000
AXPZ20 KNHC 061539
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED NOV 06 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.

...SPECIAL FEATURES...                                          
A STRONG COLD FRONT IS FORECAST TO MOVE THROUGH THE SW GULF OF 
MEXICO THURSDAY WITH A GALE FORCE GAP WIND EVENT BEGINNING IN 
THE GULF OF TEHUANTEPEC BEGINNING SHORTLY BEFORE 07/1200 UTC. 
GFS AND NAM MODEL GUIDANCE SUGGESTS THAT NORTHERLY WINDS WILL 
EMERGE FROM THE CHIVELA PASS REGION INCREASING SURFACE FLOW TO 
20-25 KT INITIALLY...THEN INCREASE TO GALE FORCE BY 07/1800 UTC. 
A STRONGER NORTHERLY SURGE TO 40 KT IS ANTICIPATED EARLY FRIDAY 
MORNING DUE TO PEAK DRAINAGE FLOW. SEAS WILL BUILD TO A RANGE OF 
10 TO 14 FT BY FRIDAY.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 13N90W TO 11N94W 
TO 12N100W TO 09N110W TO 12N120W TO 09N127W. THE ITCZ AXIS 
EXTENDS FROM 09N127W TO 07N140W. WIDELY SCATTERED MODERATE 
CONVECTION IS FROM 03N TO 08N E OF 80W...AND FROM 05N TO 08N 
BETWEEN 125W AND 129W. ISOLATED MODERATE CONVECTION IS WITHIN 
150 NM S OF AXIS BETWEEN 83W AND 88W...AND BETWEEN 105W AND 124W.

...DISCUSSION...                                            
WATER VAPOR IMAGERY INDICATES A MIDDLE TO UPPER LEVEL TROUGH 
AXIS EXTENDS FROM THE NORTHERN U.S. PLAINS SOUTHWESTWARD TO OVER 
NW MEXICO THEN TO A BASE NEAR 14N120W. MOSTLY DRY AIR AND 
OVERALL STABLE CONDITIONS ARE ASSOCIATED WITH THE TROUGH OVER 
THE FORECAST WATERS NW OF THE TROUGH AXIS WITH ONLY SPARSE 
MOISTURE ADVECTING NORTHEASTWARD FROM THE DEEP TROPICS ACROSS 
MEXICO. THIS MOISTURE ALONG WITH MARGINAL MIDDLE TO UPPER LEVEL 
DIFFLUENT IS GENERATING A FEW AREAS OF SHOWERS AND TSTMS WITHIN 
120 NM EITHER SIDE OF A LINE FROM 15N113W TO THE MEXICO COAST 
NEAR 22N106W. TO THE WEST...AN UPPER LEVEL ANTICYCLONE IS 
CENTERED NEAR 12N142W AND EXTENDS A RIDGE AXIS NORTH-
NORTHEASTWARD TO BEYOND 32N125W. THE RIDGING ALOFT SUPPORTS A 
BROAD SURFACE RIDGE ANCHORED BY A 1028 MB HIGH CENTERED NORTH OF 
THE AREA NEAR 37N131W. THE HIGH WILL GRADUALLY DRIFT EASTWARD 
AND RESULT IN A STRENGTHENED PRESSURE GRADIENT ACROSS THE GULF 
OF CALIFORNIA REGION. NW TO N WINDS ARE FORECAST TO MAINTAIN A 
RANGE OF 20 TO 25 KT THROUGH LATE THURSDAY WITH SEAS BUILDING TO 
8 FT.

FINALLY...AN UPPER LEVEL LOW CENTERED NEAR 17N99W CONTINUES TO 
RETROGRADE AS IT HAS THE PAST FEW DAYS OVER CENTRAL AMERICA AND 
GENERATING AN AREA OF WIDELY SCATTERED SHOWERS AND TSTMS 
OFFSHORE OF THE MEXICO COAST FROM 14N TO 18N BETWEEN 98W AND 
103W. OTHERWISE THE REMAINDER OF THE EASTERN WATERS REMAINS 
FAIRLY BENIGN WITH WINDS LESS THAN 20 KT AND SEAS LESS THAN 8 FT 
WITH THE ONLY EXCEPTION BEING THE GULF OF TEHUANTEPEC GAP WIND 
EVENT.

$$
HUFFMAN