000
AXPZ20 KNHC 152137
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC MON AUG 15 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE 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 
2100 UTC.

...SPECIAL FEATURES...
TROPICAL DEPRESSION SIX E NEAR 12.0N 132.3W 1007 MB AT 2100 UTC 
AUG 15 MOVING W OR 270 DEG AT 9 KT. MAXIMUM SUSTAINED WINDS 30 
KT GUSTS 40 KT. HIGHEST SEAS 11 FT. SIX E IS EXPECTED TO MOVE 
WEST AND INTENSIFY INTO A TROPICAL STORM DURING THE NEXT 24 HOURS
AS IT MOVES INTO A MORE FAVORABLE ENVIRONMENT. REFER TO FORECAST/
ADVISORIES ISSUED UNDER WMO HEADER WTPZ21 KNHC AND AWIPS HEADER 
MIATCMEP1 FOR FURTHER DETAILS.

1008 MB LOW PRES LOCATED NEAR 11.5N94W HAS WIDELY SCATTERED 
MODERATE CONVECTION WITHIN 180 NM OF ITS CENTER. THE LOW IS 
FORECAST TO MOVE NW S OF MEXICO OVER THE NEXT TWO DAYS...AND MAY 
DEVELOP INTO A TROPICAL CYCLONE.

...ITCZ/MONSOON TROUGH...
MONSOON TROUGH FROM 09N82W TO LOW PRES 11.5N94W TO 14N102W TO 
LOW PRES 11.5N109W TO 13N123W TO TROPICAL DEPRESSION SIX E TO 
10N140W. SCATTERED MODERATE ISOLATED STRONG CONVECTION N OF 03N 
BETWEEN 80W AND 88W...N OF 07N BETWEEN 92W AND 102W...AND WITHIN 
150 NM OF A LINE FROM 16N107W TO 10N113W...AND FROM 06N110W TO 
10N126W.

...DISCUSSION...
A WEAK COLD FRONT EXTENDING SSW TO NEAR 30N139W HAS DISRUPTED THE
PRESSURE GRADIENT ACROSS THE NW PORTION OF THE DISCUSSION AREA. 
AS A RESULT...WINDS ARE AROUND 10 KT WITH SEAS 4-5 FT N OF 20N 
AND W OF 125W. THE FRONT WILL CONTINUE TO MOVE EAST N OF 30N 
TONIGHT AND IS EXPECTED TO DISSIPATE TUE WHILE WEAK HIGH PRES 
BUILDS WNW OF THE AREA NEAR 32N152W. THIS WILL BRING A SLIGHT 
INCREASE IN TRADE WINDS AND ALLOW SEAS TO BUILD TO 6 FT BY WED. 
LOW PRES THERMAL TROUGH IN NW MEXICO AND BAJA CALIFORNIA WILL 
MAINTAIN MODERATE NW WINDS IN THE NE PORTION OF THE DISCUSSION 
AREA N OF 22N E OF 118W.

THE DEEP TROPICS ARE CHARACTERIZED BY AN ACTIVE MONSOON TROUGH 
WITH A STRING OF LOW PRESSURE CENTERS ALL ALONG THE TROUGH AXIS 
NEAR 11.5N94W...11.5N109W AND NEWLY-FORMED TROPICAL DEPRESSION 
SIX E NEAR 12.0N 132.3W. DEEP CONVECTION ASSOCIATED WITH THE LOW 
NEAR 11.5N 109W HAS INCREASED OVER THE PAST 6-8 HOURS. MODEL 
GUIDANCE SHOWS VERY LITTLE DEVELOPMENT FROM THIS LOW OVER THE 
NEXT 24-48 HOURS...BUT DO MAINTAIN A WELL ORGANIZED CIRCULATION 
WITH 15-20 WINDS...MOVING WEST THROUGH THU. ANIMATED SATELLITE 
IMAGERY SHOWS MODERATE TO STRONG LOW LEVEL INFLOW S OF THE LOW 
NEAR 11.5N94W AND WEAK ANTICYCLONIC FLOW ALOFT. GLOBAL MODEL 
GUIDANCE INCLUDING THE GFS ECMWF AND UKMET MODELS ARE MORE 
BULLISH ON THIS SYSTEM...AS ALL INDICATE FURTHER DEVELOPMENT 
THROUGH THE END OF THE WEEK AS IT MOVES NW S OF MEXICO. 

EXPECT THE MONSOON TROUGH TO REMAIN RELATIVELY ACTIVE E OF 120W 
ALONG 10-15N THE NEXT SEVERAL DAYS WITH SEAS BUILDING TO 10 FT S 
OF THE TROUGH AXIS FROM SW WINDS AROUND 20 KT ACROSS THE REGION.

$$
MUNDELL