000
AXPZ20 KNHC 142130
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED NOV 14 2012

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...
MONSOON TROUGH AXIS EXTENDS FROM 08N78W TO 08N85W TO 07N100W 
THEN ITCZ CONTINUES TO 10N118W TO 09N126W TO 11N135W TO BEYOND 
09N140W. SCATTERED MODERATE CONVECTION IS WITHIN 120 NM S OF 
TROUGH BETWEEN 80W AND 83W...AND WITHIN 90 NM N OF TROUGH 
BETWEEN 89W AND 93W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION CAN BE FOUND FROM 06N TO 10N BETWEEN 122W AND 130W... 
AND FROM 09N TO 13N W OF 130W.

...DISCUSSION...
ALOFT...A TROUGH/RIDGE PATTERN DOMINATES THE FORECAST REGION. AN 
UPPER ANTICYCLONE CENTERED NEAR 14N121W EXTENDS A RIDGE NE INTO 
THE SW CONUS. THE ANTICYCLONIC FLOW COVERS MOST OF BASIN BETWEEN 
100W AND 130W. BROAD UPPER LEVEL EQUATORIAL CYCLONE TO THE S OF 
ANTICYCLONE IS NOW LOCATED NEAR 02N119W. A CUT-OFF LOW IS 
SPINNING NEAR 33N137W. AN UPPER LEVEL TROUGH EXTENDS FROM THE 
LOW TO BEYOND 21N141W. THIS TROUGH SUPPORTS A COLD FRONT 
CURRENTLY MOVING ACROSS THE NW CORNER OF THE FORECAST AREA. 
STRONG SWLY FLOW OF 90-120 KT ASSOCIATED WITH A SUBTROPICAL JET 
ON THE SE PERIPHERY OF THE LOW IS AFFECTING THE NW PORTION OF 
THE FORECAST REGION. THESE WINDS ARE TRANSPORTING ABUNDANT 
MID/UPPER LEVEL MOISTURE FROM THE TROPICS INTO THE FORECAST 
WATERS. A WIDE BAND OF TRANSVERSE HIGH CLOUDS IS ASSOCIATED WITH 
THESE STRONG WINDS.  

AT THE SURFACE...LOW PRES 1009 MB IS CENTERED N OF THE AREA NEAR 
32N136W. A COLD FRONT EXTENDS FROM LOW CENTER ACROSS THE NW 
PORTION OF THE FORECAST AREA TO BEYOND 24N140W. WEAK HIGH 
PRESSURE 1019 MB IS LOCATED OVER THE N WATERS NEAR 29N125W WITH 
A RIDGE EXTENDING SE TO NEAR 20N120W. THE PRESSURE GRADIENT 
BETWEEN THESE FEATURES IS PRODUCING FRESH TO STRONG S TO SW 
WINDS WITHIN 120 NM E OF THE FRONT. THE FRONT WILL CONTINUE TO 
SHIFT EASTWARD THROUGH THE NEXT COUPLE OF DAYS...REACHING FROM 
30N128W TO BEYOND 21N138W BY FRI AFTERNOON. A SMALL AREA OF 
FRESH TO STRONG TRADEWINDS PREVAILS FROM 12N TO 18N W OF 130W 
WITH SEAS TO 11 FT. THESE WINDS WILL DECREASE IN AREAL COVERAGE 
AND DIMINISH TO 20 KT OR LESS BY FRI WITH SEAS SLOWLY SUBSIDING 
THROUGH THAT TIME. 

GAP WINDS...
NORTHERLY FLOW BEHIND A STATIONARY FRONT IN THE GULF OF MEXICO 
IS FUNNELING THROUGH THE CHIVELA PASS INTO THE GULF OF 
TEHUANTEPEC. THIS FLOW IS PRODUCING GALE FORCE WINDS OVER THE 
GULF OF TEHUANTEPEC. WINDS WILL VEER ACROSS THE GULF OF MEXICO 
OVER THE NEXT 24 HOURS. THIS WILL DECREASE THE WINDS FUNNELING 
INTO THE GULF OF TEHUANTEPEC WHICH WILL DIMINISH WINDS BELOW 
GALE FORCE BY THU AFTERNOON. 

FRESH TO STRONG WINDS OVER THE SW CARIBBEAN ARE FUNNELING 
THROUGH THE GAP IN TOPOGRAPHY OVER CENTRAL AMERICA. THIS IS 
PRODUCING FRESH TO STRONG WINDS OVER THE GULF OF PAPAGAYO. THE 
WINDS ARE PEAKING DURING THE LATE NIGHT AND EARLY MORNING HOURS 
WITH THE ADDED COMPONENT OF NOCTURNALLY DRIVEN DRAINAGE FLOW. 

$$
GR