000
AXPZ20 KNHC 160321
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED APR 16 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 
0300 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 04N77W TO 01N88W TO 07N108W TO 
04N140W. SCATTERED MODERATE CONVECTION FROM 07N-12N BETWEEN 
97W-120W. SCATTERED MODERATE/ISOLATED STRONG FROM 03N-08N W OF 
126W.

...DISCUSSION...

W OF 115W...
A CUT-OFF UPPER LOW IS LOCATED JUST W OF THE AREA NEAR 25N141W 
WITH A TROUGH AXIS EXTENDING SWD ALONG 141W TO NEAR 5N...AND 
BROAD SOUTHWESTERLY FLOW LYING TO THE E TO NEAR 115W. THE UPPER 
LOW IS ATTACHED TO ANOTHER TROUGH AXIS WHICH EXTENDS TO SOUTHERN 
CALIFORNIA...BUT THE BULK OF THE TROUGHING LIES WELL TO THE N 
ACROSS THE WESTERN UNITED STATES. FARTHER S...A SHORTWAVE TROUGH 
IS EMBEDDED WITHIN THE LARGER-SCALE TROUGH FROM 12N124W TO 
2N115W AND UPPER DIFFLUENCE IS ENHANCING CONVECTION ALONG THE 
ITCZ W OF 128W. IN THE LOW-LEVELS...THE SUBTROPICAL RIDGE IS IN 
PLACE FROM 30N134W TO 21N115W WITH MODERATE 20-25 KT TRADES 
LYING SW OF THE AXIS...AND LARGE 8-13 FT SWELLS MOVING INTO THE 
NW PART OF THE REGION. A BROKEN STRATOCUMULUS FIELD LIES N OF 
14N W OF 122W WHILE SKIES ARE CLEARING NEAR THE BAJA CALIFORNIA 
COAST.

E OF 115W...
LARGE-SCALE RIDGING IS IN PLACE OFF THE SW COAST OF MEXICO WITH 
A MEAN AXIS STRETCHING FROM NW COLOMBIA TO NEAR 13N115W. A 
SHORTWAVE TROUGH...AS MENTIONED ABOVE...LIES WITHIN THE TROPICS 
JUST W OF 115W BUT IS PRODUCING DOWNSTREAM UPPER DIFFLUENCE... 
RESULTING IN WIDESPREAD CONVECTIVE ACTIVITY FROM 7N-14N BETWEEN 
96W-115W. DRIER WEATHER IS LOCATED E OF 95W DUE TO AN UPPER HIGH 
CENTERED OVER NICARAGUA AND COSTA RICA...AND AN ASSOCIATED PATCH 
OF MODERATE/STRONG SUBSIDENCE OVER SRN CENTRAL AMERICA. FARTHER 
N...A PROGRESSIVE UPPER LEVEL SHORTWAVE RIDGE IS LOCATED ALONG 
105W MOVING ACROSS NW MEXICO...TRANSITIONING INTO A DEEP-LAYERED 
TROUGH OVER THE GULF OF MEXICO. MODERATE/STRONG SUBSIDENCE IS 
ASSOCIATED WITH THE RIDGE AXIS AND IS SPREADING ACROSS NORTHERN 
MEXICO.

GALE CONDITIONS ARE OCCURRING OVER THE GULF OF TEHUANTEPEC DUE 
TO HIGH PRES CENTERED OVER THE LOWER MISSISSIPPI VALLEY...WITH 
WINDS CURRENTLY AS HIGH AS 35 KT. THE HIGH IS EXPECTED TO SHIFT 
SLOWLY E OVER THE NEXT DAY AND WINDS WILL DROP BELOW GALE FORCE 
BY WED MORNING...THEN BELOW 20 KT BY THU AFTERNOON. WINDS ARE 
CURRENTLY 20 KT OVER THE GULF OF PAPAGAYO AND SHOULD REMAIN 
STEADY OVER THE NEXT 48 HRS...OCCASIONALLY REACHING 20-25 KT.

$$
BERG