000
AXPZ20 KNHC 170317
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SAT 17 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY
THROUGH 0300 UTC.

...SPECIAL FEATURE...
POST TROPICAL REMNANT LOW PRES OF TROPICAL DEPRESSION SIX-E NEAR 
19N114W 1009 MB MOVING W-NW AT 10 KT.  MAXIMUM WIND SPEEDS 25 
GUSTS TO 35 KT.  SCATTERED MODERATE ISOLATED STRONG CONVECTION 
WITHIN 300 NM SW QUADRANT.  ALTHOUGH SYSTEM HAS WELL DEFINED 
LARGE CYCLONIC CIRCULATION...IT IS NO LONGER TROPICAL CYCLONE 
AND ITS CHANCES TROPICAL RE-DEVELOPMENT ARE DOOMED BY ITS 
SURROUNDING ENVIRONMENT.

...ITCZ...
AXIS FROM 09N85W TO 05N100W TO 06N104W THEN FROM 15N112W TO 
08N130W TO 10N140W.  SCATTERED MODERATE CONVECTION WITHIN 120 NM 
OF AXIS FROM 112W-122W AND WITHIN 60 NM OF AXIS E OF 98W.

...DISCUSSION...
UPPER LEVEL TROUGH PREVIOUSLY IN WESTERN PORTIONS OF BASIN HAS 
RETREATED W AS BROAD ANTICYCLONE AT 31N124W FORCED IT OUT OF E 
PAC.  LARGE AREA OF UPPER LEVEL CONVERGING WIND FLOW SUBSIDE N 
OF 20N W OF ANTICYCLONE PRODUCING VERY DRY AND STABLE AIR MASS. 
S OF 20N...E-NE FLOW ADVECTS LARGE AMOUNTS OF TROPICAL MOISTURE 
INTO BASIN AND ALONG ITCZ WHERE SEVERAL SURFACE FEATURES CONVERT 
INTO DEEP CONVECTION.  

LOW PRES CENTER 1010 MB AT 11N132W.  ONLY ISOLATED MODERATE 
CONVECTION REMAINS WITHIN 240 NM SW QUADRANT.  SYSTEM WEAKENED 
UNDER EASTERLY WIND SHEAR AND IS EXPECTED TO BECOME OPEN TROUGH 
WITHIN 36 HOURS.

WEAK SURFACE TROUGH EMBEDDED IN ITCZ ALONG 92W FROM 05N-12N 
UNDER STRONG EASTERLY WIND SHEAR BUT CARRIES WELL DEFINED 
CYCLONIC CIRCULATION...HAS PLENTY OF AVAILABLE MOISTURE AND SEA 
SURFACE TEMPERATURES REMAIN WARM ENOUGH TO FEED INTO MODERATE 
DEEP CONVECTION WITHIN 210 NM W AND 75 NM E OF TROUGH AXIS.  
MODEL GUIDANCE LEAN MORE TOWARD ADVERSE FACTORS AND DO NOT 
EXPECT ANY SIGNIFICANT DEVELOPMENT TO OCCUR.

CROSS EQUATORIAL SE SWELLS EXPECTED TO ENCROACH INTO E PAC S OF 
12N FROM 80W-130W LATE TONIGHT AND INCREASE THROUGH FORECAST 
PERIOD.

$$
WALLY BARNES