000
AXPZ20 KNHC 160324
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED NOV 16 2011

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.

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

THE MONSOON TROUGH IS ALONG 10N86W TO 1009 MB LOW PRES NEAR 
09N90W TO 09N108W. THE INTERTROPICAL CONVERGENCE ZONE AXIS 
EXTENDS FROM 10N120W TO 07N135W TO 08N140W. SCATTERED MODERATE 
CONVECTION IS WITHIN 90 NM EITHER SIDE OF THE ITCZ BETWEEN 130W 
AND 134W.

...DISCUSSION...

AN UPPER LEVEL RIDGE IS ACROSS THE NW PORTION OF THE DISCUSSION 
AREA WITH THE MEAN AXIS FROM 32N134W TO 20N122W. MID TO HIGH 
LEVEL MOISTURE IS INTRUDING OVER THE W PORTION OF THE AREA W OF 
130W AS INDICATED BY WATER VAPOR SATELLITE IMAGERY. MAINLY ZONAL 
WESTERLY UPPER LEVEL FLOW IS E OF THE RIDGE WITH 40-50 KT JET 
LEVEL WINDS INCREASING TO 70-90 KT OVER NORTHERN MEXICO. STRONG 
SUBSIDENCE WITH DRY AND STABLE AIR AT THE MIDDLE AND UPPER 
LEVELS IS ACROSS THE AREA N OF 20N E OF 130W. AN UPPER LEVEL 
ANTICYCLONIC CIRCULATION IS SW OF MEXICO NEAR 14N98W WITH 
SIMILARLY DRY AND STABLE AIR N OF 10N E OF 110W.

IN THE DEEP TROPICS...AN UPPER LEVEL CYCLONIC CIRCULATION IS 
CENTERED NEAR 02N115W. AN UPPER LEVEL RIDGE IS W OF THE CYCLONIC 
CIRCULATION EXTENDING FROM 04N140W TO 10N122W. UPPER LEVEL 
DIFFLUENT FLOW IS ENHANCING CONVECTION ALONG THE ITCZ AS 
DESCRIBED IN THE SECTION ABOVE.

AT THE SURFACE...1029 MB HIGH PRES IS NW OF THE DISCUSSION AREA 
NEAR 37N137W WITH A RIDGE EXTENDING INTO THE AREA NEAR 32N129W 
CONTINUING TO NEAR 17N105W. EARLIER SCATTEROMETER PASSES INDICATE
WINDS LESS THAN 20 KT ACROSS THE RIDGING...ALTHOUGH AN AREA OF 
NW SWELL OF 8-10 FT EXISTS N OF 27N BETWEEN 120W AND 130W AS 
CAPTURED BY AN EARLIER ALTIMETER PASS. THIS SWELL WILL GRADUALLY 
SUBSIDE TO 8 FT WHILE BECOMING CONFINED TO N OF 29N IN 48 HOURS.

A WEAKENING 1009 MB AREA OF LOW PRES IS EMBEDDED IN THE MONSOON
TROUGH NEAR 09N90W WITH SCATTERED SHOWERS NEAR THE LOW CENTER.
A PAIR OF SURFACE TROUGHS ARE ANALYZED ALONG THE ITCZ. THE FIRST 
EXTENDS FROM 14N115W TO 08N119W. SCATTERED MODERATE AND ISOLATED 
STRONG CONVECTION IS FROM 09N TO 14N E OF THE TROUGH TO 113W. 
THE SECOND TROUGH EXTENDS FROM 14N139W TO W OF THE AREA AT 
09N141W. CONVECTION HAS DIMINISHED WITH THIS TROUGH. NO 
DEVELOPMENT OF THESE FEATURES IS ANTICIPATED DURING THE NEXT 48 
HOURS.

ELSEWHERE AT THE SURFACE...NW SWELL TO 9 FT COVERS THE W CENTRAL 
WATERS AS CONFIRMED BY AN EARLIER ENVISAT ALTIMETER PASS. THIS 
SWELL WILL GRADUALLY SUBSIDE AND SHRINK IN COVERAGE THROUGH THE 
NEXT 48 HOURS...ENCOMPASSING THE WATERS FROM 10N TO 14N BETWEEN 
120W AND 127W BY THU EVENING. A TIGHT PRES GRADIENT WILL DEVELOP
OVER THE GULF OF CALIFORNIA REGION WED EVENING AND MODEL 
GUIDANCE INDICATES NW-N 20 KT WINDS OVER THE NORTHERN GULF 
BEGINNING 00 UTC THU...DIMINISHING BY 00 UTC FRI.

GAP WINDS...THE NEXT COLD FRONT WILL MOVE THROUGH THE SW GULF OF 
MEXICO THU WITH NORTHERLY WINDS FUNNELING THROUGH THE CHIVELA 
PASS BEHIND IT. THE LATEST MODEL GUIDANCE CONTINUES TO INDICATE 
A HIGH LIKELIHOOD FOR GALE FORCE WINDS IN THE GULF OF 
TEHUANTEPEC ONCE THE FRONT PASSES BY TO THE N...AND A GALE 
WARNING HAS BEEN ISSUED BEGINNING AT 00 UTC FRI.

$$
LEWITSKY