000
AXPZ20 KNHC 270925
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI APR 27 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N77W 7N96W 7N110W 9N122W 5N140W. 
SCATTERED MODERATE CONVECTION IS WITHIN 90 NM S OF AXIS BETWEEN 
84W-87W. SCATTERED SHOWERS/TSTMS FROM 12N-14N BETWEEN 88W-92W.

...DISCUSSION...

SUBTROPICS...
UPPER SWLY FLOW AHEAD OF A WEAK SHORTWAVE TROUGH CLIPS THE NW 
PORTION OF THE REGION. THIS SWLY FLOW AND DIFFLUENCE ALOFT IS 
GENERATING AND TRANSPORTING A SWATH OF MOISTURE CURRENTLY 
CONTAINED S OF 25N W OF 132W. THE UPPER FLOW THEN BECOMES 
ANTICYCLONIC AROUND AN UPPER HIGH CENTERED JUST OFF THE SRN 
CALIFORNIA COAST NEAR 34N127W. A PRONOUNCED ELONGATED TROUGH 
LIES TO THE E OF THE RIDGE EXTENDING FROM ARIZONA ACROSS NRN 
BAJA TO ABOUT 24N122W. A SWLY JET BRANCH WITH CORE WINDS NEAR 
100 KT ORIGINATES NEAR THE BASE OF THE SW U.S./BAJA TROUGH AND 
RUNS ACROSS NRN MEXICO. UPPER CONFLUENCE TO THE W OF THE JET 
AXIS IS SUPPLYING DRY STABLE AIR ALOFT BETWEEN 113W-130W. IN THE 
LOWER LEVELS...A 03Z QSCAT PASS AND SHIP OBS DEPICT THE NLY 
SURGE OFF THE CALIFORNIA/BAJA COAST WELL WITH N-NWLY WINDS 
MOSTLY NEAR 20 KT WITH A FEW 25 KT WIND VECTORS MIXED IN. THESE 
WINDS ARE FORECAST TO SLACKEN...FALLING BELOW 20 KT ON SAT 
...AS THE 1029 MB HIGH NEAR 34N134W WEAKENS IN PLACE. 

TROPICS...
THE MAIN FEATURE IN THIS REGION IS A FAIRLY LARGE UPPER HIGH 
CENTERED NEAR 10N102W. A RIDGE AXIS EXTENDS N-S ALONG 102W WITH 
ANOTHER MUCH WEAKER FAINT AXIS RUNNING W FROM THE HIGH ALONG 
10N. THE ITCZ IS MUCH QUIETER THAN RECENT DAYS WITH NO 
SIGNIFICANT CONVECTION OBSERVED ALONG THE AXIS W OF THE HIGH 
CENTER. NLY WINDS E OF THE UPPER HIGH TO 92W IS DRAWING IN DRY 
AIR IN THE MID AND UPPER LEVELS PREVENTING CLOUDS FROM ACQUIRING 
MUCH DEPTH. THERE ARE A FEW POCKETS OF SCATTERED MODERATE 
CONVECTION E OF 92W IN A DIFFLUENT ZONE BETWEEN THE EPAC AND 
CARIB RIDGES...BUT NONE OF THESE PATCHES ARE VERY WELL 
ORGANIZED. IN THE LOWER LEVELS...NELY TRADES ARE MOSTLY NEAR 20 
KT FROM 7N-24N W OF 128W. THESE TRADES ARE FORECAST TO SLACKEN 
TODAY INTO THE WEEKEND AS THE SUBTROPICAL HIGH WEAKENS IN 
RESPONSE TO AN APPROACHING FRONTAL TROUGH TO ITS W.

$$
CANGIALOSI