, mais ayant perdu son organisation.

Pour Estelle, le NHC fait le tour du sujet je pense

000

WTPZ42 KNHC 062034

TCDEP2

TROPICAL STORM ESTELLE DISCUSSION NUMBER 4

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072010

200 PM PDT FRI AUG 06 2010

AFTER A RATHER LONG...PERHAPS UNPRECEDENTED...BREAK IN TROPICAL

STORM ACTIVITY IN THE HEART OF THE EASTERN PACIFIC SEASON...

ESTELLE HAS FORMED. SATELLITE IMAGES INDICATE A CDO-TYPE PATTERN

FORMING NEAR THE CENTER ALONG WITH PLENTY OF CONVECTIVE CURVED

BANDS. SATELLITE CLASSIFICATIONS FROM BOTH AGENCIES ARE 35 KT...AND

THIS WILL BE THE INITIAL INTENSITY. FURTHER INTENSIFICATION IS

LIKELY DURING THE NEXT DAY OR SO GIVEN AN ENVIRONMENT OF LIGHT

SHEAR...UPPER-LEVEL DIVERGENCE...AND RATHER WARM WATERS. MODEL

GUIDANCE IS A LITTLE HIGHER THAN BEFORE...BUT NONE OF THEM MAKE

ESTELLE A HURRICANE. THE NHC FORECAST IS NUDGED UPWARD...AND

REMAINS NEAR OR ABOVE THE GUIDANCE.

A SERIES OF MICROWAVE IMAGES HELPED SET THE INITIAL MOTION AT

290/10. THIS GENERAL MOTION IS EXPECTED FOR THE NEXT DAY OR SO DUE

TO RIDGING OVER MEXICO. THERE REMAINS A SPLIT IN THE MODEL

GUIDANCE WITH THE GFDL/HWRF/GFDN MOVING THE SYSTEM TO THE NORTHWEST

IN A COUPLE OF DAYS DUE TO A BREAK IN THE RIDGE. MOST OF THE

GLOBAL MODELS ARE FARTHER SOUTH...SHOWING A SHALLOWER SYSTEM THAT

SLOWS DOWN AS IT GETS CAUGHT UP IN LARGE-SCALE SOUTHWESTERLY FLOW

SOUTH OF MEXICO. SINCE THE SYSTEM IS LIKELY TO WEAKEN IN A COUPLE

OF DAYS BEFORE IT REACHES THE BREAK...A SOUTHERN SOLUTION IS

ANTICIPATED AND THE OFFICIAL TRACK FORECAST IS SHIFTED IN THAT

DIRECTION. THERE IS CONSIDERABLE UNCERTAINTY...HOWEVER...AT THE

LONGER-RANGES OF THIS FORECAST DUE TO THE LARGE MODEL SPREAD.

FORECAST POSITIONS AND MAX WINDS

INITIAL 06/2100Z 17.2N 105.0W 35 KT

12HR VT 07/0600Z 17.7N 106.3W 45 KT

24HR VT 07/1800Z 18.2N 107.8W 55 KT

36HR VT 08/0600Z 18.6N 109.0W 55 KT

48HR VT 08/1800Z 19.0N 110.0W 50 KT

72HR VT 09/1800Z 19.5N 111.5W 40 KT

96HR VT 10/1800Z 19.5N 112.5W 30 KT...POST-TROP/REMNT LOW

120HR VT 11/1800Z 19.5N 113.5W 20 KT...POST-TROP/REMNT LOW

$$

FORECASTER BLAKE

[paix 0]

Pour Estelle, elle aura le mérite de mettre un terme à 40 jours sans cyclone tropical dans le Paicifque Est. Pour le reste, ce sera une tempête ultra short lived sans aucun intérêt.

000

WTPZ42 KNHC 071449

TCDEP2

TROPICAL STORM ESTELLE DISCUSSION NUMBER 7

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL EP072010

800 AM PDT SAT AUG 07 2010

A LARGE BURST OF CONVECTION IS OCCURRING NEAR OR SLIGHTLY WEST OF

THE APPARENT CENTER OF ESTELLE DURING THE PAST FEW HOURS. ALTHOUGH

FIRST VISIBLE IMAGES ARE A LITTLE INCONCLUSIVE... A RECENT 1231 UTC

SSMI PASS WAS QUITE USEFUL IN LOCATING THE LOW-LEVEL CENTER.

CURRENT SATELLITE CLASSIFICATIONS DO NOT SUGGEST ANY CHANGE IN

INTENSITY...SO THE INITIAL WINDS WILL REMAIN 45 KT. THE SYSTEM HAS

ABOUT 24 HOURS TO INTENSIFY BEFORE INCREASING SOUTHEASTERLY

SHEAR...COOLER WATERS...AND A MORE STABLE ATMOSPHERE TAKES ITS TOLL

ON ESTELLE. THE NHC FORECAST IS A LITTLE LOWER THAN THE PREVIOUS

ONE...BUT REMAINS AT THE UPPER END OF THE INTENSITY GUIDANCE

SPECTRUM.

THE INITIAL MOTION IS 280/8. A WEST TO WEST-NORTHWEST MOTION IS

LIKELY FOR THE NEXT FEW DAYS AS WEAK RIDGING REMAINS TO THE NORTH

OF ESTELLE. THE CYCLONE SHOULD SLOW DOWN WHEN THE RIDGE BREAKS DOWN

AND IT ENCOUNTERS INCREASING SOUTHWESTERLY FLOW BY LATE TOMORROW.

THE ALTERNATE SCENARIO OF THE STORM TURNING MORE TO THE NORTHWEST

IS NOT FAVORED AT THIS TIME...WITH ONLY THE NOGAPS AND HWRF SHOWING

THAT MOTION. THE OTHER MODEL GUIDANCE IS IN RELATIVELY GOOD

AGREEMENT ON A MORE WESTWARD TRACK...AND THE NHC FORECAST IS

SHIFTED SOUTH OF THE PREVIOUS ONE. STRONG SOUTHWESTERLY FLOW

SHOULD CAUSE ESTELLE TO SLOW DRAMATICALLY IN THE LONG RANGE...AND

THE CYCLONE COULD EVEN TURN EASTWARD AS SUGGESTED BY SEVERAL GLOBAL

MODELS AS A REMNANT LOW.

FORECAST POSITIONS AND MAX WINDS

INITIAL 07/1500Z 17.1N 107.6W 45 KT

12HR VT 08/0000Z 17.3N 108.7W 50 KT

24HR VT 08/1200Z 17.7N 110.0W 55 KT

36HR VT 09/0000Z 17.9N 111.1W 50 KT

48HR VT 09/1200Z 18.0N 112.2W 45 KT

72HR VT 10/1200Z 18.0N 113.5W 35 KT

96HR VT 11/1200Z 17.8N 114.0W 25 KT...POST-TROP/REMNT LOW

120HR VT 12/1200Z 17.5N 114.5W 20 KT...POST-TROP/REMNT LOW

$$

FORECASTER BLAKE

On note bien devant Estelle, au délà du 100° Ouest, cette zone d'air plus stable et ses SSTs plus fraîches dont parle le NHC.

[ElNino27 0]

L'onde de l'Atlantique Central a 60% de chances d'évoluer en cyclone tropical, mais a priori elle est trop au Nord pour affecter les populations.