000
AGXX40 KNHC 211820
MIMATS

MARINE WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL 
220 PM FRI JUL 21 2006

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

UPPER DISCUSSION...A TUTT EXTENDS THROUGH UPPER CYCLONES AT 
34N33W...28N46W...31N59W...33N71W...26N87W AND 27N102W.  AN 
UPPER ANTICYCLONE IS OVER W CUBA RIDGING SW TO ANOTHER CENTERED 
NEAR 18N97W. GLOBAL MODELS BASICALLY CONTINUE THIS TROUGH 
PATTERN WELL INTO THE WEEKEND. THEN THE ANTICYCLONE SHIFTS N TO 
NEAR ANDROS ISLAND...WITH AN ELONGATED UPPER RIDGE FROM BERMUDA 
TO CENTRAL MEXICO...WHILE BROAD UPPER TROUGH DOMINATES THE 
EASTERN PORTION OF THE DISCUSSION AREA...ALL AROUND SUNRISE MON. 
THE ANTICYCLONE THEN SHIFTS RAPIDLY NW TO A PSN OVER THE NW GULF 
OF MEXICO EFFECTIVELY BLOCKING THE SE ADVANCE OF A SHORTWAVE 
OVER THE CENTRAL CONUS ON TUE AND WED. THE UPPER TROUGH OVER THE 
EASTERN PORTION CONTINUES WITH NOGAPS SUGGESTING A LARGE UPPER 
CYCLONE AT 25N60W WITH A TROUGH SW TO PANAMA. THE GFS MODEL 
SUGGESTS ABOUT THE SAME PATTERN...EXCEPT BOTH THE UPPER CYCLONE 
AND THE ANTICYCLONE ARE POSITIONED FURTHER E ALLOWING THE 
SHORTWAVE TO STALL OVER THE NW GULF OF MEXICO TUE NIGHT.        

LOW LEVELS...ATLC SURFACE RIDGE EXTENDS WSW ACROSS NORTHERN  
ATLC WATERS AND ACROSS N FL ALONG 29N INTO SE LA. THE RIDGE WILL 
SHIFT S TO STRAITS OF FL AND OVER CENTRAL GULF WATERS SATURDAY 
AND CONTINUE INTO MON...THEN SHIFT BACK TO THE NORTHERN WATERS 
BY LATE TUE. THIS WILL ALLOW A WEAK FRONT TO CREEP SE AND STALL 
OVER THE NORTHERN GULF OF MEXICO COASTAL PLAINS SUN AND 
MON...THEN PUSH N OF AREA ON TUE AS RIDGE SHIFTS BACK N. WINDS 
AND SEAS WILL INCREASE IN SLY FLOW...15-20 KT...OVER N WATERS 
WELL TO N OF RIDGE AXIS. THE PRESSURE GRADIENT WILL ALSO TIGHTEN 
IN THE BAY OF CAMPECHE WITH MOSTLY 15 KT EXPECTED. EXPECT LITTLE 
ADJUSTMENTS IN THIS PACKAGE FOR THE GULF AND SUBTROPICAL ATLC 
WATERS.  

A TROPICAL WAVE OVER THE CARIBBEAN ALONG 86W CONTINUES W AT 18 
KT UNDER THE CUBAN UPPER ANTICYCLONE. TSTMS HAVE FLARED NW 
CARIBBEAN AND OVER SW BAY OF CAMPECHE UNDER THE ASSOCIATED UPPER 
RIDGE. EXPECT CONTINUED ENHANCEMENT OF CONVECTION AS WAVE MOVES 
THROUGH BAY OF CAMPECHE TONIGHT AND SAT.
     
A TROPICAL WAVE ALONG 60W HAS MOVED W AT 15 KT THE PAST 24 
HOURS. SSMI DATA SUGGESTS 15-20 KT...SIGHTLY HIGHER THAN GFS. 
NWW3 HEIGHTS 1 FT ABOVE THE 3 BUOYS ALONG 15N BETWEEN 58W-53W AT 
12Z. I WILL PUSH WAVE THROUGH CARIBBEAN AT THE NEW SPEED OF 15 
KT...SLOWER THAN YESTERDAYS 18 KT...THUS PSN OF 68W SAT 
AFTERNOON.  AS ATLC RIDGE SHIFTS S AND GRADIENT TIGHTENS... 
EXPECTING ELY WINDS TO INCREASE ENTIRE CARIBBEAN 20-25 KT WITH 
GALE FORCE BEGINNING 06Z MON NEAR 13N75W AND CONTINUING WELL 
INTO TUE...AND LIKELY BELOW GALE AT SUNSET TUE.        

NEXT TROPICAL WAVE ALONG 46W MOVING W 12 KT PAST 48 HOURS. 
FORECAST PSN...53W SAT AFTERNOON.  MODELS SUGGEST WINDS E OF 
WAVE IN 15-20 KT RANGE.  
 
.WARNINGS...
ATLC...NONE.
CARIBBEAN...GALE CONDITIONS EXPECTED SAT NIGHT INTO TUE 
...AMZ084 AND AMZ086. 
GULF OF MEXICO...NONE.

FORECASTER FORMOSA