*******Note that forecast and outlooks in this post are NOT the official forecast from the National Hurricane Center (NHC). They are my own detailed views on the Atlantic tropics based on current observations and latest computer model runs. As such do not make decisions based on my posts...consult news media...watches and warnings from your local weather office...and any evacuation orders issued by local governments to make the most informed and best decisions. Visit the NHC website hurricanes.gov (hurricanes dot gov) for the latest watches/warnings and official forecasts on active tropical cyclones.*********
...FRIDAY AUGUST 30 2024 10:19 PM EDT...
The following is a special update on the northwestern Gulf of Mexico area of disturbed weather which has been upgraded to an area of interest for possible tropical development by the National Hurricane Center as of 2 PM EDT this afternoon. For information on tropical activity elsewhere in the Atlantic basin… including area of interest #19 which is expected to cross the Lesser Antilles islands by early this upcoming week… refer to full update #79 (https://www.infohurricanes.com/post/my-2024-atlantic-hurricane-season-birdseye-view-post-79)
AREA OF INTEREST #22… Satellite image of the current northwest Gulf tropical low pressure… taken at 2356Z:
Before dissipating tonight… the divergence zone of the upper-level trough that was over Texas spent the last couple of days developing persistent showers and thunderstorms… and more recently a low-level low pressure spin near coastal Texas and Louisiana. The latest CIMSS 850 mb vorticity product (https://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=vor&zoom=&time=) suggests a SW/NE oriented oblong circulation along coastal SE Texas extending to the SW corner of Louisiana with the centroid just offshore of the Texas/Louisiana border. Satellite animation suggests the centroid is drifting east into waters just offshore of Louisiana while dragged by the tail end of the surface cold front associated with the currently developing frontal cyclone. Because of the offshore turn the NHC has upgraded this disturbance to an area of interest for possible tropical cyclone formation… the twenty-second tracked on this site this year.
My forecast track in the outlook below has the surface low drift east for another 12 hours… followed by a reversal to a westward drift from 12 to 24 hours due to a weak central US surface ridge to the north to be supported by the convergence on the back side of the Canadian frontal cyclone’s upper trough tail. It appears by 48+ hours a stronger surface ridge that dives south from Canada… to be supported by the stronger convergence zone of the upper trough’s main body… should accelerate this system faster to the west into southeastern Texas which is why I end the outlook by 72 hours. The recent statements in the NHC outlook suggest this system could linger over coastal waters for longer than what I show… however I don’t see how that’s possible unless this system becomes strong/tall enough to be dragged by the upper westerlies that would counteract the surface steering. For now the shear induced by the upper westerlies is keeping showers and thunderstorms east of the tropical low’s center… and as of this writing the activity has weakened. Thus I do not see a scenario where this system is becoming stronger/taller… and due to the recent negative effects of the shear… with the shear forecast to persist over the next few days… I only have peak odds of tropical cyclone formation set at 10%. Regardless of tropical cyclone formation or not… southeast Texas and southern Louisiana may now see more rainfall over the next couple of days which could increase flooding risk as persistent rains have already occurred in this region in the days prior.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (0000Z Sep 1)... 10% chance of tropical cyclone formation (just offshore of the Texas/Louisiana border near 29N-93.8W)
IOH 48 Hr Outlook (0000Z Sep 2)… 10% chance of tropical cyclone formation (vicinity of Galveston Bay Texas near 29N-95W)
IOH 72 Hr Outlook (0000Z Sep 3)… 0% chance of tropical cyclone formation (inland southeastern Texas near 29N-97.5W)
*****National Hurricane Center (hurricanes.gov) official outlook as of 8 PM EDT***************************
Formation chance through 48 hours... 10%
Formation chance through 7 days... 20%
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