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

[paix 0]

Un billet du blog de Jeff Masters :

http://www.wunderground.com/blog/JeffMaste...l?entrynum=1678

Je ne vous sort ici que la partie sur la climatologie et les records à gogo qu'enfile 2010. Pour le reste, il livre à son habitude son intéressante opinion sur Tomas, et son futur.

Tomas, Shary, and the 2010 hurricane season in perspective

Tomas' formation ties 2010 with 1995 and 1887 for 3rd place for most number of named storms in an Atlantic hurricane season. Only 2005 (28 named storms) and 1933 (21 named storms) were busier. Atlantic hurricane records go back to 1851, though there were likely many missed named storms prior to the beginning of satellite coverage in the mid-1960s. The intensification of Shary and Tomas into hurricanes today brings the total number of hurricanes this season to twelve, tying 2010 with 1969 and 1887 for second place for most hurricanes in a season. The record is held by 2005 with fifteen hurricanes, and I don't think we'll beat that record this year!

The formation of Tomas so far south and east this late in the season is unprecedented in the historical record; no named storm has ever been present east of the Lesser Antilles (61.5°W) and south of 12°N latitude so late in the year. Hurricane Six of 1896 came close--it was also a tropical storm south of 12°N and east of 61.5°W on October 29, but nine hours earlier in the day. That storm recurved to the north and missed the Lesser Antilles. Tomas' track through the southern Lesser Antilles so late in the year is unprecedented. There have been only two other tropical storms that formed after October 15 south of 12°N and east of 61.5°W: Hurricane Jose, which was a tropical storm in that region on October 18, 1999, and Tropical Storm Nicolas, on October 16, 2003. Tomas most reminds me of a storm I flew into with the Hurricane Hunters--Hurricane Joan of 1988, which was a tropical storm on October 14 near Tomas' current location, and later strengthened into a Category 4 hurricane that hit Nicaragua. According to Chenoweth (2008), Tomas is the first tropical storm to cross through the Lesser Antilles Islands south of 16°N this late in the year since 1724. In that year, a tropical storm on 12 November crossed the islands at 13.7°N 61.5°W, and later became a hurricane that affected Jamaica. There was also a hurricane on 30 October 1671 that crossed 61.5°W at 13.3°N, and did damage on Barbados.

Another unusual aspect of Tomas' formation is that we now have two simultaneous hurricanes in the Atlantic Ocean on October 30. There has been only one hurricane season since 1851 that had had two simultaneous hurricanes later in the year--1932, when Hurricane Ten and Hurricane Eleven both existed November 7 - 10. Today is also the 5th latest date in the season that there have been two simultaneous named storms in the Atlantic. The record was set way back in 1887, when Hurricane Eighteen and Tropical Storm Nineteen were both active on December 8. There were three years that had simultaneous November named storms: 1932, 1961, and 2001.

Pour ce mémorable Automne 2010 de l'Atlantique tropical

Modifié 30 octobre 2010 par paix

[paix 0]

Mauvais, mauvais, l'œil se contracte encore un peu plus, le mur s'enroule et se renforce encore un peu plus. La probabilité de voir Tomas nous faire une grosse intensification rapide ce soir/cette nuit se renforce. Les images satellites de 1645UTC ne sont pas encore accessibles, mais ne seront sans doute qu'une confirmation de la signature radar. Une dropsonde a trouvé 992 hPa dans 14 nœuds de vent à 1644 UTC (l'heure de l'image radar), ce qui ferait quelque chose comme 991 hPa au centre de Tomas. La pression a donc repris sa baisse et confirme le renforcement actuel de Tomas. Pendant ce temps, l'avion est toujours empêtré dans des problèmes de communications. Heureusement que ce n'est pas plus grave, et puis on a quand même le message de la dropsonde, bien utile malgré tout.

Modifié 30 octobre 2010 par paix

[paix 0]

On a quand même le message Vortex :

Product: Air Force Vortex Message (URNT12 KNHC)

Transmitted: 30th day of the month at 16:56Z

Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 300)

Storm Number & Year: 21L in 2010

Storm Name: Tomas (flight in the North Atlantic basin)

Mission Number: 2

Observation Number: 26

A. Time of Center Fix: 30th day of the month at 16:29:50Z

B. Center Fix Coordinates: 13°09'N 60°46'W (13.15N 60.7667W)

B. Center Fix Location: 34 miles (54 km) to the E (96°) from Kingstown, Saint Vincent and the Grenadines.

C. Minimum Height at Standard Level: 3,025m (9,925ft) at 700mb

D. Estimated (by SFMR or visually) Maximum Surface Wind: 54kts (~ 62.1mph)

E. Location of the Estimated Maximum Surface Wind: 33 nautical miles (38 statute miles) to the WNW (299°) of center fix

F. Maximum Flight Level Wind Inbound: From 360° at 58kts (From the N at ~ 66.7mph)

G. Location of Maximum Flight Level Wind Inbound: 42 nautical miles (48 statute miles) to the WNW (295°) of center fix

H. Minimum Sea Level Pressure: 992mb (29.29 inHg)

I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 9°C (48°F) at a pressure alt. of 3,051m (10,010ft)

J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 13°C (55°F) at a pressure alt. of 3,043m (9,984ft)

K. Dewpoint Temp (collected at same location as temp inside eye): 2°C (36°F)

K. Sea Surface Temp (collected at same location as temp inside eye): Not Available

L. Eye Character (Undecoded): RAGGED BANDING

M. Eye Shape & Diameter: Circular with a diameter of 40 nautical miles (46 statute miles)

N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature

N. Fix Level: 700mb

O. Navigation Fix Accuracy: 0.02 nautical miles

O. Meteorological Accuracy: 1 nautical mile

Remarks Section - Remarks That Were Decoded...

Maximum Flight Level Wind: 67kts (~ 77.1mph) in the north quadrant at 14:16:50Z

Remarks Section - Additional Remarks...

RADAR STRONG BAND SOUTH SEMI-CIRCLE RAGGED APPEARANCE OVERALL

LAST REPORT

RADAR STRONG BAND SOUTH SEMI-CIRCLE RAGGED APPEARANCE OVERALL

Le mur Sud reste mal défini. À voir quels effets cela pourra avoir, mais il semblerait que le mur ne soit pas aussi solide que ne le laisserait penser le radar. Tomas n'est peut être toujours pas décidé à s'organiser décemment.

[ElNino27 0]

Ah ben fallait bien ça pour bien entretenir l'épidémie de choléra ... faudrait déménager le pays à ce rythme-là. Qui a eu l'idée de peupler cette île, franchement ?

[paix 0]

Au moins, si Tomas leur passe dessus , il n'y aura plus de question à savoir comment déménager le pays ....

(ceci n'est que de l'humour noir )

Pour Tomas, la der' image visible vient d'ailleurs montrer que le mur Sud est "ragged"

On pourra aussi noter un front de rafale à l'avant de Tomas, qui a été produit lors de l'effondrement du mur Ouest ce midi, lors de l'invasion par enroulement du mur Est que j'avais précédemment souligné. On s'en fout un peu au final d'où il sort, mais un front de rafale peut aider à stabiliser la couche limite à l'avant d'un ouragan, et pourrait aussi poser difficulté à Tomas qui semble quand même pas mal galéré déjà.

[paix 0]

Curieux, parce que le radar est vraiment rassurant sur la capacité de Tomas à se creuser :

On va attendre un peu d'avoir une plus longue séquence d'images satellites pour voir si le radar a raison ou pas.

[paix 0]

Le radar a peut être raison finalement. Pas mal de pileus au sommet des cumulonimbus sur le mur Est. L'œil en visible va sans doute se faire bouffer, mais la structure de Tomas semble maintenant suffisamment solide pour qu'il garde l'œil sous ce magma convectif. Si cela se passe ainsi, il réémergera quand Tomas se sera suffisamment renforcé.

Modifié 30 octobre 2010 par paix

[paix 0]

Tomas est pratiquement stationnaire depuis quelques heures, et en plus l'œil passe juste entre Sainte Lucie et Saint Vincent. Les pluies sont torrentielles sur ces deux îles, qui sont, respectivement, sous le mur Nord et Sud de Tomas.

Pour Tomas, il faut espérer maintenant qu'il s'est structuré que l'intense convection de la bande Est qui affecte actuellement La Barbade ne va pas lui jour un mauvais tour.

Modifié 30 octobre 2010 par paix

[paix 0]

Une des dernières images visible de Tomas. L'œil n'est plus visible, mais est toujours bien là.

[paix 0]

Ouah, c'est de l'efficacité lapidaire ça

Bulletin sorti avec au moins 1/2h d'avance, et aussi presque aussi laconique que Cambronne...

000

WTNT45 KNHC 302034

TCDAT5

TROPICAL STORM SHARY DISCUSSION NUMBER 8

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL202010

500 PM AST SAT OCT 30 2010

SATELLITE IMAGES INDICATE THAT A STRONG COLD FRONT IS NOW

INTERACTING WITH SHARY AND THE FSU CYCLONE PHASE SPACE DIAGRAMS

SUGGEST THAT CYCLONE HAS TRANSITIONED TO A POST-TROPICAL CYCLONE.

BASED ON THESE DATA...SHARY IS NO LONGER CONSIDERED A TROPICAL

CYCLONE AND THIS WILL BE THE LAST ADVISORY ISSUED ON THIS STORM

FROM THE NATIONAL HURRICANE CENTER.

THE POST-TROPICAL STORM IS RACING NORTHEASTWARD AT ABOUT 42 KT.

THIS MOTION IS EXPECTED TO CONTINUE UNTIL THE CYCLONE BECOMES

ABSORBED BY THE FRONT WITHIN THE NEXT 6 TO 12 HOURS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 30/2100Z 39.2N 50.9W 60 KT

12HR VT 31/0600Z 42.8N 44.2W 55 KT...DISSIPATED

24HR VT 31/1800Z...DISSIPATED

$$

FORECASTER CANGIALOSI

Quand on voit les images satellites, on peut les comprendre quand même

Il n'y a plus grand chose à dire. Le front est évident, et Sharry est perdu dans ce front.

[paix 0]

Maintenu à 65 nœuds, mais le NHC mentionne que cela peut être un peu bas comme estimation, et évoque également lesz dégâts subis à Sainte Lucie et Saint Vincent. Stewart est toujours aussi loquace, et apporte un tas de petits détails intéressant dans cette discussion.

000

WTNT41 KNHC 302046

TCDAT1

HURRICANE TOMAS DISCUSSION NUMBER 6

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL212010

500 PM AST SAT OCT 30 2010

AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING TOMAS

THIS AFTERNOON FOUND MAXIMUM 700 MB FLIGHT-LEVEL WINDS OF 67 KT IN

THE NORTH QUADRANT...WHICH EQUATES TO ABOUT 60 KT SURFACE WINDS.

SATELLITE INTENSITY ESTIMATES ARE A CONSENSUS T4.0/65 KT FROM TAFB

AND SAB. THE STRUCTURE OF TOMAS HAS IMPROVED CONSIDERABLY IN RADAR

IMAGERY FROM MARTINIQUE...AND THE CYCLONE NOW POSSESSES A CLOSED 25

N MI DIAMETER EYE. THE INTENSITY IS BEING HELD AT 65 KT FOR THIS

ADVISORY...WHICH COULD BE A LITTLE LOW BASED ON SOME OF THE DAMAGE

REPORTS THAT HAVE BEEN RECEIVED FROM HAM RADIO OPERATORS ON ST.

LUCIA AND ST. VINCENT.

THE INITIAL MOTION ESTIMATE IS 290/09. TOMAS REMAINS ON TRACK...

AND THERE IS NO SIGNIFICANT CHANGE TO THE PREVIOUS FORECAST TRACK OR

REASONING. THE LOW- TO MID-LEVEL RIDGE TO THE NORTH OF TOMAS IS

EXPECTED TO CONTINUE TO BUILD WESTWARD ACROSS THE GREATER ANTILLES

FOR THE NEXT 96 HOURS...WHICH SHOULD KEEP TOMAS ON A WEST-NORTHWEST

TO WESTWARD TRACK. HOWEVER...A BROAD LONGWAVE TROUGH CURRENTLY

ALONG THE U.S. WEST COAST IS EXPECTED TO MOVE EASTWARD AND THEN

SOUTHEASTWARD INTO THE SOUTHEASTERN UNITED STATES...AND PINCH OFF A

CLOSED LOW OVER THE GULF OF MEXICO AND SOUTHEASTERN MEXICO BY 120

HOURS. THE STRONG SOUTHWESTERLY FLOW ON THE EAST SIDE OF THE

AFOREMENTIONED TROUGH AND LOW IS EXPECTED TO RESULT IN A

SIGNIFICANT EROSION OF THE WESTERN PORTION OF THE GREATER ANTILLES

RIDGE AND CAUSE THE STEERING CURRENTS ACROSS THE WESTERN AND

CENTRAL CARIBBEAN SEA TO WEAKEN...ALLOWING TOMAS TO SLOW DOWN

CONSIDERABLY AND BEGIN TO MOVE POLEWARD. MOST OF THE MODEL GUIDANCE

IS IN GOOD AGREEMENT ON THIS GENERAL TRACK SCENARIO EXCEPT FOR

SPEED DIFFERENCES. THE OFFICIAL FORECAST TRACK IS JUST AN UPDATE OF

THE PREVIOUS ADVISORY TRACK...AND REMAINS ALONG THE SOUTHERN EDGE

OF THE NHC GUIDANCE ENVELOPE...BUT NOT AS FAR SOUTH AS THE GFS AND

ECMWF MODELS.

WITH A CLOSED EYE AND A FAVORABLE UPPER-LEVEL ENVIRONMENT...TOMAS IS

FORECAST TO STRENGTHEN FOR THE NEXT 24 HOURS OR SO BEFORE WEAK

WESTERLY 400-300 MB WINDS UNDERCUT THE IMPRESSIVE OUTFLOW LAYER AND

ENTRAINMENT OF DRY MID-LEVEL AIR FROM THE WEST COMBINE TO INTERRUPT

THE STRENGTHENING PROCESS. HOWEVER...BY 48-72 HOURS...ENVIRONMENTAL

CONDITIONS ARE FORECAST TO IMPROVE...WHICH SHOULD ALLOW TOMAS TO

RESUME STEADY INTENSIFICATION. THE GFS-BASED SHIPS AND LGEM MODELS

ARE FORECASTING STEADY WEAKENING AFTER 48 HOURS...BUT THAT IS

BELIEVED TO BE DUE TO ERRONEOUS MODEL-INDUCED SOUTHWESTERLY

VERTICAL SHEAR AFFECTING TOMAS AS A RESULT OF THE OFFICIAL FORECAST

TRACK BEING ABOUT 120 N MI NORTH OF THE LARGE SCALE UPPER-LEVEL

ANTICYCLONE DEPICTED IN THE GFS MODEL. THE INTENSITY FORECAST

REMAINS ABOVE THE SHIPS/LGEM MODELS...AND IS SIMILAR TO THE

PREVIOUS FORECAST AND LAST TWO GFDL MODEL RUNS.

FORECAST POSITIONS AND MAX WINDS

INITIAL 30/2100Z 13.5N 61.4W 65 KT

12HR VT 31/0600Z 14.0N 63.4W 75 KT

24HR VT 31/1800Z 14.5N 65.7W 80 KT

36HR VT 01/0600Z 14.9N 67.9W 80 KT

48HR VT 01/1800Z 15.2N 69.7W 85 KT

72HR VT 02/1800Z 15.7N 72.4W 90 KT

96HR VT 03/1800Z 16.0N 74.0W 95 KT

120HR VT 04/1800Z 16.5N 74.5W 100 KT

$$

FORECASTER STEWART

[ElNino27 0]

Ben m**** alors !

En tout cas, après un départ en fanfare, Tomas semble être un peu moins bombe.

Autre chose : il devrait nous faire dépasser les 150 d'ACE, donnant ainsi à l'année 2010 le qualificatif de "hyperactive" ...

[ElNino27 0]

From the NHC

..OBSERVATIONS FROM ST. LUCIA INDICATE THAT TOMAS HAS STRENGTHENED...

:00 PM AST Sat Oct 30

Location: 13.5°N 61.6°W

Max sustained: 90 mph

Moving: WNW at 10 mph

Min pressure: 982 mb

[paix 0]

Malheureusement

Sainte Lucie a donc sans doute connu des vents de forces ouragan un certain temps, avec de fortes précipitations.

000

WTNT41 KNHC 302202

TCDAT1

HURRICANE TOMAS SPECIAL DISCUSSION NUMBER 7

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL212010

600 PM AST SAT OCT 30 2010

REPORTS FROM THE METEOROLOGICAL SERVICE OF ST. LUCIA INDICATE THAT

TOMAS HAS STRENGTHENED...WITH MAXIMUM WINDS OF 80 KT. THIS SPECIAL

ADVISORY IS ISSUED TO INCREASE THE INITIAL AND FORECAST INTENSITY

OF THE HURRICANE. NO OTHER CHANGES TO THE FORECAST HAVE BEEN MADE.

FORECAST POSITIONS AND MAX WINDS

INITIAL 30/2200Z 13.5N 61.6W 80 KT

12HR VT 31/0600Z 14.0N 63.4W 85 KT

24HR VT 31/1800Z 14.5N 65.7W 90 KT

36HR VT 01/0600Z 14.9N 67.9W 90 KT

48HR VT 01/1800Z 15.2N 69.7W 95 KT

72HR VT 02/1800Z 15.7N 72.4W 95 KT

96HR VT 03/1800Z 16.0N 74.0W 95 KT

120HR VT 04/1800Z 16.5N 74.5W 100 KT

$$

FORECASTER BERG/FRANKLIN

Tomas est en train d'exploser...

L'œil est déjà en train de réapparaître au milieu d'un mur très froid.

Les infos indiquent que Sainte Lucie et Saint Vincent ont été sévèrement touchés...

http://www.stormcarib.com/reports/current/

- tomas is beating us badly

By colvinharry at yahoo.co.uk

Date: Sat, 30 Oct 2010 21:26:48 +0000

As I write this I have low battery but just to let our stormcarib friends know

that we have received a hard hit from tomas many roofs gone destruction

evrywhere and tomas has slowed down.keep praying for st vincent and our friends

in st lucia.take care all

Sent from my BlackBerry® device from Digicel

En gros, il est sur portable, batterie faible, destruction partout, toits envolés.

- Darkness falls as tomas continues to pumel us

By Haniff Sutherland <hanniff at gmail.com>

Date: Sat, 30 Oct 2010 18:09:51 -0400

It is with a heavy heart I report on conditions in st vincent, many

homes have lost their roofs, my sister in Georgetown on the north

eastern side lost her roof, this was a well built house; I did not

expect this, across the island, report are coming in of downed

telephone lines, power is off. About 50 houses have lost their roofs.

unconfirmed reports are that a stone fell on a house in otley hall

with 3 persons in it. and a house missing in green hill. and the cargo

ship sting ray is about to run ashore in salt pond.

A yacht may also be experiencing trouble off cane garden point. St

Vincent will take a long time to recover from this one.

Toits envolés, ligne de téléphone à terre, électricité coupé. Il y aurait aussi des morts.

- Storm update

By "Louis Todor" <ltodor at candw.lc>

Date: Sat, 30 Oct 2010 13:43:15 -0400

30 oct 2010 13:30

Situation pretty stormy down here in Choiseul. Power is down since around 10 am. I drove all the way to Vieux Fort to see what's happening.

Trees are blocking the main road at some places as much as 2/3 way but it is still possible to pass. Lot of rubbish on the road everywhere, branches, pieces of signs etc.

The main road is blocked completely at True Value, just before reaching Vieux Fort where 2 posts with power line are now across the main road together with a part of a roof. It looks like no power for a while.

I'm running on a generator, and will try to send updates providing I still have internet access.

God Bless you all.

Louis Todor

Électricité coupée, routes, débris, branches, etc... sur la route. Deux postes (transfos ?) avec les lignes sont à terre à Vieux Fort.

Et cela ne fait que commencer.

Modifié 30 octobre 2010 par paix

[paix 0]

L'image micro onde confirme que le mur est solide, complet à ~70/80%. Il reste une faiblesse au sud, visible sur l'image IR également, au niveau de Saint Vincent.

Le radar semble indiqué aussi que l'œil poursuit sa contraction :

Tomas semble en route vers le statut d'ouragan majeur. Le seul point qui me pose problème est l'énorme bande convective à l'Est qui pourrait ralentir le développement de Tomas, et qui promet un Dimanche agité pour les Antilles.

Modifié 30 octobre 2010 par paix

[paix 0]

Tomas, premier catégorie 5 depuis Félix ?

[paix 0]

Tomas s'est pour la énième fois réorganisé. La bande convective Est a fait les frais de cette réorganisation, et finalement Tomas s'est reconstitué autour de son œil. Le mur s'est réchauffé, mais reste assez froid. Affaire à suivre...

[ElNino27 0]

Cat5 ? Là, vous rêvez ...

[ElNino27 0]

L'ACE de 2010 est à 153 ... 2010 est officiellement "hyperactive" ...

[paix 0]

Cat5 ? Là, vous rêvez ...

Pourquoi, on a plus le droit ?

Tomas souffre actuellement du cisaillement de vent, et a faibli en ouragan de catégorie 1. Il a donc échoué à devenir un majeur avant la fin de la journée. Après avoir passé deux jours à essayer de s'organiser proprement, le voilà qui rencontre des conditions plus défavorables.

P.S. : Je précise que cela ne se lit sans doute pas dans ce sens là, mais quand je parlais de Tomas en cat5, c'était juste une boutade... Pour le coup, je n'étais vraiment pas sérieux et étais juste impressionné par sa convection profonde.

Modifié 31 octobre 2010 par paix

[paix 0]

L'avion a même trouvé "seulement" 990 hPa

Tomas était dans un environnement trop favorable, et maintenant il se fait mettre en pièce par le cisaillement et l'injection d'air sec dans un environnement nettement moins favorable. Dur, dur la vie d'ouragan quand même.

Modifié 31 octobre 2010 par paix

[paix 0]

C'est encore pire que ce que l'image satellite satellite avoue. Tomas est vraiment mal en point. Il n'y a plus d'alignement vertical, la dropsonde a trouvé 39 nœuds et 994 hPa à la surface et 4 nœuds à 700 hPa et 3055 mètres. En surface, on est pratiquement dans ce qui reste du mur, en altitude on est au centre.

Edit : Le Vortex vient d'arriver :

Product: Air Force Vortex Message (URNT12 KNHC)

Transmitted: 31st day of the month at 17:58Z

Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 309)

Storm Number & Year: 21L in 2010

Storm Name: Tomas (flight in the North Atlantic basin)

Mission Number: 4

Observation Number: 05

A. Time of Center Fix: 31st day of the month at 17:29:30Z

B. Center Fix Coordinates: 14°13'N 64°15'W (14.2167N 64.25W)

B. Center Fix Location: 314 miles (505 km) to the SSE (158°) from San Juan, Puerto Rico (USA).

C. Minimum Height at Standard Level: 3,059m (10,036ft) at 700mb

D. Estimated (by SFMR or visually) Maximum Surface Wind: 64kts (~ 73.6mph)

E. Location of the Estimated Maximum Surface Wind: 7 nautical miles (8 statute miles) to the WNW (291°) of center fix

F. Maximum Flight Level Wind Inbound: From 47° at 48kts (From the NE at ~ 55.2mph)

G. Location of Maximum Flight Level Wind Inbound: 20 nautical miles (23 statute miles) to the NW (323°) of center fix

H. Minimum Sea Level Pressure: 994mb (29.35 inHg)

I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 10°C (50°F) at a pressure alt. of 3,050m (10,007ft)

J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 16°C (61°F) at a pressure alt. of 3,043m (9,984ft)

K. Dewpoint Temp (collected at same location as temp inside eye): 9°C (48°F)

K. Sea Surface Temp (collected at same location as temp inside eye): Not Available

L. Eye Character: Open from the southeast to the southwest

M. Eye Shape & Diameter: Circular with a diameter of 30 nautical miles (35 statute miles)

N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature

N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 700mb

O. Navigation Fix Accuracy: 0.02 nautical miles

O. Meteorological Accuracy: 1 nautical mile

Remarks Section - Remarks That Were Decoded...

Maximum Flight Level Wind: 48kts (~ 55.2mph) in the northwest quadrant at 17:22:50Z

Remarks Section - Additional Remarks...

SFC CNTR BEARING 280 AT 04 NM FROM FL CNTR

SFC CNTR BEARING 280 AT 04 NM FROM FL CNTR

Centre de surface à 280° et 4 miles nautique (dans les 7 kilomètres) du centre d'altitude (inclinaison de 21° environ). Violent....

280°, c'est pratiquement du plein Ouest (270° le plein Ouest), ce qui est en cohérence avec le cisaillement d'Ouest (ou, pour être correct, avec les vents d'altitude d'Ouest forts qui cisaillent le système).

Modifié 31 octobre 2010 par paix

[paix 0]

Really looking bad. Tomas his producing numerous outflow boundaries, visible in the west side of the storm. I also think that we can see stratocumulus clouds beneath the outflow of the west side. If this is the case, stratocumulus is a sign of the extremely dry and stable air which is driven at mid level in the west side core of Tomas.

Edit :

995mb (29.38 inHg) Sea Level (Surface) 27.4°C (81.3°F) 25.4°C (77.7°F) 45° (from the NE) 13 knots (15 mph)

1000mb -42m (-138 ft) Other data not available.

925mb 650m (2,133 ft) 24.2°C (75.6°F) 22.8°C (73.0°F) 90° (from the E) 11 knots (13 mph)

850mb 1,395m (4,577 ft) 24.2°C (75.6°F) Approximately 16°C (61°F) 90° (from the E) 7 knots (8 mph)

Apparently not as worst as the last dropsonde, but still bad.

Modifié 31 octobre 2010 par paix

[paix 0]

Worst, or better ? So good, so bad

The eyewall has dissipated, but Tomas is a little more vertically aligned.

Product: Air Force Vortex Message (URNT12 KNHC)

Transmitted: 31st day of the month at 19:21Z

Aircraft: Air Force Aircraft (Last 3 digits of the tail number are 309)

Storm Number & Year: 21L in 2010

Storm Name: Tomas (flight in the North Atlantic basin)

Mission Number: 4

Observation Number: 08

A. Time of Center Fix: 31st day of the month at 18:58:30Z

B. Center Fix Coordinates: 14°18'N 64°34'W (14.3N 64.5667W)

B. Center Fix Location: 301 miles (485 km) to the SSE (161°) from San Juan, Puerto Rico (USA).

C. Minimum Height at Standard Level: 1,391m (4,564ft) at 850mb

D. Estimated (by SFMR or visually) Maximum Surface Wind: 61kts (~ 70.2mph)

E. Location of the Estimated Maximum Surface Wind: 31 nautical miles (36 statute miles) to the ENE (72°) of center fix

F. Maximum Flight Level Wind Inbound: From 101° at 65kts (From between the E and ESE at ~ 74.8mph)

G. Location of Maximum Flight Level Wind Inbound: 54 nautical miles (62 statute miles) to the NE (55°) of center fix

H. Minimum Sea Level Pressure: 995mb (29.38 inHg)

I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 16°C (61°F) at a pressure alt. of 1,528m (5,013ft)

J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 25°C (77°F) at a pressure alt. of 1,513m (4,964ft)

K. Dewpoint Temp (collected at same location as temp inside eye): 18°C (64°F)

K. Sea Surface Temp (collected at same location as temp inside eye): Not Available

L. Eye Character: Not Available

M. Eye Shape: Not Available

N. Fix Determined By: Penetration, Radar, Wind, Pressure and Temperature

N. Fix Levels (sfc and flt lvl centers are within 5nm of each other): Surface and 850mb

O. Navigation Fix Accuracy: 0.02 nautical miles

O. Meteorological Accuracy: 1 nautical mile

Remarks Section - Remarks That Were Decoded...

Maximum Flight Level Wind: 65kts (~ 74.8mph) in the northeast quadrant at 18:39:20Z

Remarks Section - Additional Remarks...

SFC CNTR BEARING 180 AT APPROX 2 NM FROM FL CNTR

EYEWALL DISSIPATED.

Modifié 31 octobre 2010 par paix

[paix 0]

Here, "Inland" means Haïti, and 90 knots is a category 2 hurricane, only 6 knots under the magical line between hurricane and major hurricane status...

But, major hurricane or not, Tomas is a major threat for Haïti.

The weakening trend was accurately forecasted by the NHC, but not his great magnitude. And so, Tomas will take a longer time to recover, preventing probably Tomas to become the fifth category 4 of this season.

000

WTNT41 KNHC 312031

TCDAT1

HURRICANE TOMAS DISCUSSION NUMBER 11

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL212010

500 PM AST SUN OCT 31 2010

DATA FROM AN AIR FORCE RESERVE RECONNAISSANCE AIRCRAFT INDICATE THAT

TOMAS HAS WEAKENED A LITTLE MORE. THE AIRCRAFT REPORTED A MAXIMUM

850 MB FLIGHT-LEVEL WIND OF 74 KT...AN SFMR SURFACE WIND OF 64

KT...AND A MINIMUM PRESSURE OF 994 MB. THESE DATA SUPPORT

MAINTAINING TOMAS AS A HURRICANE WITH AN INITIAL WIND SPEED OF 65

KT.

THE INITIAL MOTION IS SLIGHTLY TO THE LEFT AND A LITTLE FASTER THAN

BEFORE...280/10. TOMAS IS FORECAST TO CONTINUE MOVING WESTWARD FOR

THE NEXT COUPLE OF DAYS AS IT REMAINS SOUTH OF A MID-LEVEL RIDGE.

BEYOND THAT TIME...THE CYCLONE IS EXPECTED TO SLOW DOWN AND

GRADUALLY TURN TOWARD THE NORTH AS THE STEERING CURRENTS WEAKEN DUE

TO A LARGE MID- TO UPPER-LEVEL TROUGH MOVING ACROSS THE GULF OF

MEXICO. ALTHOUGH THE TRACK MODEL GUIDANCE IS IN FAIR AGREEMENT IN

THE EVOLUTION OF THE LARGE-SCALE PATTERN...THERE ARE CONSIDERABLE

DIFFERENCES AS TO WHERE AND WHEN THE NORTHWARD TURN OCCURS. THE

OFFICIAL FORECAST IS SIMILAR TO THE PREVIOUS ONE FOR THE NEXT 3 TO

4 DAYS...AND THEN LIES A LITTLE TO THE RIGHT OF THE LAST TRACK TO

COME INTO BETTER AGREEMENT WITH THE LATEST GUIDANCE. THIS TRACK

FORECAST IS CLOSE TO A CONSENSUS OF THE GFS...GFDL...ECMWF...AND

UKMET MODELS. IT SHOULD BE NOTED THAT CONFIDENCE IN THE LONG-TERM

FORECAST POINTS ARE OF LOWER CONFIDENCE THAN NORMAL.

SOME ADDITIONAL WEAKENING SEEMS LIKELY DURING THE NEXT DAY OR TWO AS

SOUTHWESTERLY SHEAR OF 20-25 KT AND SOME MID-LEVEL DRY AIR CONTINUE

TO IMPACT THE CYCLONE. THE OFFICIAL FORECAST FOLLOWS THE TREND IN

THE GUIDANCE AND IS ONCE AGAIN ADJUSTED DOWNWARD...BRINGING TOMAS

BELOW HURRICANE STRENGTH WITHIN THE NEXT 12 HOURS. BEYOND A COUPLE

OF DAYS...THE SHEAR IS EXPECTED TO LESSEN WHILE TOMAS REMAINS OVER

FAVORABLE OCEANIC CONDITIONS. ALL OF THE INTENSITY MODELS RESPOND

AND SHOW THE SYSTEM INTENSIFYING IN THE 3 TO 5 DAY RANGE...AND THE

OFFICIAL FORECAST FOLLOWS SUIT AND IS AT THE HIGH END OF THE

GUIDANCE THROUGHOUT THE FORECAST PERIOD.

FORECAST POSITIONS AND MAX WINDS

INITIAL 31/2100Z 14.4N 64.9W 65 KT

12HR VT 01/0600Z 14.7N 66.4W 60 KT

24HR VT 01/1800Z 15.0N 68.3W 55 KT

36HR VT 02/0600Z 15.0N 69.9W 55 KT

48HR VT 02/1800Z 15.0N 71.3W 60 KT

72HR VT 03/1800Z 15.3N 72.5W 65 KT

96HR VT 04/1800Z 16.0N 73.0W 80 KT

120HR VT 05/1800Z 18.5N 72.5W 90 KT...INLAND

$$

FORECASTER CANGIALOSI/BROWN