000
AXPZ20 KNHC 190247
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC MON APR 19 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0245 UTC.

...ITCZ...
AXIS ALONG 08N81W TO 05N98W TO 06N110W TO 05N120W TO 08N130W TO 
04140W.  ISOLATED MODERATE CONVECTION WITHIN 90 NM S OF AXIS 
FROM 85W-88W.  ISOLATED MODERATE CONVECTION WITHIN 150 NM S OF 
AXIS FROM 105W-120W.

...DISCUSSION...
SHORT WAVE TROUGH AT 29N125W JUST SE OF DEEP LAYER CYCLONIC 
VORTEX AT 30N127W CARRIES 115 KT JET STREAM AROUND ITS BASE AND 
PROMPTING DIFFLUENT FLOW ALOFT.  THIS IN TURN ENHANCES 
CONVECTION WITHIN 180 NM NE QUADRANT OF VORTEX.  UPPER LEVEL 
TROUGH EXTEND SW FROM VORTEX TO 19N140W WITH VERY DRY AIR MASS 
WITHIN 240 NM W OF AXIS DUE TO STRONG SUBSIDENCE.  VORTEX WELL 
STACKED ABOVE SURFACE LOW PRES 1009 MB BRINGING COLD FRONT DEEP 
INTO E PAC BUT WITH DIMINISHING SURFACE WINDS.  SWELLS FOLLOW 
FRONT WITH 12-14 FT SEAS SPREADING AS FAR S AS 05N.  COLD FRONT 
EFFECTIVELY DIMINISHES NE TRADES BUT REESTABLISHES THEM AGAIN 
ONCE FRONT MOVES E BY END OF FORECAST PERIOD.

SE OF VORTEX...BROAD ANTICYCLONE AT 07N116W WITH HIGHLY 
AMPLIFIED RIDGE EXTEND ITS GRIP TO 95W BRINGING FAIRLY DRY AIR 
MASS S OF 22N E OF 110W.  RIDGE CONFINES SWATH OF ABUNDANT 
TROPICAL MOISTURE ADVECTED NE TOWARDS NORTHERN  BAJA CALIFORNIA 
PENINSULA BUT WITH LITTLE UPLIFT MECHANISM TO PROMPT RAINFALL 
EVENT AS HIGH PRES DOMINATES MOST OF BASIN.  DOWNSTREAM...SHARP  
UPPER LEVEL TROUGH BRINGS MINOR AREA OF MODERATE DIFFLUENT FLOW 
ENHANCING ISOLATED MODERATE CONVECTION ALONG ITCZ FROM 85W-88W.  

ELSEWHERE AT THE SURFACE...
WEAK SURFACE HIGH PRES 1014 MB AT 23N117W MAINTAIN LID OVER 
CLOUD VERTICAL DEVELOPMENT WITH ONLY ISOLATED CONVECTION ALONG 
ITCZ W OF 105W.  LATEST MODEL GUIDANCE SOLUTIONS DISSIPATE HIGH 
PRES WHICH IS REPLACED BY MUCH STRONGER ONE...1028 MB...MOVING 
IN FROM THE NW.  AS HIGH PRES REBUILDS...FRESH NW TO N WINDS 
MOVE ALONG NW COAST OF BAJA CALIFORNIA AND SPREAD S...EVENTUALLY 
ALSO MOVING INTO GULF OF CALIFORNIA BEYOND FORECAST PERIOD.  

$$
WALLY BARNES