Discussion on the Tropical Storm Ernesto Forecast…

Discussion on the Tropical Storm Ernesto Forecast

Corrected National Hurricane Center (NWS) for Tropical Storm Ernesto at Miami, Florida (AL052024) Discussion Number 27

August 18, 2024, at 500 AM AST

Updated the second important message’s text.

Ernesto’s cloud pattern isn’t very different from before, and it doesn’t have a distinct eye feature. The system appears somewhat symmetrical overall because deep convection has been attempting to encircle the eastern part of the circulation. As of right now, the intensity estimate is at 60 kt, which is consistent with the most recent objective, AID, values obtained from UW-CIMSS. Dvorak satellite estimates that are subjectively lowered. Regretfully, the majority of the circulation was overlooked by the scatterometer overpasses in recent times.

With an estimated initial speed of 025/8 kt, the tropical storm is still moving slowly toward the north-northeast. The direction of flow on the east side of a large mid-tropospheric trough approaching
the U.S. east coast should cause an increase in forward speed during
the next day or so along with a turn toward the northeast. In 2-3
days, Ernesto is likely to turn toward the east-northeast with
additional acceleration as it becomes embedded in the mid-latitude
westerlies over the north Atlantic. The track guidance models
remain in good agreement, and little changes to the previous NHC
track forecast were required.

Ernesto is still over warm waters and is expected to stay over SSTs of about 27 degrees Celsius for the next day or so. Additionally, today’s forecast for vertical wind shear is at lower levels with upper-level divergence.

identified by the SHIPS model diagnostics across the region. The official prediction reflects the favorable environmental conditions that favor a brief period of strengthening today. The cyclone is expected to weaken when it approaches far cooler waters in the next 36 to 48 hours. By the time the system approaches close to Newfoundland, simulated infrared satellite data from the global models reveals an increasingly asymmetric cloud structure, and the official forecast implies a 48-hour post-tropical transition. It is expected that Ernesto will expand and transform into a sizable depression across the northern Atlantic.