*******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.**********
...FRIDAY AUGUST 14 2020 2:25 PM EDT...
The following is a special update on the rapidly organizing surface low pressure center now located northeast of the North Carolina coast. Since birdseye view post #91 issued earlier this morning...the thunderstorm bands covering the center of low pressure and areas east of the center have become better organized. The ASCAT pass system appears to be down (https://manati.star.nesdis.noaa.gov/datasets/WindSATData.php)...but based on the above WINDSAT image there appears to be a wind vector approaching tropical storm force (35 knots or 40 mph). Given that the WINDSAT is a lower resolution system than ASCAT and that the WINDSAT image is a bit outdated...I estimate based on the current organization that the current strength of this system is a bit higher at 45 mph maximum sustained winds. Thus I am assuming that a tropical storm appears to be forming...and I have issued a tropical cyclone formation forecast as outlined below. In the next 24 hours I assume that despite increasing wind shear from the upper trough associated with the incoming frontal zone to the northwest that this system will strengthen further to 60 mph maximum sustained winds...due to supportive upper divergence induced by the southeast side of the upper trough and upper outflow extending to the south to be induced by warm upper ridging ahead of the front. It is also possible the shear will be lessened by the accelerating east-northeast track of this system which will keep the forward motion of this system aligned with the shearing upper westerly winds. By 48 hours I expect the frontal zone will have overspread the circulation and transition this system to a fully non-tropical feature. After that time a rapidly intensifying and large northeastern Atlantic frontal cyclone may dominate and potentially absorb this system...see birdseye view post #91 for more details on this. Another possiblity suggested by the 0000Z ECMWF and now more recently the latest 1200Z GFS model run is that this system will merge and then absorb the early phase of the northeastern Atlantic frontal low and explosively intensify into the dominant non-tropical frontal cyclone in the region. This system appears to be consolidating further to the northeast...therefore my forecast track points are once again adjusted northeast...also to keep up the 1200Z GFS that also shows a faster east-northeast track compared to the 0600Z run.
******Infohurricanes.com forecast. Visit hurricanes.gov (hurricanes dot gov) for official forecast***********
0 Hr Position (1800Z Aug 14)...Surface low pressure centered offshore of the mid-Atlantic United States coast at 36.5N-72.5W
IOH 24 Hr Forecast (1800Z Aug 15)...60 mph maximum sustained wind tropical storm centered in the northwestern Atlantic at 39N-68W
IOH 48 Hr Forecast (1800Z Aug 16)...Remnant gale force frontal low pressure centered in the northwestern Atlantic at 42N-59W
Comments