Tropical Storm Henri forms
The tropics spawned another October surprise today, when Tropical Storm Henri formed in the face of adverse levels of wind shear. Henri is under about 20 - 25 knots of wind shear, which ordinarily prevents rapid development like we witnessed this afternoon. However, the environment is quite moist, and Henri is over warm waters, 29°C. An ASCAT pass from 11:37am EDT showed Henri had winds of 40 mph. Satellite loops show that Henri has managed to rapidly develop a large area of intense thunderstorms with cold cloud tops in just a few hours, though the high shear is keeping any thunderstorms from developing on the west side of the center. Water vapor satellite images show that there is some dry air to Henri's northwest, and this dry air will act to slow Henri's growth some. The dry air is creating strong downdrafts that are apparent on visible satellite images as arcs of cumulus clouds spreading out from where the downdraft hits the ocean surface, along the northwest side of Henri's center.
None of the reliable global computer models showed Henri would develop, and the models all favor weakening and dissipation of Henri by Thursday, due to high wind shear of 20 - 25 knots. The official NHC forecast goes along with this scenario, but think there is a medium (30 - 50% chance) that Henri will not dissipate. By Friday, wind shear in the vicinity of Henri (or its remains) is predicted to fall to the low to moderate range. Even if Henri has dissipated by that point, regeneration into a tropical storm may occur. The track of Henri after Friday is problematic, as the storm will be in an area of weak steering currents. Several of the models favor a track to the west-southwest into the Caribbean, across Hispaniola. Residents of the Dominican Republic and Haiti should anticipate that Henri or its remains may bring flooding rains to Hispaniola by Saturday. It is also possible that Henri will get pulled northwards and recurved out to sea, and not affect the Caribbean at all, though.
Figure 1. Latest satellite image of Henri.
A little tropical weather for England
The remnant circulation of Tropical Storm Grace is currently making landfall in Southwest England. Grace's remains brought sustained winds of tropical storm force--41 mph--to one buoy off the coast last hour, and 38 mph to the Sevenstones Lightship buoy. you can track the progress of Grace via our wundermap for the region.
Figure 2. The remnant circulation of Tropical Storm Grace scoots by to the south of Ireland in this visible satellite image taken at 1pm EDT 10/06/09. Image credit: UK Met Office.
Jeff Masters
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ABNT20 KNHC 070531
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
200 AM EDT WED OCT 7 2009
FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...
THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
STORM HENRI...LOCATED ABOUT 510 MILES EAST OF THE NORTHERN
LEEWARD ISLANDS.
ELSEWHERE...TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
PUBLIC ADVISORIES ON HENRI ARE ISSUED UNDER WMO HEADER WTNT35 KNHC
AND UNDER AWIPS HEADER MIATCPAT5. FORECAST/ADVISORIES ON HENRI ARE
ISSUED UNDER WMO HEADER WTNT25 KNHC AND UNDER AWIPS HEADER
MIATCMAT5.
$$
FORECASTER KIMBERLAIN
we on the blackout so the SSD pictures are 2hrs old
Thanks for the image link, TS.
Naked swirl is a good description. To the 'Naked Eye' he looks like he wants to organize.
I realize that but the loop from then shows a very exposed Henri....i doubt much has changed when looking at the shear.
well yeah
according to this it was really close to being exposed before blackout :)
Link above to Navy Microwave Image, click on 91L link on left. It will show you TS Henri pic from 0400 UTC, about 11PM CDT.
I also found out the hard way, Henri is French for Henry. I thought is was a female variation of Henry?!?
thanks =)
I really do hope the center is to the west of that convection xD
GFS showed this split happening the other day. One part of the energy headed NW towards the Bahamas and the southern part headed toward the Caribbean. Big props for the GFS if that were to pan out.
I'm not too sure the convection has been moving west with it.
5.30 utc
model runs.!!
it looks too good
maybe a LLC relocation?
well cant tell till we get some visible images in the Morning
Indeed, it's something to closely watch.
Regardless of whether or not Henri relocates his low-level center, the relentless southwesterly shear will ensure that it quickly becomes exposed again. I'll be surprised if this survives the next 48 hours.
I agree it will have to continue to fight if it wants to survive
It would have to stay at a due west movement here on out and then have to go wsw at some point to dodge Hispaniola and make it into the southern Caribbean. I don't see that happening right now. Shear is not as bad in the southern Caribbean. That is probably the only way Henri would survive.
got it now hmmm he really is starting to get a good shape at this hour could be 50 mph by what he looks like right now they may still bump him up again at 5am
and its satellite presentation has improved like I never thought it would
200910070600 18 -55.6 45
200910070000 18.1 -54.7 35
200910061800 17.7 -53.4 35
and with that im off to bed :0)
see you later
Blog Update
Tropical Storm Henri and the area to its southeast
Blob SE of Henri has a high over it(wishcaster).
Ike - not only are you rooting against Henri, but you are rooting for another invest eh? Trying to get yelled at by all bloggers?
Seriously - nice observation.
Blog Update
Tropical Storm Henri and the area to its southeast
I took your advise. I am going to return to surfing during the off-season but I hope we do get some decent waves from frontal waves passing to our north.
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