*******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.**********
…SATURDAY JUNE 11 2022 12:37 AM EDT...
The tropical upper ridge currently over the southern 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) Currently the upper ridge is suppressed southwestward toward the eastern Pacific due to cut-off upper vorticity currently over western Cuba. This vorticity will be re-enforced in the next 24 hours by the current central US shortwave upper trough… as this shortwave upper trough passes near the Gulf of Mexico and over the eastern US. In addition to the current eastern Pacific area of interest being monitored by the NHC near 100W longitude… recent model runs are latching on to a second possible eastern Pacific tropical disturbance in the short-term. This is likely related to the current southern Caribbean thunderstorms east of Nicaragua which have been triggered by upper divergence between the tropical upper ridge and western Cuba upper vorticity… which could shift west across Central America and into the eastern Pacific as the upper vorticity shifts west (see bulletin below as to why the upper vorticity is expected to shift west). See the NHC website hurricanes.gov (hurricanes dot gov) for more information on potential eastern Pacific development as this site is dedicated to Atlantic tropical activity.
(2) At 48+ hours… the current northeast Pacific upper vortex is forecast to shift into western North America where with its eastern divergence zone it 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 western Cuba and Gulf of Mexico upper vorticity westward and away… allowing the tropical upper ridge to expand back northward into the western Caribbean. In approximately 5 days… tonight’s 18Z GFS model run forecasted some of the upper vorticity to be trapped near the northern Yucatan peninsula while the current upper vorticity near the Lesser Antilles also approaches from the east under the influence of the US upper anticyclone… with this pair of upper vorticity lobes further enhancing the outflow of the western Caribbean portion of the tropical upper ridge. This could result in a western Caribbean tropical disturbance in the days ahead.
(3) The GFS is the only remaining model forecasting western Caribbean tropical development while other models have trended away from such a solution. Should other models later re-join the GFS… or if later observations warrant… a western Caribbean area of interest could be declared in future updates.
Elsewhere… a batch of western Canadian upper vorticity is in the process of separating from the current northeast Pacific upper vortex and will later merge with the current central Canada upper vortex…. resulting in an amplified upper trough over eastern Canada that slides into the North Atlantic. This upper trough is expected to drive a surface cold front into the western Atlantic from the eastern US in approximately 4 days. The potential for tropical development along the tail end of this front… at a location offshore of the southeastern US… at this time appears possible as wind shear is expected to be low due to the approach of a forecast central US upper anticyclone (see above discussion about possible Caribbean development for the expected origin of the anticyclone). Will consider adding this frontal system as an area of interest for tropical development in future updates.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
1200Z (Jun 10) CMC Model Run...
** No Atlantic tropical development shown in the next 168 hours (7 days)
1200Z (Jun 10) ECMWF Model Run...
** No Atlantic tropical development shown in the next 168 hours (7 days)
1800Z (Jun 10) GFS Model Run...
**Eastern Pacific tropical cyclone develops offshore of Mexico near 100W longitude at 63 hours and makes landfall at 111 hours while continuing north toward the ridge weakness induced by western North America frontal system… pair of tropical lows subsequently develop at 126 hours with one located in the Caribbean just offshore of the Nicaragua/Honduras border and another located in the eastern Pacific just offshore of Guatemala/Mexico border… through 147 hours the stationary eastern Pacific low becomes a second eastern Pacific tropical cyclone while the westward-moving Caribbean low becomes a tropical cyclone offshore of northern Honduras… by 168 hours both tropical cyclones make landfall while in close proximity to each other (eastern Pacific landfall just west of the Guatemala/Mexico border and Caribbean landfall over northern Belize
1200Z (Jun 10) NAVGEM Model Run...
** No Atlantic tropical development shown in the next 168 hours (7 days)