000
AXPZ20 KNHC 131524
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED FEB 13 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 
1500 UTC.
 
...ITCZ...

ITCZ AXIS IS CENTERED ALONG 6N77W 4N88W 6N104W 4N110W 7N122W 
7N140W. NUMEROUS MODERATE/ISOLATED STRONG CONVECTION S OF 7N 
BETWEEN 79W-84W. SCATTERED MODERATE WITHIN 150 NM OF AXIS 
BETWEEN 87W-100W. SCATTERED MODERATE WITHIN 60 NM OF AXIS 
BETWEEN 128W-138W.

...DISCUSSION...

THE HEMISPHERIC PATTERN LONGWAVE PATTERN REMAINS QUITE 
STAGNANT...FEATURING A PERSISTENT DEEP-LAYERED TROUGH OVER 
ERN/CENTRAL NORTH AMERICA AND A RIDGE ALONG AND JUST OFF THE W 
COAST OF THE UNITED STATES. THESE FEATURES EXTEND INTO THE 
TROPICS EXCEPT THAT BROAD MID/UPPER LEVEL TROUGHING IS TRAPPED S 
OF THE RIDGE...EXTENDING S AND E OF THE HAWAIIAN ISLANDS. 
MID-LEVEL RIDGING IS EXPECTED TO STRENGTHEN OVER CENTRAL AMERICA 
AND THE ADJACENT PACIFIC WATERS OVER THE NEXT FEW DAYS.

W OF 110W...
A CLOSED MID/UPPER LEVEL LOW IS CENTERED ABOUT 725 NM SW OF SAN 
DIEGO CALIFORNIA NEAR 28N130W WITH A SHARP TROUGH AXIS REACHING 
SW PAST 24N140W. UPPER DIFFLUENCE AND A RIDGE AXIS OFF THE COAST 
OF BAJA CALIFORNIA ARE PRODUCING A BROKEN CIRRUS DECK N OF 20N 
BETWEEN 115W-130W AND LOW-LEVEL WINDS ARE DIMINISHING AS SURFACE 
HIGH PRES TO THE N WEAKENS. MODERATE/STRONG UPPER LEVEL WESTERLY 
FLOW LIES S OF 20N...DUE IN PART TO A CYCLONIC CIRCULATION 
CENTERED S OF THE EQUATOR...AND MAXIMUM WINDS WITHIN THE 
SUBTROPICAL JET ARE NEAR 80 KT ROUGHLY ALONG 8N. DOWNSTREAM...A 
SHORTWAVE TROUGH IS LOCATED ALONG 114W S OF 17N AND IS ENHANCING 
ITCZ CONVECTION TO ITS SE...PROBABLY THE MOST WIDESPREAD THAT 
HAS OCCURRED IN SEVERAL DAYS.

E OF 110W...
UPPER LEVEL FLOW OVER MEXICO AND THE FAR E PACIFIC IS SOUTHWEST 
TO WESTERLY WITH INCREASED UPPER LEVEL MOISTURE ENCROACHING ON 
THE AREA. MODERATE/STRONG SUBSIDENCE IS NOW PRIMARILY LIMITED TO 
S OF 20N WITHIN 350 NM OF THE PACIFIC COAST...ESPECIALLY STRUNG 
ACROSS THE GULF OF TEHUANTEPEC...GUATEMALA...AND HONDURAS. AN 
UPPER TROUGH EXTENDING FROM 7N102W TO THE GALAPAGOS ISLANDS IS 
PRODUCING SIGNIFICANT DIFFLUENCE TO ITS NE...A FOSTERING 
NUMEROUS MODERATE/ISOLATED STRONG CONVECTION S OF 7N BETWEEN 
79W-84W.

A COLD FRONT IS MOVING SE ACROSS THE GULF OF MEXICO AND IS 
EXPECTED TO INITIATE A SHORT-LIVED GAP EVENT OVER THE GULF OF 
TEHUANTEPEC BEGINNING BY TONIGHT. MODEL GUIDANCE SUGGESTS THAT 
THERE COULD BE A BRIEF PERIOD OF MINIMAL GALES AT THE BEGINNING 
OF THE EVENT...BUT IT PROBABLY WILL NOT BE LONG ENOUGH TO 
WARRANT THE ISSUANCE OF A WARNING. HENCE...THE FORECAST CALLS 
FOR WINDS 20-30 KT WITH HIGHER GUSTS. THE ENTIRE EVENT WILL ONLY 
LAST ABOUT 18 HOURS AND WINDS SHOULD BE LESS THAN 20 KT BY THU 
EVENING. GAP WINDS OVER THE GULF OF PAPAGAYO ARE WEAK AT THE 
MOMENT...OCCASIONALLY REACHING 20 KT...BUT THESE WINDS ARE 
EXPECTED TO STRENGTHEN AND SPREAD FARTHER W OVER THE NEXT 24-48 
HOURS.

$$
BERG