By PDC’s Senior Weather
Specialist Glenn James
The Pacific Disaster Center’s (PDC Global) Wednesday, September 13, 2023, Tropical Cyclone Activity Report…for the Atlantic Ocean, the Caribbean Sea, and the Gulf of Mexico
CURRENT TROPICAL CYCLONES:
Tropical Cyclone 13L (Lee)…is located about 325 miles southwest of Bermuda
Tropical Cyclone 14L (Margot)…is located about 770 miles west of the Azores
Tropical Cyclone 13L (Lee)
TROPICAL STORM CONDITIONS EXPECTED TO BEGIN ON BERMUDA IN A FEW HOURS
According to the NHC advisory number 35A…
Lee is moving toward the north near 9 mph (15 km/h). A generally northward motion and an increase in forward speed are expected through Friday. On the forecast track, the center of Lee will pass west of Bermuda today and tonight and then approach the coast of New England and Atlantic Canada Friday and Saturday.
Data from Air Force Reserve and NOAA Hurricane Hunter aircraft indicate that maximum sustained winds are now near 100 mph (155 km/h) with higher gusts. Additional weakening is forecast, but Lee is expected to remain a large and dangerous hurricane for the next couple of days.
Hurricane-force winds extend outward up to 115 miles (185 km) from the center and tropical-storm-force winds extend outward up to 265 miles (425 km). Saildrone 1065 recently measured a sustained wind of 73 mph (117 km/h), a gust to 94 mph (152 km/h), and a significant wave height of 44 feet (13.3 meters) while located about 65 miles (100 km) northeast of Lee’s center.
HAZARDS AFFECTING LAND
WIND: Tropical storm conditions are expected in Bermuda starting early Thursday. Hurricane conditions are possible in portions of Down East Maine and in the Hurricane Watch area in Atlantic Canada on Saturday. Tropical storm conditions are possible in portions of coastal New England and Atlantic Canada in the Tropical Storm Watch area beginning Friday night.
STORM SURGE: The combination of storm surge and tide will cause normally dry areas near the coast to be flooded by rising waters moving inland from the shoreline. The water could reach the following heights above ground somewhere in the indicated areas if the peak surge occurs at the time of high tide…
Chatham, MA to Sagamore Beach, MA…2-4 ft
Cape Cod Bay…2-4 ft
Sagamore Beach, MA to Border of US/Canada…1-3 ft
Boston Harbor…1-3 ft
Flushing, NY to Chatham, MA…1-3 ft
Montauk Point, NY to Flushing, NY…1-3 ft
Long Island Sound…1-3 ft
Martha’s Vineyard…1-3 ft
Rockaway Inlet, NY to Montauk Point, NY…1-2 ft
The deepest water will occur along the immediate coast where the
surge will be accompanied by large and destructive waves.
Surge-related flooding depends on the relative timing of the surge
and the tidal cycle, and can vary greatly over short distances.
A dangerous storm surge could produce coastal flooding within the wind watch areas in Atlantic Canada in areas of onshore winds. Near the coast, the surge will be accompanied by large and destructive waves.
SURF: Swells generated by Lee are affecting portions of the Lesser Antilles, the British and U.S. Virgin Islands, Puerto Rico, Hispaniola, the Turks and Caicos Islands, the Bahamas, Bermuda, the east coast of the United States and are beginning to reach Atlantic Canada. These swells are likely to cause life-threatening surf and rip current conditions.
RAIN: Outer rain bands from Lee could produce rainfall amounts of 1 to 2 inches, or 25 to 50 millimeters, across Bermuda Thursday into early Friday.
From Friday night through Saturday night, Lee is expected to produce
rainfall amounts of 1 to 4 inches, or 25 to 100 millimeters, across
portions of eastern New England into portions of New Brunswick and Nova Scotia. This could produce localized urban and small stream flooding.
Tropical Cyclone 14L (Margot)
MARGOT TO MEANDER OVER THE NORTH ATLANTIC
According to the NHC advisory number 27…
Margot is moving toward the north near 7 mph (11 km/h), and this motion is expected to continue with a gradual decrease in forward speed through Thursday. Margot is then likely to meander within weak steering currents through this weekend.
Maximum sustained winds have decreased to near 85 mph (140 km/h) with higher gusts. Steady weakening is forecast over the next few days.
Hurricane-force winds extend outward up to 70 miles (110 km) from the center and tropical-storm-force winds extend outward up to 230 miles (370 km).
HAZARDS AFFECTING LAND
SURF: Swells generated by Margot will continue to affect the Azores for the next several days. These swells are likely to cause life-threatening surf and rip current conditions.
>>> Eastern and Central Tropical Atlantic…
Showers and thunderstorms associated with a broad area of low pressure located several hundred miles west-southwest of the Cabo Verde Islands continue to become better organized this evening.
Environmental conditions are favorable for further development of this system, and a tropical depression is likely to form by this weekend as the low moves west-northwestward to northwestward at 10 to 15 mph across the central tropical Atlantic.
* Formation chance through 48 hours…high…80 percent
* Formation chance through 7 days…high…90 percent