*******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.*********
...TUESDAY JULY 23 2024 3:30 PM EDT...

For the western Gulf of Mexico... including coastal northern Veracruz... coastal Tamaulipas... southeastern Texas... and Louisiana... the eastern divergence zone of an upper vortex that has been parked over northeastern Mexico and the southeastern divergence zone of an upper trough over central North America have been supporting regional thunderstorms and gradual formation of a tropical disturbance. However the CIMSS 850 mb vorticity product (https://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=vor&zoom=&time=) shows the low-level spin of the disturbance is elongated north-south while inland over northeastern Mexico and therefore tropical cyclone formation is not anticipated in the short-term. Over the next couple of days the northeastern Mexico upper vortex merges with the central North America upper trough... will watch to see if the surface tropical wave of low pressure currently approaching from Belize interacts with anticyclonic outflow on the west side of the currently developing Gulf of Mexico upper ridge and/or the eastern divergence zone of the aforementioned upper trough to produce an additional disturbance in the region in the days ahead.
For the central and western Caribbean... tropical development is not expected over the next few days due to lingering and suppressing cut-off upper vorticity. Over the next week a portion of the current central North America upper trough potentially merges with and re-enforces the central and western Caribbean upper vorticity... keeping tropical activity suppressed in this region (see mid-latitudes discussion below for more info on the future of the central North America upper trough).
For the eastern Caribbean and tropical belt of the Atlantic basin (Lesser Antilles to western Africa)... despite current upper ridging favoring tropical activity the models continue to not show tropical development perhaps while projecting that dry Saharan air will continue to blanket the region. A large/broad tropical wave of low pressure is currently near 42.5W longitude with the northwest side ingesting dry Saharan air and southeast side producing a thunderstorm cluster near 10N-37W. Satellite imagery suggests a second similarly large tropical wave of low pressure is currently emerging from western Africa while its southwest side produces a thunderstorm cluster near 10N-27.5W... its southeast side produces scattered thunderstorms over Senegal and vicinity... and while its northwest side ingests dry Saharan air. As such tropical development is not anticipated from either wave as both are ingesting dry Saharan air. In addition by day 7... some of the upper vorticity associated with the current north Atlantic upper trough may be pushed south toward the eastern tropical Atlantic (this is a result of amplification of the current northwest Atlantic upper ridge in the warm sector of what are now the surface frontal lows over the Great Lakes and northeastern US as those systems continue east across the north Atlantic... with the amplifying northwest/north Atlantic upper ridge pushing vorticity from the current north Atlantic upper trough southward toward the eastern tropical Atlantic). If true... this would help keep tropical activity calm in the eastern tropical Atlantic toward day 7.
For the middle and high-latitudes of North America and the Atlantic basin... over the next few days the hot air mass upper ridge that has been in place over western North America shifts east into the western Atlantic while becoming associated with the warm surface southerly flow ahead of a large-scale surface frontal system that progresses over western and eventually central North America... and also the warm surface southerly flow on the west side of the Atlantic surface ridge. Over the next 72 hours eastward-shifting hot air mass upper ridge pushes a polar upper vortex from north Canada into the north half of the current central North America upper trough... with the upper trough then splitting under the force of the upper ridge into a southwest half that slowly decays in the vicnity of Texas over the next several days and a northeast half that moves toward the north Atlantic. Eventually through day 7 the hot air mass upper ridge... as it arrives into the western Atlantic... potentially breaks the northeastern half of the upper trough into one large upper trough in the northeast Atlantic and a series of upper vortices lined parallel to the United States east coast... with one of these vortices potentially merging with and hence re-enforcing the stranded upper vorticity currently parked over the western/central Caribbean. Cannot rule out the possibility of a mid-latitude tropical disturbance offshore of the southeastern United States by day 7 which would be supported by the eastern divergence zone of one of the upper vortices. The surface trigger for such a disturbance would be the tail end of the current southeastern US surface front... as that surface front eventually is dragged eastward and offshore by the current Great Lakes and northeastern US surface frontal lows.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/).
0000Z (Jul 23) CMC Model Run...
**No tropical development shown in Atlantic basin through 168 hours (7 days)
0000Z (Jul 23) ECMWF Model Run...
**No tropical development shown in Atlantic basin through 168 hours (7 days)
1200Z (Jul 23) GFS Model Run...
**No tropical development shown in Atlantic basin through 168 hours (7 days)
0600Z (Jul 23) NAVGEM Model Run...
**No tropical development shown in Atlantic basin through 168 hours (7 days)
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