000
AXPZ20 KNHC 192214
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON JAN 19 2009

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 
2045 UTC.

...ITCZ...
AXIS ALONG INTERTROPICAL CONVERGENCE ZONE...05N77W TO 02N82W TO 
04N97W TO 07N118W TO 04N127W TO 06N140W.  ISOLATED MODERATE 
CONVECTION WAS OCCURRING WITHIN 60 NM OF AXIS BETWEEN 94W AND 
103W. SCATTERED MODERATE CONVECTION WAS OCCURRING WITHIN 90 NM 
OF AXIS BETWEEN 108W AND 123W. SCATTERED TO NUMEROUS MODERATE 
CONVECTION WITH ISOLATED DEEP CONVECTION WAS OCCURRING FROM 10N 
TO 19N BETWEEN 106W AND 118W. ISOLATED MODERATE CONVECTION WAS 
OCCURRING FROM 19N TO 24N BETWEEN 108W AND 113W. ISOLATED 
MODERATE CONVECTION WAS WEAKENING WITHIN 180 NM E SEMICIRCLE OF 
1013 MB LOW.

...DISCUSSION...
MID TO UPPER LEVEL LARGE AMPLITUDE TROUGH FROM 32N123W TO 
CYCLONIC VORTEX AT 10N119W TO 05N120W IS HELPING TO MAINTAIN 
VERY DRY MID LEVEL AIR W OF AXIS.  ANTICYCLONIC SHEAR EAST OF 
TROUGH CONTINUES TO PRODUCE DIFFLUENT FLOW ALOFT BETWEEN 120W 
AND 110W...WHERE ABUNDANT TROPICAL MOISTURE CONTINUES TO BE 
ADVECTED NWD TOWARD AND INTO EXTREME SRN BAJA CALIFORNIA. 
NUMEROUS CONVECTION ACROSS THIS AREA HAS DIMINISHED N OF 16N 
DURING THE PAST FEW HOURS...BUT REMAINS ACTIVE BETWEEN 16N AND 
THE ITCZ. UPPER TROUGH WILL BEGIN TO BE NUDGED VERY SLOWLY EWD 
NEXT 12-24 HORS AS SHORT WAVE AND FRONTAL SYSTEM TO THE NW 
APPROACH THE AREA...AND UPSTREAM RIDGE BEGINS TO WEAKEN AND 
SHIFT SE. AFTER 48 HOURS THE HIGH AMPLITUDE TROUGH WILL DRIFT 
EAST TO 114W AS THE SHORT WAVE MOVES INTO W COAST OF U.S.
MID TO UPPER LEVEL MOISTURE CONTINUES TO BE ADVECTED NE INTO 
BAJA CALIFORNIA AND WRN MEXICO...WITH SOME WEAK TO MODERATE 
CONVECTION AFFECTING SRN BAJA. 

WEAKENING COLD FRONT FROM 30N133W TO 18N140W WILL MERGE WITH 
SURFACE TROUGH ALONG 127W AND REMNANTS OF SLOWLY WEAKENING 
SURFACE LOW NOW AT 19N129W...AND STALL ALONG 123W S OF 22N ON 
WED. NW SWELL GENERATED BEHIND THIS FRONT HAS AFFECTED MOST OF 
THE AREA W OF 110W...WITH SEAS IN EXCESS OF 8 FT...RANGING TO 
NEAR 18 FT BEHIND THE FRONT IN EXTREME NW PORTIONS OF AREA.  A 
1022 MB HIGH OFF OF SOUTHERN CALIFORNIA COAST HAS RIDGE 
EXTENDING TO 16N115W...HELPING TO PRODUCE 20 KT NW TO N WINDS 
FROM SRN GULF OF CALIFORNIA TO 18N.

GULF OF TEHUANTEPEC WINDS HAVE DIMINISHED TO AROUND 20 KT AND 
WILL WEAKEN SLIGHTLY WITHIN 24 HRS ONLY TO RECOVER BY 48 HRS AND 
REACH GALE FORCE BEYOND FORECAST PERIOD.  GULF OF PAPAGAYO WIND 
IS EXPECTED TO HOLD WITH LITTLE CHANGE THROUGH 36 HRS THEN 
INCREASE 20 TO 25 KT BY 48 HRS.

$$
STRIPLING