000
AXPZ20 KNHC 291518
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC SAT MAR 29 2008

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1515 UTC.

...ITCZ...

ITCZ AXIS IS ALONG 3N78W 7N87W 3N100W 8N115W 5N140W. SCATTERED 
MODERATE ISOLATED STRONG WITHIN 120-180 NM EITHER SIDE OF THE 
AXIS BETWEEN 110W AND 135W. WIDELY SCATTERED MODERATE FROM 3N TO 
8N BETWEEN 86W AND 90W. 

...DISCUSSION...

A SHEARED MAINLY UPPER LEVEL TROUGH EXTENDS FROM THE SRN CONUS 
THROUGH A CYCLONIC CIRCULATION OVER NRN MEXICO NEAR 28N104W 
ACROSS THE NRN PORTION OF THE AREA TO ANOTHER CYCLONIC 
CIRCULATION W OF THE AREA NEAR 22N146W. STRONG SUBSIDENCE WITHIN 
THE TROUGH AND N OF A SUBTROPICAL JET STREAK AND UPSTREAM OF A 
MUCH LARGER UPPER LEVEL TROUGH IS DOMINATING THE NORTHERN 
PORTION OF THE DISCUSSION AREA N OF 20N. A PLUME OF MOISTURE 
E OF THE FIRST CYCLONIC CIRCULATION OVER MEXICO IS SPREADING 
NORTHEASTWARD FROM THE EASTERN PACIFIC OVER NRN MEXICO AND THE 
DEEP SOUTH OF THE CONUS. UPPER LEVEL CONVERGENCE AND RESULTING 
STRONG SUBSIDENCE CONTINUES TO SUPPRESS CONVECTIVE ACTIVITY 
ALONG THE COAST OF CENTRAL AMERICA AND ADJACENT WATERS. 
ELSEWHERE...DIFFLUENT EASTERLIES ARE SUPPORTING AREAS OF 
CONVECTION ALONG THE ITCZ MAINLY BETWEEN 110W AND 135W AND IN 
THE VICINITY OF A 1009 MB SFC LOW NEAR 8N89W. 
    
AT THE SURFACE...A RIDGE OF HIGH PRESSURE EXTENDS THROUGH 
29N140W 23N120W 18N105W. NE TO E TRADES OF 20 KT PERSIST SW OF 
THE RIDGE WITH SEAS TO 10 FT. E OF THE RIDGE AXIS...NW WINDS TO 
THE W COAST OF THE BAJA PENINSULA ARE NEAR 20 KT PER THE MOST 
HIGH RESOLUTION QUIKSCAT PASS. EXPECT WINDS TO DECREASE DURING 
THE NEXT 24-36 HOURS AS THE RIDGE WEAKENS WITH AN APPROACH OF A 
COLD FRONT JUST TO THE NORTH OF THE AREA. 

GAP WINDS...AN 1144 UTC HIRES QUIKSCAT OVERPASS ONCE AGAIN 
INDICATED 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 BY SUN AFTERNOON. 

$$
COBB