000
AXPZ20 KNHC 110327
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN MAR 11 2012

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0215 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

ITCZ FROM 04N87W TO 02N100W TO THE EQUATOR ALONG 110W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS WITHIN 100 NM N OF 
AXIS BETWEEN 87W AND 94W. ISOLATED MODERATE CONVECTION IS S OF 
04N BETWEEN 98W AND 106W. A DIFFLUENT PATTERN ALOFT IS HELPING 
TO INDUCE THIS CONVECTIVE ACTIVITY.

...DISCUSSION...

A LARGE MIDDLE TO UPPER LEVEL CUTOFF LOW IS OVER THE DESERT SW 
SECTION OF THE U.S. WITH A TROUGH EXTENDING SW ACROSS NW MEXICO 
AND BAJA CALIFORNIA TO NEAR 22N110W. WATER VAPOR IMAGERY SHOWED 
MODERATE TO STRONG SUBSIDENCE W OF THE TROUGH AXIS COVERING THE 
AREA N OF 20N E OF 120W. ELSEWHERE...RELATIVELY ZONAL FLOW 
DOMINATED THE UPPER LEVELS OF THE AREA...WITH A BROAD RIDGE W OF 
120W. A SECOND RIDGE IS E OF THE TROUGH FROM NEAR 07N102W ACROSS 
NORTHERN CENTRAL AMERICA AND SE MEXICO INTO THE W GULF OF 
MEXICO...WHILE MIDDLE TO UPPER LEVEL TROUGHING CONTINUED FROM 
EASTERN CUBA SW INTO THE FAR EPAC THROUGH COSTA RICA AND WESTERN 
PANAMA...PRODUCING SUBSIDENCE AND STABLE CONDITIONS THERE. A 
VIGOROUS UPPER LEVEL LOW WELL W OF THE AREA IS ACCOMPANIED BY A 
VERY LARGE SWATH OF DEEP LAYER ATMOSPHERIC MOISTURE TO ITS E AND 
SE. STRONG UPPER LEVEL SW WINDS ARE ADVECTING THIS MOISTURE NE 
TO JUST OVER THE FAR WESTERN PORTION OF THE DISCUSSION AREA. 

A WEAKENING STATIONARY FRONT IS OVER THE FAR NW CORNER OF THE 
AREA...AND IS FORECAST TO SLOWLY WASH OUT THROUGH SUN AS STRONG 
HIGH PRES BUILDS EASTWARD ACROSS THE NORTHERN WATERS. LONG 
PERIOD NW SWELLS WITH SIGNIFICANT WAVE HEIGHTS AS HIGH OF 12 FT 
HAVE MOVED INTO THE NW WATERS IN THE WAKE OF THE FRONT.

ELSEWHERE AT THE SURFACE...A RIDGE EXTENDED THROUGH 31N140W SE 
ACROSS THE STATIONARY FRONT TO NEAR 20N110W. A TIGHT PRES 
GRADIENT TO THE S OF THE RIDGE WAS INDUCING NE-E 20-25 KT TRADE 
WINDS FROM 04N-20N W OF 120W...WITH SEAS GENERALLY 9-12 FT.  
SCATTEROMETER DATA CONFIRMED THE PRESENCE OF THESE WINDS SPEEDS. 
THIS AREA OF TRADES IS FORECAST TO CHANGE LITTLE OVER THE NEXT 
24 HRS...THEN DIMINISH BOTH IN AREAL COVERAGE AND IN WIND SPEEDS 
BY 48 HRS AS THE HIGH WEAKENS IN RESPONSE TO A COLD FRONT THAT 
SKIRTS THE FAR NORTHERN WATERS AT THAT TIME.

GAP WINDS... 
THE GULF OF TEHUANTEPEC...THE MOST RECENT SCATTEROMETER PASS 
SHOWED 20-30 KT WINDS THERE. THESE WINDS WILL DIMINISH TO LESS 
THAN 20 KT IN ABOUT 24 HRS.

THE GULF OF PAPAGAYO...FRESH TRADES ACROSS THE CARIBBEAN 
CONTINUE TO FUEL GAP WIND FLOW ACROSS CENTRAL AMERICA THEN 
THROUGH THE GULF OF PAPAGAYO AND WELL DOWNWIND TO NEAR 93W.  
WINDS ARE GENERALLY 20-25 KT...WITH SEAS OF 8-11 FT. LITTLE 
SIGNIFICANT CHANGE IS EXPECTED ACROSS THIS AREA IN THE NEXT 
24-48 HOURS. THE LARGEST AREAL EXTEND OF THE FRESH WINDS WILL 
BE IN THE EARLY MORNING HOURS WITH THE AID OF THE NOCTURNAL 
DRAINAGE FLOW.

THE GULF OF PANAMA...TRADES IN THE SOUTHWESTERN CARIBBEAN SEA 
WILL CONTINUE TO SUPPORT PULSES OF FRESH NORTHERLY FLOW ACROSS 
THE ISTHMUS OF PANAMA AND ACROSS THE GULF OF PANAMA AND DOWNWIND 
TOWARDS THE SW DURING THE NEXT 48 HOURS...WHERE SEAS WILL REMAIN 
IN THE 6 TO 9 FT RANGE. LITTLE CHANGE HERE IS EXPECTED DURING 
THE NEXT 24-48 HOURS.

$$
GR