000
AXPZ20 KNHC 051546
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JUL 04 2012

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 
1430 UTC.

...SPECIAL FEATURE... 
TROPICAL DEPRESSION FOUR-E IS UPGRADED TO TROPICAL STORM DANIEL 
OVER THE OPEN WATERS OF THE EASTERN NORTH PACIFIC AT 05/1500 
UTC. AT THIS TIME...IT IS CENTERED NEAR 14.2N 110.5W MOVING W-NW 
OR 285 DEGREES AT 10 KT. ESTIMATED MINIMUM CENTRAL PRES IS 1002 
MB. MAXIMUM SUSTAINED WIND SPEED IS 40 KT GUST TO 50 KT. SEA 
LATEST NHC FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/ 
WTPZ24 KNHC FOR MORE DETAILS. NUMEROUS STRONG CONVECTION IS 
NOTED WITHIN 90 NM NE AND 180 NM SW SEMICIRCLES. DANIEL IS 
FORECAST TO REMAIN A TROPICAL STORM AS IT MOVES W-NW TODAY 
FOLLOWED BY A TURN TOWARD THE WEST ON FRIDAY.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH IS OVER THE SW CARIBBEAN CROSSING CENTRAL 
COSTA RICA TO NEAR 08N93W THEN RESUMES AT 12N116W TO 09N125W. 
THE ITCZ IS FROM 09125W TO BEYOND 07N140W. A CLUSTER OF MODERATE 
TO STRONG CONVECTION IS FROM 03N TO 07N E OF 80W TO THE COAST OF 
COLOMBIA. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS NOTED 
FROM 05N TO 10N BETWEEN 80W AND 100W. SIMILAR CONVECTION IS ALSO 
SEEN FROM 10N TO 14N BETWEEN 100W AND 103W...AND FROM 07N TO 14N 
BETWEEN 116W AND 122W.

...DISCUSSION...
BROAD UPPER-LEVEL TROUGH COVERS THE AREA N OF 20N BETWEEN 
125-135W WITH AN UPPER-LEVEL RIDGE W OF THE TROUGH. AN UPPER 
LEVEL ANTICYCLONIC CIRCULATION IS CENTERED NEAR 18N114W WITH 
RIDGE FROM THE ANTICYCLONE SW TO 12N128W. ANOTHER RIDGE EXTENDS 
FROM THE SAME ANTICYCLONE TO THE NE TO NEAR LAS MARIAS ISLANDS.  
STRONG UPPER LEVEL SUBSIDENCE AND IMPLIED DRY AIR MASS IS N OF 
20N W OF 110W...INCLUDING BAJA CALIFORNIA PENINSULA AS EVIDENCE 
IN RECENT WATER VAPOR IMAGERY. A DIFFLUENT PATTERN ALOFT IS 
ENHANCING CONVECTION ALONG THE MONSOON TROUGH E OF 93W. 

HIGH PRESSURE 1029 MB LOCATED NW OF AREA NEAR 36N154W HAS RIDGE 
EXTENDING SE TO NEAR 22N118W. THE PRESSURE GRADIENT BETWEEN THIS 
RIDGE AND LOWER PRESSURE IN THE VICINITY OF THE ITCZ IS 
MAINTAINING A SMALL AREA OF FRESH 20 KT TRADES FROM 15N TO 20N W 
OF 130W. SCATTEROMETER DATA CONFIRMED THE PRESENCE OF THESE 
WINDS. THIS RIDGE WILL PERSIST OVER THE NEXT 48 HOURS WITH A 
SMALL AREA OF FRESH TRADES COVERING ROUGHLY FROM 11N-16N W OF 
130W IN ABOUT 24 HOURS...AND FROM 10N TO 15N W OF 135W IN 48 
HOURS. IN ADDITION...THE AERIAL EXTENT OF THE 20-33 KT WINDS 
ASSOCIATED WITH THE CIRCULATION OF DANIEL IS FORECAST TO EXPAND 
TO THE NW IN ABOUT 48 HOURS AS PRES GRADIENT TIGHTENS BETWEEN 
DANIEL AND THIS RIDGE OVER THE N WATERS.  

THE MONSOON TROUGH REMAINS ACTIVE E OF 93W. AN ELONGATED AREA OF 
SHOWER AND THUNDERSTORM ACTIVITY EMBEDDED IN THE MONSOON TROUGH 
REMAINS DISORGANIZED. ONLY GRADUAL DEVELOPMENT IS EXPECTED...AND 
THIS SYSTEM HAS A LOW CHANCE OF BECOMING A TROPICAL CYCLONE 
DURING THE NEXT 48 HOURS AS IT MOVES WESTWARD AT ABOUT 10 MPH.  
MODEL GUIDANCE ARE IN PRETTY GOOD AGREEMENT AND CONTINUE TO 
SLOWLY DEVELOP A SURFACE CIRCULATION IN THIS AREA OVER THE NEXT 
FEW DAYS...WITH A SPOT LOW NEAR 10N101W IN ABOUT 72 HOURS.

THE TROPICAL WAVE PREVIOUSLY LOCATED NEAR CENTRAL AMERICA WAS 
DROPPED FROM THE SURFACE MAP AT 1200 UTC BASED ON SCATTEROMETER 
DATA THAT CLEARLY SHOW THE WIND SHIFT ASSOCIATED WITH THE 
MONSOON TROUGH...NE WINDS N OF THE TROUGH AND SW WINDS S OF THE 
TROUGH AXIS.

ELY WINDS 20 KT WITH SEAS TO 8 FT CONTINUE ACROSS THE GULF OF 
PAPAGAYO AND ARE FORECAST TO INCREASE TO 20-25 KT BY FRI. NLY 
WINDS HAVE INCREASED TO 20-25 KT THROUGH THE GULF OF TEHUANTEPEC 
AND ARE EXPECTED TO CONTINUE THROUGH AT LEAST SAT. 

$$
GR