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Eastern Pacific Tropical Weather Discussion (Text)

000
AXPZ20 KNHC 251547
TWDEP 

TROPICAL WEATHER DISCUSSION                                    
NWS NATIONAL HURRICANE CENTER MIAMI FL                       
1605 UTC FRI JUL 25 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.

TROPICAL STORM GENEVIEVE CENTERED NEAR 12.3N 135.5W AT 25/1500 
MOVING WEST OR 270 DEGREES AT 9 KT. ESTIMATED MINIMUM CENTRAL 
PRESSURE IS 1004 MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KNOTS 
WITH GUSTS TO 50 KNOTS. NUMEROUS MODERATE TO STRONG CONVECTION 
IS NOTED WITHIN 120 NM E SEMICIRCLE OF LOW CENTER. LITTLE CHANGE 
IN STRENGTH IS FORECAST DURING THE NEXT 48 HOURS. PLEASE SEE 
LATEST NHC FORECAST/ADVISORY  UNDER AWIPS/WMO HEADERS MIATCMEP2/ 
WTPZ22 KNHC FOR MORE DETAILS.

AN AREA OF LOW PRES HAS DEVELOPED ALONG THE MONSOON TROUGH NEAR 
13.5N123.5W OR A LITTLE MORE THAN THOUSAND MILES SW OF THE 
SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA. THIS SYSTEM IS 
PRODUCING DISORGANIZED SHOWER ACTIVITY. THE LATEST NHC TROPICAL 
WEATHER OUTLOOK GIVES THIS LOW PRES AREA A MEDIUM CHANCE OF 
DEVELOPING INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS AS 
THE SYSTEM MOVES TOWARD THE W OR W-NW AT ABOUT 10 KT.

...TROPICAL WAVES...

A WEAK TROPICAL WAVE IS ALONG 112W FROM 10N TO 18N...MOVING WEST 
AT 15 KT. NO DEEP CONVECTION.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...            
MONSOON TROUGH EXTENDS FROM 07N78W TO 06N90W TO 07N100W TO 
10N112W TO A 1008 MB LOW PRESSURE NEAR 13.5N123.5W 12N132W. 
NUMEROUS MODERATE ISOLATED STRONG CONVECTION IS NOTED FROM 04N 
TO 07N BETWEEN 78W AND 82W. SCATTERED MODERATE ISOLATED STRONG 
CONVECTION IS WITHIN 210 NM N OF TROUGH BETWEEN 83W AND 85W. 
SIMILAR CONVECTION IS FROM 04N TO 07N BETWEEN 85W AND 90W.

...DISCUSSION...                                                

AN UPPER-LEVEL TROUGH REMAINS ACROSS THE NORTH-CENTRAL PORTION 
OF THE DISCUSSION AREA N OF 15N W OF 125W. THE MEAN AXIS EXTENDS 
FROM A CYCLONIC CIRCULATION NEAR 31N131W TO 18N136W. A BAND OF 
VERY STRONG UPPER-LEVEL WESTERLY WINDS NEAR THE BASE OF THIS 
TROUGH IS FORECAST TO IMPACT GENEVIEVE. THIS WILL RESULT IN 
SHEAR AND WEAKENING. MODERATE SUBSIDENCE WITH DRY AND STABLE AIR 
AT THE MIDDLE AND UPPER LEVELS IS OVER MUCH OF THE AREA N OF 20N 
W OF 125W. UPPER LEVEL DIFFLUENT FLOW IS ENHANCING CONVECTION 
ALONG THE MONSOON TROUGH MAINLY W OF 120W. A LARGE UPPER LEVEL 
ANTICYCLONIC CIRCULATION IS CENTERED OVER THE SW CONUS NEAR 
36N103W WITH THE ASSOCIATED RIDGE AXIS EXTENDING FROM THE 
ANTICYCLONE INTO THE E PACIFIC ACROSS NORTHERN MEXICO AND BAJA 
CALIFORNIA TO NEAR 27N118W. AN UPPER CYCLONIC CIRCULATION IS 
CENTERED NEAR 21N110W WITH A TROUGH EXTENDING SW TO NEAR 
17N114W. A DIFFLUENT PATTERN ALOFT AHEAD OF THE TROUGH AXIS IS 
HELPING TO INDUCE CONVECTION E OF 110W. UPPER LEVEL DIFFLUENT 
FLOW IS ALSO SUPPORTING CONVECTION IN ASSOCIATION WITH A LOW 
PRES LOCATED NEAR 11N103W. N TO NE FLOW ALOFT DOMINATES THE 
REMAINDER OF THE FORECAST REGION E OF 95W.

A LARGE BUT DISORGANIZED AREA OF SHOWERS AND TSTMS IS ASSOCIATED 
WITH A 1008 MB LOW PRES AREA LOCATED NEAR 11N103W. THIS 
CONVECTIVE ACTIVITY WAS PREVIOUSLY ASSOCIATED WITH A TROPICAL 
WAVE. UPPER-LEVEL WINDS ARE EXPECTED TO BECOME A LITTLE MORE 
FAVORABLE FOR THE DEVELOPMENT OF THIS SYSTEM OVER THE NEXT FEW 
DAYS AS IT MOVES W-NW AT 10-15 KT. THE LATEST NHC TROPICAL 
WEATHER OUTLOOK GIVES THIS LOW PRES AREA A LOW CHANCE OF 
DEVELOPING INTO A TROPICAL CYCLONE DURING THE NEXT 48 HOURS... 
AND A MEDIUM CHANGE THROUGH 5 DAYS. AN AREA OF FRESH TO STRONG 
WINDS WITHIN 90-120 NM NE QUADRANT OF THE LOW CENTER WITH SEAS 
TO 8-9 FT IS EXPECTED TO BE ASSOCIATED WITH THIS SYSTEM DURING 
THE NEXT 48 HOURS. 

GULF OF PAPAGAYO...STRONG TO NEAR GALE FORCE TRADE WINDS OVER 
THE SW CARIBBEAN WILL RESULT IN ANOTHER PULSE OF 20-25 KT WINDS 
THROUGH THE GULF OF PAPAGAYO OVERNIGHT TONIGHT INTO SAT MORNING. 
THESE WINDS WILL PULSE AGAIN SAT NIGHT INTO SUN MORNING. SEAS 
WILL BUILD TO 9 FT DURING EACH PULSE.   

GULF OF TEHUANTEPEC...ANOTHER PULSE OF NLY WINDS OF 20-25 KT IS 
EXPECTED TO BLOW THROUGH THE GULF OF TEHUANTEPEC TONIGHT INTO 
EARLY SAT. SEAS SHOULD MAXIMIZE AT AROUND 8 FT WITH THIS PULSE. 
AN ASCAT PASS SHOWED NLY WINDS OF 20-25 KT ACROSS THIS REGION 
EARLY THIS MORNING. 

OTHERWISE A SURFACE RIDGE DOMINATES THE REMAINDER OF THE AREA N 
OF 15N W OF 115W. PRES GRADIENT BETWEEN THE SOUTHERN PERIPHERY 
OF THE RIDGE AND GENEVIEVE IS PRODUCING AN AREA OF 20-25 KT 
TRADE WINDS FROM 16N TO 20N W OF 132W WITH SEAS TO 10 FT. THESE 
MARINE CONDITIONS ARE FORECAST TO MERGE WITH GENEVIEVE IN 
ABOUT 36-48 HOURS. 

$$ 
GR