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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 061540
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL 
1605 UTC FRI DEC 6 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.

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

THE MONSOON TROUGH EXTENDS FROM 09N83W TO 06N99W THEN ITCZ TO 
08N117W TO 09N129W TO 07N140W. SCATTERED MODERATE CONVECTION N 
OF 05N E OF 83W.

...DISCUSSION... 

A MID/UPPER LEVEL SHORT WAVE TROUGH N OF 25N ALONG 125W-130W 
WILL MIGRATE E ACROSS NORTHERN BAJA THROUGH SAT. 1028 MB HIGH 
PRES CENTERED NEAR 36N135W WILL FOLLOW BEHIND THE SHORT WAVE 
TROUGH AND SHIFT SE TO 31N130W BY SAT NIGHT. AN EARLIER ASCAT 
PASS SHOWED AN AREA OF 20-25 KT TRADE WINDS FROM 15N TO 24N W OF 
125W...BETWEEN THE HIGH AND LOWER PRES ASSOCIATED WITH THE ITCZ. 
THIS AREA OF WINDS WILL SHIFT S OF 20N W OF 120W THROUGH SAT 
NIGHT...WITH SEAS REACHING 9-10 FT. 

TIGHTENING PRES GRADIENT BETWEEN THE HIGH AND DEEPENING LOW PRES 
OVER THE SW UNITED STATES WILL ENHANCE NW TO N WINDS W OF THE 
NORTHERN COAST OF BAJA SAT THROUGH SUN BEHIND A WEAK COLD FRONT 
MOVING THROUGH NORTHERN BAJA. 

FARTHER E...SCATTERED SHOWERS AND TSTMS PERSIST S OF PANAMA 
WHERE LIGHT SW FLOW IS CONVERGING INTO THE MONSOON TROUGH. 

GAP WINDS... 

GULF OF TEHUANTEPEC...A COLD FRONT WILL MOVE ACROSS THE WEST 
PART OF THE GULF OF MEXICO THROUGH SAT. THE FRONT WILL STALL 
OVER THE WESTERN BAY OF CAMPECHE SAT AS THE UPPER SUPPORT FOR 
THE FRONT LIFTS OUT. DENSE COLD AIR BEHIND THE FRONT WILL FUNNEL 
THROUGH THE CHIVELA PASS INTO THE GULF OF TEHUANTEPEC WITH WINDS 
INCREASING TO 20-25 KT BY SAT AFTERNOON. AS THE PUSH BEHIND THE 
FRONT DIMINISHES WHILE THE FRONT STALLS...IT IS EXPECTED TO BE A 
BRIEF LOW-SCALE EVENT WITH WINDS BELOW GALE FORCE. HOWEVER...THE 
ADDED COMPONENT OF NOCTURNAL DRAINAGE FLOW WILL ALLOW WINDS TO 
APPROACH GALE FORCE LATE SAT NIGHT AND EARLY SUN MORNING...THEN 
DIMINISH BELOW 25 KT SUN AFTERNOON. LOOKING AHEAD...A STRONGER 
GAP WIND EVENT IS LIKELY NEXT WEEK WITH GALE CONDITIONS POSSIBLE 
BY EARLY WED. 

GULF OF PAPAGAYO...WINDS ARE EXPECTED TO PULSE AT TIMES GREATER 
THAN 20 KT DURING THE OVERNIGHT AND EARLY MORNING HOURS DURING 
THE NEXT COUPLE OF DAYS.

$$
MUNDELL