000
AXPZ20 KNHC 130951
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC MON JUL 13 2009

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0945 UTC.

...SPECIAL FEATURE...
TROPICAL STORM CARLOS IS CENTERED NEAR 10.2N 124.1 AT 13/0900 
UTC IS MOVING W OR 270 DEG AT 11 KT. THE MAXIMUM SUSTAINED WINDS 
ARE 45 KT WITH GUSTS TO 55 KT. THE ESTIMATED MINIMUM CENTRAL 
PRESSURE IS 1000 MB. CARLOS HAS WEAKENED CONSIDERABLY OVER THE 
PAST 24 HOURS. NUMEROUS STRONG CONVECTION IS OBSERVED IN A 
CLUSTER WITHIN 60 NM OF CENTER WITH SCATTERED MODERATE AND 
ISOLATED STRONG CONVECTION NOTED ELSEWHERE WITHIN 120 NM EITHER 
SIDE OF LINE FROM 08N122W TO 12N125W...WITH WEAK BANDING N OF 
THE CENTER. CARLOS IS STILL UNDER AN UPPER RIDGE AND PASSING 
OVER WARM SEAS SURFACE WATERS AND IS FORECAST TO GAIN A LITTLE 
STRENGTH OVER THE NEXT FEW DAYS BECOMING A STRONG TROPICAL STORM 
AGAIN. REFER TO THE LATEST NHC FORECAST ADVISORY UNDER AWIPS/WMO 
HEADERS MIATCMEP4/WTPZ24 KNHC FOR MORE DETAILS. 

...TROPICAL LOW... 
A TROPICAL WAVE SPAWNED A SURFACE LOW PRES 1009 MB NEAR 11N106W 
YESTERDAY. CONVECTION IS CURRENTLY INCREASING WITHIN 210 NM OF 
CENTER OVER THE NE SEMICIRCLE WHERE SCATTERED MODERATE TO STRONG 
TSTMS ARE FLARING. THE PRES GRADIENT IS TIGHT WITHIN 300 NM N 
SEMICIRCLE WHERE NE TO E WINDS ARE ALREADY AT 20 KT WITH 
ASSOCIATED SEAS TO 8 FT. THE LOW IS IN THE MONSOON FLOW WITH SW 
WINDS AT 15 TO 20 KT WITHIN 240 NM OVER THE S SEMICIRCLE. 
TROPICAL CYCLONE FORMATION IS POSSIBLE AS THIS LOW PRES MOVES W 
NW OVER THE NEXT FEW DAYS.

...ITCZ...
THE ITCZ AXIS EXTENDS FROM 08N77W TO 07N92W TO 11N106W TO 
08N110W TO 11N110W TO 07N140W. SCATTERED MODERATE ISOLATED 
STRONG CONVECTION IS NOTED FROM 06N TO 14N BETWEEN 95W AND 118W
SURROUNDING THE TROPICAL LOW PRES DESCRIBED ABOVE...AND ALSO 
FROM 06N TO 11N BETWEEN 125W AND 137W. 

...DISCUSSION...
AN UPPER LEVEL TROUGH DOMINATES THE DISCUSSION AREA N OF 10N W 
OF 124W AND IS ACCOMPANIED BY DRY UPPER AIR. A LARGE ANTICYCLONE 
IS CENTERED OVER THE TEXAS AT 31N102W AND ANOTHER ANTICYCLONE IS 
MOW NOTED NEAR 28N108W. AN UPPER RIDGE EXTENDS SW TO A SHARP 
CREST AT 13N127W...WHICH IS JUST TO THE N OF TROPICAL STORM 
CARLOS. AN UPPER CYCLONE IS NOTED OVER W CENTRAL OLD MEXICO AT 
20N130W AND IS MOVING W WITH TIME AND ERODING THE SOUTHERN 
PORTION OF THE LARGE RIDGE TO THE N. BUT BROAD UPPER RIDGING IS 
NOTED SE OF THIS CYCLONE OVER THE DEEP TROPICS...S OF 15N E OF 
110W...AND HAS BEEN ENHANCING CONVECTION WITHIN 60 NM OF MEXICAN 
COAST FROM 97W TO 106W...AND ALONG THE ITCZ BETWEEN 95W AN 118W 
INCLUDING THE NEWLY FORMING TROPICAL LOW PRES PREVIOUSLY 
MENTIONED. THE RESULTANT DEBRIS MOISTURE COVERS THE UPPER LEVELS 
OF THE PACIFIC S OF 17N BETWEEN 93W AND 120W MIXING WITH THE 
DEBRIS MOISTURE FROM TROPICAL CYCLONE CARLOS.

GAP WINDS...N WINDS AT 20 TO 25 KT CONTINUE TO SURGE THROUGH THE 
CHIVELA PASS INTO THE GULF OF TEHUANTEPEC AND ARE EXPECTED TO 
DIMINISH TO LESS THAN 20 KT LATE TONIGHT. EASTERLY TRADES AT 15 
TO 25 KT...SEAS TO 9 FT...ARE EXPECTED TO CONTINUE TO SURGE 
THROUGH THE GULF OF PAPAGAYO FOR THE NEXT DAYS. 

SE SWELLS TO 8 FT ARE CROSSING THE EQUATOR OVER THE WATERS S OF 
03N BETWEEN 100W AND 127W. SW SWELLS WILL ALSO PUSH N TO THE 
EQUATOR TONIGHT AND WILL MIX WITH SE SWELL TRAIN OVER ALL THE 
WATERS S OF 08N TO THE W OF 90W BY WED.

$$
NELSON