000
AXPZ20 KNHC 122210
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED APR 12 2006

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 2045 UTC.

...ITCZ...
ITCZ AXIS IS CENTERED ALONG 7N78W 5N90W 3N102W 6N120W 7N130W
3N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS 
WITHIN 90 NM EITHER SIDE OF THE AXIS BETWEEN 131W-134W...AND
ALSO WITHIN 60 NM EITHER SIDE OF THE AXIS BETWEEN 84W-87W.
SCATTERED MODERATE CONVECTION IS WITHIN 60 NM EITHER SIDE
OF AXIS W OF 138W.

...DISCUSSION...
THE NE PAC IS DOMINATED BY A LONGWAVE TROUGH WITH 2 EMBEDDED 
CYCLONES ROTATING THROUGH THE TROUGH. THE SOUTHERNMOST DEEP 
LAYERED CYCLONE IS NEAR 35N128W WITH A MEAN TROUGH AXIS S ALONG 
140W TO JUST N OF THE ITCZ. MODERATE TO STRONG SUBSIDENCE AND 
ASSOCIATED DRY SINKING AIR COVERS THE AREA WITHIN 350 NM EITHER
SIDE OF LINE 32N112W 24N127W TO 23N140W. THE DEEP CYCLONE IS
EXPECTED TO CONTINUE TO MOVE SE TO NEAR 29N126W IN ABOUT 48
HOURS THEN TURN NE INTO SOUTHERN CALIFORNIA IN 48-60 HOURS. THE 
ASSOCIATED SURFACE COLD FRONT WILL SWING SE TO ALONG 130W IN
ABOUT 18-24 HOURS THEN OVERRUN ANY REMNANTS OF A FRONTAL TROUGH 
THAT CURRENTLY IS ABOUT 360 NM E OF THIS SECONDARY BOUNDARY. THE 
NW SWELLS BEHIND THE INITIAL FRONT WILL BE REINFORCED BY LARGER 
N SWELLS THAT WILL ACCOMPANY THE SECOND FRONT.       

AN UPPER LEVEL ANTICYCLONE IS LOCATED NEAR 13N111W WITH A RIDGE 
EXTENDING SW TO A SHARP CREST AT 4N145W. A RIDGE ALSO EXTENDS NE 
ACROSS OLD MEXICO CRESTING JUST E OF THE TX COAST AT 28N95W. 
UPPER DIFFLUENCE UNDER THE RIDGE IS ENHANCING CONVECTION 
ALONG...AND JUST TO THE N OF THE ITCZ...W OF 125W. UPPER DEBRIS 
MOISTURE FROM THIS CONVECTION SPREADS N ALONG THE W PERIPHERY OF 
THE RIDGE...ROUGHLY WITHIN 240 NM EITHER SIDE OF LINE FROM 
10N125W TO 20N115W THEN NARROWS AND CONTINUES NE ACROSS OLD 
MEXICO INTO THE GULF OF MEXICO NEAR 27N100W.

A SHARP POSITIVE TILT UPPER TROUGH ACROSS THE SW ATLC EXTENDS
SW INTO THE WESTERN CARIBBEAN AND CONTINUES SW ACROSS GUATEMALA
AND HONDURAS AND INTO THE EASTERN PACIFIC TO A SMALL CYCLONE 
MOVING W 15 KT NEAR 2N107W. STRONG SUBSIDENCE AND ASSOCIATED
DRY UPPER AIR IS SEEN ON WATER VAPOR IMAGERY FROM 7N-21N AND
EAST OF 112W TO ACROSS MEXICO AND CENTRAL AMERICA.

WEAK MID-UPPER LEVEL RIDGING EXTENDS ALONG 6N E OF 95W. THE
RIDGE IS AIDING CONVECTION ALONG THE ITCZ AXIS BETWEEN 
84W-88W. DEBRIS UPPER LEVEL BLOWOFF CLOUDINESS IS BEING 
ADVECTED NE ACROSS CENTRAL AMERICA S OF NICARAGUA INTO THE 
THE EXTREME SW CARIBBEAN SEA. SIMILAR CLOUDINESS IS NOTED
ACROSS NW COLOMBIA.

GAP WINDS...GULF OF TEHUANTEPEC...MODEL GUIDANCE AGAIN 
FLUCTUATES THE NLY WINDS FROM 15-25 KT THROUGH WED NIGHT THEN 
INCREASE N FLOW THROUGH THE GAP TO GALE FORCE AT 12 UTC THU. AN 
ELY SURGE THROUGH GULF OF PAPAGAYO WILL CONTINUE THROUGH NEXT 
24-36 HOURS. 

$$
AGUIRRE