000
AXPZ20 KNHC 190215
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT MAY 19 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 
0300 UTC.

...SPECIAL FEATURE...
AT 0300 UTC...TROPICAL DEPRESSION ALETTA CENTERED NEAR 14.4N 
113.5W MOVING NE OR 40 DEG AT 3 KT. ESTIMATED MINIMUM PRES 1006 
MB. MAXIMUM SUSTAINED WINDS 30 KT GUSTS 40 KT. PLEASE REFER TO 
THE LATEST PUBLIC ADVISORY TCPEP1/WTPZ31 KNHC FOR MORE DETAILS. 
SCATTERED MODERATE CONVECTION IS WITHIN 90 NM NE QUADRANT OF 
ALETTA. ALETTA WILL CONTINUE TO WEAKEN THE NEXT 12 TO 24 HOURS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH EXTENDS FROM 08N82W TO 08N88W TO 14N95W TO 1006 
MB LOW PRES NEAR 12N101W TO 14N107W. ITCZ EXTENDS FROM 09N121W 
TO 05N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WITHIN 
120 NM S OF TROUGH AXIS E OF 100W.

...DISCUSSION...
THE MONSOON TROUGH THAT STRETCHES EASTWARD FROM TD ALETTA THROUGH
A BROAD AREA OF LOW PRES CENTERED NEAR 13N101W TO A DEVELOPING 
LOW NEAR 08N86W REMAINS FAIRLY ACTIVE CONVECTIVELY WHILE THE LOWS
EMBEDDED WITHIN THE TROUGH HAVE BECOME WEAKER OVER THE PAST 6-12 
HOURS BASED ON SCATTEROMETER DATA. MODERATE W WIND CONVERGENCE IS
EVIDENT S OF THE TROUGH BETWEEN 84W AND 98W...AND A LARGE AREA OF
MODERATE TO STRONG CONVECTION IS LOCATED BETWEEN 87W AND 93W. A 
BROAD UPPER LEVEL ANTICYCLONE CENTERED OVER HONDURAS NEAR 13N87W 
IS ENHANCING CONVECTIVE ACTIVITY E OF 105W.

EXPECT ALETTA TO WEAKEN FURTHER OVER THE NEXT 12-24 HOURS INTO A 
REMNANT LOW WHILE THE OTHER TWO AREAS OF LOW PRES REMAIN NEARLY 
STATIONARY WITH LITTLE CHANGE IN WINDS OR SEAS. THE GFS MODEL IS 
CONSIDERED AN OUTLIER FOR ITS AGGRESSIVE DEVELOPMENT OF THE LOW 
CURRENTLY NEAR 13N101W OVER THE NEXT FEW DAYS. UKMET AND ECMWF 
ARE MORE RESTRAINED IN DEVELOPING THE BROAD LOW PRES AREA LATER 
THIS WEEKEND AND ARE THE BASIS FOR THE EXTENDED FORECAST GRIDS.

EXPECT THE MONSOON TROUGH E OF 115W TO CONTINUE TO BE PRIMARY 
SYNOPTIC FEATURE THROUGH THE WEEKEND. GENTLE TO MODERATE TRADE 
WINDS WILL PREVAIL W OF 120W WITH SEAS SUBSIDING TO 4-6 FT OVER 
MOST OF THE DISCUSSION AREA BY SUN.

WE MAY SEE ENHANCED N-NE WINDS SPILLING ACROSS THE CHIVELA PASS 
INTO THE GULF OF TEHUANTEPEC SUN THROUGH MON BASED ON GFS AND 
ECMWF MODELS...BUT THE KEY FACTOR FOR 20-25 WINDS TO DEVELOP 
WILL BE FORMATION OF A SURFACE TROUGH OVER THE YUCATAN PENINSULA 
WHILE HIGH PRES BUILDS S ALONG THE GULF COAST OF MEXICO. ONSET 
MAY OCCUR IN ABOUT 48 HOURS...BUT STILL LOOKS UNLIKELY FOR NOW.

$$
MUNDELL