000
AXPZ20 KNHC 070336
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU NOV 07 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0330 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 
PUSH THROUGH THE CHIVELA PASS REGION INCREASING SURFACE FLOW TO 
20-25 KT INITIALLY...THEN INCREASE TO GALE FORCE BETWEEN 18-21 
UTC THU. A STRONGER NORTHERLY SURGE TO 40 KT IS ANTICIPATED LATE 
THU NIGHT INTO EARLY FRIDAY. SEAS OF 8-10 FT THU AFTERNOON WILL 
BUILD TO A RANGE OF 10 TO 14 FT BY EARLY THU EVENING.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...              
THE MONSOON TROUGH AXIS EXTENDS FROM 08N79W TO 13N90W TO 10N97W 
TO 10N111W TO 11N124W. THE ITCZ AXIS EXTENDS FROM 08N124W TO 
07N140W. SCATTERED MODERATE ISOLATED/STRONG CONVECTION IS WITHIN 
120 NM S OF THE TROUGH BETWEEN 120W-123W.

...DISCUSSION...                                            
WATER VAPOR IMAGERY INDICATES A MIDDLE TO UPPER LEVEL TROUGH 
AXIS THAT EXTENDS FROM THE NORTHERN U.S. PLAINS SOUTHWESTWARD TO 
OVER NW MEXICO TO AN UPPER LOW MOVING WSW NEAR 21N118W...AND S 
TO A BASE NEAR 11N120W. 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 DIFFLUENCE IS 
GENERATING A FEW POCKETS OF SCATTERED MODERATE CONVECTION FROM 
16N-20N BETWEEN 108W-109W. TO THE WEST...AN UPPER LEVEL 
ANTICYCLONE IS CENTERED JUST W OF THE AREA NEAR 12N145W WITH A 
RIDGE AXIS EXTENDING N-NEWD TO BEYOND 32N125W. THE RIDGING ALOFT 
SUPPORTS A BROAD SURFACE RIDGE ANCHORED BY A 1024 MB HIGH 
CENTERED N OF THE AREA NEAR 36N129W. THE HIGH WILL SLOWLY MOVE 
EASTWARD AND WEAKEN THROUGH THU ALLOWING FOR THE SMALL AREA OF 
NE-E 20 KT TRADES OVER THE WATERS FROM 13N TO 26N BETWEEN 120W 
AND 135W WITH SEAS TO 8 FT IN NW SWELLS TO DIMINISH TO AROUND 10-
15 KT WITH SEAS LESS THAN 8 FT.
 
OVER THE FAR EASTERN PORTION...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 TO ISOLATED 
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.

GULF OF CALIFORNIA...NW-N 20-25 KT WINDS N OF 27N ARE FORECAST 
TO DIMINISH TO THU AFTERNOON AS THE CULPRIT TIGHT PRES GRADIENT 
DUE TO STRONG HIGH PRES OVER THE SW U.S. AND TROUGHING OVER NW 
MEXICO RELAXES. 

$$
AGUIRRE