000
AXPZ20 KNHC 092137
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC FRI FEB 09 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2115 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 1N79W 6N84W 3N105W 5N114W 5N140W. 
ISOLATED SHOWERS/TSTMS WITHIN 30 NM OF THE AXIS BETWEEN 
95W-103W. ISOLATED SHOWERS/TSTMS WITHIN 60 NM OF THE AXIS W OF 
130W.

...DISCUSSION...

THE COMPLEX CYCLONIC GYRE WHICH WAS LOCATED BETWEEN HAWAII AND 
ALASKA YESTERDAY HAS SHIFTED SLIGHTLY E TO A POSITION ALONG 
142W/143W TODAY...AND STILL HARBORS SEVERAL EMBEDDED CIRCULATION 
WHICH ARE ROTATING AROUND A COMMON CENTER. A SHORTWAVE TROUGH IS 
CURRENTLY ROTATING THROUGH THE BASE OF THE GYRE ALONG 142W TO 
ABOUT 26N AND SHOULD SOON BE FOLLOWED WITHIN THE NEXT 24 HRS BY 
A SECOND SHORTWAVE WHICH IS NOW NEAR 38N147W. THE FIRST 
SHORTWAVE IS ACCOMPANIED BY A SURGE OF WINDS TO GALE FORCE WHICH 
WILL BRUSH THE FAR NW CORNER OF THE AREA WITHIN THE NEXT SEVERAL 
HOURS...BUT SHOULD GENERALLY STAY JUST TO THE N. A SLOW-MOVING 
COLD FRONT LIES FARTHER SE FROM 30N128W TO 24N140W AND THERE HAS 
BEEN ENOUGH LOW-LEVEL MOISTURE AND CONVERGENCE FOR SCATTERED 
SHOWERS TO FORM WITHIN 150 NM NW OF THE BOUNDARY. AS THE MAIN 
STORM SYSTEM LIFTS NE...ACTIVITY ALONG THE FRONT IS EXPECTED TO 
SLOWLY DIE OFF WITHIN THE NEXT 48 HRS.

JUST DOWNSTREAM...AN UPPER RIDGE AXIS LIES FROM 17N124W NE TO 
FAR NW MEXICO...THEN THE FLOW TRANSITIONS INTO A TROUGH ALONG 
108W. THE TROUGH IS PARTLY CUT-OFF FROM THE SWIFTER MID-LATITUDE 
FLOW OVER THE U.S. AND THUS IS ONLY MOVING SLOWLY EWD ACROSS 
MEXICO. IN ITS WAKE...STRONG UPPER CONFLUENCE IS PRODUCING 
STRONG SUBSIDENCE ACROSS A GOOD PORTION OF THE AREA S OF 20N TO 
THE ITCZ...W OF THE TROUGH AXIS.

THE INFLUENCE OF THE TROUGH ALONG 108W IS PRODUCING BROAD SWLY 
FLOW ACROSS SRN MEXICO/GUATEMALA AND THE ADJACENT PACIFIC 
WATERS...BUT A LACK OF DEEP MOISTURE IS INHIBITING ACTIVE 
WEATHER. THE MID-LEVEL RIDGE AXIS EXTENDS FROM THE CARIBBEAN WWD 
ALONG 15N WITH STRONG/MODERATE SUBSIDENCE CONTINUING ACROSS 
CENTRAL AMERICA. SKIES ARE GENERALLY CLEAR UP AND DOWN THE COAST 
AND THE LARGE EXPANSE OF ADJACENT WATERS...AND THE GAP WINDS ARE 
NOT SIGNIFICANT AT THIS TIME.

$$
BERG