000
AXPZ20 KNHC 042149
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE APR 04 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 2145 UTC.

...ITCZ...
ITCZ AXIS 3N77W 5N84W 4N100W 7N117W 3N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WITHIN 60 NM EITHER SIDE OF LINE 
6N84W 4N90W 4N95W AND WITHIN 30 NM EITHER SIDE OF LINE 9N106W 
9N113W 7N122W 10N126W.

...DISCUSSION...
THE NE PAC IS DOMINATED BY A LONGWAVE TROUGH WITH AN EMBEDDED A 
DEEP LAYERED CYCLONE NEAR 36N126W NOW SHIFTING NE WITH TIME. A 
SHORTWAVE TROUGH EXTENDS SW INTO THE DISCUSSION AREA ALONG 
32N124W 20N140W. VERY DRY UPPER AIR IS INDICATED W OF LINE 
30N117W 22N127W 18N140W. 

AN UPPER CUTOFF CYCLONE IS LOSING IDENTITY NEAR 1N122W. AN UPPER 
ANTICYCLONE IS NEAR 6N104W WITH A RIDGE EXTENDING N ALONG 
22N107W TO BEYOND 40N102W. TO THE E OF THE RIDGE ANOTHER 
SHORTWAVE TROUGH HAS MOVED OFF THE E COAST OF THE CONUS WITH A 
TROUGH EXTENDING SW ALONG 32N78W 21N87W. A BAND OF DRY UPPER AIR 
IS NOTED WITHIN 90 NM EITHER SIDE OF LINE 30N70W TO 22N79W WHERE 
IT WIDENS TO 300 NM EITHER SIDE OF POINTS 18N88W 21N105W.

UPPER DIFFLUENCE IS ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 
112W AND 128W. DEBRIS MOISTURE FROM THIS CONVECTION EVAPORATES 
IN VERY DRY UPPER AIR THAT ACCOMPANIES THE SHORTWAVE DESCRIBED 
ABOVE. A MORE SIGNIFICANT MOISTURE PLUME ENTERS THE DISCUSSION 
AREA WITHIN 420 NM EITHER SIDE OF LINE 10N140W THEN NARROWS TO 
WITHIN 240 NM EITHER SIDE OF POINTS 23N118W TO BEYOND 32N112W. 
OTHERWISE DRY UPPER AIR DOMINATES THE DISCUSSION AREA N OF THE 
ITCZ E OF 104W.

AT THE SURFACE...A SERIES OF FRONTAL BOUNDARIES HAVE NEARLY 
MERGED AND ARE LOSING IDENTITY ALONG 30N120W 22N125W WITH A 
RIDGE BEGINNING TO BRIDGE THE REMNANTS ALONG 28N140W 17N108W.

GULF OF PAPAGAYO...LATEST SSMI DATA AND QSCAT WINDS INDICATE NE 
WINDS 20 KT WITHIN 60 NM EITHER SIDE LINE 9N92W 11N86W. THESE 
GAP WINDS ARE EXPECTED TO FLUCTUATE TO 20 KT THROUGH 24 HOURS.  
HIGH PRES IN THE GULF OF MEXICO BRIDGED THROUGH THE ISTHMUS OF 
TEHUANTEPEC THIS MORNING AT 20-25 KT. THESE N WINDS SHOULD 
DISSIPATE TONIGHT AS THE LOW LEVEL FLOW BECOMES SE IN THE BAY OF 
CAMPECHE.

$$
NELSON