000
AXPZ20 KNHC 050313
TWDEP 

TROPICAL WEATHER DISCUSSION                                   
NWS NATIONAL HURRICANE CENTER MIAMI FL                       
0405 UTC MON AUG 04 2014

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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...SPECIAL FEATURES...

MAJOR HURRICANE ISELLE CENTERED NEAR 16.0N 138.0W AT 05/0300 UTC 
MOVING WEST OR 265 DEGREES AT 7 KT. ESTIMATED MINIMUM CENTRAL 
PRESSURE IS 951 MB. ISELLE IS A CATEGORY FOUR HURRICANE ON THE 
SAFFIR-SIMPSON HURRICANE WIND SCALE. MAXIMUM SUSTAINED WIND 
SPEED IS 115 KT WITH GUSTS TO 140 KT. NUMEROUS STRONG CONVECTION 
IS OBSERVED WITHIN 120 NM OF THE CENTER OF ISELLE. GIVEN THE 
STRONG WINDS AND MODEST FORWARD SPEED OF ISELLE...SEAS ARE 
ESTIMATED TO BE NEAR 40 FT IN THE NORTH CENTRAL PORTION OF THE 
STORM. THE OFFICIAL INTENSITY FORECAST CALLS FOR ISELLE TO 
MAINTAIN HURRICANE STATUS THROUGH TUE ACROSS THE FORECAST AREA. 
ISELLE IS FORECAST TO CROSS 140W TUE EVENING. PLEASE SEE LATEST 
NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTPZ24 
KNHC FOR MORE DETAILS.  

TROPICAL STORM JULIO IS CENTERED NEAR 13.5N 122.8W AT 05/0300 
UTC OR ABOUT 925 NM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA 
MOVING WEST OR 270 DEGREES AT 14 KT. ESTIMATED CENTRAL PRESSURE 
IS 1000 MB. MAXIMUM SUSTAINED WIND SPEED IS 50 KT WITH GUSTS TO 
60 KT. NUMEROUS MODERATE TO STRONG CONVECTION IS OBSERVED WITHIN 
180 NM IN THE W SEMICIRCLE OF THE CENTER. SCATTERED MODERATE TO 
STRONG WITHIN 120 NM E SEMICIRCLE. T.S. JULIO IS FORECAST TO 
INTENSIFY FURTHER TO HURRICANE STRENGTH BY TUE EVENING AS IT 
MOVES WEST ACROSS THE FORECAST AREA. PLEASE SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC 
FOR MORE DETAILS.  
                           
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

MONSOON TROUGH EXTENDS FROM 10N84W TO LOW PRES NEAR 10N97W 1010 
MB TO 08N102W TO 10N108W. SCATTERED MODERATE TO ISOLATED STRONG 
CONVECTION IS FROM 07N TO 12N BETWEEN 82W AND 86W...AND FROM 09N 
TO 12N BETWEEN 95W AND 99W.   
       
...DISCUSSION...

AN UPPER-LEVEL TROUGH IS OVER THE NW CORNER AND EXTENDS FROM A 
CUT-OFF LOW NEAR 35N126W TO BEYOND 24N140W. AN ANTICYCLONIC 
CIRCULATION IS CENTERED NEAR 21N121W WITH A RIDGE EXTENDING N-NE 
TO BAJA CALIFORNIA NEAR 28N114W. A SECOND ANTICYCLONE HAS 
DEVELOPED OVER N-CENTRAL MEXICO NEAR 27N105W. A GENERAL EASTERLY 
FLOW ALOFT IS NOTED S OF 20N W OF 110W. THE REMAINDER OF THE 
AREA E OF 110W IS UNDER THE INFLUENCE OF A RIDGE ANCHORED BY AN 
ANTICYCLONE LOCATED OFF THE COAST OF PERU NEAR 08S83W PRODUCING 
EASTERLY UPPER LEVEL WINDS FROM EQUATOR TO 15N E OF 110W. 
 
A SURFACE RIDGE IS N OF 20N. FAIRLY DRY CONDITIONS PERSIST 
ACROSS MOST OF THE AREA N OF 20N W OF 115W. A FAIRLY MOIST 
ENVIRONMENT IS TO THE SOUTH OF THE RIDGE DUE TO THE PRESENCE 
OF TROPICAL CYCLONES ISELLE AND JULIO.
 
LONG PERIOD SWLY SWELLS FROM THE SOUTHERN HEMISPHERE WILL 
CONTINUE TO IMPACT MAINLY THE WATERS E OF 110W...BUILDING SEAS 
TO AROUND 9 FT ACROSS THE SOUTH-CENTRAL WATERS BUT PARTICULARLY  
S OF THE EQUATOR. 

$$ 
FORMOSA