*******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 13 2020 7:18 PM EDT...
See area of interest section below for tropical wave currently entering the central Caribbean Sea from the eastern Caribbean. Elsewhere...the surface frontal low and upper vortex being pushed southward into the Azores by the deep-layered north Atlantic ridge is currently too broad and lacks thunderstorm activity to acquire tropical characteristics. The latest suite of model runs does not suggest that this system will develop a consolidated surfarce circulation needed for subtropical cyclone status as it eventually drifts eastward toward the much larger western Europe upper vortex or gets kicked eastward by a high-latitude upper trough that eventually erodes the north Atlantic ridge. Therefore not considering this weather system as an area of interest. And finally a tropical wave of low pressure currently offshore of the northern South America coast and approaching the southern Lesser Antilles is currently producing a large east-west area of thunderstorms with some rotation thanks to the support of upper outflow from a cell of tropcial upper ridging...but tropical development here is not expected as it will soon encounter outflow restriction and shear from the north induced by the southwest side of the large upper vortex in the western Atlantic.
AREA OF INTEREST #1...The once vigorous tropical wave that was east of the southern Lesser Antilles a couple of days ago is now entering the central Caribbean Sea. Off to the north...the remnants of a broad frontal low pressure from the central Atlantic and a surface front along the United States east coast are producing a surface ridge weakness that will tend to draw any surface low pressure spawned from the tropical wave on a more northwest track toward Cuba and the western Bahamas in the coming days. Early signals for upper air support for such a surface low pressure include a batch of thunderstorms between Nicaragua and Jamaica off to the west being generated by another tropical wave interacting with the eastern divergence zone of the remnants of a northwestern Caribbean upper vortex...with this upper air pattern shifting northward toward Cuba and the western Bahamas as the remains of the upper vortex merges with the south part of the eastern North America upper trough...with the south half of the upper trough eventually cutting off into an upper vortex over the southeastern United States as a longwave upper ridge pattern builds over the central United States. The CMC and ECMWF are beginning to pick up on this pattern by now forecasting a surface low pressure to be offshore of the southeastern United States in the 4 to 5 day timeframe...perhaps as a broad surface low pressure spawned by the tropical wave lifts northward from the western Bahamas while supported by the eastern divergence zone of the southeastern United States upper vortex. The GFS and NAVGEM meanwhile do not show this solution...with the GFS suggesting the southeast US upper vortex being at a further north position to generate southwesterly wind shear unfavorable to tropical development. For now have only 5% odds of tropical cyclome development offshore of the southeatern United States in the 4 to 5 day timeframe due to the overall lackluster computer model support.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (1800Z Jun 14)...0% chance of tropical cyclone formation (between Haiti and Jamaica near 18.5N-75.5W)
IOH 48 Hr Outlook (1800Z Jun 15)...0% chance of tropical cyclone formation (eastern Cuba near 20.5N-78W)
IOH 72 Hr Outlook (1800Z Jun 16)...0% chance of tropical cyclone formation (western Bahamas near 25N-78W)
IOH 96 Hr Outlook (1800Z Jun 17)...5% chance of tropical cyclone formation (offshore of the southeastern United States near 30N-76W)
IOH 120 Hr Outlook (1800Z Jun 18)...5% chance of tropical cyclone formation (southeast of Cape Hatteras North Carolina near 34N-75W)
...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 area of interest #1...no tropical cyclone formation shown...but a weak surface low pressure shown offshore of the southeastern United States between 108 to 138 hours. Elsewhere...broad frontal low pressure currently north of the Azores arrives over the eastern islands in 12 hours...cyclonically loops beneath its supporting cut-off upper vortex and over the Azores thru 48 hours...swings east-southeast and weakens to a surface trough just northwest of the Canary Islands by 102 hours.
1200Z ECMWF Model Run...For area of interest #1...no tropical cyclone formation shown...but a broad weak low pressure is shown offshore of the southeastern United States at 96 hours which makes landfall on the North Carolina coast by 120 hours. Elsewhere...broad frontal low pressure currently north of the Azores arrives over the islands by 24 hours...drifts to a position south of the Azores by 72 hours...swings east-southeast and weakens to a surface trough between the Azores and Canary Islands by 96 hours.
1200Z GFS Model Run...For area of interest #1...no tropical cyclone formation shown...perhaps a weak surface trough shown offshore of the southeastern United States at 72 hours. Elsewhere...broad frontal low pressure currently north of the Azores arrives over the islands by 18 hours...drifts to a position southwest of the Azores by 72 hours...swings east-southeast and weakens to a surface trough over the northern Canary Islands by 138 hours.
1200Z NAVGEM Model Run...For area of interest #1...no tropical cyclone formation shown. Elsewhere...broad frontal low pressure currently north of the Azores arrives over the islands by 24 hours...drifts to a position south of the Azores by 78 hours...swings east-southeast and weakens to a surface trough just northwest of the Canary Islands by 102 hours.
Comments