MY 2021 ATLANTIC HURRICANE SEASON BIRDSEYE VIEW POST #65
*******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 JULY 31 2021 12:37 AM EDT...
Satellite image as of 0350Z. 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:
GFS Model Upper-Level Winds 1800Z:
The cold front that has entered the northwest Atlantic from the eastern US…while driven by a new frontal low over southeast Canada…currently lacks significant thunderstorm activity. The ECMWF model has also backed off in showing tropical development along this front despite the potential for the front to decay below an offshore extension of the current southern United States sprawling upper ridge creating an environment of low shear and upper outflow. Therefore I have not declared the front an area of interest for tropical development.
Elsewhere…conditions in the low-latitudes of the tropical Atlantic will soon return to a more favorable state as the upward-motion phase of the Madden Julian Oscillation (MJO) is shifting east into the Atlantic basin (https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/mjo.shtml). All global computer models agree on showing lowering surface pressures in the eastern tropical Atlantic by 4 to 7 days...perhaps a signature of vigorous tropical waves of low pressure emerging from Africa and being aided by the MJO's arrival and also the outflow and divergence of the eastern tropical Atlantic upper ridge axis forecast to perist over the next several days. Therefore an area of interest may emerge in the eastern tropical Atlantic in the coming days.
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
1200Z CMC Model Run...no tropical cyclone formation shown in the Atlantic basin for the next seven days (168 hours)
1200Z ECMWF Model Run...
**Along cold front currently entering northwest Atlantic…a strong low pressure forecast to form near 42N-67.5W at 72 hours…however structure of low pressure is more elongated than previous runs suggesting a less tropical low pressure stretched along the front.
**Strong tropical wave of low pressure enters the eastern Atlantic from Africa in next 24 hours…develops a broad low pressure spin near 11.5N-35W at 96 hours…center of spin reaches 13.5N-48.5W by 144 hours.
1800Z GFS Model Run... no tropical cyclone formation shown in the Atlantic basin for the next seven days (168 hours)
1200Z NAVGEM Model Run...strong tropical wave of low pressure emerges from Africa at 96 hours…tropical cyclone formation suggest just offshore of Africa near 15.5N-18W at 114 hours…while drifting very slowly northwest tropical cyclone weakens to a remnant low by 168 hours while still located between the Republic of Cabo Verde Islands and west African coast.