ATL : EX TOMAS - Discussion

[TampaFl]

Met Service Of Jamaica Radar Loop - Tomas

Follow Tomas on the long range radar out of Kingston, Jamaica. The loop will start automaticlly after loading.

http://www.metservice.gov.jm/radarpage2.asp

Robert

[cycloneye]

Lowest pressure is 997 mbs on last pass by Air Force plane.

[KWT]

The main risk is clearly involving heavy rains for most of Haiti, in some ways the best thing that could happen is shear decrease loads, because that'd help it to relocate its convection over the center and away from Haiti, ironically the worst case would be if the shear got a little stronger and detached the convection further east away from the center again...

Still it does look like its in a restrengthening phase, whether it makes it to hurricane strength again is something that remains uncertain, though on a NNE heading its more likely then not I tend to find...

Feels like we've had Tomas for quite a while now!

[cycloneye]

Decoded last vortex message by Air Force plane.The mission is over.

Product: Air Force Vortex Message (URNT12 KNHC)
Transmitted: 4th day of the month at 11:20Z
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: 13
Observation Number: 20
A. Time of Center Fix: 4th day of the month at 11:08:00Z
B. Center Fix Coordinates: 15°50'N 76°02'W (15.8333N 76.0333W) (View map)
B. Center Fix Location: 158 miles (254 km) to the SSE (161°) from Kingston, Jamaica.
C. Minimum Height at Standard Level: 1,402m (4,600ft) at 850mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 30kts (~ 34.5mph)
E. Location of the Estimated Maximum Surface Wind: 16 nautical miles (18 statute miles) to the NE (48°) of center fix
F. Maximum Flight Level Wind Inbound: From 117° at 41kts (From the ESE at ~ 47.2mph)
G. Location of Maximum Flight Level Wind Inbound: 36 nautical miles (41 statute miles) to the NE (47°) of center fix
H. Minimum Sea Level Pressure: 998mb (29.47 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 17°C (63°F) at a pressure alt. of 1,522m (4,993ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 20°C (68°F) at a pressure alt. of 1,520m (4,987ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 15°C (59°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 Level: 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: 41kts (~ 47.2mph) in the northeast quadrant at 10:56:50Z
Remarks Section - Additional Remarks...
RADAR PRESENTATION IMPROVING WITH MULTIPLE BANDING ON EASTERN SIDE

[KWT]

Looks like the winds probably aren't quite as high as the NHC believe they are based on that particular pass, though I'm not sure what leg that was?

[Canerecon]

"Miss Piggy" (NOAA) is taking their place.

[tolakram]

Tomas is sheared and it appears shear will stay the same or get worse as Tomas moves north. Not sure why they expect a hurricane ... will watch and see.

[wxman57]

Tomas is sheared and it appears shear will stay the same or get worse as Tomas moves north. Not sure why they expect a hurricane ... will watch and see.

I see the same thing - increasing southwesterly shear as the jet core associated with the cold front approaches. Center is on the western side of the convection.

[Battlebrick]

240mb 220° (from the SW) 92 knots (106 mph)

I know thats a really high elevation.. but could it mean anything in the future or is it just because its really high lol.

Edit: ok nevermind LOL 151mb 270° (from the W) 493 knots (567 mph)

[SouthDadeFish]

Recon is finding a dropping pressure....

[wxman57]

Seems like they're tracking several centers rotating around a larger open low pressure area. I can see one little vortex rotating southward near 15N. Tomas is taking on the classic sheared comma pattern now. Good news for Jamaica, bad for Haiti.

[SouthDadeFish]

Tomas is clearly being sheared, but nice banding is developing in the E semicircle.

http://rammb.cira.colostate.edu/ramsdis/online/loop_640.asp?product=tropical_ge_4km_visir2_floater_1

[SouthDadeFish]

Product: NOAA Vortex Message (URNT12 KWBC)
Transmitted: 4th day of the month at 14:25Z
Aircraft: Lockheed WP-3D Orion (Reg. Num. N43RF)
Storm Number & Year: 21L in 2010
Storm Name: Tomas (flight in the North Atlantic basin)
Mission Number: 15
Observation Number: 13
A. Time of Center Fix: 4th day of the month at 13:49Z
B. Center Fix Coordinates: 16°3'N 76°8'W (16.05N 76.1333W)
B. Center Fix Location: 141 miles (227 km) to the SSE (162°) from Kingston, Jamaica.
C. Minimum Height at Standard Level: 3,083m (10,115ft) at 700mb
D. Estimated (by SFMR or visually) Maximum Surface Wind: 30kts (~ 34.5mph)
E. Location of the Estimated Maximum Surface Wind: 2 nautical miles (2 statute miles) to the W (269°) of center fix
F. Maximum Flight Level Wind Inbound: From 18° at 22kts (From the NNE at ~ 25.3mph)
G. Location of Maximum Flight Level Wind Inbound: 34 nautical miles (39 statute miles) to the W (269°) of center fix
H. Minimum Sea Level Pressure: 997mb (29.44 inHg)
I. Maximum Flight Level Temp & Pressure Altitude Outside Eye: 11°C (52°F) at a pressure alt. of 3,062m (10,046ft)
J. Maximum Flight Level Temp & Pressure Altitude Inside Eye: 15°C (59°F) at a pressure alt. of 3,063m (10,049ft)
K. Dewpoint Temp (collected at same location as temp inside eye): 10°C (50°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, Wind, Pressure and Temperature
N. Fix Level: 700mb
O. Navigation Fix Accuracy: 1 nautical mile
O. Meteorological Accuracy: 1 nautical mile
Remarks Section:
MAX OUTBOUND AND MAX FL WIND 38 KTS E QUAD 1404Z
CNTR DROPSONDE HAD WINDS 085/43 AT SPLASH
ALL CONVECTION IN EAST SEMICIRCLE

Stronger temp differential than the previous VDM. Interesting note from the center dropsonde as well.

[jconsor]

No question the shear is preventing Tomas from developing a well defined inner core. However, CIMSS analyses show the shear vector has shifted from WSW to SW in the past few hours, and it's forecast to shift to SSW in the next 6 hours. That will help reduce the storm-relative shear, since Tomas is now moving N and is forecast to turn to the NNE.

However, I don't think we'll see any substantial intensification until later Thu night, when Tomas accelerates to over 10 kt and moves more in line with the mean flow. Right now his forward speed is about 3 kt.

I see the same thing - increasing southwesterly shear as the jet core associated with the cold front approaches. Center is on the western side of the convection.

[HURAKAN]

Latest

[KWT]

Yeah thats a classic sheared comma shape, or in other words, the lopsided storm. Thats worrying to see because any sort of east of north motion is going to put the convection right over Haiti.

Probably strengthening a little but not much...

[wxman57]

No question the shear is preventing Tomas from developing a well defined inner core. However, CIMSS analyses show the shear vector has shifted from WSW to SW in the past few hours, and it's forecast to shift to SSW in the next 6 hours. That will help reduce the storm-relative shear, since Tomas is now moving N and is forecast to turn to the NNE.

However, I don't think we'll see any substantial intensification until later Thu night, when Tomas accelerates to over 10 kt and moves more in line with the mean flow. Right now his forward speed is about 3 kt.

I see the same thing - increasing southwesterly shear as the jet core associated with the cold front approaches. Center is on the western side of the convection.

Agree on the intensification. Even though the NHC is saying shear is light, Tomas doesn't give the appearance of being in a light shear environment. I went with max winds of 55 kts as it passes Haiti, and that might be generous. Probably has a better chance of racing northward and being absorbed into the low off New England, too.

[KWT]

I think 50-60kts sounds about right Wxman57, if only because many times in the past these comma type TCs tend to be a little stronger then thier presentation let on...

[HURAKAN]

Latest

[Sanibel]

Looks like the wind threat is down. The question now is track and rain amounts over Haiti.



Tomas got disorganized by the East Caribbean and couldn't rebound.