000
AXPZ20 KNHC 132133
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE APR 13 2010

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2030 UTC.

...ITCZ...

AXIS EXTENDS ALONG FROM 05N78W TO 07N89W TO 05N94W TO 10N109W TO 
07N117W TO 09N124W TO 05N140W. SCATTERED MODERATE/ISOLATED 
STRONG CONVECTION IS FROM 02N TO 06N BETWEEN 90W TO 94W...FROM 
05N TO 07N BETWEEN 97W TO 100W...AND WITHIN 90 NM EITHER SIDE OF 
THE ITCZ FROM 116W-122W. 

...DISCUSSION...
E OF 105W...
A SURFACE TROUGH EXTENDS FROM 9N86W THROUGH A 1008 MB LOW 
CENTERED NEAR 07N88W TO 04N89W. TWO UPPER RIDGES COVER TROPICAL 
ATLC...ONE EXTENDING FROM OVER SOUTH AMERICA ALONG 7N TO 90W AND 
THE SECOND ANCHORED NEAR 7N102W. BOTH UPPER RIDGES ARE ENHANCING 
THE CLUSTERS OF SCATTERED MODERATE/STRONG CONVECTION THAT COVERS 
THE AREA FROM 02N-10N BETWEEN 83W-90W. 

W OF 105W...
AN UPPER HIGH IS NEAR 15N116W WITH A RIDGE EXTENDING NE TO OVER 
NW MEXICO NEAR 29N110W WITH AN UPPER TROUGH EXTENDING FROM OVER 
NORTHERN PLAIN STATES THROUGH A SERIES OF UPPER LOWS N AND W OF 
THE REGION. A BAND OF STRONG SUBSIDENCE AND DRY STABLE AIR ALOFT 
IS WITHIN 175/225 NM OF LINE FROM 22N140W TO OVER THE N BAJA 
PENINSULA NEAR 30N116W. UPPER DIFFLUENCE TO THE S OF THIS DRY 
AIR IS ENHANCING CONVECTION ALONG THE ITCZ BETWEEN 116W AND 
122W. AT THE SURFACE...A SURFACE TROUGH EXTENDS OVER NW MEXICO 
FROM THE DESERT SW TO THE BAJA PENINSULA NEAR 28N114W BECOMING A 
SHEAR AXIS ALONG 25N75W TO 27N134W. A SURFACE RIDGE BRIDGES THIS 
SHEAR AXIS EXTENDING THROUGH 32N132W TO 18N112W. 

NE TRADES AT 15 TO 20 KT GENERALLY COVER THE AREA FROM 10N TO 
20N W OF 120W. THE ASSOCIATED NE SWELL IS MIXING WITH SW SWELL 
THAT HAS BEEN PROPAGATING N ACROSS THE THE AREA AND IS NOTED AS 
FAR N AS THE CENTRAL BAJA PENINSULA. THE SOUTHERLY SWELL IS ALSO 
MIXING WITH NW SWELL PROPAGATING SOUTHEASTWARD  IN THE WAKE OF 
THE COLD FRONT...GENERALLY OVER THE WATERS N OF 10N W OF 115W.

GAP WINDS...
GULF 0F TEHUANTEPEC...NORTHERLY 15 KT DRAINAGE WINDS ARE  
EXPECTED TO DEVELOP BRIEFLY AGAIN THU MORNING OVER THE WATERS N 
OF 15N BETWEEN 94W AND 96W DIMINISHING BY FRI.

GULF OF PAPAGAYO...NE TRADES TRADES OVER THE W CARIBBEAN SEA 
WILL DIMINISH SOME ON WED WITH THE PERSISTENT 20 KT NE WINDS 
THAT HAVE BEEN FUNNELING THROUGH THE GULF OF PAPAGAYO TO 
DIMINISH BELOW 20 KT BY WED AFTERNOON.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
WALLACE