000
AXPZ20 KNHC 180323
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC TUE MAR 18 2008

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 
0315 UTC.

...ITCZ...
ITCZ AXIS AXIS 3N78W 6N87W 3N103W 4N120W 2N140W. SCATTERED 
MODERATE WITHIN 60-90 NM OF THE AXIS BETWEEN 87W AND 93W. WIDELY 
SCATTERED MODERATE WITHIN 120-180 NM N OF THE AXIS BETWEEN 118W 
AND 124W.

...DISCUSSION...
DEEP MID TO UPPER LEVEL TROUGH EXTENDS FROM A WELL DEFINED BUT 
SLOW MOVING CYCLONIC CIRCULATION CENTER OVER EXTREME SE ARIZONA 
SWD ACROSS NW MEXICO NEAR 25N109W THEN EXTENDING SWD THROUGH 
19N115W TO 17N125W. AN AREA OF VERY STRONG SUBSIDENCE WAS 
WRAPPING AROUND THE BASE OF THE TROUGH AND COVERED THE AREA FROM 
18N TO 27N BETWEEN 105W AND 130W. FURTHER W...AN UPPER LEVEL 
ANTICYCLONE WAS NEAR 27N128W AND APPEARED TO BE IN PHASE WITH 
ANOTHER BUT DIFFUSE UPPER ANTICYCLONE NEAR 8N135W WITH AN UPPER 
RIDGE CONNECTING THE TWO FEATURES. UPPER LEVEL DIFFLUENT FLOW W 
OF THE RIDGE AXIS AND E OF A NEGATIVELY TILTED TROUGH W OF THE 
AREA ALONG 145W WAS NOTED IN THE AREA FROM 5N TO 20N W OF 130W 
WITH THE MOSTLY HIGH LEVEL MOISTURE SPREADING N TO NEAR 
20N135W...THEN TURNING E AND CONCENTRATING INTO A 180 NM WIDE 
PLUME EITHER SIDE OF POINTS 14N130W TO 15N115W...THEN TURNING 
SHARPLY NWD ACROSS CENTRAL OLD MEXICO INTO THE SRN PLAINS OF 
THE U.S. FEEDING COPIOUS AMOUNTS OF TROPICAL MOISTURE INTO A 
COMPLEX STORM SYSTEM OVER THE CENTRAL U.S. 

AN UPPER ANTICYCLONE OVER THE SRN CARIBBEAN EXTENDS WWD ACROSS 
THE GULF OF HONDURAS AND ACROSS THE TROPICAL E PAC TO A CREST 
NEAR 13N100W. ITCZ CONVECTION IS ENHANCED ALONG THE SOUTHERN 
PERIPHERY OF THIS RIDGE...BETWEEN 86W AND 90W...BUT THE 
RESULTANT DEBRIS MOISTURE IS EVAPORATING WITHIN AN AREA OF 
STRONG SUBSIDENCE. UPPER DIFFLUENCE IS ENHANCING CONVECTION 
ALONG THE ITCZ BETWEEN 118W AND 124W...WITH MOST OF THE DEBRIS 
MOISTURE ADVECTED NE INTO THE PLUME DESCRIBED ABOVE. 
 
AT THE SURFACE...STATIONARY HIGH PRES IS NEAR 34N137W 1033 
MB...WITH A RIDGE SE TO 13N100W. NW 20 KT WINDS ARE OBSERVED NE 
OF THE RIDGE EXTENDING S TO THE SOUTHERN TIP OF THE BAJA 
PENINSULA WITH SEAS 9 TO 13 FT. EASTERLY TRADES IN THE 20 TO 25 
KT RANGE ARE FOUND S OF THE RIDGE TO HAWAII WITH SEAS 9 TO 14 
FT.   

GULF OF CALIFORNIA...NW WINDS OF 20 KT ARE EXPECTED TO CONTINUE 
OVER THE SOUTHERN PORTION FOR ANOTHER 24 HOURS BEFORE 
DIMINISHING TO LESS THAN 20 KT.

GAP WINDS...EASTERLY WINDS IN THE GULF OF PAPAGAYO ARE CURRENTLY 
IN THE 20 KT RANGE AND EXPECTED TO INCREASE TO 20 TO 25 KT LATE 
TONIGHT...AND CONTINUE THROUGH 48 HOURS. N WINDS OF 15 TO 20 KT 
ARE OCCURRING IN THE GULF OF PANAMA BUT ARE EXPECTED TO DIMINISH 
TO LESS THAN 20 KT BY LATE TUE.
 
$$
COBB