000
AXPZ20 KNHC 142133
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC TUE MAY 14 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...SPECIAL FEATURES...

A BROAD AREA OF 1008 MB LOW PRES HAS FORMED NEAR 07N99W...OR 
ABOUT 650 MILES S OF ACAPULCO MEXICO. A 1632 UTC HIGH RESOLUTION 
ASCAT SCATTEROMETER PASS INDICATED 20 TO 30 KT WINDS WITHIN 120 
NM OF THE LOW IN THE E SEMICIRCLE...WITH 20 TO 25 KT WINDS 
WITHIN 150 NM IN THE SW QUADRANT OF THE LOW. SEAS OF 8 TO 11 FT 
ACCOMPANY THESE WINDS. ASSOCIATED CONVECTION WITH THE LOW IS AS 
IS DESCRIBED IN THE NEXT SECTION. GRADUAL DEVELOPMENT OF THIS 
SYSTEM IS POSSIBLE DURING THE NEXT COUPLE OF DAYS AS IT MOVES 
WEST-NORTHWEST AT AROUND 10 KT...AND IT HAS A MEDIUM CHANCE 
OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 06N77W TO 08N89W TO 1008 MB 
LOW PRES NEAR 07N99W TO 08N120W. THE ITCZ AXIS EXTENDS FROM 
08N120W TO 08N125W TO 07N140W. SCATTERED MODERATE TO STRONG 
CONVECTION IS N OF 03N E OF 82W...FROM 05N TO 08N BETWEEN 84W 
AND 89W...AND ALSO WITHIN 90 TO 120 NM IN THE NE SEMICIRCLE OF 
THE LOW. SCATTERED MODERATE CONVECTION IS FROM 07N TO 15N 
BETWEEN 100W AND 104W...AND ALSO WITHIN 120 TO 180 NM S OF THE 
MONSOON TROUGH BETWEEN 101W AND 108W.

...DISCUSSION...

AN UPPER LEVEL TROUGH IS ACROSS THE FAR NW PORTION OF THE 
DISCUSSION AREA FROM 32N128W TO 24N140W...WITH A DOWNSTREAM 
UPPER LEVEL RIDGE EXTENDING FROM 32N119W TO 22N122W. MODERATE TO 
STRONG SUBSIDENCE WITH DRY STABLE AIR AT THE MIDDLE AND UPPER 
LEVELS IS GENERALLY N OF A LINE FROM 22N106W TO 13N140W. AN 
UPPER LEVEL TROUGH EXTENDS FROM A CYCLONIC CIRCULATION CENTERED 
OVER NW MEXICO NEAR 30N111W TO 25N115W. A 70 TO 90 KT JETSTREAM 
ACCOMPANIES THIS TROUGH FROM SW OF THE SOUTHERN TIP OF THE BAJA 
PENINSULA TO ACROSS NORTHERN MEXICO INTO TEXAS.

AT THE SURFACE...HIGH PRES RIDGING DOMINATES THE WATERS N OF THE 
ITCZ AND MONSOON TROUGH W OF 110W. MAINLY MODERATE ANTICYCLONIC 
WINDS AND SEAS OF 5 TO 7 FT COVER THIS AREA WITH LITTLE CHANGE 
FORECAST THROUGH THE NEXT 48 HOURS.

FRESH TO NEAR GALE FORCE NORTHERLY WINDS PERSIST IN THE GULF OF 
TEHUANTEPEC ALONG WITH 8 TO 12 FT SEAS...INDUCED BY A TIGHT PRES 
GRADIENT OVER THE REGION WITH HIGH PRES RIDGING ALONG EASTERN/ 
COASTAL MEXICO...TROUGHING N OF THE ISTHMUS OF TEHUANTEPEC IN 
THE BAY OF CAMPECHE...AND LOW PRES TO THE S TO SW OF THE GULF... 
ASSOCIATED WITH THE MONSOON TROUGH. THESE WINDS AND SEAS ARE 
FORECAST TO DIMINISH BELOW ADVISORY CRITERIA BY WED AFTERNOON AS 
THE PRES GRADIENT SLACKENS.

EASTERLY WINDS OF 20 TO 25 KT ARE BLOWING THROUGH THE GULF OF 
PAPAGAYO AS INDICATED BY RECENT ASCAT SCATTEROMETER PASSES. SEAS 
OF 8 TO 11 FT ACCOMPANY THESE WINDS. THESE CONDITIONS ARE 
FORECAST TO GRADUALLY DIMINISH AND SUBSIDE BY WED EVENING.

MODEL GUIDANCE FORECASTS NORTHERLY WINDS OF 20 TO 25 KT 
DEVELOPING IN THE GULF OF PANAMA LATE TONIGHT N OF THE MONSOON 
TROUGH AS LOW PRES OVER INTERIOR COLOMBIA DEEPENS. THESE WINDS 
ARE THEN FORECAST TO DIMINISH BY LATE WED NIGHT AS THE LOW THEN 
WEAKENS.

$$
LEWITSKY