000
AXPZ20 KNHC 082206
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC MON JUL 08 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 ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...SPECIAL FEATURES...

THE CENTER OF TROPICAL STORM ERICK AT 08/2100 UTC IS NEAR 22.6N 
110.8W. ERICK IS MOVING NW AT 9 KNOTS. THE ESTIMATED MINIMUM 
CENTRAL PRESSURE IS 1001 MB. THE MAXIMUM SUSTAINED WIND SPEED IS 
40 KT WITH GUSTS TO 50 KNOTS. ERICK IS FORECAST TO CONTINUE TO 
WEAKEN DURING THE NEXT 48 HRS AS IT MOVES OVER COOLER SEA 
SURFACE TEMPERATURES AND INTO A DRIER AND MORE STABLE 
ENVIRONMENT. TROPICAL STORM CONDITIONS COULD OCCUR DURING THE 
NEXT FEW HOURS ALONG THE SW PORTION OF BAJA CALIFORNIA SUR. 
PLEASE READ THE LATEST FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCMEP5/WTNT25 KNHC AND THE PUBLIC ADVISORY UNDER 
MIATCPEP5/WTPZ35 KNHC FOR MORE DETAILS. SCATTERED MODERATE 
ISOLATED STRONG WITHIN 90 NM N SEMICIRCLE. SCATTERED MODERATE 
ELSEWHERE WITHIN 60 NM S SEMICIRCLE QUADRANT.  THE HAZARDS 
AFFECTING LAND ARE... LIFE-THREATENING SURF AND RIP CURRENT 
CONDITIONS...HEAVY RAINFALL THAT MAY CAUSE LIFE-THREATENING 
FLASH FLOODS AND MUD SLIDES...AND THE TROPICAL STORM FORCE WINDS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...   
     
THE MONSOON TROUGH AXIS EXTENDS FROM 09N83W TO 08N95W TO 
07N115W. THE ITCZ AXIS EXTENDS FROM 13N117W TO 06N140W. 
SCATTERED MODERATE CONVECTION IS OCCURRING WITHIN 60 NM OF THE 
ITCZ BETWEEN 125W AND 135W.  SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS OCCURRING WITHIN 120 NM OF TROUGH AXIS E OF 90W. 

...DISCUSSION... 

THE MAJORITY OF THE AREA REMAINS UNDER RATHER DRY AND STABLE 
CONDITIONS ALOFT AS AN UPPER LEVEL ANTICYCLONE LIFTING NWD NEAR 
18N130W....AND ANOTHER ANTICYCLONE NEAR 23N119W EXTEND BROAD 
RIDGING OVER THE PORTION OF THE AREA W OF ABOUT 120W. BROAD 
UPPER TROUGHING IS PRESENT ACROSS THE NW PORTION OF THE AREA 
ASSOCIATED WITH A CYCLONIC VORTEX MOVING SLOWLY EASTWARD NW OF 
THE AREA AT 34N137W.

E OF 120W...SUBSIDENT NE SHEAR ALOFT ASSOCIATED WITH AN UPPER 
ANTICYCLONE OVER CENTRAL MEXICO NEAR 24N102W IS INHIBITING 
ORGANIZED CONVECTION BETWEEN 90W AND 98W. THE EXCEPTION IS ALONG 
THE MONSOON TROUGH BETWEEN 100W AND 110W WHERE SW FLOW INTO THE 
TROUGH IS ENCOUNTERING MODERATE NE FLOW. A SHARP UPPER TROUGH 
EXTENDS FROM THE SE YUCATAN PENINSULA SW TO 10N97W ALLOWING FOR 
FAVORABLE CONDITIONS FOR CONVECTIVE DEVELOPMENT FARTHER E ALONG 
WITH THE A TROPICAL WAVE MOVING INTO THE SW CARIBBEAN IS 
STARTING TO INTERACT WITH THE MONSOON TROUGH THROUGH COSTA RICA 
AND PANAMA. THIS ALONG WITH THE SUPPORT ALOFT ON THE E SIDE OF 
THE TROUGH WILL ALLOW CONVECTIVE DEVELOPMENT TO THE E OF 90W 
OVER THE NEXT COUPLE OF DAYS.

GULF OF CALIFORNIA...S WINDS TO 20 KT OVER THE SOUTHERN 
ENTRANCES TO THE GULF OF CALIFORNIA DUE TO TROPICAL STORM ERICK 
ARE STILL OCCURRING. MODERATE TO FRESH SE FLOW IS EXPECTED ALONG 
THE GULF OF CALIFORNIA OVER THE NEXT COUPLE OF DAYS AS ERICK 
MOVES NW PAST CABO SAN LUCAS TOWARD THE OPEN WATER ON THE WEST 
SIDE OF THE BAJA PENINSULA.

SCATTEROMETER DATA AND TOGA TAO BUOY OBSERVATIONS INDICATED A 
BROAD AREA OF 15 TO 20 KT S TO SW FLOW INTO THE MONSOON TROUGH W 
OF 115W. THIS HAS BEEN AIDING DEVELOPMENT OF PULSES OF 
THUNDERSTORMS ALONG THE MONSOON TROUGH...BUT THESE HAVE BEEN 
RELATIVE SHORT LIVED AS SUBSIDENT NORTHERLY FLOW ALOFT 
ASSOCIATED WITH THE UPPER ANTICYCLONE NEAR 18N130W HAS BEEN 
INHIBITING CONVECTIVE GROWTH. GLOBAL MODELS INDICATE A SERIES OF 
WEAK LOW PRES AREAS FORMING ALONG THE MONSOON TROUGH THROUGH MID 
WEEK...PRIMARILY BETWEEN 110W AND 130W.

A SURGE OF SOUTHERLY SWELL WITH SEAS TO 9 FT WILL CROSS THE 
EQUATOR TODAY BETWEEN 92W AND 125W...AND DIMINISH BY WED. 

$$ 
AGUIRRE/LANDSEA