000
AXPZ20 KNHC 251519
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED APR 26 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N77W 10N90W 7N100W 7N120W 4N140W. 
SCATTERED MODERATE CONVECTION N OF 5N BETWEEN 78W-86W. SCATTERED 
MODERATE WITHIN 120 NM OF AXIS BETWEEN 104W-114W...AND BETWEEN 
117W-139W.

...DISCUSSION...

SUBTROPICAL PACIFIC...
A FAST-MOVING PROGRESSIVE PATTERN IS IN PLACE N OF THE AREA AS A 
SERIES OF STORM SYSTEMS MOVES INTO THE U.S. PACIFIC 
NORTHWEST...OR AT LEAST BRUSHES BY BEFORE MOVING NE TOWARDS 
ALASKA. THIS HAS ISOLATED THE FLOW OVER THE SUBTROPICAL PACIFIC 
LEAVING A CUT-OFF LOW/TROUGH EXTENDING FROM 30N128W TO 20N137W 
AND ANOTHER CYCLONIC SHEAR AXIS ACROSS THE FAR NW PORTION FROM 
30N138W TO 29N140W. A 90 KT UPPER LEVEL JET LIES E OF THE 
CUT-OFF TROUGH AND IS DRAWING TROPICAL MOISTURE NE THEN E 
TOWARDS THE MEXICAN COAST. A FAIRLY STRONG SURFACE RIDGE IS IN 
CONTROL WITH THE USUAL STRATOCUMULUS FIELD W OF 118W.

TROPICAL PACIFIC...
A BROAD-SCALE UPPER RIDGE LIES ACROSS THE TROPICS CENTERED ALONG 
114W WITH THE AFOREMENTIONED SUBTROPICAL JET EXTENDING FROM THE 
BAJA PENINSULA TO THE SE ALONG THE MEXICAN PACIFIC COAST TO 
ACAPULCO. A WIDE AREA OF CIRRUS BETWEEN 110W-130W COVERS 
DOMINATES THE REGION AS OUTFLOW BLOWS N AND NE OF THE ITCZ. THE 
UPPER FLOW OVER THE E PART OF THE TROPICAL PACIFIC IS MAINLY 
VARIABLE BUT GENERALLY LIES ON THE ERN PERIPHERY OF THE PACIFIC 
RIDGE. THE NWLY FLOW COMING FROM MEXICO IS ADVECTING DRIER AIR 
OVER THE REGION...NOTED BY MODERATE SUBSIDENCE BETWEEN 85W-100W. 
A FEW CONVECTIVE CLUSTERS HAVE FORMED S OF THE PANAMA AND COSTA 
RICA COASTS WHERE LOW-LEVEL CONVERGENCE ALONG THE ITCZ IS 
STRONGEST...AND WHERE THERE IS SOME UPPER LEVEL DIFFLUENCE FROM 
A WEAK JET RUNNING ACROSS THE SRN CARIBBEAN.

$$
BERG