*******Note that forecasts 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.**********
…WEDNESDAY JUNE 8 2022 11:16 PM EDT...
The tropical upper ridge currently over the Caribbean and eastern Pacific will be a focal point for potential tropical development in the days ahead due to its favorable low shear and upper outflow environment:
(1) In the short-term the upper ridge will be suppressed southward toward the eastern Pacific due to cut-off upper vorticity currently in the Gulf of Mexico. This vorticity will be re-enforced by days 2 and 3 by a passing additional shortwave upper trough to eject from the current northeast Pacific upper vortex. See the NHC website hurricanes.gov (hurricanes dot gov) for coverage of any potential eastern Pacific development as this site is dedicated to Atlantic tropical activity.
(2) After day 3… the northeast Pacific upper vortex is forecast to finally shift into western North America where with its eastern divergence zone generates a strong surface frontal system. The warm sector of the frontal system is expected to build a central US upper anticyclone that will push the Gulf of Mexico upper vorticity westward and away… allowing the tropical upper ridge to expand back northward into the western Caribbean. Will be watching for possible western Caribbean development in approximately 6 to 7 days from today… will tag an area of interest in this region in future updates should computer model runs or current observations warrant.
Elsewhere… a pair of cold fronts to emerge into the western Atlantic from the eastern United States in the days ahead may also require monitoring for tropical development… an additional area of Interest may be tagged in future updates as necessary:
(1) A Great Lakes shortwave upper trough currently pivoting across the south side of the current central Canada upper vortex will drive the current eastern US cold front into the western Atlantic in 48 to 72 hours. Tropical development risk appears low due to wind shear to be induced by the additional shortwave upper trough to eject from the northeastern Pacific upper vortex which will pivot across the eastern US during this time… with development only being shown by the CMC model at this time.
(2) A batch of upper vorticity to separate from the northeast Pacific upper vortex at 60 hours will merge with the Central Canada upper vortex… resulting in an amplified upper trough that eventually drives a second cold front into the western Atlantic from the eastern US in approximately 6 days. The potential for tropical development along the tail end of this second front… at a location offshore of the southeastern US… at this time appears higher as wind shear is expected to be low.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
1200Z CMC Model Run...
**Current cold front over the eastern US leaves a surface low pressure just offshore of South Carolina at 48 hours… surface low becomes better defined offshore of North Carolina at 66 hours… becomes more elongated and less tropical offshore of Massachusetts at 84 hours and loses identity offshore of Newfoundland at 108 hours.
**Additional cold front moves offshore of eastern US at 144 hours… possible tropical development at tail end of front near 30.5N-76.5W at 168+ hours
**Tropical low becomes defined over Honduras at 120 hours… moves west-northwest to Bay of Campeche coast of Mexico through 168 hours
1200Z ECMWF Model Run...
** No Atlantic tropical development shown in the next 168 hours (7 days)
1800Z GFS Model Run...
** East-west elongated low pressure becomes defined over northeastern Honduras at 138 hours… develops a better-defined center on the north coast of Honduras at 159 hours… better defined center moves west-northwest across western Caribbean and makes landfall in northern Belize at 168 hours
1200Z NAVGEM Model Run...
** At 66 hours… tropical low pressure develops in the southern Caribbean while a tropical cyclone develops in the eastern Pacific just offshore of Costa Rica… through 96 hours the southern Caribbean low loses dominance while eastern Pacific tropical cyclone moves northwest into El Salvador… remnants of eastern Pacific cyclone move northwest across Honduras… Belize… and the southern Yucatan peninsula through 132 hours… moves northwest across Bay of Campeche while developing into a tropical cyclone by 144 hours.