000
AXPZ20 KNHC 031525
TWDEP 

TROPICAL WEATHER DISCUSSION                                   
NWS NATIONAL HURRICANE CENTER MIAMI FL                       
1605 UTC SAT AUG 02 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...SPECIAL FEATURES...

MAJOR HURRICANE ISELLE CENTERED NEAR 15.5N 132.8W AT 03/1500 UTC 
OR ABOUT 1299 NM...2405 KM E OF HILO HAWAII MOVING WEST OR 280 
DEGREES AT 10 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 965 MB.  
ISELLE IS A CATEGORY THREE HURRICANE ON THE SAFFIR-SIMPSON 
HURRICANE WIND SCALE. MAXIMUM SUSTAINED WIND SPEED IS 100 KT 
WITH GUSTS TO 120 KT. NUMEROUS STRONG CONVECTION IS OBSERVED 
WITHIN 90 NM OF THE CENTER OF ISELLE. GIVEN THE STRONG WINDS BUT 
MODEST FORWARD SPEED OF ISELLE...SEAS ARE ESTIMATED TO BE NEAR 
35 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 NIGHT INTO EARLY WED. PLEASE SEE LATEST NHC 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/ WTPZ24 KNHC 
FOR MORE DETAILS.  

A 1007 MB LOW PRESSURE REMAINS EMBEDDED WITHIN THE MONSOON 
TROUGH NEAR 14N115W. FIRST-LIGHT VISIBLE IMAGERY SHOWS THAT THE 
LOW HAS A WELL-DEFINED CENTER AND CIRCULATION...BUT THE 
ASSOCIATED CONVECTION IS BEING DISPLACED TO THE WEST BY STRONG 
UPPER-LEVEL WINDS...AND THESE CONDITIONS ARE EXPECTED TO 
PROBABLY PERSIST FOR ANOTHER 24 HOURS. ENVIRONMENTAL CONDITIONS 
ARE FORECAST TO BECOME MORE CONDUCIVE FOR TROPICAL CYCLONE 
DEVELOPMENT...AND A TROPICAL DEPRESSION IS STILL EXPECTED TO 
FORM DURING THE NEXT DAY OR TWO WHILE THIS SYSTEM CONTINUE TO 
MOVE WESTWARD AT AROUND 10 KT.  
                           
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
             
THE MONSOON TROUGH EXTENDS FROM 10N85W TO 07N100W TO A 1007 MB 
LOW PRES LOCATED NEAR 14N115W. SCATTERED MODERATE IS FROM 05N TO 
08N BETWEEN 88W AND 92W. SIMILAR CONVECTION IS ALSO NOTED FROM 
05N TO 09N BETWEEN 103W AND 105W...AND FROM 10N TO 12N BETWEEN 
87W AND 93W. CLUSTERS OF MODERATE CONVECTION ARE SEEN WITHIN 90 
NM OF THE COAST OF MEXICO BETWEEN 99W AND 106W.

...DISCUSSION...

A BROAD UPPER ANTICYCLONIC CIRCULATION IS CENTERED NEAR 19N140W 
WITH A RIDGE EXTENDING E-NE TO ABOUT 125W. MODERATE TO STRONG 
UPPER LEVEL SUBSIDENCE AND IMPLIED DRY AIR MASS IS SEEN ON WATER 
VAPOR IMAGERY WITHIN THE RIDGE AXIS...PARTICULARLY N OF 20N W OF 
120W. AN UPPER-LEVEL TROUGH REMAINS E OF THE RIDGE AND EXTENDS 
FROM 31N117W TO 21N120W TO 17N122W. AN INVERTED TROUGH CONTINUES 
FROM THIS POINT TO NEAR 11N125W. ANOTHER UPPER ANTICYCLONE IS 
CENTERED NEAR 21N111W AND TO THE NE OF THE LOW PRES LOCATED NEAR 
14N115W. FARTHER EAST...AN UPPER CYCLONE IS SPINNING OVER THE 
FAR WESTERN CARIBBEAN AND THE YUCATAN PENINSULA...WITH A TROUGH 
EXTENDING SW TO NEAR 13N101W. A DIFFLUENT PATTERN ALOFT BETWEEN 
THIS UPPER LOW OVER AND AN UPPER ANTICYCLONE CENTERED N OF 
PANAMA IS ENHANCING CONVECTION E OF 95W. 
 
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 MAINLY S OF 
THE EQUATOR. SEAS TO 8 FT ARE EXPECTED AS FAR N AS 10N-11N 
BETWEEN 90W AND 100W BY TUE MORNING. SEAS GENERATED BY HURRICANE 
ISELLE WILL SPREAD OUT WELL AWAY FROM THE CENTER...IMPACTING THE 
WATERS FROM 10N-23N W OF 125W WITH BUILDING SEAS OF 8 TO 12 FT.
 
$$ 
GR