000
AXPZ20 KNHC 142210
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU AUG 14 2008

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 
2130 UTC.

...SPECIAL FEATURE...

TROPICAL STORM ISELLE AT 17.8N 110.2W 1002 MB AT 2100 UTC MOVING 
W NW OR 300 DEG AT 07 KT. MAXIMUM SUSTAINED WINDS 40 GUSTS TO 50 
KT. MODERATE TO STRONG CONVECTION IS NOTED WITHIN 150 NM SW 
SEMICIRCLE. ISELLE IS FORECAST TO REMAIN A TROPICAL STORM FOR 
THE NEXT 2 DAYS AND THEN WEAKEN AS IT MOVES OVER COOLER WATERS. 
SEE THE LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADER 
MIATCMEP5/WTPZ25 KNHC FOR MORE DETAILS.

...TROPICAL LOWS...

LOW PRES IS ANALYZED AT 15N120W AT 1010 MB. THIS LOW HAS BEEN 
MOVING W NW AT 07 KT OVER THE PAST 24 HOURS BUT HAS BEGUN TO 
SLOW ITS FORWARD SPEED AND TAKE A MORE NW TURN. NUMEROUS STRONG 
CONVECTION NOTED WITHIN 180 NM SW QUADRANT.  THERE IS CURRENTLY 
LITTLE CONVECTION ASSOCIATED WITH THIS LOW. THIS LOW HAS THE 
POTENTIAL TO DEVELOP INTO A TROPICAL CYCLONE OVER THE NEXT FEW 
DAYS.

REMNANT LOW PRES OF HERNAN IS CENTERED NEAR 16N141W AND 
ESTIMATED AT 1011. IT HAS MOVED SW AT 10 KT OVER THE PAST 24 
HOURS. WHILE THE LOW CENTER HAS MOVED OUT OF FORECAST WATERS...A 
QUIKSCAT PASS AT 1522 UTC SHOWS WINDS 20 TO 25 KT OUT TO 360 NM 
NW QUADRANT. THE CONDITIONS ASSOCIATED WITH THIS REMNANT LOW ARE 
EXPECTED TO MOVE W OF THE AREA IN THE NEXT 36 HOURS. 

...TROPICAL WAVES... 

A TROPICAL WAVE IS ALONG 103W AT THE MOMENT AND HAS BEEN MOVING 
W AT ABOUT 15 KT THE PAST 24 HOURS. SCATTERED MODERATE 
CONVECTION IS NOTED WITHIN 120 NM OF THE WAVE AXIS FROM 07N TO 
11N.

A TROPICAL WAVE IS ALONG 92W AND HAS BEEN MOVING W AT ABOUT 17 
KT THE PAST 24 HOURS. SCATTERED MODERATE CONVECTION IS NOTED 
WITHIN 150 NM W OF THE AXIS FROM 06N TO 09N AND WITHIN 60 NM OF 
AXIS FROM 11N TO THE COAST OF CENTRAL AMERICA.

...ITCZ...

THE ITCZ AXIS LIES FROM 07N79W TO 11N90W TO 12N105W TO 10N130W 
TO 11N140W. SCATTERED MODERATE CONVECTION IS NOTED WITHIN 210 NM 
N OF AXIS FROM 104W TO 115W. SCATTERED MODERATE TO ISOLATED 
STRONG CAN BE FOUND WITHIN 390 NM S OF AXIS BETWEEN 83W AND 88W.


...DISCUSSION...

THE UPPER LEVEL TROUGH OVER THE NW WATERS IS FORCING THE UPPER 
LEVEL LOW NEAR 27N120W N AT THIS TIME.  THIS TROUGH WILL 
CONTINUE TO FORCE THE RIDGE AXIS TO ITS S FARTHER S...KEEPING 
THE REMNANT OF LOW OF HERNAN ON A S OF W TRACK INTO THE CENTRAL 
PACIFIC. THE TROUGH IS EXPECTED TO SHED SOME SHORTWAVE ENERGY 
ALONG 135W OVER THE NEXT 24 HOURS. THIS SHOULD HELP MAINTAIN THE 
MEAN UPPER TROUGH IN THAT REGION SEPARATING THE ANTICYCLONES 
NEAR 20N141W AND OVER NW MEXICO. UPPER LEVEL DIFFLUENCE ON THE 
SW EDGE OF THE MEXICAN ANTICYCLONE WILL HELP MAINTAIN THE 
CONVECTION ASSOCIATED WITH THE LOW PRESSURE SYSTEM NEAR 14N120W 
AS IT MOVES W OVER THE NEXT 24 HOURS.  

THE TROPICAL WAVES TRACKING S OF THE ANTICYCLONE OVER MEXICO 
WILL TRANSPORT DEEP TROPICAL MOISTURE W NW. UPPER LEVEL 
DIFFLUENCE WILL BE MORE PREVALENT WITH THE FARTHER W TROPICAL 
WAVE. IN TURN...CONVECTION IS MORE LIKELY WITH THIS SYSTEM OVER 
THE NEXT DAY OR TWO AS LONG AS IT STAYS OVER WARM WATERS

STRONG E TO NE UPPER FLOW THROUGH SOUTHERN MEXICO AND MUCH OF 
CENTRAL AMERICA WILL KEEP HELP PUSH DEBRIS FROM AFTERNOON TSTMS 
OVER LAND W TOWARD THE COAST. NE FLOW ALOFT CONTINUES W OVER THE 
DISCUSSION AREA S OF 13N PUSHING DEBRIS MOISTURE SW TO THE 
EQUATOR E OF 125W. 

$$
SCHAUER CLARK