Beneficial Rainfall Ahead for Southeast Brazil
08/26/2019, 2:11 pm EDTSlow Turning Dorian Over Florida Causes Widespread Extreme Rainfall Episode
08/30/2019, 5:13 am EDTHighlight: Dorian may become a major hurricane; targets Florida.
Fig. 1: Satellite view of the North Atlantic basin.
Discussion: Tropical Storm Dorian is located at 16.8N/63.9W or about 85 miles southeast of St. Croix. Maximum wind is 60 mph with central pressure 1003 MB. Dorian is moving northwest at 13 mph. Tropical Storm Erin is located at 32.5N/72.4W or about 265 miles southeast of Cape Hatteras, NC. Erin has top wind 40 mph and is moving north-northwest at 6 mph.
Tropical Storm Erin will drift north and north-northeast today/tonight moving east of New England tomorrow. Erin’s attendant rainfall merges with a New England cold front causing a flash flood risk for eastern New England tonight.
All eyes are on Dorian. The forecast track has been adjusted well east as Dorian crosses Puerto Rico today. Dorian should re-emerge north of Puerto Rico relatively unscathed in intensity due to the limited high terrain of Puerto Rico (versus Hispaniola as previously forecast).
Dorian may slow on approach to Puerto Rico today, lose some intensity tonight crossing the island then re-emerge north of Puerto Rico reaching hurricane strength in 2 days. Dorian turns more west-northwest due to steering guidance of a strengthening Bermuda High on the weekend. Tropical cyclone models indicate Dorian could become a major hurricane in the day 4 to 5 period while east of Florida.
The projected landfall varies widely with the ECMWF on the central Florida coast while tropical cyclone model tracks are farther north toward Jacksonville.
Additionally, once inland the trend of models is away from the northeast Gulf of Mexico possibility as indicated yesterday and more toward stalling inland over northern Florida before turning north and northeast into the Carolinas. A massive amount of rain will be produced by this storm. However, forecast confidence is below average beyond day 3.
Elsewhere the ECMWF indicates 2 more potential tropical issues in the outer tropical North Atlantic in the 6-10 day period.
Fig. 2: The NOAA/NHC 5-day forecast track for Tropical Storm Dorian.
Fig. 3-4: Tropical cyclone models track and intensity forecast for Dorian.
Fig. 5: The extended-range tropical cyclone model tracks for Dorian and Erin.