000
AXPZ20 KNHC 131512
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU NOV 13 2008

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1315 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS CAN BE FOUND ALONG A 
LINE FROM 06N75W TO 08N87W TO 06N100W TO 10N115W TO 07N140W. 
SCATTERED MODERATE ISOLATED WITH ISOLATED STRONG CONVECTION LIES 
WITHIN 60 NM N AND 120 NM S E OF 81W. SCATTERED MODERATE 
CONVECTION CAN BE FOUND WITHIN 120 NM N AND 60 NM S OF AXIS 
BETWEEN 90W AND 101W.
 
...DISCUSSION...
THE STRONG EASTERLY TRADE WINDS OVER WESTERN WATERS BETWEEN 10N 
AND 20N ARE EXPECTED TO WANE TO 20 KT OR LOWER OVER THE NEXT TWO 
DAYS AS THE SUBTROPICAL HIGH IS WEAKENED AND FORCED 
NORTHEASTWARD BY A MID LATITUDE DEEP LAYER TROUGH APPROACHING 
FAR NW WATERS BY THE END OF THE WEEKEND.  IN THE MEANTIME...THE 
STRONG NORTHERLY WINDS OVER N CENTRAL WATERS ON THE SOUTHEASTERN 
SIDE OF THE HIGH WILL ALSO WANE AND SHIFT WESTWARD OVER THE NEXT 
TWO DAYS AS TROUGHING ALONG THE W COAST OF MEXICO EXPANDS 
WESTWARD IN RESPONSE TO THE UPPER LEVEL SHEDDING AND 
RETROGRADING OF ENERGY FROM THE MID TO UPPER LEVEL TROUGH 
CURRENTLY OVER NORTHERN AND CENTRAL MEXICO.  THIS TROUGH IS 
EXPECTED TO BE OVERTAKEN BY AN AMPLIFYING MID LATITUDE TROUGH 
DIVING SOUTHWARD THROUGH THE PLAINS OVER THE WEEKEND.  ITS 
ASSOCIATED COLD FRONT WILL PUSH SOUTH THROUGH NORTHERN MEXICO 
SAT TO THE GULF OF TEHAUNTEPEC BY SUN.  HIGH PRESSURE BEHIND 
THIS COLD FRONT WILL SET UP A STRONG PRESSURE GRADIENT BOTH OVER 
THE GULF OF CALIFORNIA ON LATE FRI/EARLY SAT AND THE GULF OF 
TEHAUNTEPEC ON LATE SAT/EARLY SUN WITH WINDS IN EXCESS OF 20 KT 
EXPECTED.

IN THE TROPICS...SOUTHWESTERLY CROSS-EQUATORIAL SW SWELL COUPLED 
WITH WINDS TO 20 KT BETWEEN THE GALAPAGOS AND PANAMA WILL KEEP 
THE SEAS ELEVATE TO AROUND 8 FT FOR THE NEXT FEW DAYS.  OVER S 
CENTRAL WATERS...THE AFOREMENTIONED MID TO UPPER LEVEL ENERGY 
SHEDDING SOUTHWESTWARD FROM THE TROUGH CURRENTLY OVER MEXICO 
WILL RETROGRADE AND CLOSE OFF AN UPPER LOW OVER THE WEEKEND 
DISRUPTING THE DEEP LAYER ANTICYCLONE YIELDING LIGHT WINDS LESS 
THAN 10 KT OVER MUCH OF THE REGION S OF 20N BETWEEN 90W AND 120W 
UNTIL THE COLD FRONT PUSHES S THROUGH MEXICO SAT. FINALLY...THE 
UPPER LEVEL LOW E OF HAWAII BRINGING MID TO UPPER LEVEL MOISTURE 
NORTHEASTWARD INTO W WATERS WILL WEAKEN AND BE FORCED NORTHWARD 
INTO THE LEADING EDGE OF THE DEEP LAYER TROUGH APPROACHING NW 
WATERS AT THE END OF THE WEEKEND.  NO SIGNIFICANT PRECIPITATION 
IS ANTICIPATED AT THE SURFACE OVER FORECAST WATERS IN CONNECTION 
WITH THIS SYSTEM.

$$
SCHAUER CLARK