000
AXPZ20 KNHC 122203
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN JUL 12 2009

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...SPECIAL FEATURE...
CARLOS HAS WEAKENED IN THE LAST SEVERAL HOURS AND PRESENTLY IS A 
TROPICAL STORM. AT 2100 UTC...IT IS CENTERED NEAR 10.3N 121.9W  
MOVING W OR 270 DEG AT 9 KT. THE MAXIMUM SUSTAINED WINDS ARE NOW 
60 KT WITH GUSTS TO 75 KT. THE ESTIMATED MINIMUM CENTRAL 
PRESSURE IS 990 MB. THE EXTENT OF THE DEEP CONVECTION HAS 
DIMINISHED WITH A CENTRAL DENSE OVERCAST EXTENDING ONLY ABOUT 
200 NM IN DIAMETER. ELSEWHERE SCATTERED MODERATE AND ISOLATED 
STRONG CONVECTION IS NOTED IN A LARGE FEEDER BAND WITHIN 210 NM 
OVER THE NW SEMICIRCLE OF CARLOS. CARLOS IS STILL EXPECTED TO 
STRENGTHEN OVER THE NEXT FEW DAYS AS IT CONTINUES MOVING 
WESTWARD OVER WARM WATERS AND IN A LOW SHEAR ENVIRONMENT. REFER 
TO THE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 

...TROPICAL WAVES...
A TROPICAL WAVE OVER THE WESTERN CARIBBEAN EXTENDS S INTO THE 
FAR EPAC THROUGH COSTA RICA. ITS AXIS IS ALONG 84W N OF 4N. 
SCATTERED MODERATE CONVECTION IS NOTED NEAR THE SOUTHERN END OF 
THE WAVE AXIS. 

A 1009 MB LOW PRES HAS DEVELOPED ALONG A TROPICAL WAVE 
PREVIOUSLY LOCATED ALONG 105W/106W. AT 1800 UTC...THE LOW CENTER 
IS NEAR 11N104W PRODUCING A LARGE AREA OF SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION THAT COVERS FROM 06N TO 14N BETWEEN 
100W AND 110W. THE ENVIRONMENT IS FAVORABLE FOR THIS LOW TO 
DEVELOP INTO A TROPICAL CYCLONE OVER THE NEXT FEW DAYS AS IT 
MOVES WNW. 

...ITCZ...
THE ITCZ AXIS EXTENDS 08N84W TO 10N103W TO 08N110W TO 11N118W TO 
06N130W TO 06N140W. SCATTERED MODERATE ISOLATED STRONG FROM 06N 
TO 14N BETWEEN 99W AND 114W AND FROM 08N TO 10N BETWEEN 125W AND 
128W. 

...DISCUSSION...
A SHARP UPPER-LEVEL TROUGH DOMINATES THE DISCUSSION AREA W OF 
120W WITH ITS MEAN AXIS N OF 14N ALONG 128/130W. A PLUME OF 
MOISTURE IS NOTED AHEAD OF THE TROUGH AXIS N OF 25N. AN 
ASSOCIATED SURFACE TROUGH EXTENDS FROM 25N128W TO 28N126W... 
WHICH WAS THE REMNANT LOW OF TROPICAL CYCLONE BLANCA. THE 
GRADIENT NW OF THE REMNANT LOW CONTINUES TO SUPPORT NE WINDS TO 
20 KT BUT EXPECTED TO DIMINISH AS THE TROUGH WEAKENS AND DRIFTS 
W AND DISSIPATES BY TUESDAY.

A LARGE ANTICYCLONE CENTERED OVER SOUTHERN TEXAS HAS A RIDGE 
EXTENDING SW THROUGH ANOTHER ANTICYCLONE NEAR THE COAST OF BAJA 
CALIFORNIA THEN CONTINUES SW TO THE NORTH OF T.S. CARLOS. THE 
DEBRIS MOISTURE FROM CARLOS IS PULLING NWD BETWEEN THE UPPER- 
TROUGH AND THE ANTICYCLONE. 

BROAD UPPER RIDGING IS NOTED OVER THE TROPICS TO THE E OF 113W 
AND HAS BEEN ENHANCING CONVECTION OVER CENTRAL AMERICA AND ALONG 
THE ITCZ. 

GAP WINDS...N WINDS AT 20 KT HAVE SURGED THROUGH THE CHIVELA 
PASS INTO THE GULF OF TEHUANTEPEC AND EXPECTED TO CONTINUE TO 
SURGE THROUGH LATE MON THEN DIMINISH. E TRADES OF 20 KT ARE 
EXPECTED TO CONTINUE TO SURGE THROUGH THE GULF OF PAPAGAYO FOR 
THE NEXT DAYS...OCCASIONALLY REACHING 25 KT AT TIMES. NW WINDS 
15 TO 20 KT ARE EXPECTED TO CONTINUE ALONG THE W COAST OF THE 
BAJA PENINSULA FOR A COUPLE MORE DAYS.

$$
GR/COBB