000
AXPZ20 KNHC 080917
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0900 UTC.

...SPECIAL FEATURES...

THE CENTER OF TROPICAL STORM ERICK AT 08/0900 UTC IS NEAR 21.3N 
109.5W. ERICK IS MOVING NORTHWESTWARD 8 KNOTS. THE ESTIMATED 
MINIMUM CENTRAL PRESSURE IS 998 MB. THE MAXIMUM SUSTAINED WIND 
SPEEDS ARE 45 KNOTS WITH GUSTS TO 55 KNOTS. ERICK IS FORECAST TO 
CONTINUE TO WEAKEN DURING THE NEXT 48 HRS AS IT MOVES OVER 
WATERS WITH COMPARATIVELY COOLER SEA SURFACE TEMPERATURES AND 
VERTICAL SHEAR. PLEASE READ THE LATEST FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP5/WTNT25 KNHC AND THE PUBLIC ADVISORY 
UNDER MIATCPEP5/WTPZ35 KNHC FOR MORE DETAILS. TROPICAL STORM 
CONDITIONS ARE EXPECTED DURING THE TIME WHILE THE CENTER OF 
ERICK MAKES IT CLOSEST POINT OF APPROACH TO CABO SAN LUCAS THIS 
AFTERNOON. CONVECTIVE PRECIPITATION...SCATTERED TO NUMEROUS 
STRONG WITHIN 60 NM OF CENTER IN N SEMICIRCLE. THE HAZARDS 
AFFECTING LAND ARE... LIFE-THREATENING SURF AND RIP CURRENT 
CONDITIONS...HIGH-ENOUGH AMOUNTS OF RAIN THAT MAY CAUSE LIFE-
THREATENING FLASH FLOODS AND MUD SLIDES...AND THE TROPICAL STORM 
FORCE WINDS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...   
     
THE MONSOON TROUGH FROM 09N85W TO 09N90W TO 07N95W TO 
11N105W...THEN RESUMES FROM LOW PRES NEAR 16N112W 1008 MB...THE 
REMNANT LOW OF DALILA...TO BEYOND 06N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION OBSERVED FROM 02N TO 05N E OF 82W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION OBSERVED WITHIN 90 
NM N OF AXIS BETWEEN 100W AND 105W. 

...DISCUSSION... 

SUBSIDENT NE SHEAR ALOFT ASSOCIATED WITH AN UPPER ANTICYCLONE 
CENTER OVER E CENTRAL MEXICO NEAR 23N98W IS INHIBITING ORGANIZED 
CONVECTION BETWEEN 90W AND 110W. THE EXCEPTION IS ALONG THE 
MONSOON TROUGH BETWEEN 100W AND 105W WHERE SW FLOW INTO THE 
TROUGH IS ENCOUNTERING MODERATE NE FLOW. A SHARP UPPER TROUGH 
EXTENDS ALONG ROUGHLY 90W FROM GUATEMALA TO 06N92W...ALLOWING 
FAVORABLE CONDITIONS FOR CONVECTIVE DEVELOPMENT FARTHER EAST. 
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 EAST SIDE 
OF THE TROUGH WILL ALLOW CONVECTIVE DEVELOPMENT E OF 90W OVER 
THE NEXT COUPLE OF DAYS.

GULF OF CALIFORNIA...AN ASCAT PASS FROM 05 UTC INDICATED S WINDS 
TO 20 KT OVER THE SOUTHERN ENTRANCES TO THE GULF OF CALIFORNIA. 
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 AN UPPER ANTICYCLONE NEAR 15N135W 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 IN EXCESS 8 FT WILL CROSS THE EQUATOR 
TODAY BETWEEN 95W AND 115W...EVENTUALLY ENCOMPASSING THE AREA S 
10N E OF 120W TUE THIS SCENARIO WILL BRING THE POTENTIAL FOR 
ROUGH SURF TO EXPOSED AREAS OF COSTA RICA AND PANAMA BY LATE 
TUESDAY/EARLY WEDNESDAY.

$$ 
CHRISTENSEN