000
AGXX40 KNHC 170458
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
130 AM MON JUL 17 2006

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

THE BATTLE CONTINUES TONIGHT OVER THE SW ATLC BETWEEN TWO LARGE 
UPPER RIDGE CENTERS AND TWO SHORTWAVE TROUGHS. THE RIDGES ARE 
CENTERED OVER THE SRN US AND OVER THE E CENTRAL ATLC NEAR 
36N42W. IN BETWEEN A PRESSURE WEAKNESS AT MID LEVELS INVITES 
SHORTWAVES FROM THE WESTERLIES AND FROM THE EASTERLIES. ON THE 
SURFACE TONIGHT WEAK TROPICAL WAVES WERE LOCATED NEAR 56W..77W 
AND 93W MOVING W 15 KT. THE ATLC RIDGE AXIS WAS FROM 31N57W TO 
THE FL STRAITS.

LATER DAY 1 WHILE ONE SHORTWAVE TROUGH EXITS THE WEAKNESS AREA 
ALONG 70W..ANOTHER ONE ALONG 60W IS MOVING NW FROM THE TROPICAL 
EASTERLIES. YET ANOTHER SHORTWAVE IN THE EASTERLIES IS LOCATED 
ALONG 37W MOVING W. ANOTHER SHORTWAVE IN THE EASTERLIES WAS 
LOCATED OVER THE WRN CARIB ALONG 82W. ON THE SURFACE DAY 1 THE 
ATLC RIDGE IS CONFINED E OF 80W WITH IT'S AXIS 31N60W TO 26N80W. 
CARIB WINDS REMAIN BRISK AT 20 TO 25 KT WHILE GULF WINDS REMAIN 
LIGHT. 

FOR DAY 2 THE CENTRAL ATLC MID LEVEL RIDGE MOVES WWD TO NEAR 
35N55W..CLOSING THE WEAKNESS ALONG 70W. ONE SHORTWAVE ALONG 68W 
MOVING NW WILL TRY TO NAVIGATE THROUGH THE WEAKNESS DAY 2. THE 
SHORTWAVE IN THE WRN CARIB MOVES TO 88W AND WEAKENS. THE 
SHORTWAVE IN THE ERN ATLC MOVES TO 42W. ON THE SURFACE TROUGHING 
DEVELOPS BETWEEN 60W AND 65W IN RESPONSE TO THE SHORTWAVE 
LIFTING NW. CARIB WINDS WEAKEN SLIGHTLY AND SHIFT TO MORE SELY E 
OF 70W DAY 2. ATLC WINDS REMAIN LIGHT W OF 65W AS WELL AS GULF 
WINDS. 

OUTLOOK PERIOD...

THE MID ATLC MID LEVEL RIDGE CONTINUES WWD TO NEAR 35N57W 
FURTHER PINCHING OFF THE WEAKNESS AND MOVING IT TO 73W. THE 
PLAINS MID LEVEL RIDGE REMAINS IN PLACE. THE SHORTWAVE IN THE 
EASTERLIES MOVES W TO 47W. ON THE SURFACE DAY 3 E TO SE WINDS 
OVER THE ERN CARIB PICK UP SOME TO 25 KT AS THE PRESSURE 
GRADIENT STRENGTHENS SOME. OTHERWISE ATLC WINDS REMAIN LIGHT W 
OF 60W WITH THE TROUGH MOVING NW TO 70W. GULF WINDS REMAIN LIGHT 
UNDER A WEAK RIDGE.

FOR DAY 4 THE SHORTWAVE IN THE EASTERLIES MOVES WNW TO 53W AND 
INTERCEPTS A CLOSED VORTEX STUCK UNDER THE MID ATLC MID LEVEL 
RIDGE. A WEAKNESS CONTINUES ALONG 70W BUT IS MORE PRONOUNCED N 
OF 30N. ON THE SURFACE DAY 4 BRISK E AND SE WINDS OVER THE CARIB 
SHIFT WWD DAY 4 BETWEEN 65W AND 75W AND WINDS OVER THE ATLC IN 
THE SE BAHAMAS PICK UP SOME TO 20 KT. THE ATLC RIDGE AXIS SHIFTS 
N TO 30N W OF 60W WITH MOSTLY LIGHT WINDS. GULF WINDS REMAIN 
LIGHT UNDER WEAK HIGH PRESSURE. 

DAY 5 FINDS THE PLAINS MID LEVEL RIDGE SHIFTING WWD ALLOWING A 
LARGE UPPER TROUGH OVER THE NE US TO SEND SHORTWAVES SE OFF THE 
MID ATLC COAST. AS A RESULT THE WEAKNESS IN THE PRESSURE FIELD 
STRENGTHENS ONCE AGAIN BETWEEN 60W AND 75W WITH THE MID ATLC MID 
LEVEL RIDGE BACKING OFF TO E OF 50W. THE SHORTWAVE IN THE 
EASTERLIES LIFTS NW AS A CLOSED CIRCULATION AT MID LEVELS TO 
NEAR 27N53W. ON THE SURFACE DAY 5 THE GFS MODEL SHOWS A WEAK 
SURFACE LOW TRYING TO DEVELOP NEAR 26N59W IN ASSOCIATION WITH 
THE ONE AT MID LEVELS. THE BRISK E AND SE WINDS OVER THE CARIB 
CONTINUE TO SHIFT WWD TO BETWEEN 70W AND 80W WITH 20 TO 25 KT. 
OTHERWISE WEAK PRESSURE GRADIENT WILL CONTINUE N OF 20N W OF 55W 
WITH MOSTLY LIGHT WINDS.

.WARNINGS...
ATLANTIC...NONE.
CARIBBEAN...NONE.
GULF OF MEXICO...NONE.

FORECASTER RRG