000
AXPZ20 KNHC 190330
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED MAY 19 2010

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 
0215 UTC.

...TROPICAL WAVES...
TROPICAL WAVE FROM 03N TO 11N ALONG 92W IS MOVING W AT 15 KT 
AS AVERAGED OVER THE PAST 24 HOURS. THE WAVE REMAINS EMBEDDED 
WITHIN A FAIRLY DRY ENVIRONMENT WHICH APPEARS TO BE INHIBITING 
DEEP CONVECTION ALONG THE WAVE AXIS IN ADDITION THE SYSTEM HAS 
MOVED INTO A MORE ADVERSE UPPER LEVEL ENVIRONMENT CHARACTERIZED 
BY N TO NE SHEAR TO THE SE OF AN UPPER LEVEL ANTICYCLONE LOCATED 
NEAR THE GULF OF TEHUANTEPEC.  

TROPICAL WAVE FROM 13N121W TO 06N124W. THE WAVE WAS RELOCATED 
SIX HOURS AGO BASED ON 24-HOUR CONTINUITY...HOVMOLLER ANALYSIS 
AND AN 1806 UTC ASCAT PASS WHICH SHOWED A CLEARLY DEFINED LOW 
LEVEL CIRCULATION. THE WAVE IS EMBEDDED WITHIN AN UNFAVORABLE 
ENVIRONMENT CHARACTERIZED BY STRONG W TO SW SHEAR AND AN 
INCREASINGLY DRIER ATMOSPHERE. 

...ITCZ...
AXIS FROM 08N78W TO 08N92W TO 10N121W TO 06N132W TO 06N140W. 
SCATTERED STRONG WITHIN 90-120 NM EITHER SIDE OF AXIS BETWEEN 
96W AND 102W. SCATTERED MODERATE WITHIN 120 NM N OF AXIS BETWEEN 
106W AND 112W. 

...DISCUSSION...
WEAK UPPER LEVEL TROUGH HAS DEGENERATED INTO A SHEAR AXIS AND 
EXTENDS FROM SRN ARIZONA TO 26N121W. THE BULK OF THE ENERGY 
ASSOCIATED WITH THE FORMER TROUGH HAS LIFTED N OF THE AREA 
LEAVING MOSTLY ZONAL FLOW IN ITS WAKE. FURTHER S...A RATHER 
EXPANSIVE BUT FLATTENING UPPER LEVEL ANTICYCLONE WAS LOCATED 
JUST EAST OF THE GULF OF TEHUANTEPEC NEAR 15N92W. A BRANCH OF 
THE SUBTROPICAL JET CURVES AROUND THE PERIPHERY OF THE 
ANTICYCLONE THROUGH 17N124W ACROSS THE SRN TIP OF BAJA 
CALIFORNIA THEN TURNS EASTWARD ACROSS CENTRAL MEXICO INTO THE SW
GULF OF MEXICO. SATELLITE DERIVED WINDS INDICATED CORE 
SPEEDS OF 90-120 KT. THE JET AXIS WAS ADVECTING ABUNDANT MID TO 
UPPER LEVEL TROPICAL MOISTURE EWD ACROSS THE PACIFIC AND CENTRAL 
MEXICO.    

ELSEWHERE AT THE SURFACE...
HIGH PRESSURE RIDGE EXTENDS FROM 1 1022 MB CENTER NEAR 29N138W 
SE ALONG 24N120W TO 14N108W. THE RIDGE HAS BRIDGED EASTWARD 
ALLOWING THE WEAK COLD FRONT NOTED EARLIER TO COMPLETELY 
DISSIPATE. THIS RIDGE IS FORECAST TO STRENGTHEN OVER THE NEXT 
FEW DAYS AND ALLOW TRADES TO INCREASE IN AREAL COVERAGE 
GENERALLY FROM 08N TO 17N W OF 125W BY 36 TO 48 HOURS.  

NORTHWESTERLY WINDS OF 20 TO 25 KT WITHIN 120 NM OF THE W COAST 
OF BAJA CALIFORNIA ARE EXPECTED TO INCREASE IN AREAL COVERAGE 
AND INTENSITY AS HIGH PRESSURE BUILDS E AND LOW PRESSURE 
DEVELOPS OVER THE SW CONUS. THESE WINDS MAY DRIVE SEAS OF UP TO 
10 FT ALONG 30N BY 48 HOURS. 

CROSS EQUATORIAL LONG PERIOD SW SWELL OF UP TO 20 SECONDS AND 10 
TO 12 FT WILL SPREAD INTO THE REGION S OF 10N W OF 90W OVER THE 
NEXT 24 HOURS...AND S OF 15N AND W OF 110W BY 48 HOURS. THESE 
SWELLS MAY IMPACT SOUTH FACING BEACHES ALONG THE BAJA CALIFORNIA 
AND MEXICAN COASTLINES FRI AND INTO THE WEEKEND.  

$$
COBB