000
AGXX40 KNHC 290535
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
130 AM EST MON DEC 29 2003

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

COMPUTER MODELS DOING A GOOD JOB ON HANDLING THE DEVELOPMENT OF 
THE GALE CENTER OVER THE MID ATLC. UPPER PATTERN COINCIDES WELL 
WITH LATEST WATER VAPOR IMAGERY WITH ATLC TROUGH EXTENDING S OF 
20N.  OPEN UPPER RIDGE NOW ALONG EASTERN SEABOARD SHIFTING 
SLOWLY E..AND NEXT BIG TROUGH DROPPING INTO THE PLAINS AND 
EXTENDING S OVER MEXICO. 

STRONG NLY WINDS HIGHLITE THE ATLC PICTURE DAY 1 E OF 70W WITH A 
TIGHT PRESSURE GRADIENT BETWEEN THE DEPARTING GALE CENTER AND 
THE LARGE SURFACE RIDGE OVER THE SW ATLC. STRONG NE WINDS SWEEP 
INTO ALL OF THE CARIBBEAN AS WELL. 

THE NEXT COLD FRONT OVER THE W GULF WILL MOVE TO 30N90W 20N96W 
DAY 1 WITH 20 TO 30 KT WINDS BEHIND IT. POSSIBLE GUSTS TO GALE 
ALONG THE MEXICAN COAST S OF 25N. SLY WINDS OF 20 TO 25 KT AHEAD 
OF THE FRONT N OF 28N AS FRONT BUTTS UP AGAINST ATLC RIDGE.

UPPER FEATURES OVER ATLC CHANGE LITTLE DAY 2 DUE TO LARGE 
AMPLITUDE. NO SO WITH PLAINS TROUGH WHICH UNDERGOES RAPID 
DECREASE IN AMPLITUDE AND MOVES INTO MS VALLEY WITH UPPER 
PATTERN BECOMING MORE ZONAL.

STRONG NLY WINDS SHIFT SLOWLY E OF 65W DAY 2 BUT CONTINUE OVER 
CARIBBEAN. GULF FRONT LOOSES STEAM OVER EASTERN PORTION AS 
AIRMASS FOLLOWING FRONT IS RELATIVELY MILD.

OUTLOOK PERIOD...
 
UPPER TROUGH OVER ATLC CONTINUES SLOW MOVEMENT E WHILE UPPER 
RIDGE STRENGTHENS OVER OUR REGION S OF 30N. RIDGE AND ZONAL FLOW 
TO NORTH WILL AFFECTIVELY KEEP SYSTEMS IN THE WESTERLIES N OF 
THE AREA.

WINDS OVER ATLC DECREASE DAY 3 BUT REMAIN ON STRONG SIDE OVER 
CARIBBEAN. SURFACE RIDGE ELONGATES E/W IN RESPONSE TO ZONAL FLOW.

LITTLE CHANGE DAY 4 TO UPPER PATTERN WITH RIDGE OVER REGION 
BECOMING SLIGHTLY STRONGER. WESTERLIES REMAIN N OF AREA. SURFACE 
RIDGE FORECAST TO STRENGTHEN SLIGHTLY IN RESPONSE TO STRONGER 
UPPER RIDGE. THIS WILL CONTINUE STRONG ELY WINDS OVER CARIBBEAN.

UPPER RIDGE REMAINS STRONG OVER REGION AND PHASES IN WITH 
APPROACHING OPEN RIDGE IN WESTERLIES. SURFACE RIDGE COVERS AREA 
N OF 20N ALTHOUGH SLIGHTLY WEAKER DAY 5..BUT STILL STRONG ENOUGH 
TO KEEP WINDS OF 25 KT OVER ALL OF CARIBBEAN EXCEPT EXTREME NW 
PORTION. 

NEXT SHORT WAVE DROPS INTO SOUTHERN ROCKIES AND WILL MOVE 
RAPIDLY E IN THE STRONG ZONAL FLOW. THIS WILL LOWER PRESSURES 
OVER THE SOUTHERN PLAINS AND INCREASE THE RETURN FLOW OVER THE 
NW GULF BEGINNING LATE DAY 5.

WARNINGS...
GALE CONDITION JUST E OF 55W AND N OF 29N ASSOCIATED WITH LOW 
CENTER MOVING NNE.

FORECASTER RRG