*******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.**********
...TUESDAY AUGUST 2 2022 12:20 PM EDT...
The Atlantic tropics are likely to remain generally calm through mid-August as the suppressing sinking motion phase of the Madden Julian Oscillation (MJO) has returned to the Atlantic basin (https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml). However some model runs... particularly the GFS as of late... still forecast lowering surface pressures in the southern Caribbean Sea within the next five days as follows:
(1) Over the previous several days thunderstorms and low surface pressures in the Caribbean have been suppressed by upper vorticity in the region.
(2) Their are early signs the cold core upper vorticity has begun to weaken while it remains cut-off from high-latitude cold air... as evidenced by an increase in thunderstorms in the southern Caribbean Sea this afternoon. This thunderstorm activity is enhanced by the outflow of a tropical upper ridge in the region which has begun to expand in the wake of the waning upper vorticity. Also note the thunderstorm activity is also enhanced by a passing surface tropical wave of low pressure now crossing the central Caribbean region.
(3) The upper trough currently crossing eastern North America has eroded the mid-latitude upper ridge that has been dominating the Atlantic basin. What remains of the mid-latitude upper ridge is a cell in the western Atlantic...and the upper vorticity currently in the Caribbean region is forecast to drift northward around the west side of this cell. The northward retreat of the upper vorticity will also allow the tropical upper ridge (with its supportive outflow conducive for thunderstorms and lowering surface pressures) in the southern Caribbean to further expand within the next five days.
(4) Will declare an area of interest for tropical development in the southern Caribbean in future updates as necessary... any disturbance that develops here is likely to cross Nicaragua and Costa Rica while bringing heavy rainfall with flash flooding potential.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
0000Z (Aug 2) CMC Model Run...
**No tropical cyclone formation forecast for the Atlantic basin for the next 168 hours (7 days)
0000Z (Aug 2) ECMWF Model Run...
**No tropical cyclone formation forecast for the Atlantic basin for the next 168 hours (7 days)
0600Z (Aug 2) GFS Model Run...
**Tropical low becomes briefly defined in the southern Caribbean near 11N-81W from 123 to 129 hours
0600Z (Aug 2) NAVGEM Model Run...
**No tropical cyclone formation forecast for the Atlantic basin for the next 168 hours (7 days)