Monitoring Hurricane Larry Closely

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Hurricane Larry is forecast to reach category-3 major hurricane intensity BEFORE reaching 84-85F water surface in the western North Atlantic basin. The concern is a larger and more intense storm may resist (initially) a north to northeast turn leaving the U.S. East Coast at risk of a nearby major hurricane.

Fig. 1: Latest 5-day forecast track of Hurricane Larry forecast to gain major hurricane status tomorrow.

Fig. 2: Tropical cyclone model tracks forecast for Hurricane Larry.

Fig. 3: Tropical cyclone model intensities for Hurricane Larry.

Fig. 4: The North Atlantic sea surface temperatures.

Discussion: Larry may rival Ida for strongest tropical cyclone of the season (so far) although with an entirely different track. Fortunately, Larry is well out to sea as the hurricane tracks west and then west-northwest while steadily intensifying to a major hurricane by tomorrow. The latest NOAA/NHC 5-day forecast track takes Larry to the west-central North Atlantic subtropics in 5 days (Fig. 1). Tropical cyclone models are in good agreement although their 5-day forecast location is slightly west of the NOAA/NHC position (Fig. 2). Tropical cyclone models-intensity forecasts are generally in good agreement on Larry reaching category-3 major hurricane status with 3 models indicating a potential category-4/category-5 major hurricane later this weekend (Fig. 3).  

The concern is in the day 6-9 timeframe. If Larry becomes a major hurricane which (now) seems certain, the release of warm air into the surrounding environment by the attendant convection of the tropical cyclone can allow the subtropical ridge steering the tropical cyclone to linger. Forecast models are indicating an upper trough will boot Larry north and northeastward mid-to-late next week keeping this system away from the East Coast. However, any delay in that upper trough would allow Larry to edge closer to the East Coast later next week.

Also of interest…Larry is forecast to intensify to a major hurricane over 82-83F water this weekend (Fig. 4). The waters are 84-85F after the NOAA/CPC 5-day forecast track implying definite potential for strengthening to a category-4 hurricane.

CLOSE monitoring is required!