ATL : EX TOMAS - Discussion

[latitude_20]

[KWT]

I would be so sure at all snowcane, alot of models restrengthen this system in a few days time as it starts to get picked up by the upper trough and this would make alot of sense to me, systems quite often that far south strengthen, esp if they head NNE.

Besides its probably not as weak as some think right now, I doubt its at 85kts but its certainly still a decent cat-1 IMO.

[cycloneye]

For anyone who may not know yet,with the 5 AM advisory of Tomas at 85kts,the Atlantic reached hyperactive status with 153.0125 ace units.See ACE thread at Talking Tropics forum.

[Gustywind]

Here is the translation of the latest weather forecast for Martinica 5AM given Meteo-France Martinica at le Lamentin.
http://www.meteo.fr/temps/domtom/antill ... ivi_ma.pdf

BULLETIN OF CYCLONIC ATTENTIVENESS FOR MARTINIQUE

Bulletin of follow-up N°1.7 from October 31st, 2010 till local 5:00 am

COLOR: YELLOW DANGER: CYCLONE

Current situation Phenomenon (type, name): hurricane of category 2, TOMAS

Position Distances
At 5 local time, Lat: 14.0 the North Lon: 62.9 West or 210 km on the westsouthwest of the coast of Martinica
Intensity: maximal, average Wind: 160 kph ( 85 knots or 160 Km/h) gusts: 190 kph (105 knots or 190 Km/h)
Radius :
- Wind of strength hurricane (sup at 120 Km/h) up to 65 km of the center.
- Wind of strength storm (sup at 60 Km/h) up to 280 km of the center.
Minimal pressure: 983 hPa. The system is expected to intensified gradually then moving slowly westnorthwest.

Movement : 290 ° Westnorthwest. Speed: 13 Km/h or 7 knots.

Forecasts
Although the weather conditions remain perturbed, this morning, the improvement confirms in the course of hours.
The East wind in East-south-east is decreasing, it blows generally between 30 and 40 Km/h on average with gusts which reach approximately 50/60 Km/h.

The sea remains dangerous, today with average hollows included between 2m50 and 3m50 in the Atlantic Ocean and in the channel of Saint Lucia. Hollows average reaches 1m20 and 1m40 on the Caribbean coast, locally more on the Caribbean South.

Rains are always continuous and can give new accumulations, this morning, of the average from 30 to 40 mm. However, from the middle-day these precipitation ease and should be almost ended at the end of the day.

Measurements coded:

Observed Max Winds:
Vauclin: Est wind at 79 Km/h, gust at 102 Km/h.
Caravelle: Est wind, gust at 68 Km/h.
Fond-Saint-Denis: East-south-east wind, gust at 108 Km/h.
Lamentin: East-north-east wind at 57 Km/h, gust at 88 Km/h.

Precipitations:
In 24 hours, numerous accumulations reached values between 100 and 170 millimeters.

Houlographe:
Bay of Fort-de-France: 1m10, max 1m80.

Comments/ Consequences
The sea remains dangerous on the Atlantic facade and in the channel of Saint Lucia.
The conditions in the coast are also dangerous on Caribbean side. The caution is also recommended in the passage of fords and in flood-risk areas because streams are very reagent.

Summarized
Risk: certain Impact: moderated at locally important.

Validity Duration of the phenomenom
Until Sunday in the middle of the day.

Next bulletin: October 31st at 12 am.

[Gustywind]

Concerning the locality of the Vauclin in Martinica, it should be noted that this area is on the southerneastern tip of the island of Martinica, so it's understanstable at the TS winds were really reported.

[SouthDadeFish]

Judging by the recent satellite trend, the 06Z GFDL forecast looks very reasonable. It looks like shear and dry air have messed with him. It remains to be seen if he can mix out the dry air, and if he can't, weakening to a moderate TS like the GFDL says, looks very possible right now. In fact, I really hope this weakening does commence so that he is not a burden to anywhere else.

[Gustywind]

News from our friends of Dominica
- Toxic Tomas...
By Conan Shillingford <nichs at hotmail.com>
Date: Sun, 31 Oct 2010 11:45:57 +0000

Good morning all,

So far Unfortunately, the effects of Hurricane Tomas appear to be nothing short of Horrendous...from St. Vincent in the South to as far north as Guadeloupe the impact has been moderate to severe depending on where one is posting from…

Here in the Nature Isle, Dominica we have not been left unscathed -thus far the winds have been gusting to about 25-35 Knots -sometimes as high as 40 knots or greater on the North East coast accompanied by driving rains. So far no thunder has been heard at all. The occasional higher gusts often create a howling sound- which only makes me even more apprehensive to think of what terrible Tomas has done to the islands of St. Lucia and St. Vincent in addition to what Barbados has already experienced. Major lessons ought to be learnt from the ‘surprise’ nature of this system’s development and the resultant deficiency in forecasting and warning by regional authorities et al.

Amazingly it is said that the Creole Festival went off last night...Incredible but that there were reports of some structural damage around town -though apparently minimal. Here the vegetation has taken most of the beating with leaves, branched and twigs down etc. Some banana plants have also taken a good lashing from Tomas.



For most of yesterday and this morning there have been some brief but moderate squall lines coming through. The Atlantic has been churning madly and I’m pretty sure the storm swells/ surges have reached the Caribbean Sea- western facing side of the island by now. I do hope that Yesterday's inclemency from early in the morning which continues into this morning gave most people enough time to be ready for what we had to endure overnight-early this morning. It appears from the satellite that as the system moves to the wnw now at an even slower pace that we will have to deal with a few more heavy squall lines into the next day. I do pray that everyone will remain safe throughout the day especially those who may still be out in this weather at the various Creole/ Independence events.

Major tropical systems are never a pleasant experience! God’s Blessings to all.

[Gustywind]

[Gustywind]

[KWT]

The only thing I will say is the Vis imagery, esp close up actually shows its not as unhealthy as the numerous IR channels suggests, and the microwave imagery suggests the inner core isn't totally gone yet either...still the idea of steady weakening looks good for at least the very short term. I'd go with 75kts right now.

[wxman57]

Here's a visual to help those of you in south Florida better understand why I don't think you need to be concerned about Tomas. This is the GFS prediction for upper-level winds for the 5 day track point, Thursday morning about this time. And it's not just the GFS, it's all models showing the very deep winter-like trof/upper low along the east U.S. Coast.

The graphic only shows wind contours of 50 kts (60 mph) or greater. Note that the southwesterly winds across Florida are 80-110 kts. Looking ahead another day or two, the trof digs more to the southeast and winds remain in that range across Florida, but the 50kt contour approaches Jamaica. That's why we expect the sharp right turn south of Haiti/DR.

[Gustywind]

Looking at my window, the SUN is trying to make a very shy comeback between the clouds but really appreciated. Whereas, given the sat pic good patchs of strong showers are under most of the EC islands. Be patient after this nasty episode an euphemisma...

[srainhoutx]

Appears the shear mentioned yesterday by forecaster Stewart is beginning to take hold of Tomas.

[KWT]

Wxman57, the key is exactly when and how sharp that turn is, really the best thing is for it to go NE as soon as possible, but even then its going to go through one of the Islands on the way through but given the state of Haiti, probably for the best if it can miss that country...

The sad thing is the models are converging on at least being close enough for lifethreating flooding and mud/landslides to occur.

[wxman57]

I'm afraid Haiti and the DR won't be able to escape a tragedy.

[SouthDadeFish]

31/1145 UTC 14.0N 62.9W T4.0/4.5 TOMAS -- Atlantic

[wxman57]

Doesn't look like a hurricane now on satellite.

[KWT]

Its presentation is still degrading, fair play on the ECM for picking up on possibly some major weakening from the shear....

Thats the worry wxman57, I'm afraid this thing will have to totally dissipate to not cause real problems and even then the left over moisture as it heads northwards towards the front would still cause issues...so its really sadly a lose-lose situation if the track remains close to the mark...

[cycloneye]

Shear will relax in 72 hours.

Code: Select all

ATLANTIC SHIPS INTENSITY FORECAST       *
                    *      GOES DATA AVAILABLE                  *
                    *      OHC  DATA AVAILABLE                  *
                    *  TOMAS       AL212010  10/31/10  12 UTC   *

TIME (HR)          0     6    12    18    24    36    48    60    72    84    96   108   120

SHEAR (KT)        19    18    23    25    21    22    17    15    11    10     3     9    12


[wxman57]

A big concern is the slowdown/stall just south of Haiti. If it stalls close enough to Haiti for the squalls to begin impacting on Tuesday and they last for over 2 days there, then the rainfall totals will be incredible. And THEN the center of the storm may pass right over them.

In the long run, I'd expect that it may well merge with the big storm over New England next weekend. Not as a hurricane, just as an energy contributor. Should make for some quite unseasonably cold and nasty weather for the northeast.