TROPICAL STORM MATTHEW DISCUSSION NUMBER   7
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL   AL152010
1100 PM EDT FRI SEP 24 2010

SURFACE OBSERVATIONS AND DATA FROM AN AIR FORCE RESERVE HURRICANE
HUNTER AIRCRAFT INDICATE THAT MATTHEW HAS NOT WEAKENED MUCH THIS
EVENING.  PUERTO LIMPERA IN EASTERN HONDURAS REPORTED A 10-MINUTE
WIND OF 38-40 KNOTS AT 2300 AND 0000 UTC...AND THE AIRCRAFT FOUND A
850-MB FLIGHT LEVEL WIND MAXIMUM OF 58 KT AND A PEAK SFMR WINDS OF
51 KT OFFSHORE OF THE COAST OF HONDURAS JUST PRIOR TO 0000 UTC. 
BASED ON THESE DATA...AND THE FACT THAT THE CYCLONE HAS BEEN OVER
LAND FOR ANOTHER 3 TO 4 HOURS...THE INITIAL INTENSITY IS SET TO 45
KT.  WEAKENING IS EXPECTED OVERNIGHT WHILE THE CENTER REMAINS OVER
LAND...BUT LITTLE CHANGE IN INTENSITY IS EXPECTED FROM 12 TO 24
HOURS AS THE CENTER IS FORECAST TO EMERGE INTO THE GULF OF HONDURAS
BEFORE MOVING INTO BELIZE.  BEYOND 24 HOURS...GRADUAL WEAKENING IS
FORECAST AND THE LOW-LEVEL CENTER IS EXPECTED TO DISSIPATE OVER
GUATEMALA OR EASTERN MEXICO IN 3 OR 4 DAYS.  THE NHC FORECAST IS
CLOSE TO THE DECAY SHIPS AND LGEM THROUGH THE PERIOD. 

SURFACE DATA...SATELLITE FIXES AND RADAR DATA FROM THE AIRCRAFT
SUGGEST THAT THE CENTER OF MATTHEW IS A LITTLE TO THE NORTH OF THE
PREVIOUS TRACK...AND THE INITIAL MOTION ESTIMATE IS 285/13.
OVERALL...THE TRACK FORECAST REASONING REMAINS UNCHANGED...AS A
STRONG MID-LEVEL RIDGE OVER THE GULF OF MEXICO WILL GENERALLY STEER
MATTHEW WEST-NORTHWESTWARD FOR THE NEXT 36 HOURS OR SO.  BY THE
TIME MATTHEW MOVES INTO GUATEMALA AND MEXICO...THE STEERING FLOW
WILL WEAKEN AS THE RIDGE BREAKS DOWN AND A SLOWER MOTION TOWARD THE
WEST-NORTHWEST IS EXPECTED UNTIL DISSIPATION. THE NEW NHC FORECAST
IS SHIFTED NORTH OF THE PREVIOUS ONE...BUT STILL LIES A LITTLE
SOUTH OF THE CENTER OF THE GUIDANCE SUITE. THE FORWARD SPEED WAS
TRENDED TOWARD THE TVCN MULTI-MODEL CONSENSUS. 

A LARGE AREA OF CLOUD TOPS COLDER THAN -80C HAVE RECENTLY DEVELOPED
NEAR AND SOUTH OF THE CENTER OVER PORTIONS OF HONDURAS AND
NICARAGUA...LIKELY PRODUCING EXTREMELY HEAVY RAINFALL IN THESE
AREAS. THE HEAVY RAIN THREAT WILL PERSIST FOR SEVERAL DAYS...EVEN
AFTER MATTHEW WEAKENS.  

FOR THE PAST FEW DAYS GLOBAL MODELS HAVE BEEN CONSISTENTLY DEPICTING
A TROPICAL CYCLONE IN THE NORTHWESTERN CARIBBEAN SEA TOWARD THE
MIDDLE OF NEXT WEEK. THE MOST RECENT RUNS INDICATE THAT ANY
DEVELOPMENT THERE WOULD LIKELY NOT HAVE CONTINUITY WITH MATTHEW...
BUT RATHER REPRESENT THE FORMATION OF A NEW TROPICAL CYCLONE.
 
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