*******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 MARCH 22 2021 11:00 PM EDT...
Satellite Image of frontal low pressure offshore of the Carolinas:
The upper trough and surface frontal system that produced severe weather on the 18th and 19th of March over the southern and southeastern US has moved offshore...with the north half of this upper trough now in the northeast Atlantic and south half of this upper trough offshore from the eastern US coastal region. The eastern divergence zone of the upper trough offshore of the eastern US has been producing an elongated frontal surface low pressure located offshore of the southeastern US this past weekend...with this frontal low trapped stationary by a surface ridge to the northeast supported by the western convergence zone of the northeast Atlantic upper trough.
The elongated frontal low pressure as of this past afternoon and evening has produced a compact and consolidated spin offshore of the Carolinas confirmed by ASCAT passes....with a small clump of persisting thunderstorms supported by 20 to 22 deg C Gulf Stream waters and cold enough upper air temperatures (200 mb heights currently measure 1200 dekameters in the area). Models agree that this surface low will remain generally stationary over the next 24 hours as the trapping surface ridge to the northeast becomes re-enforced by the western convergence zone of the eastern US coastal upper trough as that trough ejects eastward. This eastward ejection of the upper trough should also place the surface low under the western convergence zone of the upper trough...which should cause the surface low to lose thunderstorms and weaken. Therefore subtropical cyclone formation is not likely and this is my planned only statement on this disturbance.