000
AXPZ20 KNHC 150911
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT SEP 14 2013

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0915 UTC.

...SPECIAL FEATURE... 

TROPICAL STORM MANUEL CENTERED NEAR 17.9N 102.8W AT 0900 UTC... 
OR ABOUT 35 NM W OF LAZARO CARDENAS MEXICO...MOVING NORTH OR 335 
DEG AT 7 KT. MAXIMUM SUSTAINED WINDS REMAIN 60 KT WITH GUSTS TO 
75 KT. ESTIMATED MINIMUM PRESSURE IS 985 MB. TROPICAL STORM 
FORCE WINDS ARE OCCURRING WITHIN 80 NM NE...90 NM SE...60 NM 
SW...AND 60 NM NW OF CENTER. STRONG CONVECTION IS NOTED WITHIN 
90 NM N SEMICIRCLE...120 NM SE QUADRANT...AND 180 NM SW QUADRANT 
OF THE CENTER OF MANUEL. WINDS TO TROPICAL STORM STRENGTH ARE 
NOTED WITHIN 90 NM E SEMICIRCLE AND 60 NM W SEMICIRCLE OF 
MANUEL. THE STORM IS FORECAST TO CONTINUE TO MOVE N AND MAKE 
LANDFALL LATER THIS MORNING AND INLAND THROUGHOUT THE DAY. 
WIDESPREAD RAINFALL WILL DOMINATE SOUTHERN MEXICO...INCLUDING 
INTERIOR PORTIONS... FOR THE NEXT FEW DAYS AS THIS BROAD 
CYCLONIC CIRCULATION DRIFTS N-NW. PLEASE SEE WMO HEADER/AWIPS 
HEADERS WTPZ23 KNHC/MIATCMEP3 FOR ADDITIONAL DETAILS.  

MANUEL REMAINS EMBEDDED WITHIN A CYCLONIC GYRE ALIGNED NE TO SW 
THAT EXTENDS ACROSS S CENTRAL MEXICO INTO THE SW GULF OF 
MEXICO...WHERE HURRICANE INGRID REMAINS EMBEDDED WITHIN THE NE 
END OF THE GYRE. THIS ALIGNMENT CONTINUES TO PRODUCE A VERY LONG 
FETCH OF STRONG AND MOIST SOUTHWESTERLY WINDS EXTENDING FROM THE 
DEEP TROPICS NORTHEASTWARD INTO MEXICO BETWEEN PUERTO ANGEL AND 
ZIHUATENEJO. THIS SOUTHWESTERLY FLOW OF MOIST TROPICAL AIR WILL 
CONTINUE TO SLAM AGAINST THE SOUTHERN SLOPES OF THE SIERRA 
MADRE DEL SUR DURING THE NEXT FEW DAYS TO PRODUCE TREMENDOUS 
RAINFALL ACCUMULATIONS...BOTH NEAR AND WELL REMOVED FROM THE 
PATH OF MANUEL...WHICH WILL LEAD TO LIFE THREATENING FLASH 
FLOODING AND MUDSLIDES. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH AXIS EXTENDS FROM PANAMA NEAR 08N78W TO 
07N91W. THE TROUGH RESUMES TO THE SW OF T.S. MANUEL NEAR 16N105W 
TO 08N140W. SCATTERED MODERATE TO ISOLATED STRONG CONVECTION 
NOTED WITHIN 120 NM S AND 90 NM N OF AXIS E OF 85W.

...DISCUSSION...

AN UPPER TROUGH EXTENDING N TO S OVER N CENTRAL MEXICO ALONG 
105W CONTINUES TO PROVIDE DECENT OUTFLOW TO BOTH MANUEL AND 
HURRICANE INGRID IN THE SW GULF OF MEXICO. DRY AND SUBSIDENT NW 
FLOW BETWEEN THE UPPER TROUGH AND AN UPPER ANTICYCLONE CENTERED 
NEAR 22N125W IS SUPPRESSING CONVECTION W OF 105W...LEAVING THE 
MAIN AREA FOR THUNDERSTORMS RELEGATED TO THE ENVIRONMENT AROUND 
MANUEL. AN ASCAT PASS FROM AROUND 0430 UTC INDICATED A BROAD 
AREA OF 25 TO 30 KT SW FLOW FROM 07N TO 14N BETWEEN 95W AND 
105W...CONVERGING INTO MANUEL AND THE MONSOON TROUGH W OF 
MANUEL. CONCURRENT ALTIMETER PASSES INDICATED SEAS APPROACHING 
15 FT IN THIS AREA AS WELL. THIS PATTERN HAS PERSISTED FOR THE 
PAST SEVERAL DAYS AS THE LARGE GYRE THAT FOSTERED MANUEL 
DEVELOPED. THE LONG FETCH AND DURATION OF THIS EVENT IS CAUSING 
ROUGH AND CONFUSED SEAS ALONG MUCH OF THE MEXICAN COAST FRONT 
THE GULF OF TEHUANTEPEC TO MANZANILLO...ALONG WITH THE POTENTIAL 
FOR DANGER RIP CURRENTS ALONG THE COAST. LOOKING AHEAD...GLOBAL 
MODELS CONTINUE TO INDICATE THE SW FLOW WILL START TO RELAX 
LATER TODAY AND CONTINUE TO DIMINISH THROUGH MID WEEK WITH SEAS 
SUBSIDING ACCORDINGLY.

ELSEWHERE...A WEAK SURFACE HIGH PRES AREA IS CENTERED NW OF THE 
AREA WITH RIDGE EXTENDING W TO THE COAST OF THE BAJA PENINSULA. 
SCATTEROMETER DATA INDICATED NW TO N WINDS 15 TO 20 KT OFF THE 
SOUTHERN COAST OF BAJA PENINSULA. IN ADDITION FRESH TO STRONG NW 
WINDS WERE NOTED OF THE COAST OF SOUTHERN CALIFORNIA...THOUGH 
THESE WINDS ARE 20 KT OR LESS S OF 30N. NO SIGNIFICANT CHANGES 
ARE EXPECTED THROUGH MID WEEK.
 

$$
CHRISTENSEN