Subject: Pacific-EN: Tropical Weather Discussion

From: SIU Weather Processor <[email-masked]>
Date: Tue, 22 Feb 2005 15:57:17 -0600

AXPZ20 KNHC 222157
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE FEB 22 2005

TROPICAL WEATHER DISCUSSION FOR EASTERN PACIFIC OCEAN FROM 
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 
2145 UTC.

..ITCZ...
ITCZ AXIS IS ALONG 7N77W 7N85W 3N101W 8N107W 5N129W 8N132W 
6N140W. WIDELY SCATTERED MODERATE WITHIN 30 NM OF AXIS W OF 130W.

DISCUSSION...
A 1300 NM WIDE WESTERLY JETSTREAM IS CENTERED ALONG A LINE 
TROUGH 15N140W TO 17N115W WHERE THE FLOW SPLITS WITH ONE BRANCH 
CONTINUING CYCLONICALLY NE TO BEYOND 30N99W. THE SECOND BRANCH 
TURNS ANTICYCLONICALLY SE AND LOSES IDENTITY ALONG 104W WHERE 
CLOUD TRACERS DISSIPATE IN STRONG DRY UPPER AIR. 

N OF THE JET A MID TO UPPER LEVEL NEGATIVE TILT SHORT WAVE 
TROUGH IS EMBEDDED IN A LONG WAVE RIDGE. THE ASSOCIATED DEEP 
LAYERED CYCLONE IS CENTERED JUST N OF THE DISCUSSION AREA NEAR 
34N122W AND IS NOW MOVING E WITH TIME. AT THE SURFACE THE LOW IS 
ANALYZED AT 1008 MB WITH A DISSIPATING COLD FRONT LYING ALONG 
32N116W TO 25N120W.

IN THE TROPICS...UPPER DEBRIS MOISTURE IS OBSERVED WITHIN 60 NM 
EITHER SIDE OF A LINE FROM 7N142W TON 9N129W...ORIGINATING FROM 
ITCZ CONVECTION NEAR 7N147W AND FROM THE CONVECTION THAT 
DEVELOPED ALONG THE ITCZ W OF 130W. OTHERWISE...DRY AIR IS 
INDICATED S OF THE JET.

IN THE SUBTROPICS...THE UPPER LEVELS N OF THE JET...ROUGHLY N OF 
20N...ARE DRY INDICATING MODERATE TO STRONG UPPER LEVEL 
SUBSIDENCE. WITHIN THE JET...A 600 NM WIDE BAND OF UPPER 
MOISTURE HAS AXIS ALONG 14N140W 16N120W...THEN NARROWS TO 180 NM 
WIDE TO OVER THE MEXICAN COAST AT 22N106W...THEN THE PLUME 
WIDENS AGAIN COVERING MOST OF THE GULF OF MEXICO.  

AN UPPER ANTICYCLONE IS ESTIMATED NEAR 9N98W. AN UPPER 
ANTICYCLONE IS ESTIMATED NEAR 8N61W WITH ITS ENVELOPE OF 
ANTICYCLONIC FLOW ALONG POINTS 1N88W 13N74W 15N63W. BETWEEN 
THESE TWO RIDGES...AN UPPER TROUGH IS NOTED FROM 3N86W TO TO 
11N78W AND IS SHIFTING E AND LOSING IDENTITY WITH TIME. 
RESULTANT 
STRONG DRY AIR ALOFT IS NOTED SE OF LINE 10N111W 22N82W.

NE WINDS ARE SPREADING W ACROSS CENTRAL AMERICA INTO THE PAC 
WITHIN 60 NM OF LINE 12N87W 8N93W. NLY WINDS OCCASIONALLY 
INCREASE TO 20 KT IN THE GULF OF TEHUANTEPEC...BUT USUALLY 
DECREASE BEFORE SEAS CAN BUILD. SIMILAR CONDITIONS ARE LIKELY 
OCCURRING IN THE GULF OF PANAMA.   

$$
NELSON

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
To unsubscribe from WX-TROPL send e-mail to [email-masked] with
"unsub wx-tropl" in the body of your message. For help with WX-TROPL
write to [email-masked] or see http://wxlist.5280tech.com. For more
information on tropical weather products, see the NHC Homepage
at http://www.nhc.noaa.gov.