000
AXPZ20 KNHC 292208
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT MAR 29 2008

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.

...ITCZ...

ITCZ AXIS IS ALONG 3N78W 7N88W 2N100W 4N110W 6N122W 5N135W 
5N140W. SCATTERED STRONG WITHIN 120 NM S OF THE AXIS BETWEEN
124W-128W...AND ALONG THE COAST OF COLOMBIA FROM 4N-6N. SCATTERED
MODERATE/ISOLATED STRONG CONVECTION EXISTS FROM 3N-8N BETWEEN
85W-88.5W...AND ALSO WITHIN 120 NM S OF THE AXIS BETWEEN 
111W-114W. SCATTERED MODERATE CONVECTION IS WITHIN 60-90 NM S 
OF THE AXIS BETWEEN 125W-130W...AND ALSO WITHIN 30 NM EITHER SIDE
OF THE AXIS BETWEEN 131W-135W.

...DISCUSSION...

A SHEARED MAINLY UPPER LEVEL TROUGH EXTENDS FROM NRN MEXICO WSW
TO 24N122W TO 24N125W. A FAST MOVING SHORTWAVE TROUGH HAS 
RECENTLY ENTERED THE REGION THROUGH 30N135W AND EXTENDS SW TO A 
MID/UPPER LEVEL CYCLONIC CIRCULATION JUST ENTERING THE AREA NEAR 
21N140W. A TROUGH EXTENDS S FROM THE CIRCULATION TO NEAR 
12N142W. MODERATE SUBSIDENCE IS NOTED FROM 22N-30N E OF 125W TO 
ACROSS BAJA CALIFORNIA AND NRN MEXICO. OVER THE ERN PORTION...A 
VERY PRONOUNCED UPPER LEVEL ANTICYCLONE IS LOCATED NEAR 
15N102.5W WITH A RIDGE WSW THROUGH 12N117W TO 10N126W TO 
7.5N138W. A PLUME OF ITCZ UPPER LEVEL MOISTURE IS STREAMING NNE 
AROUND THE WRN PERIPHERY OF THE RIDGE...AND TOWARDS CENTRAL 
MEXICO. AN ELONGATED UPPER LEVEL CYCLONIC CIRCULATION IS NEAR 
3N130W WITH A COL BETWEEN IT AND THE TROUGH JUST W OF THE 
REGION. OVER THE FAR ERN SECTION...A MID/UPPER LEVEL 
ANTICYCLONIC CIRCULATION IS OVER WRN COLOMBIA WITH A RIDGE WNW 
TO 8N90W. A COL DENOTING RELATIVELY CALM WINDS AT THE SURFACE IS 
BETWEEN THIS FEATURE AND THE MAIN ANTICYCLONE NEAR 15N102.5W. 
THE TAIL END OF AN UPPER LEVEL TROUGH EXTENDS FROM THE WRN 
CARIBBEAN SW TO 11N88.5W.
 
UPPER LEVEL CONVERGENCE AND RESULTING STRONG SUBSIDENCE 
CONTINUES TO SUPPRESS CONVECTIVE ACTIVITY ALONG THE COAST OF 
CENTRAL AMERICA AND ADJACENT WATERS. ELSEWHERE...DIFFLUENT 
EASTERLIES TO THE S OF THE RIDGE MENTIONED ABOVE CONTINUE TO AID
CONVECTIVE CLUSTERS ALONG THE ITCZ MAINLY BETWEEN 110W-120W
...AND 125W-131W. A RE-APPEARING 1009 MB SURFACE LOW IS ANALYZED
8N89W. 
    
AT THE SURFACE...A RIDGE OF HIGH PRESSURE EXTENDS INTO THE AREA
THROUGH 29N140W TO 25N130W TO 19N115W. NE TO E TRADES OF 20 KT 
PERSIST SW OF THE RIDGE WITH SEAS IN THE 8-10 FT. E OF THE RIDGE
...N OF 23N BETWEEN 123W-112W...NW-N WINDS OF 20 KT ARE OBSERVED
WITH SEAS THERE IN THE 10-13 FT RANGE IN NW SWELL. THESE WINDS
ARE EXPECTED TO DIMINISH DURING THE NEXT 24-30 HOURS AS THE 
RIDGE WEAKENS WITH AN APPROACH OF A COLD FRONT JUST TO THE NORTH 
OF THE AREA. 

GAP WINDS...A HIRES QUIKSCAT PASS FROM THIS MORNING SHOWED
20 KT WINDS IN THE GULF OF PAPAGAYO SUGGESTING DIURNAL 
FLUCTUATIONS IN THIS GAP WIND EVENT. NWP MODELS SUGGEST WINDS 
WILL FINALLY DROP BELOW 20 KT WITHIN THE NEXT 24 HRS.

$$
AGUIRRE