… TROPICAL STORM ISAAC APPROACHES THE LESSER ANTILLES…
DATE ISSUED: Tuesday, September 11, 2018 TIME ISSUED: 11:00 AM
Location: Lat. 14.6N Lon. 49.7W
About: 920 miles ESE of St. Maarten
Maximum sustained winds: 70 mph ….110 KM/H
Present Movement: W…270 degrees at 16 mph…26 KM/H
Minimum Central Pressure: 996 mb….29.42 inches
DISCUSSION AND 24-HOUR OUTLOOK
AT 11:00AM..THE CENTER OF TROPICAL STORM ISAAC WAS LOCATED NEAR LATITUDE 14.6 NORTH…LONGITUDE 49.7 WEST OR ABOUT 920 MILES EAST SOUTHEAST OF ST. MAARTEN.
ISAAC IS MOVING TOWARD THE WEST, NEAR 16 MPH (26 KM/H). THIS MOTION IS EXPECTED TO CONTINUE THROUGH THE END OF THE WEEK.
ON THIS FORECAST TRACK ISAAC IS EXPECTED TO MOVE ACROSS THE LESSER ANTILLES AND INTO THE CARIBBEAN SEA THURSDAY. BASED ON THE 11AM POSITION AND MOVEMENT, THE CENTER OF ISAAC WOULD BE AT ITS CLOSEST TO ST. MAARTEN AT APPROXIMATELY 185 MILES SOUTHWEST EARLY FRIDAY MORNING.
MAXIMUM SUSTAINED WINDS REMAIN NEAR 70 MPH…110 KM/H.WITH HIGHER GUSTS. ISAAC IS EXPECTED TO BE NEAR HURRICANE STRENGTH WHEN IT MOVES THROUGH THE CENTRAL LESSER ANTILLES THURSDAY WITH SOME WEAKENING FORECAST AFTERWARDS. TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105 MILES FROM THE CENTER.
THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 996 MB…29.42 INCHES.
Track: Most models are in agreement that the centre of Isaac will move somewhere between Guadeloupe and Martinique.
Landfall: The models vary with the time and place of landfall at the current time. That will depend on whether the forward speed increases or decreases before the arrival. At the moment it is likely to be sometime on Thursday.
Intensity: Intensity continues to be a challenge. However, it is expected to be near hurricane strength when it reaches the islands.
Based on the above information, the expected impacts on St. Maarten are as follows:
Seas: Sea conditions will begin to deteriorate by Wednesday with waves peaking near 8ft and will further deteriorate Thursday through Friday up to 10 feet or more.
Winds: Winds are expected to increase on Wednesday up 15 kts (20mph) and from Thursday through Friday up to 25kts (30mph) with higher gusts.
Rainfall: Models are indicating totals of less than 2 inches over St. Maarten (2 inches). Shower activity associated with Isaac will begin early Wednesday with an outer band from the system. Rainfall is expected to decrease on Thursday and then increased activity through the weekend.
Because Isaac is such a small system there are a lot of uncertainties with the forecast. It is likely that as the system draws closer to the islands the track and intensity may change. Therefore, it is important to keep updated and alert.
A Watch will be issued for St. Maarten if necessary.
THE METEOROLOGICAL DEPARTMENT WILL CONTINUE TO MONITOR HURRICANE ISAAC AND ISSUE
SPECIAL WEATHER BULLETINS WHEN NESCESSARY.
Source: The Daily Herald https://www.thedailyherald.sx/islands/80513-local-tropical-weather-update