000
AXPZ20 KNHC 151530
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI JAN 15 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1500 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
AXIS IS ALONG 5N78W 7N90W 4N105W 6N115W 4N130W 6N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WITHIN 90 NM N OF AXIS FROM 
95W TO 109W. SCATTERED MODERATE CONVECTION WITHIN 60 NM EITHER 
SIDE OF AXIS BETWEEN 112W AND 115W.

...DISCUSSION...
MID/UPPER LEVEL TROUGH OVER THE NW PORTION OF THE DISCUSSION 
AREA EXTENDS FROM 32N137W TO 25N140W. ASSOCIATED COLD FRONT
ENTERS THE AREA AT 32N135W TO 25N140W. OVERCAST MULTILAYERED
CLOUDS WITH SCATTERED SHOWERS ARE WITHIN 150 NM E OF THE FRONT.
A 80-95 KT SLY JETSTREAM EXTENDS FROM 26N140W TO 32N136W.
MODERATE TO STRONG SUBSIDENCE IS W OF THE TROUGH AXIS. BROAD 
UPPER LEVEL ANTICYCLONIC CIRCULATION IS CENTERED NEAR 12N132W. 
RIDGE AXIS EXTENDS FROM THE CIRCULATION TO 32N122W.  MODERATE TO 
STRONG SUBSIDENCE WITH VERY DRY AND STABLE AIR MASS IS WITHIN 
360 NM EITHER SIDE OF RIDGE AXIS S OF 23N. DOWNSTREAM MID/UPPER 
LEVEL TROUGH AXIS EXTENDS FROM A CYCLONIC CIRCULATION OVER 
NORTHERN MEXICO NEAR THE BIG BEND OF TEXAS ACROSS CENTRAL MEXICO 
TO 13N105W. A 120-140 KT NLY JET FROM SE ARIZONA ACROSS MEXICO
NEAR 23N104W...THEN CURVES TO THE E. 

A 1024 MB HIGH PRES IS CENTERED AT 31N123W WITH RIDGE COVERING 
THE AREA N OF 11N W OF 110W. TIGHT PRES GRADIENT INDUCED BY 
RIDGE PRODUCING STRONG NE TO E TRADES ALONG SOUTHERN PERIPHERY.  

SEVERAL WEAK SURFACE TROUGHS ARE EMBEDDED IN ITCZ. ONE S OF 9N 
ALONG 97W A SECOND S OF 9N ALONG 106W ANOTHER S OF 8N ALONG 118W 
ANOTHER S OF 8N ALONG 127W AND FINALLY ANOTHER S OF 8N ALONG 
135W.

ELY WINDS 20 KT CONTINUE IN THE GULF OF PAPAGAYO AND ARE 
EXPECTED TO BE BELOW 20 KT SAT NIGHT.

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
DGS