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4 pm Advisory — Center of Fred Crossing the Dominican Republic

| August 11, 2021 @ 4:05 pm

SUMMARY OF 400 PM CDT INFORMATION:

LOCATION…18.9N 71.0W
ABOUT 75 MI…125 KM WNW OF SANTO DOMINGO DOMINICAN REPUBLIC
ABOUT 210 MI…335 KM SE OF GREAT INAGUA ISLAND
MAXIMUM SUSTAINED WINDS…40 MPH…65 KM/H
PRESENT MOVEMENT…WNW OR 290 DEGREES AT 15 MPH…24 KM/H
MINIMUM CENTRAL PRESSURE…1007 MB…29.74 INCHES

WATCHES & WARNINGS:

A Tropical Storm Warning is in effect for…
* Dominican Republic on the south coast from Punta Palenque eastward and on the north coast from the Dominican Republic/Haiti border eastward

A Tropical Storm Watch is in effect for…
* Haiti from the northern border with the Dominican Republic to Gonaives
* Turks and Caicos Islands
* Southeastern Bahamas
* The Cuban provinces of Ciego de Avila, Camaguey, Las Tunas, Holguin, Granma, Santiago de Cuba, and Guantanamo

FORECAST DISCUSSION:

During the past several hours, the center of Fred has moved inland over the Dominican Republic. The storm continues to produce an area of convection near and southeast of the center. However, the low-level circulation is losing some organization as it passes over mountainous terrain. There have been no observations near the center recently, so the initial intensity of 35 kt is based mainly on weakening from the previous over water intensity.

The initial motion is a somewhat uncertain 290/13. Some erratic motion is expected during the next 12 h or so as the center moves over the mountains of Hispaniola. After reaching the water, the cyclone is expected to move west-northwestward on the south side of the subtropical ridge through about 60 h. After that, a northwestward motion is expected through the end of the forecast period as Fred moves toward a weakness in the ridge. The track guidance becomes a bit divergent during this time, with the ECMWF, Canadian, and HWRF models showing a track near or over the Florida Peninsula, while the GFS, UKMET, and HMON models show the center passing south and west of the Florida Keys, followed by a more northward motion over the Gulf of Mexico. The new forecast track is between these extremes, and it has only minor adjustments from the previous NHC track.

Fred is expected to weaken to a depression over Hispaniola during the next 12 h. Once back over water, the cyclone is expected to be in a moderate westerly shear environment through at least 60 h. Due to that, and the uncertainty in how well organized the system will be after crossing Hispaniola, the intensity forecast shows only modest intensification during this time. After that time, the global models forecast that an upper-level trough over Florida will gradually move to the north, with a large upper-level anticyclone following near or to the southeast of Fred. How close this anticyclone gets to Fred will determine how much the shear decreases while the system is over the eastern Gulf of Mexico, and the global models are not in great agreement on this. The GFS and Canadian keep the high far enough to the east to expose Fred to southwesterly upper-level winds, while the UKMET and ECMWF move it closer to the storm. The intensity forecast will show a slightly faster rate of strengthening after 72 h to match the guidance and the previous forecast. However, there is lower than normal confidence in this part of the intensity forecast.

KEY MESSAGES:

1. Tropical storm conditions are ongoing across portions of the Dominican Republic. Tropical storm conditions are possible in northern Haiti and the southeastern Bahamas this evening, and in portions of Cuba by tonight.

2. Through early Thursday morning, heavy rainfall could lead to flash, urban, and small stream flooding, along with possible rapid river rises and potential mudslides in the Dominican Republic.

3. There is a risk of wind and rainfall impacts elsewhere in portions of Hispaniola, the Bahamas, and Cuba during the next few days, although the forecast is more uncertain than usual since Fred is forecast to interact with Hispaniola through tonight.

4. There is an increasing risk of wind and rainfall impacts in Florida beginning Friday night or early Saturday in the Keys and spreading northward through portions of the Peninsula and the Panhandle Saturday through Monday. Beginning Friday, heavy rainfall could lead to areal, urban, and small stream flooding, and possible rapid river rises across southern Florida. Interests throughout Florida should monitor Fred’s progress and check updates to the forecast.

Category: ALL POSTS, Tropical

About the Author ()

Scott Martin is an operational meteorologist, professional graphic artist, musician, husband, and father. Not only is Scott a member of the National Weather Association, but he is also the Central Alabama Chapter of the NWA president. Scott is also the co-founder of Racecast Weather, which provides forecasts for many racing series across the USA. He also supplies forecasts for the BassMaster Elite Series events including the BassMaster Classic.

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