Eastern Pacific Tropical Weather Discussion

000
AXPZ20 KNHC 192129
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC SUN MAY 19 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.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 08N90W TO 
07N103W. THE ITCZ AXIS EXTENDS FROM 07N103W TO 10N117W...THEN 
RESUMES FROM 09N123W TO 06N140W. ISOLATED TO SCATTERED MODERATE 
CONVECTION IS S OF THE MONSOON TROUGH TO 05N E OF 80W...WITHIN 
180 NM S OF THE MONSOON TROUGH BETWEEN 84W AND 90W...WITHIN 90 
NM EITHER SIDE OF THE MONSOON TROUGH BETWEEN 91W AND 94W... 
WITHIN 120 NM EITHER SIDE OF THE MONSOON TROUGH BETWEEN 97W AND 
100W...AND ALSO WITHIN 150-180 NM N OF THE ITCZ W OF 122W.

LOW PRES...THE REMNANTS OF ALVIN...IS NEAR 12.5N121W WITH A 
TROUGH EXTENDING FROM 15N121W TO THE LOW TO 07N121W. ISOLATED TO 
SCATTERED MODERATE CONVECTION IS WITHIN 240 NM NE OF THE TROUGH.

...DISCUSSION...                                                

1034 MB SURFACE HIGH PRES IS POSITIONED WELL N OF THE AREA NEAR 
39N134W WITH A RIDGE AXIS EXTENDING S-SE OF THE HIGH THROUGH 
32N131W TO 15N106W. THIS RIDGING COMBINED WITH TROUGHING OVER 
INTERIOR CALIFORNIA IS PRODUCING GALE FORCE WINDS FROM THE 
REDWOOD COAST OF CALIFORNIA S TO THE CHANNEL ISLANDS. THESE 
WINDS ARE GENERATING SEAS OF 8-11 FT WHICH ARE PROPAGATING INTO 
THE DISCUSSION WATERS N OF 29N BETWEEN 119W AND 123W. THESE SEA 
HEIGHTS WILL REACH TO 28N BETWEEN 119W AND 127W BY MON AFTERNOON 
...WITH LITTLE CHANGE FROM THAT POINT THROUGH TUE AFTERNOON.

THE REMNANTS OF ALVIN WHICH ARE ALSO DESCRIBED IN THE CONVECTION 
SECTION ABOVE WILL CONTINUE TO MOVE W AROUND 10 KT. A RECENT 
ASCAT SCATTEROMETER PASS INDICATED FRESH TO STRONG WINDS WITHIN 
270 NM IN THE N QUADRANT OF THE LOW ALONG WITH 9-11 FT SEAS... 
WHICH WERE MEASURED BY A RECENT ALTIMETER PASS. MODERATE TO 
FRESH WINDS ARE NEARBY IN THE W CENTRAL WATERS FROM 08N TO 14N W 
OF 123W WHERE SEAS TO 9 FT IN MIXED NE AND SW SWELL ARE PRESENT. 
THE LOW IS FORECAST TO DISSIPATE DURING THE NEXT 24 HOURS WITH 
THE REMAINING TROUGH CONTINUING WESTWARD...EXTENDING FROM 
15N124W TO 11N125W TO 07N129W BY TUE AFTERNOON. WINDS WILL 
DIMINISH TO 20 KT OR LESS ACROSS THE BOARD IN THIS AREA BY MON 
AFTERNOON...WHILE LINGERING SEAS OF 8-10 FT WILL LINGER W OF THE 
TROUGH THROUGH 48 HOURS.

ALOFT...A TROPICAL MOISTURE PLUME APPROXIMATELY 390 NM WIDE 
EXTENDS FROM THE DEEP TROPICS FROM 04N TO 12N W OF 120W...THEN 
CONTINUES TO THE NE JUST S OF THE SOUTHERN TIP OF THE BAJA 
CALIFORNIA PENINSULA TO ACROSS CENTRAL MEXICO. DRY AND STABLE 
AIR IS PRESENT ACROSS THE WATERS N OF THIS PLUME...EXCEPT W OF 
132W WHERE ADDITIONAL TROPICAL MOISTURE S OF HAWAII IS ADVECTING 
INTO THE DISCUSSION WATERS. ELSEWHERE...MOISTURE ALONG THE 
MONSOON TROUGH AS IS DESCRIBED IN THE CONVECTION SECTION 
CONTINUES TO FAN OUT WHILE MOVING WESTWARD TO 110W AROUND AN 
UPPER ANTICYCLONE CENTERED OVER THE GULF OF TEHUANTEPEC AREA.

$$
LEWITSKY