000
AGXX40 KNHC 291758
MIMATS

MARINE WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
100 PM EST SUN OCT 29 2006

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

UPPER LEVELS...
MIDDLE AND UPPER LEVEL ANTICYCLONE CENTERED NEAR 25N58W WITH A 
RIDGE ACROSS THE GREATER ANTILLES TO SOUTHERN MEXICO.  WEAKENING 
MIDDLE LATITUDE TROUGH IS NORTH OF 25N OVER THE ATLANTIC W OF 
75W ACROSS FLORIDA AND TO 90W OVER THE GULF OF MEXICO.  THE 
ANTICYCLONE WILL WEAKEN WITH A RIDGE ALONG 22N ACROSS THE ENTIRE 
AREA BY TUESDAY NIGHT AND ONLY A WEAK TROUGH OVER THE ATLANTIC 
ALONG 70W NORTH OF 23N.  THE RIDGE WILL DRIFT SLIGHTLY SOUTH W 
OF 80W AS THE MIDDLE LATITUDE WESTERLIES EXTEND FURTHER SOUTH TO 
NEAR 23N OVER THE GULF OF MEXICO.  BY FRIDAY A BROAD MIDDLE 
LATITUDE TROUGH WILL COVER THE ATLANTIC AND GULF OF MEXICO NORTH 
OF 23N WITH AN AXIS NEAR FLORIDA.  NO SHORTWAVES ARE EXPECTED IN 
THE AREA MOVING THROUGH THE BROAD TROUGH.

SURFACE...
THE MAIN FEATURE IS THE COLD FRONT AND TROPICAL WAVE ALONG 73W 
AND THEIR INTERACTION IN THE NEXT FEW DAYS.  THE FRONTAL TROUGH 
IS EXPECTED TO BECOME STATIONARY AND MAINTAIN OR EVEN SLIGHTLY 
INCREASE IN INTENSITY WITH NORTHEAST TO EAST WINDS NORTH OF THE 
TROUGH IN THE 20 TO OCCASIONALLY 25 KT RANGE.  THE GFS COMPUTER 
MODEL INDICATES A CELLULAR NATURE TO THE WIND FIELD WHICH IS A 
SIGN THAT CONVECTION WILL PLAY AN IMPORTANT ROLE IN HOW THE 
TROUGH DEVELOPS. WILL BASICALLY GO WITH THE GFS BUT LEAVE OUT 
THE EXTREME VALUES NEAR THE CELLULAR CENTERS.  ONCE THE TROUGH 
BEGINS TO DEVELOP ON TUESDAY THE PRESSURE GRADIENT ASSOCIATED 
WITH THE TROPICAL WAVE WILL WEAKEN WITH WINDS IN THE CARIBBEAN 
BECOMING LESS THAN NORMAL.

NEXT COLD FRONT ASSOCIATED WITH THE BROAD MIDDLE LATITUDE TROUGH 
WILL MOVE OFF THE NORTH GULF COAST EARLY THURSDAY AND BY FRIDAY 
EXTEND FROM NEAR 31N70W TO THE BAY OF CAMPECHE.  A FAIRLY STRONG 
HIGH IS NORTH OF THE FRONT AND WINDS WILL BE IN THE 20 TO 25 KT 
RANGE BEHIND THE FRONT.

WARNINGS...

ATLC...
NONE.

CARIBBEAN...
NONE.

GULF OF MEXICO...
NONE.

FORECASTER LL