000
AGXX40 KNHC 300610
MIMATS

MARINE WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
130 AM EST SUN DEC 30 2007

MARINE WEATHER DISCUSSION FOR GULF OF MEXICO...CARIBBEAN SEA
AND SOUTHWEST NORTH ATLC S OF 31N W OF 55W.

INTERESTING SITUATION TONIGHT OVER ERN ATLC WITH CLOSED LOW AT 
MID LEVELS NEAR 27N37W AND STRONG SHORTWAVE IN WESTERLIES 
PASSING BY TO N. WILL SHORTWAVE HAVE ANY INFLUENCE ON LOW?? GFS 
SAYS NO..NOT DIRECTLY BUT IMPLIES INDIRECT INFLUENCE WITH MID 
LEVEL RIDGE BUILDING BEHIND TROUGH AS IT PASSES WILL PUSH LOW 
BACK TO SW. STRONG RIDGE CENTER HOLDS FIRM NEAR 22N72W. NEXT 
STRONG SHORTWAVE IN WESTERLIES DROPPING INTO SRN PLAINS TONIGHT. 
ON THE SURFACE GALE CENTER BENEATH MID LEVEL LOW AT 27N37W 
THEREFORE NO BAROCLINICITY..BUT LATEST SATELLITE PICTURES SHOW 
CONVECTION BEGINNING TO WRAP AROUND CENTER..THUS POSSIBLE 
SUBTROPICAL DEVELOPMENT TAKING PLACE. LARGE MID ATLC RIDGE 
MAINTAINING 20 TO 25 KT ELY WINDS BETWEEN 50W AND 80W S OF 23N. 
GULF FRONT NEARLY STATIONARY WITH WINDS 10 TO 15 KT TONIGHT. 

LATER DAY 1 MID LEVEL LOW OVER E CENTRAL ATLC DRIFTING SW TO 
NEAR 25N37W. STRONG SHORTWAVE MOVES TO MID MS VALLEY. ON THE 
SURFACE LATER DAY 1 GFS MODEL DOES NOT SHOW ANY FURTHER 
DEVELOPMENT WITH ATLC LOW BUT GRADIENT BETWEEN LOW AND RIDGE TO 
N WILL MAINTAIN 25 TO 35 KT WINDS. NEW PUSH OF NW WINDS OVER NW 
GULF TO 20 KT AS SHORTWAVE PASSES BY BUT ATLC RIDGE NOSES INTO 
TO GULF WILL IMPEDE MOVEMENT. CARIB WINDS MOSTLY 20 TO 25 KT E 
OF 80W. 

FOR DAY 2 MID LEVEL LOW OVER ATLC MOVES SW TO 24N40W WHILE MID 
LEVEL RIDGE SPREADS ENE TO 30N45W. STRONG WESTERLIES LOWERING 
MID LEVEL HEIGHTS OVER N GULF AS NEXT SHORTWAVE DROPS INTO 
CENTRAL PLAINS. ON THE SURFACE DAY 2 GALE CONDITIONS CONTINUE 
WITH ATLC LOW WITH SAME SITUATION. GULF FRONT MOVES E BUT 
WEAKENS CONSIDERBLY. NO CHANGE IN CARIB.

OUTLOOK PERIOD...

FOR DAY 3 MID LEVEL ATLC LOW WEAKENS AS IT DRIFTS SW TO NEAR 
18N43W. STRONG SHORTWAVE IN WESTERLIES GETS SECOND SURGE OF COLD 
AIR OVER MIDWEST AND DIVES SE. ON THE SURFACE DAY 3 SURGE OF 
POLAR AIR FOLLOWING STRONG SHORTWAVE DIVES INTO SRN PLAINS AND 
ACROSS GULF WITH GALE CONDITIONS. FRONT PUSHES RAPIDLY EWD TO 
SRN FL. GRADIENT WEAKENS OVER CARIB AND WINDS DECREASE SOME. 

FOR DAY 4 STRONG SHORTWAVE BARRELS OFF DELMARVA AS STRONG MID 
LEVEL RIDGE BUILDS RAPIDLY NWD OVER PLAINS. WEAKENED MID LEVEL 
LOW OVER TRPL ATLC NEAR 15N42W. ON THE SURFACE DAY 4 POLAR 
AIRMASS LOOSES LITTLE STRENGTH AS A 1043 MB HIGH MOVES E TO 
TX/LA BORDER. GALE CONDITIONS SPREAD OVER ATLC W OF COLD FRONT 
PROBABLY N OF 28N WITH BEST ISALLABARIC CHANGE. ATLC HIGH 1027 
MB OVER ERN ATLC STRENGTHENS ELY TRADES E OF 50W. STRONG N WINDS 
INVADE NW CARIB BEHIND FRONT.

FOR DAY 5 STRONG SHORTWAVE TROUGH LOOSES LITTLE AMPLITUDE AS IT 
CONTINUES EWD TO 60W. MID LEVEL RIDGING OVER PLAINS WASHES OUT 
AS IT GETS CAUGHT UP IN STRONG ZONAL FLOW. OLD CLOSED MID LEVEL 
LOW OVER TRPL ATLC STATIONARY AT 18N42W. ON THE SURFACE DAY 5 
STRONG POLAR HIGH MOVES EWD TOWARD CAR COAST WITH 20 TO 30 KT 
WINDS W OF COLD FRONT 31N55W 20N70W.  ALL CARIB NE 20 TO 25 KT. 
E ATLC RIDGE WEAKENS WITH ELY TRADES TO 20 KT E OF 45W.

WARNINGS...
ATLANTIC...
GALE WRNG WITH LOW CENTER NEAR 27N37W...PSBL SUBTRPC DVLPMNT.

CARIBBEAN...
NONE. 

GULF OF MEXICO...
GALE DEVELOPING BEHIND COLD FRONT DAY 3.

FORECASTER RRG