MY 2021 ATLANTIC HURRICANE SEASON BIRDSEYE VIEW POST #136
*******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.**********
…THURSDAY OCTOBER 14 2021 1:30 AM EDT...
Satellite image as of 0120Z. Areas of interest circled in yellow are not mentioned in the NHC tropical weather outlook. Areas circled in a green dashed line are in the NHC 5-day tropical weather outlook. Areas circled in a solid green line are in the NHC 2-day tropical weather outlook:
NHC TAFB Surface Analysis 1800Z (Wednesday Oct 13):
GFS Model Upper-Level Winds 1800Z (Wednesday Oct 13):
See area of interest section below for an update on the tropical disturbance now drifting eastward away from the southeastern Bahamas. It is quiet elsewhere in the Atlantic tropics.
AREA OF INTEREST #1… The surface trough of low pressure near the southeastern Bahamas… supported by the upper divergence zone of the upper vorticity currently over the western Bahamas… has developed a defined low pressure spin in the low clouds located near 25N-70W. The low pressure is drifting east away from the Bahamas under the steering influence of another surface low pressure to the north… which is the remnants of the subtropical disturbance that was offshore of North Carolina a couple of days ago. The eastward drift is also expected to continue due to an eastward-shifting surface ridge weakness to be driven by the eastern divergence zone of the upper trough to arrive from its current position over southeastern Canada. Showers and thunderstorms associated with this disturbance have come to an end over land areas to shearing upper southwesterly winds ahead of the western Bahamas upper vorticity which have carried the thunderstorm activity eastward and away. The shear is only expected to worsen by 24 hours with the approach of the upper trough from southeastern Canada… which will make conditions hostile for tropical development. Therefore I have lowered my odds of tropical cyclone development from this disturbance to 0%… and this is my final statement on this disturbance on this blog unless it continues to be mentioned in the NHC tropical weather Outlook by my next update.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (0000Z Oct 15)… 0% chance of tropical cyclone formation (western Atlantic near 25N-67.5W)
...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… surface low becomes elongated east-west by 42 hours with the east end becoming a non-tropical frontal low in the long range
1200Z ECMWF Model Run...
**For area of interest #1… located at 31N-45W as a non-tropical frontal low at 72 hours
1800Z GFS Model Run...
**For area of interest #1… surface low becomes elongated east-west by 33 hours with the east end becoming a non-tropical frontal low in the long range
1800Z NAVGEM Model Run...
**For area of interest #1… develops into a surface low near 25N-70W at 24 hours… becomes elongated east-west by 60 hours with the east end becoming a non-tropical frontal low in the long range.