000
AXPZ20 KNHC 271004
TWDEP 

TROPICAL WEATHER DISCUSSION                                   
NWS NATIONAL HURRICANE CENTER MIAMI FL                       
1005 UTC SUN JUL 27 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0830 UTC.

...SPECIAL FEATURES...                                   

THE CENTER OF TROPICAL STORM HERNAN AT 27/0900 UTC IS NEAR 16.9N 
110.0W...OR ABOUT 360 NM TO THE SOUTH OF THE SOUTHERN TIP OF 
BAJA CALIFORNIA. HERNAN IS MOVING NORTHWESTWARD 12 KNOTS. THE 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 997 MB. THE MAXIMUM 
SUSTAINED WIND SPEEDS ARE 55 KNOTS WITH GUSTS TO 65 KNOTS. 
CONVECTIVE PRECIPITATION...NUMEROUS STRONG FROM 20N TO 22N 
BETWEEN 109W AND 111W...AND FROM 15N TO 19N BETWEEN 108W AND 
111W. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP3/WTPZ23 KNHC FOR MORE DETAILS. AN 
UPPER LEVEL RIDGE EXTENDS FROM 20N109W BEYOND 26N107W IN MEXICO. 
THIS RIDGE IS PROVIDING THE MIDDLE LEVEL TO UPPER LEVEL 
DIFFLUENT ATMOSPHERIC ENVIRONMENT FOR GRADUAL STRENGTHENING OF 
HERNAN THROUGH EARLY MONDAY. HERNAN IS FORECAST TO WEAKEN AFTER 
MONDAY DUE TO MOVEMENT ACROSS COOLER WATERS AND A STRONGLY 
SHEARED ENVIRONMENT.

THE CENTER OF TROPICAL DEPRESSION GENEVIEVE AT 27/0900 UTC IS 
NEAR 12.4N 140.1W...OR ABOUT 980 NM TO THE EAST-SOUTHEAST OF 
SOUTH POINT HAWAII. GENEVIEVE IS MOVING WESTWARD 8 KNOTS. THE 
ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB. THE MAXIMUM 
SUSTAINED WIND SPEEDS ARE 30 KNOTS WITH GUSTS TO 40 KNOTS. 
CONVECTIVE PRECIPITATION...SCATTERED STRONG FROM 08N TO 11N 
BETWEEN 137W AND 140W...AND FROM 10N TO 13N BETWEEN 136W AND 
140W. PLEASE READ THE LATEST NHC FORECAST/ADVISORY UNDER 
AWIPS/WMO HEADERS MIATCMEP2/WTPZ22 KNHC FOR MORE DETAILS.

A 1007 MB LOW PRESSURE CENTER IS NEAR 15N130W. CONVECTIVE 
PRECIPITATION...SCATTERED STRONG FROM 13N TO 15N BETWEEN 126W 
AND 129W. THE LOW LEVEL CIRCULATION REMAINS EXPOSED. UPPER LEVEL 
SOUTHWESTERLY WINDS ARE TO THE NORTHWEST OF THE SURFACE LOW 
PRESSURE CENTER...RELATED TO THE 32N132W 13N140W MIDDLE LEVEL TO 
UPPER LEVEL TROUGH. THE 1007 MB LOW PRESSURE CENTER WILL DRIFT 
WESTWARD...AND IT WILL BECOME IMPACTED BY THE UPPER LEVEL DRY 
AIR AND WIND SHEAR THAT AWAIT IT TO THE NORTHWEST. SOME TIME FOR 
TROPICAL CYCLONE DEVELOPMENT IS POSSIBLE. AN AREA OF FRESH TO 
STRONG WINDS WITH SEA HEIGHTS TO 10 FEET IS FORECAST WITH THIS 
SYSTEM DURING THE NEXT 48 HOURS.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
THE MONSOON TROUGH PASSES THROUGH 08N78W IN PANAMA...TO A 1011 
MB LOW PRESSURE CENTER THAT IS NEAR 07N97W...TO 10N105W. THE 
MONSOON TROUGH IS BROKEN UP BY TROPICAL STORM HERNAN. IT 
CONTINUES NEAR 12N111W TO A 1011 MB LOW PRESSURE CENTER THAT IS 
NEAR 10N120W...TO 12N125W. THE CYCLONIC WIND FLOW THAT IS MOVING 
AROUND A 1007 MB LOW PRESSURE CENTER THAT IS NEAR 15N130W BREAKS 
UP THE MONSOON TROUGH AGAIN. THE MONSOON TROUGH CONTINUES FROM 
THE 15N130W LOW PRESSURE CENTER TO 13N137W. CONVECTIVE 
PRECIPITATION...SCATTERED STRONG FROM 13N TO 15N BETWEEN 126W 
AND 129W. 
 
...DISCUSSION...                                                
AN UPPER LEVEL TROUGH PASSES THROUGH 32N132W TO 25N134W TO 
13N140W. COMPARATIVELY DRIER AIR IN SUBSIDENCE IS WITHIN 420 NM 
TO 480 NM ON EITHER SIDE OF THE TROUGH.

A SEPARATE MIDDLE LEVEL TO UPPER LEVEL CYCLONIC CIRCULATION 
CENTER IS NEAR 24N115W. CYCLONIC WIND FLOW IS WITHIN A RADIUS OF 
120 NM TO 180 NM AWAY FROM THE CENTER. 

A MIDDLE LEVEL TO UPPER LEVEL TROUGH IS ALONG 16N115W 09N114W 
03N112W. THIS TROUGH IS FROM 500 NM TO 600 NM TO THE SOUTHWEST 
OF TROPICAL STORM HERNAN.
 
THE GULF OF PAPAGAYO...NORTHEAST TO EAST WINDS ARE EXPECTED TO 
PULSE FROM THIS MORNING UNTIL EARLY THIS AFTERNOON...FROM 10N TO 
12N FROM 81W EASTWARD. THE WIND SPEEDS WILL REACH 20 TO 25 KNOTS 
AND 8 FOOT SEA HEIGHTS. 20 KNOT WINDS ALSO ARE POSSIBLE DURING 
THE LATE NIGHT/EARLY MORNING HOURS OF MONDAY...ENDING AROUND 
SUNRISE. 

A SURFACE RIDGE IS ALONG 15N121W TO 23N124W BEYOND 30N140W. THE 
PRESSURE GRADIENT THAT EXISTS BETWEEN THE SOUTHERN PERIPHERY OF 
THE RIDGE AND GENEVIEVE IS PRODUCING AN AREA OF FRESH TO STRONG 
WINDS FROM 11N TO 17N TO THE WEST OF 137W WITH SEAS TO 9 FEET. 
THESE MARINE CONDITIONS ARE FORECAST TO MOVE WESTWARD IN TANDEM 
WITH GENEVIEVE DURING THE NEXT 12 TO 24 HOURS.

$$ 
MT