000
AXPZ20 KNHC 241001
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                        
1005 UTC SUN MAR 24 2013

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
THE ITCZ AXIS AND MONSOON TROUGH ARE PRESENTLY NOT IDENTIFIABLE 
ON THE 0600 UTC SURFACE ANALYSIS. DEEP CONVECTION IS NOT 
OBSERVED IN THE TROPICS.

...DISCUSSION...                                                 
         
AN UPPER LEVEL LONGWAVE TROUGH EXTENDS FROM THE CENTRAL U.S. SW 
TO ACROSS N/CENTRAL MEXICO AND TO AN UPPER LEVEL LOW MOVING NE 
AT 22N125W. THE TROUGH EXTENDS FROM THE LOW SSE TO THE EQUATOR 
AT 119W. MODELS FORECAST THE LOW TO CONTINUE TO HEAD NE TOWARDS
CENTRAL BAJA CALIFORNIA THROUGH EARLY ON MON WHILE WEAKENING 
INTO A SHORTWAVE TROUGH. A DRY ATMOSPHERE AHEAD OF IT DUE TO 
STRONG SUBSIDENCE ALOFT WILL INHIBIT THE LOW AND SUBSEQUENT 
TROUGH TO ACTIVATE ANY SIGNIFICANT PRECIPITATION BEFORE IT 
EXITS THE AREA. 
 
IN THE WAKE OF THE SHORTWAVE TROUGH...MOSTLY ZONAL FLOW SETS UP 
ACROSS JUST ABOUT THE ENTIRE AREA INTO EARLY NEXT WEEK WITH 
MODERATE TO STRONG UPPER LEVEL SUBSIDENCE WITH RESULTANT DRY   
AND STABLE ATMOSPHERIC CONDITIONS PREVAILING E OF 130W. A NARROW 
PLUME OF UPPER LEVEL MOISTURE IN THE FORM OF MAINLY BROKEN 
CIRRUS CLOUDS STREAMING EASTWARD IS OVER THE FAR WESTERN PORTION 
OF THE AREA FROM 24N TO 28N W OF 133W. THIS MOISTURE PLUME IS 
SPILLING OVER THE TOP OF A LARGE RIDGE CREST SEEN JUST W OF THE 
AREA. TO ITS NORTH A RATHER POTENT UPPER LOW LIFTING NE IS AT 
37N148W. THE RIDGE IS FORECAST TO CONTINUE TO SLIDE EWD INTO THE 
WESTERN PART OF THE AREA THROUGH MON...BUT WILL FLATTEN OUT ONCE 
THE UPPER LOW PULLS FARTHER NEWD TO INLAND THE PACIFIC NW 
SECTION OF THE U.S. A COLD FRONT ASSOCIATED WITH THE UPPER LOW 
IS CURRENTLY ABOUT 400 NM NW OF THE DISCUSSION AREA. THE FRONT 
IS FORECAST TO ENTER THE FAR NW WATERS EARLY THIS EVENING...THEN 
BEGIN TO WEAKEN AS IT STARTS TO SLOW DOWN AND EVENTUALLY BECOMES 
A DISSIPATING FRONT FROM ABOUT 32N134W TO 27N140W ON TUE AS HIGH 
PRES CENTERED N OF THE AREA DROPS SSW AHEAD OF THE FRONT WHILE 
ALSO WEAKENING. BESIDES A WIND SHIFT...THE FRONT IS EXPECTED TO 
HAVE VERY LITTLE IMPACT ON WINDS AND SEAS AS IT CROSSES INTO THE 
FAR NW WATERS.

OVER THE SERN PORTION OF THE AREA E OF THE ABOVE MENTIONED 
LONGWAVE TROUGH BROAD UPPER RIDGING IS ANCHORED BY AN 
ANTICYCLONE AT 06N95W. THIS FEATURE IS GENERALLY MAINTAINING
TRANQUIL ATMOSPHERIC CONDITIONS THERE WITH THE EXCEPTION
OF SMALL BURSTS OF TSTM CELLS WITHIN 30 NM OF A LINE FROM 03N92W 
TO 03N86W TO 03N79W. THIS ACTIVITY IS LOCATED UNDER MODERATE
DIVERGENT FLOW...WHICH IS ADVECTING SOME BLOW OFF CIRRUS CLOUDS 
FROM SCATTERED CONVECTION OVER ECUADOR AND NW COLOMBIA WWD TO 
NEAR 86W.

AT THE SURFACE TO LOW LEVELS...WEAKER HIGH PRES WILL MAINTAIN 
RATHER LIGHT WINDS ACROSS MUCH OF THE DISCUSSION AREA THROUGH 
THE NEXT 48 HRS...WITH THE EXCEPTION OF THE GULF OF TEHUANTEPEC 
WHERE MODELS SUGGEST THE NEXT GAP WIND EVENT TAKES PLACE. HAVE 
POSTED A GALE WARNING EFFECTIVE LATE MON NIGHT FOR THE GULF AS 
STRONG HIGH PRES IS EXPECTED TO SURGE SWD FROM THE GULF OF 
MEXICO TO ACROSS SERN MEXICO. THE RESULTANT PRES GRADEINT WILL 
GENERATE WINDS TO GALE FORCE THROUGH THE CHIVELA PASS...AND OUT 
INTO THE GULF OF TEHUANTEPEC AT THAT TIME...WITH SEAS FORECAST 
TO BUILD TO 12 FT.

$$
AGUIRRE