000
AXPZ20 KNHC 242208
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON MAY 24 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 
2145 UTC.

...TROPICAL WAVES...
TROPICAL WAVE FROM 05N-11N ALONG 125W/126W MOVING W AT 12 KT AS 
AVERAGED OVER THE PAST 24 HOURS. THE WAVE IS ACCOMPANIED BY A 
SMALL AREA OF WEAKENING CONVECTION WITHIN 120 NM E OF THE WAVE 
AXIS. NO DEVELOPMENT IS EXPECTED AS THE WAVE IS APPROACHING AN 
AREA CHARACTERIZED BY MODERATE TO STRONG SHEAR.  

...ITCZ...
AXIS IS ALONG 06N77W TO 10N88W TO 10N104W TO 08N115W TO 06N140W. 
.SCATTERED MODERATE TO STRONG FROM 07N TO 11N BETWEEN 85W AND 
92W. SCATTERED MODERATE WITHIN 180 NM EITHER SIDE OF AXIS 
BETWEEN 92W AND 105W...AND WITHIN 120 NM EITHER SIDE OF AXIS 
BETWEEN 110W AND 123W. 

...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 135.   

AN UPPER LEVEL RIDGE EXTENDS FROM AN ANTICYCLONIC CIRCULATION 
NEAR 12N120W THROUGH ANOTHER CIRCULATION CENTER NEAR 14N102W 
THE NORTHWARD ACROSS ERN MEXICO TO TEXAS. UPPER LEVEL DIFFLUENT 
FLOW S OF THE ANTICYCLONIC CIRCULATION IS ENHANCING CONVECTION 
ALONG THE ITCZ FROM 103W-111W. UPPER LEVEL DIFFLUENT FLOW TO THE 
SE OF THE ANTICYCLONE IS ENHANCING CONVECTIVE ACTIVITY ALONG THE 
COAST OF CENTRAL AMERICA FROM GUATEMALA TO PANAMA 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 COAST AS THE RIDGE WEAKENS.

THREE TROUGHS ARE ANALYZED ALONG THE ITCZ. THE MOST SIGNIFICANT 
TROUGH EXTENDS FROM 06N85W THROUGH COSTA RICA INTO THE EXTREME 
SW CARIBBEAN AND IS ASSOCIATED WITH AN AREA OF INCREASINGLY 
DISTURBED WEATHER. LAST VISIBLE SATELLITE IMAGERY 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 110W/111W
AND 130W. SCATTERED SHOWERS AND ISOLATED TSTMS ARE WITHIN 90-120 
NM OF THE TROUGH AXIS ALONG 110W/111W. NO SIGNIFICANT CONVECTION 
IS ASSOCIATED WITH THE TROUGH ALONG 130W. 

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