Tropical Depression Ingrid Advisory 18

TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
5:30 PM EDT SUN SEP 16 2007
FOR THE NORTH ATLANTIC, CARIBBEAN SEA AND THE GULF OF MEXICO,
THE NATIONAL HURRICANE CENTER IS ISSUING ADVISORIES ON TROPICAL
DEPRESSION INGRID, CENTERED ABOUT 210 MILES EAST OF THE LEEWARD
ISLANDS.
DISORGANIZED CLOUDINESS AND A FEW THUNDERSTORMS OVER THE CENTRAL
CARIBBEAN SEA ARE ASSOCIATED WITH A TROPICAL WAVE AND AN
UPPER-LEVEL TROUGH. UPPER-LEVEL WINDS ARE CURRENTLY UNFAVORABLE
FOR DEVELOPMENT OF THIS SYSTEM, BUT THEY COULD BECOME A LITTLE
MORE FAVORABLE FOR SLOW DEVELOPMENT IN A COUPLE OF DAYS AS THE
SYSTEM MOVES WESTWARD AT 10 TO 15 MPH.
A TROPICAL WAVE LOCATED ABOUT HALFWAY BETWEEN AFRICA AND THE LESSER
ANTILLES IS PRODUCING A LARGE BUT DISORGANIZED AREA OF CLOUDINESS
AND THUNDERSTORMS. DEVELOPMENT OF THIS SYSTEM, IF ANY, IS
EXPECTED TO BE SLOW TO OCCUR as it MOVES WESTWARD AT 10 TO 15 MPH.
ELSEWHERE, TROPICAL CYCLONE FORMATION IS NOT EXPECTED DURING THE
NEXT 48 HOURS.
BULLETIN
TROPICAL DEPRESSION INGRID ADVISORY NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082007
5:00 PM AST SUN SEP 16 2007
, DISORGANIZED INGRID MOVING WEST-NORTHWESTWARD WITH LITTLE CHANGE
IN STRENGTH,
INTERESTS IN THE NORTHERN LEEWARD ISLANDS SHOULD MONITOR THE
PROGRESS OF INGRID.
AT 5:00 PM AST, 21:00Z, THE CENTER OF TROPICAL DEPRESSION INGRID WAS
LOCATED NEAR LATITUDE 17.4 NORTH, LONGITUDE 58.6 WEST OR ABOUT 210
MILES, 340 KM, EAST OF THE LEEWARD ISLANDS.
THE DEPRESSION IS MOVING TOWARD THE WEST-NORTHWEST NEAR 10 MPH, AND
THIS GENERAL MOTION IS EXPECTED TO CONTINUE FOR THE NEXT 24 HOURS.
ON THE FORECAST TRACK, THE CENTER SHOULD PASS JUST TO THE
NORTHEAST AND NORTH OF THE NORTHERN LEEWARD ISLANDS. HOWEVER A
DEVIATION TO THE LEFT COULD BRING THE CENTER NEAR THOSE ISLANDS ON
MONDAY.
MAXIMUM SUSTAINED WINDS ARE NEAR 35 MPH, 55 KM/HR, WITH HIGHER
GUSTS. LITTLE CHANGE IN STRENGTH IS FORECAST DURING THE NEXT 24
HOURS.
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 milibars, 29.71 INCHES.
REPEATING THE 500 PM AST POSITION, 17.4 N, 58.6 W. MOVEMENT
TOWARD, WEST-NORTHWEST NEAR 10 MPH. MAXIMUM SUSTAINED WINDS, 35
MPH. MINIMUM CENTRAL PRESSURE, 1006 milibars.
THE NEXT ADVISORY WILL BE ISSUED BY THE NATIONAL HURRICANE CENTER AT
11:00 PM AST.
TROPICAL DEPRESSION INGRID DISCUSSION NUMBER 18
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL082007
5:00 PM EDT SUN SEP 16 2007
AFTER BECOMING A LITTLE BETTER ORGANIZED THIS MORNING, THE
SATELLITE PRESENTATION OF INGRID HAS AGAIN DETERIORATED. THE CLOUD
PATTERN HAS BECOME QUITE RAGGED, DEEP CONVECTION IS LIMITED, AND
THE LOW CLOUD LINES DEPICTING THE CIRCULATION HAVE BECOME
INDISTINCT. MOREOVER, A NUMBER OF ARC CLOUDS, IMPLYING LOW-LEVEL
DIVERGENCE, ARE SEEN EMANATING FROM THE WESTERN PORTION OF THE
SYSTEM. THE INTENSITY IS KEPT AT 30 KT IN ACCORDANCE WITH THE TAFB
DVORAK ESTIMATE. WESTERLY SHEAR IS FORECAST TO REMAIN RATHER
STRONG FOR THE NEXT DAY OR SO, WHICH MAKES SIGNIFICANT
INTENSIFICATION UNLIKELY IN THE SHORT TERM. INDEED IF THE CURRENT
DISORGANIZING TREND CONTINUES, INGRID WILL WEAKEN. HOWEVER SOME
OF THE GLOBAL MODELS FORECAST A SLIGHTLY MORE FAVORABLE UPPER-LEVEL
FLOW TO EVOLVE LATER IN THE FORECAST PERIOD. THEREFORE, IF INGRID
SURVIVES FOR THE NEXT COUPLE OF DAYS, it COULD BEGIN TO
RESTRENGTHEN IN 3-4 DAYS. THE OFFICIAL INTENSITY FORECAST ALLOWS
FOR THIS POSSIBILITY, AND IS SLIGHTLY BELOW THE LATEST LGEM AND
HWRF GUIDANCE AT THAT TIME FRAME. ALTERNATIVELY THE GFDL NOW
DISSIPATES THE CYCLONE WITHIN 36 HOURS.
THE LOW-LEVEL CENTER IS DIFFICULT TO FIND AND THERE IS A LOT OF
SPREAD IN LOCATION ESTIMATES THIS AFTERNOON. CONSEQUENTLY THE
INITIAL MOTION ESTIMATE IS A RATHER UNCERTAIN 285/9. THE STEERING
CURRENTS FOR INGRID ARE NOT WELL-DEFINED. THE LOW- TO MID-LEVEL
RIDGE TO THE NORTH OF THE CYCLONE IS LIKELY TO WEAKEN DURING THE
NEXT DAY OR TWO, WHICH WOULD BRING ABOUT A GRADUAL TURN TO THE
RIGHT. A MID-LEVEL TROUGH DROPPING INTO THE WEST-CENTRAL ATLANTIC
IN 3-4 DAYS MIGHT BE JUST A LITTLE TOO FAR EAST TO HAVE A DIRECT
INFLUENCE ON INGRID'S MOTION. THE OFFICIAL TRACK FORECAST SLOWS
THE FORWARD SPEED TO LESS THAN 5 KT LATER IN THE PERIOD, AND IS
NOT FAR FROM THE CONU DYNAMICAL MODEL CONSENSUS.
INTERESTS IN THE NORTHERN LEEWARD ISLANDS SHOULD MONITOR THE
PROGRESS OF INGRID SINCE it IS POSSIBLE FOR THE SYSTEM TO MOVE MORE
TO THE LEFT OF OUR FORECAST TRACK. A NOAA HURRICANE HUNTER PLANE
IS SCHEDULED TO FLY A RESEARCH MISSION INTO THE CYCLONE AROUND 0000
UTC AND HOPEFULLY WILL BE ABLE TO PROVIDE A POSITION AND INTENSITY
ESTIMATE.