000
AXPZ20 KNHC 200321
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JUN 20 2008

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0315 UTC.

...TROPICAL WAVES...
TROPICAL WAVE FROM 8N TO 17N ALONG 100W MOVING W 10 KT. 
SCATTERED WEAKENING MODERATE CONVECTION IS OVER THE S PORTION OF 
THE WAVE GENERALLY S OF 12N TO THE ITCZ. INFRARED SATELLITE 
IMAGERY INDICATES SOME MID LEVEL TURNING OF THE CLOUD ELEMENTS 
IN THE VICINITY OF 8N100W...HOWEVER THIS TURNING IS NOT AS WELL
DEFINED AS SIX HOURS AGO. 

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE 08N78W TO 13N108W TO 12N120W TO 
07N140W. SCATTERED MODERATE TO STRONG WITHIN 180-210 NM S OF 
AXIS AND 120 NM N OF AXIS BETWEEN 106W AND 117W. SCATTERED 
MODERATE ISOLATED STRONG FROM 03N TO 11N BETWEEN 90W AND 
95W...AND FROM 06N TO 12N BETWEEN 100W AND 103W.

...DISCUSSION...
SHEARING POSITIVELY TILTED UPPER LEVEL TROUGH IS JUST TO THE NW 
OF THE AREA ALONG 32N135W TO 23N150W. THIS TROUGH IS MERGING 
INTO AN AREA OF GENERAL TROUGHINESS OVER THE NW PORTION NW OF A 
LINE FROM 10N140W THROUGH 30N125W. A PATCH OF STRONG MID LEVEL 
SUBSIDENCE WAS NOTED FROM 20N TO 30N W OF 127W. A 55-75 KT WIND 
MAXIMA JUST SE OF THE TROUGH NOTED ABOVE IS ADVECTING MID AND 
UPPER LEVEL TROPICAL ITCZ MOISTURE NE TOWARD S CALIFORNIA 
AND THE DESERT SW CONUS. BROAD MID/UPPER LEVEL RIDGE EXTENDS 
FROM SE ARIZONA THROUGH AN ANTICYCLONE OVER CENTRAL BAJA 
CALIFORNIA NEAR 28N112W TO ANOTHER ANTICYCLONE CENTERED NEAR 
19N118W. ANOTHER SMALLER ANTICYCLONE WAS CENTERED NEAR 14N106W. 
RATHER SHARP MID TO UPPER LEVEL TROUGH EXTENDS FROM THE GULF OF 
MEXICO ACROSS CENTRAL MEXICO TO A CYCLONIC CIRCULATION NEAR 
18N111W WHICH WAS MOVING WWD BETWEEN THE FIRST AND LAST 
ANTICYCLONES NOTED ABOVE. THE FLOW S OF 15N BETWEEN 98W AND 
115W WAS DIFLUENT IN NATURE AND WAS ENHANCING CONVECTION ALONG 
THE ITCZ AND IN THE VICINITY OF THE TROPICAL WAVE ALONG 100W.

SURFACE TROUGH IS ANALYZED ALONG THE ITCZ ALONG 110W WITH A WEAK
1011 MB LOW PRES NEAR 13N109W. SCATTERED MODERATE TO 
STRONG CONVECTION IS ASSOCIATED WITH THE TROUGH AND LOW PRES.

ANOTHER SURFACE LOW PRES 1012 MB WAS LOCATED WITHIN THE ITCZ AND
WAS CENTERED NEAR 12N121W. NO SIGNIFICANT CONVECTION IS 
ASSOCIATED WITH THIS LOW PRES. OTHERWISE HIGH PRES COVERS THE 
AREA N OF 14N W OF 110W.

MODERATE TO FRESH TRADE WINDS IN THE CARIBBEAN SEA ARE EXPECTED
TO BLOW ACROSS CENTRAL AMERICA INTO THE GULF OF PAPAGAYO WITHIN 
18 HOURS OR SO WITH 20 KT WINDS EXPECTED. THESE WINDS ARE 
EXPECTED TO PERSIST THROUGH 48 HOURS WITH SEAS BUILDING TO 8 OR 
9 FT BY THEN.  

$$
COBB