000
AXPZ20 KNHC 191614
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT NOV 19 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...SPECIAL FEATURE...

AN 1006 MB AREA OF LOW PRES IS EMBEDDED IN THE MONSOON TROUGH 
NEAR 10N99W MOVING W AT ABOUT 7 KT. OVERALL SYSTEM STRUCTURE 
CONTINUED TO DEVELOP WITH A WELL-DEFINED LOW JUST WEST OF THE 
DEEP CONVECTION.  THE LOW IS UNDER VERY CONDUCIVE ANTICYCLONIC 
FLOW ALOFT WITH LOW VERTICAL SHEAR...AND AS IT CONTINUES TO PULL 
FURTHER AWAY FROM DRIER AND MORE STABLE AIR FLOWING SW FROM THE 
GULF OF TEHUANTEPEC THE ENVIRONMENTAL CONDITIONS WILL CONTINUE 
TO PROVIDE IT WITH A HIGH CHANCE FOR IT TO DEVELOP INTO A 
TROPICAL CYCLONE DURING THE NEXT 24-48 HOURS. INDEED...ALL OF 
THE GLOBAL MODEL GUIDANCE SUGGESTS GENESIS AND CONTINUED 
INTENSIFICATION WITHIN THE NEXT TWO DAYS.  BECAUSE OF ITS HIGH 
LIKELIHOOD OF DEVELOPING GALE FORCE WINDS IN ABOUT 36 HOURS...A 
GALE WARNING HAS BEEN ISSUED FOR THIS SYSTEM.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
 
THE MONSOON TROUGH EXTENDS FROM NORTHERN COSTA RICA TO 10N94W TO 
LOW PRES NEAR 10N99W TO 08N117W. THE INTERTROPICAL CONVERGENCE 
ZONE AXIS THEN EXTENDS FROM 08N117W TO 10N126W THEN RESUMES FROM 
09N133W TO 08N140W. SCATTERED MODERATE ISOLATED STRONG WITHIN 60 
NM OF ITCZ BETWEEN 121W AND 126W AND AGAIN BETWEEN 133W AND 136W.

...DISCUSSION...

ELSEWHERE AT THE SURFACE...HIGH PRES OF 1032 MB NW OF THE 
DISCUSSION AREA NEAR 37N149W EXTENDS A RIDGE THROUGH 30N135W SE 
TO NEAR 22N111W. HIGH PRES COVERS THE AREA N OF ABOUT 16N AND W 
OF 118W. NW SWELLS ARE ALLOWING FOR SEAS OF 8-11 FT TO EXIST N 
OF 28N AND W OF 120W. A NEW SET OF LARGER NW SWELL WITH PEAK 
WAVE PERIODS OF 16-18 SECONDS WILL PROPAGATE INTO THE NW PORTION 
OF THE DISCUSSION WATERS STARTING BY LATE TONIGHT. A COLD FRONT 
WILL ARRIVE SUN MORNING REACHING FROM 30N126W TO 28N135W TO 
29N140W...THEN WILL WEAKEN AS IT REACHES FROM 30N116W TO 25N130W 
BY 12 UTC MON. THE NW SWELL WILL BUILD TO 13 OR 14 FT W OF FRONT 
TO 135W.

A SURFACE TROUGH IS ANALYZED ALONG THE ITCZ EXTENDING FROM 
09N131W TO 12N125W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION EXISTS WITHIN 60 NM OF TROUGH AXIS.  NO FURTHER 
TROPICAL DEVELOPMENT OF THIS SYSTEM IS ANTICIPATED.

GAP WINDS...THE PRES GRADIENT CONTINUES TO SLOWLY WEAKEN OVER 
THE GULF OF TEHUANTEPEC REGION ALTHOUGH N-NE 20-25 KT WINDS AND 
SEAS TO 9 FT PERSIST AS SEEN 1411Z ASCAT PASS. THESE WINDS AND 
SEAS WILL DIMINISH TO LESS THAN 20 KT AND LESS THAN 8 FT BY 12 
HRS. N WINDS OF 20 KT WILL THEN RESTART THROUGH THE GULF SUN 
NIGHT.

$$
AGUIRRE/LANDSEA