Eastern Pacific Tropical Weather Discussion

000
AXPZ20 KNHC 202137
TWDEP 

TROPICAL WEATHER DISCUSSION                                
NWS NATIONAL HURRICANE CENTER MIAMI FL                          
2205 UTC MON MAY 20 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 
2015 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 9N85W TO 10N98W 
TO 07N117W TO 12N124W. THE ITCZ AXIS EXTENDS FROM 10N126W TO 
05N135W TO 07N140W. CLUSTERS OF MODERATE TO STRONG CONVECTION 
ARE WITHIN 180 NM S OF THE MONSOON TROUGH BETWEEN 77W AND 111W. 
SIMILAR CONVECTION IS FROM 05N TO 12N BETWEEN 111W AND 124W.  
SCATTERED MODERATE CONVECTION IS WITHIN 180 NM N OF THE ITCZ 
BETWEEN 132W AND 136W.

...DISCUSSION... 

THE 1012 MB LOW REMNANT OF ALVIN IS CENTERED NEAR 12N126W ALONG 
A NORTH-SOUTH ORIENTATED TROUGH THAT EXTENDS FROM 10N125W TO 
14N125W. THE MOST RECENT ASCAT PASS PROVIDED OBSERVATIONS OF 20-
25 KT WINDS WITHIN 120 NM N SEMICIRCLE OF LOW CENTER. THIS 
SYSTEM IS GENERATING MAXIMUM SEAS OF 10 FT. A BROAD MIX OF SWELL 
IS MAINTAINING SEAS UP TO 8 FT ELSEWHERE WITHIN THE AREA BOUNDED 
BY 11N-16N BETWEEN 121W-130W. MARINE GUIDANCE SUGGESTS THAT THE 
REMNANT LOW OF ALVIN WILL CONTINUE TO MOVE MAINLY WESTWARD 
DURING THE NEXT 48 HOURS WITH AN AREA OF FRESH WINDS WITHIN 
ABOUT 120 NM TO THE N OF THE LOW CENTER.  

A 1030 MB HIGH PRES LOCATED N OF AREA NEAR 36N137W EXTENDS A 
RIDGE SE TO NEAR 20N112W. PRES GRADIENT TIGHTENS ON THE EAST 
SIDE OF THE RIDGE PRODUCING NW WINDS OF 10-15 KT ALONG THE 
ENTIRE WESTERN SHORE OF THE BAJA CALIFORNIA PENINSULA WITH SEAS 
OF 4-6 FT. IN ADDITION...A SURGE OF NORTHERLY WINDS AT 15-20 KT 
CONTINUES ACROSS THE N-CENTRAL PACIFIC WATERS...ROUGHLY N OF 28N 
BETWEEN 119W AND 128W WITH SEAS TO 9 FT PRIMARILY IN N SWELL. 
THESE NORTHERLY WINDS ARE EXPECTED TO INCREASE TO 20-25 KT EARLY 
ON WED AS HIGH PRES N OF AREA INTENSIFIES. 


$$
NR/MKH