*******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.**********
…MONDAY JUNE 6 2022 8:30 PM EDT...
Tropical Storm Alex transitions into a remnant non-tropical frontal cyclone in the open central Atlantic… see Alex section below for more information. Elsewhere… the tropical upper ridge currently over the Caribbean and eastern Pacific will be the focus 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 in the Gulf of Mexico to be left behind by the current southeast US shortwave upper trough. Gulf of Mexico upper vorticity will be re-enforced by days 4 and 5 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 5… 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. Long-range model runs suggest potential western Caribbean development in approximately one week from today… and will consider tagging a new area of interest in this region in future updates should these model trends continue.
REMNANTS OF ALEX…After swiping Bermuda with tropical storm conditions with its south side… Tropical Storm Alex as of 5 PM EDT has transitioned to a remnant non-tropical frontal cyclone after pulling east-northeast away from Bermuda. Observations from the Bermuda weather service (http://www.weather.bm/observations.asp) have shown that sustained winds and gusts have dropped below tropical storm force through the afternoon and evening hours as weather conditions improve in the wake of Alex. The transition of Alex to a frontal cyclone was supported by water temps below 26 deg C… ingestion of drier and cooler air behind the front to the north that Alex has been merging with… and the eastern divergence zone of upper vorticity that has recently ejected from the central Canada upper vortex which has kept Alex at cyclone strength. Models agree that this upper vorticity will soon merge with vorticity to dive south from the current polar upper vortex over Greenland… resulting in an amplified North Atlantic upper trough whose eastern divergence zone will help keep Alex’s remnant frontal cyclone strong. Models also agree on bringing the cyclone into the waters between Iceland and the British Isles by day 5. As such… expect increasing coastal sea swells for the British Isles and Iceland by Friday and Saturday. Gusty winds in Iceland and the northern British Isles are possible by Saturday.
This is my final statement on Alex on this blog as it is no longer a tropical system. Information on Alex’s impacts later this week as a remnant frontal cyclone will be carried on the home page bulletins of this site.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
1200Z CMC Model Run...
**For Remnants of Alex… remnant frontal cyclone continues northeast and reaches waters between Iceland and the British at 120 hours
**Broad low pressure becomes defined over Honduras at 150 hours… becomes possible tropical depression offshore of Honduras and Belize at 168 hours
1200Z ECMWF Model Run...
** For Remnants of Alex…remnant frontal cyclone continues northeast and reaches waters between Iceland and the British at 120 hours
1200Z GFS Model Run...
** For Remnants of Alex… remnant frontal cyclone continues northeast and reaches waters between Iceland and the British at 120 hours
**Compact eastern Pacific tropical cyclone formation forecast just offshore of Honduras at 108 hours… drifts north into the Honduras coast at 120 hours for a landfall… broad low pressure containing the remnants of the eastern Pacific tropical cyclone becomes defined on the north coast of Honduras at 135 hours… drifts northwest into the Caribbean waters offshore of northern Belize through 168 hours
1200Z NAVGEM Model Run...
** For Remnants of Alex…remnant frontal cyclone continues northeast and reaches the north side of the British Isles at 120 hours
** Broad low pressure becomes defined over the northeast coast of Honduras at 144 hours… moves northwest into the western Caribbean Sea at 168 hours