000
AXPZ20 KNHC 160317
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN MAY 16 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 
0245 UTC.

...TROPICAL WAVES...

A WEAK TROPICAL WAVE IS ALONG 95W FROM 04N-10N MOVING W AT 10 
KT. NO SIGNIFICANT CONVECTION WAS NOTED DUE TO INCREASING N-NE 
SHEAR ALOFT. THE WAVE IS NOT EXPECTED TO DEVELOP ANY CYCLONIC 
ORGANIZATION WITHIN NEXT 24-48 HOURS.

...ITCZ...

ITCZ AXIS IS ALONG 07N78W TO 07N94W TO 09N104W TO 08N111W TO 
09N116W TO 08N140W. SCATTERED MODERATE CONVECTION IS WITHIN 180
NM S OF THE AXIS BETWEEN 90W AND 92W...WITHIN 120 NM N OF THE 
AXIS BETWEEN 110W AND 113W...AND WITHIN 60 NM N OF THE AXIS 
BETWEEN 123W AND 125W...AND W OF 137W.

...DISCUSSION...

AN UPPER LEVEL TROUGH EXTENDS FROM 32N107W TO 22N112W. MID TO 
UPPER LEVEL MOISTURE IS NOTED W OF THE TROUGH AXIS OVER NW 
MEXICO INCLUDING THE NORTHERN BAJA PENINSULA. AN UPPER RIDGE 
EXTENDS FROM 32N119W TO 25N117W. VERY DRY AIR IS NOTED UNDER 
THIS RIDGE AND S OF THE RIDGE WHERE A MAINLY ZONAL FLOW EXISTS 
FROM 21N TO 25N. ANOTHER UPPER LEVEL TROUGH IS TO THE W 
EXTENDING FROM 32N130W TO 23N140W WITH MID TO UPPER LEVEL 
MOISTURE ARRIVING BEHIND THE TROUGH AXIS. 

AN UPPER ANTICYCLONE IS CENTERED NEAR 09N107W WITH A RIDGE AXIS 
EXTENDING ALONG 09N ACROSS THE ENTIRE BASIN. A JETSTREAM WITH 
CORE WIND SPEEDS OF 70-90 KT ENTERS THE AREA NEAR 17N140W AND 
EXTENDS TO THE NE-E TO NEAR 21N105W AND ACROSS CENTRAL MEXICO 
WITH MID TO UPPER LEVEL MOISTURE BEING ADVECTED FROM THE DEEP 
TROPICS S OF THE HAWAIIAN ISLANDS TO THE NE-E AROUND THE 
NORTHERN PERIPHERY OF THE ANTICYCLONE AND RIDGE. MODERATE UPPER 
LEVEL DIFFLUENCE ON THE S SIDE OF THE ANTICYCLONE IS HELPING TO 
ENHANCE SPORADIC CONVECTION ALONG THE ITCZ W OF 105W AND E OF 
92W.

A SURFACE TROUGH EXTENDS ALONG 105W FROM 06.5N TO 11.5N. THIS 
TROUGH IS THE REMNANTS OF AN AREA OF LOW PRES WHICH ENCOUNTERED 
INCREASING WESTERLY SHEAR ALOFT. NO SIGNIFICANT CONVECTION IS 
NOTED WITH THIS FEATURE.

ELSEWHERE AT THE SURFACE...1024 MB HIGH PRES IS CENTERED NEAR 
29N138W WITH A BROAD RIDGE AXIS EXTENDING FROM THE HIGH CENTER 
TO NEAR 14N107W. NE TRADES AT 20 KT ARE SW OF THE RIDGE AXIS 
FROM 10N TO 20N W OF 120W. THE STRENGTH AND AREAL COVERAGE OF 
THESE TRADES WILL DIMINISH SIGNIFICANTLY DURING THE NEXT 48 
HOURS AS THE PRES GRADIENT WEAKENS. NE SWELL GENERATED FROM THE 
TRADES IS MIXED WITH CROSS EQUATORIAL SW SWELL. THIS SW SWELL 
COVERS THE MAJORITY OF THE REMAINDER OF THE DISCUSSION AREA AND 
WILL GRADUALLY DECAY AND SUBSIDE TO LESS THAN 8 FT DURING THE 
NEXT 48 HOURS.

GAP WINDS...NE-E WINDS AT 20 KT THROUGH THE GULF OF PAPAGAYO E 
OF 89W ARE EXPECTED TO DIMINISH TO LESS THAN 20 KT IN 12 HOURS 
AS THE SOURCE OF THE STRONG WINDS IN THE WESTERN CARIBBEAN 
WEAKENS.

$$
LEWITSKY