000
AXPZ20 KNHC 171525
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED FEB 17 2010

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...
AXIS IS ALONG 6N77W 6N97W 4N125W 5N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WITHIN 180 NM N OF AXIS FROM 100W TO 
103W.

...DISCUSSION...
AN TO UPPER LEVEL RIDGE IS OVER THE NW PORTION OF THE DISCUSSION 
AREA WITH AXIS FROM 32N128W TO 20N135W. MID/UPPER LEVEL TROUGH 
EXTENDS FROM JUST OFF THE N COAST OF BAJA CALIFORNIA NEAR 
32N117W TO 19N120W. A BROAD FLAT UPPER LEVEL RIDGE IS E OF THE 
TROUGH. A 105-115 KT JETSTREAM ENTERS THE AREA NEAR 23N140W TO 
16N120W THEN NE TO THE SOUTHERN TIP OF BAJA CALIFORNIA AND 
ACROSS CENTRAL MEXICO WHERE WINDS INCREASE TO 135 KT. EXCEPT FOR 
HIGH LEVEL MOISTURE MOVING OVER THE TOP OF THE UPPER LEVEL RIDGE 
STRONG SUBSIDENCE WITH DRY STABLE AIR AT THE MIDDLE AND UPPER 
LEVELS OF THE ATMOSPHERE IS N OF THE JET. THE SW FLOW E OF 
THE TROUGH AXIS IS ADVECTING ABUNDANT TROPICAL MOISTURE INTO 
CENTRAL MEXICO. MODERATE TO STRONG SUBSIDENCE IS ALSO NOTED S OF 
15N E OF 90W.

THE SURFACE RIDGE HAS WEAKENED AND IS SHIFTING E AS A COLD FRONT 
APPROACHES THE NW CORNER OF THE AREA. AS A RESULT THE TRADES 
HAVE DECREASED AND COVER A SMALLER AREA...FROM 9N-15N W OF 135W.
THE NW SWELLS HAVE ALSO SUBSIDED SOME IN THE 8-10 FT RANGE W OF 
105W. A COUPLE OF SURFACE TROUGHS ARE ANALYZED ALONG THE ITCZ. 
THE FIRST IS FROM 9N98W TO 3N99W SCATTERED CONVECTION IS FROM 7N 
TO 8N WITHIN 150 NM EITHER SIDE OF THE TROUGH. THE SECOND TROUGH 
WITH AXIS ALONG 8N109W TO 3N110W. NO SIGNIFICANT WEATHER IS 
ASSOCIATED WITH THE TROUGH.

STRONG HIGH PRES GRADIENT OVER SOUTHERN MEXICO IS RESULTING IN 
GALE FORCE WINDS THROUGH THE GULF OF TEHAUNTEPEC. THESE 
CONDITIONS ARE EXPECTED DECREASE TO BELOW GALE FORCE THU 
AFTERNOON. ALSO 20-25 KT ELY WINDS CONTINUE THROUGH THE GULF OF 
PAPAGAYO...THE WINDS ARE FORECAST TO INCREASE TO 20-30 KT THU.

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

$$
DGS