000
AXPZ20 KNHC 012158
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT NOV 01 2008

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...ITCZ...

THE AXIS OF THE INTERTROPICAL CONVERGENCE ZONE IS BETWEEN 08N84W 
TO 07N96W TO 08N114W TO 07N125W TO 08N140W. SCATTERED MODERATE 
CONVECTION LIES WITHIN 90 NM OF THE AXIS E OF 93W. SCATTERED 
MODERATE WITH ISOLATED STRONG CONVECTION LIES WITHIN 150 NM S OF 
AXIS FROM 119W TO 122W.

...DISCUSSION...

THE SURFACE LOW PRESSURE SYSTEM NEAR 07N104W IS BECOMING BETTER 
ORGANIZED.  SCATTERED MODERATE WITH ISOLATED STRONG CONVECTION 
CAN BE FOUND WITHIN 120 NM OF THE CENTER EXCEPT OUT TO 210 NM IN 
THE NE QUADRANT.  THIS SYSTEM...WHICH WAS LIKELY SPURRED BY THE 
ATMOSPHERIC VORTICITY FROM THE LOW TO MID LEVEL JET THROUGH THE 
GULF OF PAPAGAYO...WAS ENHANCED BY ADDED VORTICITY SUPPLIED BY 
THE JET THROUGH THE GULF OF TEHUANTEPEC. THE QSCAT PASS FROM 
1246 UTC REVEALS A REGION OF 20 TO 25 KT WINDS EXTENDS OUT 270 
NM FROM THE CENTER IN THE EASTERN SEMICIRCLE.  CONTINUED 
GENERATION OF DEEP CONVECTION WITH THE SYSTEM WILL HAVE TO 
BATTLE 25 TO 40 KT E TO NE SHEAR ALOFT.

THE STRONG PRESSURE GRADIENT THAT HAS BEEN PRESENT OVER CENTRAL 
AMERICA FOR SEVERAL DAYS IS FINALLY SHOWING SOME SIGNS OF 
RELAXATION...BUT WINDS IN THE GULF OF TEHAUNTEPEC ARE STILL 
EXPECTED TO REMAIN GALE FORCE THROUGH SAT NIGHT/SUN MORNING. A 
QSCAT PASS FROM 1250 UTC SUPPORTS THE CURRENT GALE WARNING N OF 
14N INTO THE GULF OF TEHAUNTEPEC.  AT THE SAME TIME...WINDS 
EXPECTED TO FALL BELOW 20 KT AND SEAS TO 8 FT IN THE GULF OF 
PAPAGAYO.

A BROAD MID TO UPPER LEVEL TROUGH HAS BEEN OVER THE N EASTERN 
PACIFIC FOR THE LAST SEVERAL DAYS IS BRINGING NW SWELL TO TO 
MUCH OF THE REGION W OF 120W.  A REINFORCING SHOT TO THIS BROAD 
TROUGH...IN THE FORM OF A COLD FRONT AT THE SURFACE...IS OVER NW 
WATERS AND IS HELPING TO CARRY THE BROAD TROUGH EASTWARD.  
MEANWHILE...THE UPPER LEVEL ANTICYCLONE S OF THE BAJA PENINSULA 
NEAR 15N120W IS PASSING WESTWARD TO THE SOUTH OF THE 
TROUGH...LIMITING THE ENCROACHMENT OF THE TROUGH TO THE SOUTH.  
THE SURFACE COLD FRONT TO DISSIPATE BY SUN...BUT LEAVE ELEVATED 
SEAS GENERALLY IN THE 8 TO 12 FT RANGE IN NW WATERS PRIMARILY N 
OF 15N AND W OF 125W ON SUN.  THE EASTERN PROGRESS OF THE COLD 
FRONT OVER N WATERS WILL HELP INCREASE THE PRESSURE GRADIENT IN 
THE VICINITY OF BAJA CALIFORNIA WHERE WINDS ARE EXPECTED TO BE 
IN THE 20 RANGE THROUGH THE WEEKEND.

$$
SCHAUER CLARK