209
WTNT44 KNHC 280856
TCDAT4
TROPICAL DEPRESSION NINE DISCUSSION NUMBER 7
NWS NATIONAL HURRICANE CENTER MIAMI FL AL092025
500 AM EDT SUN SEP 28 2025
THE DEPRESSION HAS BEEN SLOWLY BECOMING MORE ORGANIZED OVERNIGHT.
THE MINIMUM CENTRAL PRESSURE HAS FALLEN TO 1003 MB, AND SATELLITE
IMAGES ARE INDICATING THAT A TIGHTER CIRCULATION HAS FORMED ALONG
WITH INCREASING DEEP CONVECTION. THE INITIAL INTENSITY IS HELD AT
30 KT PER THE LATEST AIRCRAFT FLIGHT-LEVEL WINDS, BUT THIS SYSTEM
WILL PROBABLY BECOME A TROPICAL STORM SOON.
THE INITIAL MOTION IS A BIT FASTER TO THE NORTH-NORTHWEST, OR 345/6
KT. THIS GENERAL MOTION WITH A TURN TOWARDS THE NORTH IS
ANTICIPATED DURING THE NEXT COUPLE OF DAYS WHILE THE SYSTEM MOVES
BETWEEN AN UPPER TROUGH OVER THE SOUTHEASTERN UNITED STATES AND THE
SUBTROPICAL RIDGE. BEYOND THAT TIME, MODELS ARE GENERALLY FASTER
AND MORE OFFSHORE OF THE UNITED STATES WITH THE EVENTUAL TRACK OF
THE TROPICAL CYCLONE, FOLLOWING THE TREND OF THE PAST FEW CYCLES,
DUE TO IT MISSING THE UPPER TROUGH AND EVENTUALLY FOLLOWING
HURRICANE HUMBERTO MORE OUT TO SEA. WHILE IT IS TOO EARLY TO FEEL
EXTREMELY CONFIDENT, ALMOST ALL OF THE RELIABLE ENSEMBLES NOW KEEP
THE SYSTEM OFFSHORE OF THE SOUTHEASTERN UNITED STATES, THOUGH SOME
IMPACTS ARE STILL ANTICIPATED. THE LATEST NHC FORECAST IS SHIFTED
TO THE SOUTH AND EAST, BUT IS NOT NEARLY AS FAR TO THE SOUTHEAST AS
THE LATEST CONSENSUS MODELS DUE TO CONTINUITY CONSTRAINTS.
NOW THAT A BETTER-DEFINED CORE HAS FORMED, GRADUAL INTENSIFICATION
IS ANTICIPATED FOR THE NEXT COUPLE OF DAYS WHILE THE SYSTEM REMAINS
IN A WARM WATER BUT MODERATE SHEAR ENVIRONMENT. THE INTENSITY
FORECAST IS SIMILAR TO THE PREVIOUS ONE THROUGH THE FIRST COUPLE
DAYS OF THE FORECAST. AFTERWARDS, THE INTENSITY FORECAST IS
SLIGHTLY RAISED AS THE SYSTEM COULD FIND ITSELF IN A LOWER SHEAR
ENVIRONMENT WHILE STILL OVER WARM WATERS. BY THE END OF THE
FORECAST, INTERACTION WITH A FRONTAL BOUNDARY IS LIKELY TO CAUSE
SOME WEAKENING, ALONG WITH EXTRATROPICAL TRANSITION. THIS IS A LOW
CONFIDENCE FORECAST AT LONG RANGE GIVEN THE RECENT LARGE TRACK
CHANGES.
KEY MESSAGES:
1. THE DEPRESSION IS EXPECTED TO STRENGTHEN AND BRING TROPICAL STORM
CONDITIONS TO PORTIONS OF THE CENTRAL AND NORTHWESTERN BAHAMAS
THROUGH TONIGHT. TROPICAL STORM CONDITIONS ARE ALSO POSSIBLE
ALONG PORTIONS OF THE EAST COAST OF CENTRAL FLORIDA BEGINNING
MONDAY, WHERE A TROPICAL STORM WATCH IS IN EFFECT.
2. RAINFALL ASSOCIATED WITH TROPICAL DEPRESSION NINE WILL CONTINUE
TO IMPACT EASTERN CUBA AND THE BAHAMAS THROUGH TUESDAY, WHICH WILL
LIKELY PRODUCE FLASH AND URBAN FLOODING. MUDSLIDES ARE POSSIBLE IN
THE HIGHER TERRAIN. HEAVY RAINFALL ACROSS THE COASTAL CAROLINAS
COULD CAUSE FLASH, URBAN, AND RIVER FLOODING INTO WEDNESDAY
MORNING.
3. THERE IS STILL A RISK OF HEAVY RAINFALL, WIND AND HIGH SURF
IMPACTS FOR THE SOUTHEAST U.S. COAST EVEN IF THE CENTER
REMAINS OFFSHORE. RESIDENTS SHOULD CLOSELY MONITOR THE LATEST
FORECAST UPDATES AND ENSURE THAT THEY HAVE THEIR HURRICANE PLAN IN
PLACE.
FORECAST POSITIONS AND MAX WINDS
INIT 28/0900Z 23.0N 77.2W 30 KT 35 MPH
12H 28/1800Z 24.1N 77.4W 40 KT 45 MPH
24H 29/0600Z 25.7N 77.6W 50 KT 60 MPH
36H 29/1800Z 27.4N 77.8W 60 KT 70 MPH
48H 30/0600Z 28.8N 77.8W 65 KT 75 MPH
60H 30/1800Z 29.5N 77.4W 70 KT 80 MPH
72H 01/0600Z 29.9N 75.5W 70 KT 80 MPH
96H 02/0600Z 30.6N 72.1W 75 KT 85 MPH
120H 03/0600Z 31.7N 66.4W 65 KT 75 MPH...POST-TROP/EXTRATROP
FORECASTER BLAKE
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