Subject: Pacific-EN: Tropical Weather Discussion

From: SIU Weather Processor <[email-masked]>
Date: Mon, 21 Feb 2005 09:25:16 -0600

AXPZ20 KNHC 211525
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON FEB 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

..ITCZ...
ITCZ AXIS  IS ALONG THE LINE 5N77W 6N105W 6N140W. 
THERE IS SCATTERED MODERATE CONVECTION ASSOCIATED WITH THE ITCZ 
WITHIN 90 NM OF 5.3N89.2W.

DISCUSSION...
JETSTREAM IS ALONG A LINE TROUGH 12.5N140W TO BEYOND 24N107W.  
NORTH OF THE JET THERE IS A MIDDLE AND UPPER LEVEL TROUGH.  AN 
ASSOCIATED CIRCULATION CENTER IS LOCATED JUST NORTH OF THE AREA 
NEAR 33N125.5W.  AN ASSOCIATED SURFACE COLD FRONT IS ALONG THE 
LINE THROUGH 32N118.5W TO 25N122.5W TO 20N132W.  GALE FORCE 
SURFACE WINDS ARE LOCATED NORTH OF 29N WEST OF THE FRONT TO 
126W.  THESE WINDS ARE EXPECTED TO DECREASE TO LESS THAN GALE 
FORCE BY 1800 UTC TODAY.  THE UPPER LEVELS NORTH OF THE JET AXIS 
ARE DRY ALOFT INDICATING MODERATE TO STRONG UPPER LEVEL 
SUBSIDENCE.  AN EXCEPTION IS NORTH OF 25N TO THE EAST OF THE 
COLD FRONT WHERE UPWARD VERTICAL MOTION HAS ADVECTED MOISTURE TO 
THE UPPER LEVELS.  EAST OF THE FRONT AND EAST OF 120W SKIES ARE 
MOSTLY CLEAR EXCEPT FOR THE NARROW BAND OF OVERCAST MULTILAYERED 
CLOUDS ALONG THE FRONT.  WEST OF THE FRONT AND WEST OF 120W 
SKIES ARE BROKEN LOW CLOUDS.

NORTH OF THE ITCZ WITHIN 600 NM SE OF THE JET UPPER LEVEL 
MOISTURE WITH BROKEN TO OVERCAST MIDDLE AND HIGH CLOUDS IS BEING 
ADVECTED NORTHEASTWARD OVER CENTRAL MEXICO.  THE UPPER FLOW 
SOUTHEAST OF THE JET WEST OF 105W IS ANTICYCLONIC WITH DRY 
CONDITIONS ALOFT INDICATING MODERATE SUBSIDENCE IN THE UPPER 
LEVELS.

EAST OF 105W THE FLOW IS CYCLONIC IN THE UPPER LEVELS.  THERE IS 
PRONOUNCED DRY CONDITIONS ALOFT IN THIS AREA IMPLYING STRONG 
UPPER LEVEL SUBSIDENCE.  THE EXCEPTION IS THE AREA OF CONVECTION 
ASSOCIATED WITH THE ITCZ.  UPPER LEVEL MOISTURE EMANATING FROM 
THIS CONVECTION IS ADVECTING NORTHEAST TO OVER WESTERN PANAMA 
COSTA RICA AND NICARAGUA HOWEVER NO CLOUDINESS IS PRESENT AT 
THIS TIME.  SKIES ARE MOSTLY CLEAR NORTH OF THE ITCZ AND 
SCATTERED TO BROKEN SOUTH OF THE ITCZ DUE TO LOW CLOUDS.

$$
LL

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