000
AXPZ20 KNHC 201525
TWDEP
TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1500 UTC.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH AXIS EXTENDS FROM 09N78W TO 11N95W TO 07N115W TO
09N122W...THEN RESUMES AT 10N126W TO 07N132W. THE ITCZ AXIS
CONTINUES FROM 07N132W TO 08N140W. CLUSTER OF MODERATE TO STRONG
CONVECTION IS FROM 04N TO 08N E OF 80W TO THE COAST OF COLOMBIA.
SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 05N
TO 08N BETWEEN 80W AND 84W...FROM 06N TO 12N BETWEEN 100W AND
109W...FROM 06N TO 10N BETWEEN 117W AND 127W AND FROM 05N TO 11N
W OF 135W.
...DISCUSSION...
THE 1009 MB REMNANTS OF ALVIN ARE CENTERED NEAR 12.5N123W ALONG
A NORTH-SOUTH ORIENTATED TROUGH THAT EXTENDS FROM 9N123W TO
15N123W. AN EARLIER HIGH RESOLUTION ASCAT PASS PROVIDED
OBSERVATIONS OF 20-30 KT WINDS WITHIN 150 NM N SEMICIRCLE OF LOW
CENTER. THIS SYSTEM IS GENERATING MAXIMUM SEAS OF 11 FT. A BROAD
MIX OF SWELL IS MAINTAINING SEAS OF 7-10 FT ELSEWHERE WITHIN THE
AREA BOUNDED BY 11N-17N BETWEEN 120W-130W. FARTHER WEST...AN
AREA OF ENHANCED NE TRADES AT 15-20 KT IS NOTED WITH SEAS TO 9
FT...ACROSS THE TROPICS FROM 10N-15N W OF 136W. MARINE GUIDANCE
SUGGESTS THAT THE REMNANT LOW OF ALVIN WILL CONTINUE TO MOVE
MAINLY WESTWARD DURING THE NEXT COUPLE OF DAYS WITH AN AREA OF
FRESH TO STRONG WINDS WITHIN ABOUT 150 NM TO THE N OF THE LOW
CENTER.
A 1033 MB HIGH PRES LOCATED N OF AREA NEAR 38N136W EXTENDS A
RIDGE SE TO NEAR 18N112W. PRES GRADIENT TIGHTENS ON THE EAST
SIDE OF THE RIDGE PRODUCING NW WINDS OF 10-15 KT ALONG THE
ENTIRE W 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 126W WITH SEAS TO 9 FT PRIMARILY IN N SWELL.
THESE NORTHERLY WINDS WILL INCREASE TO 20-25 KT TUE NIGHT INTO WED AS
HIGH PRES N OF AREA INTENSIFIES.
LOW PRESSURE IS EXPECTED TO DEVELOP OVER THE SW CARIBBEAN ON WED
AS A TROPICAL WAVE CURRENTLY OVER THE E CARIBBEAN MOVES INTO THE
AREA. THE LOW PRESSURE WILL MOVE ACROSS CENTRAL AMERICA INTO THE
E PACIFIC NEAR 09N87W LATE IN THE WEEK.
ALOFT...A RIDGE/TROUGH/RIDGE PATTERN IS OBSERVED ACROSS THE
FORECAST WATERS. A TROPICAL MOISTURE PLUME...ORIGINATING FROM
THE CONVECTIVE DEBRIS MOISTURE FROM FORMER TROPICAL CYCLONE
ALVIN...EXTENDS ALL THE WAY NE BETWEEN 110W AND 120W TO SOUTHERN
BAJA CALIFORNIA INTO MAINLAND MEXICO. UPPER DIFFLUENCE IS
HELPING TO INDUCE THE STRONG CONVECTION NEAR THE COAST OF
COLOMBIA.
$$
GR
