000
AXPZ20 KNHC 250324
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE MAY 25 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 
0230 UTC.

...TROPICAL WAVES...
TROPICAL WAVE FROM 05N-11N ALONG 125W/126W MOVING W AT 10 KT AS 
AVERAGED OVER THE PAST 24 HOURS. THE WAVE IS NOT ACCOMPANIED BY 
ANY APPRECIABLE CONVECTION. NO DEVELOPMENT IS EXPECTED AS THE 
WAVE IS APPROACHING AN AREA CHARACTERIZED BY MODERATE TO STRONG 
SHEAR.  

...ITCZ...
AXIS IS ALONG 10N86W TO 08N110W TO 09N128W TO 06N140W. SCATTERED 
MODERATE TO STRONG FROM 07N TO 10N BETWEEN 84W AND 94W. 
SCATTERED MODERATE WITHIN 90-120 NM EITHER SIDE OF AXIS BETWEEN 
109W AND 121W. 

...DISCUSSION...

A FLAT BROAD UPPER LEVEL TROUGH COVERS THE FAR N PORTION OF THE 
DISCUSSION AREA GENERALLY N OF 25N WITH A 240-300 NM WIDE RIBBON 
OF DRY AIR CUTTING THROUGH THE BASE OF THE TROUGH. THE SOUTHERN 
EDGE OF THE DRY AIR IS SITUATED TO THE N OF AN 80-100 KT 
SUBTROPICAL JET STREAM WHICH ENTERS THE AREA NEAR 20N140W AND 
CONTINUES ENE THROUGH 21N120W...THE SOUTHERN TIP OF BAJA 
CALIFORNIA AND INTO NRN MEXICO. THE JET IS ADVECTING HIGH LEVEL 
MOISTURE FROM ITCZ CONVECTION BETWEEN 120W AND 135W.   

AN UPPER LEVEL RIDGE EXTENDS FROM AN ANTICYCLONIC CIRCULATION 
NEAR 12N1118W THROUGH ANOTHER CIRCULATION CENTER NEAR 14N101W 
THEN NORTHWARD ACROSS THE FAR WRN GULF OF MEXICO TO EAST TEXAS. 
UPPER LEVEL DIFFLUENT FLOW S AND SW OF THE ANTICYCLONIC 
CIRCULATIONS IS ENHANCING CONVECTION ALONG THE ITCZ FROM 
109W-121W. UPPER LEVEL DIFFLUENT FLOW TO THE SE OF THE 
ANTICYCLONE IS ENHANCING CONVECTIVE ACTIVITY ALONG THE COAST OF 
CENTRAL AMERICA FROM EL SALVADOR TO COSTA RICA IN THE VICINITY 
OF A SURFACE TROUGH DESCRIBED BELOW. 

SURFACE RIDGE COVERS THE AREA N OF 14N W OF 110W. THE RIDGE IS 
PRODUCING A TIGHT ENOUGH PRES GRADIENT TO SUPPORT NE TO E 20-25 
KT WINDS IN AN AREA FROM 10N TO 25N W OF 125W. THE GRADIENT 
BETWEEN THE SAME RIDGE AND LOWER PRES OVER MEXICO IS PRODUCING 
20-25 KT NW WINDS ALONG THE COAST OF BAJA CALIFORNIA. THESE 
WINDS SHOULD DECREASE AND BECOME CONFINED TO WITHIN 120 NM OF 
THE BAJA CALIFORNIA COAST AS THE RIDGE WEAKENS.

THREE TROUGHS ARE ANALYZED ALONG THE ITCZ. THE MOST SIGNIFICANT 
TROUGH EXTENDS FROM 07N88W THROUGH COSTA RICA INTO THE EXTREME 
SW CARIBBEAN SEA AND IS ASSOCIATED WITH AN AREA OF DISTURBED 
WEATHER. THE LAST VISIBLE SATELLITE IMAGERY OF THE DAY FROM 
SEVERAL HOURS AGO INDICATED WELL DEFINED LOW AND MID LEVEL 
CYCLONIC TURNING OVER PORTIONS OF SOUTHERN CENTRAL AMERICA. 
SURFACE OBSERVATIONS AND LOW CLOUD MOTIONS SUGGEST A BROAD LOW 
PRESSURE AREA MAY BE DEVELOPING OVER NORTHERN COSTA RICA OR 
SOUTHERN NICARAGUA. THE AREA OF CONVECTION NEAR THE TROUGH IS 
LIKELY DUE TO INCREASING S TO SW WINDS S OF THE ITCZ AND UPPER 
LEVEL DIFFLUENT FLOW TO THE SE OF AN ANTICYCLONE NEAR 14N102W. 

OTHER BUT WEAKER TROUGHS ARE NOTED ALONG THE ITCZ ALONG 103W/104W
AND 131W. ONLY SMALL PATCHES OF SHOWERS AND TSTMS ARE NOTED IN 
ASSOCIATION WITH EACH FEATURE. 

ANOTHER TRAIN OF LONG PERIOD SWELLS 17-18 SECONDS WITH DEEP 
WATER WAVE HEIGHTS OF 9-10 FT IS CROSSING THE EQUATOR AND IS 
EXPECTED TO IMPACT THE COAST OF CENTRAL AMERICA AND MEXICO BY 
EARLY WED AND SPREAD INTO THE SRN GULF OF CALIFORNIA AND BAJA 
CALIFORNIA LATE WED AND THU.  

$$
COBB