000
AXPZ20 KNHC 212157
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT APR 21 2007

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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...ITCZ...
ITCZ AXIS 9N80W 6N87W 6N125W  3N135W 3N140W.  SCATTERED STRONG 
WITHIN 120 NM OF 5N83W.  SCATTERED MODERATE ISOLATED STRONG 
WITHIN 120 NM OF AXIS FROM 106W TO 139W.

...DISCUSSION...
MID/UPPER LEVEL CYCLONIC CIRCULATION AT 22N126W HAS UPPER LEVEL 
TROUGH EXTEND W TO 22N140W.  MODERATE TO STRONG SUBSIDENCE 
MAINTAINS VERY DRY AIR MASS WITHIN 300 NM E OF TROUGH AXIS. 
WEAK WLY SUBTROPICAL JET CORE 95 KT S OF AXIS ADVECTING 
SIGNIFICANT AMOUNTS OF UPPER LEVEL MOISTURE AND BACKS NE AROUND 
CYCLONIC VORTEX BRINGING MOISTURE CLOSER TO BAJA CALIFORNIA AND 
NW MEXICO.  ELSEWHERE W OF 120W...BROAD UPPER LEVEL RIDGE 
MAINTAINS FAIR DIFFLUENT PATTERN ABOVE ITCZ PATRONIZING 
CONVECTION W OF 105W BUT BLOWING DEBRIS MOISTURE S AWAY FROM 
ABOVE MENTIONED MOISTURE PATH LITERALLY CUTTING OFF WATER SOURCE
...EXCEPT AS MENTIONED BELOW.

OVER ERN SECTION...UPPER RIDGE OVER COLOMBIA/SWRN CARIBBEAN 
HELPS BRING LIMITED AMOUNT OF MOISTURE INTO ITCZ MOSTLY E OF 
85W.  SOURCE SEEMS SPORADIC AND NOT EXPECTED TO BE LONG LASTING 
AS CONVECTION W OF 105W.  WEAK DEFORMATION ZONE FROM 92W-98W 
DEVOID OF ANY SIGNIFICANT DEEP CONVECTION.

AT THE SFC...STATIONARY 1025 MB HIGH PRES CENTER AT 29N137W HAS 
RIDGE EXTENDING SE TO 23N118W COVERING FORECAST WATERS N OF 16N  
W OF 116W.  PRES GRADIENT PRODUCING NE TRADES FROM 6N-23N W OF 
125W.  NW WINDS CONFINED TO NE PART FROM 23N-28N E OF 118W 
EXPECTED TO DIMINISH NEXT 36 HRS AS HIGH PRES SLOWLY MOVES E AND 
WEAKENS.

$$
WALLY BARNES