000
AXPZ20 KNHC 030257
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
0405 UTC WED JUL 03 2013

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 
0315 UTC.

...SPECIAL FEATURES.. 
HURRICANE DALILA AT 18.3N 107.3W 987 MB AT 0300 UTC JUL 03 MOVE
W OR 270 DEGREES AT 02 KT.  MAXIMUM SUSTAINED WIND 65 GUSTS TO 80
KT.  UPPER LEVEL SHEAR HAS DIMINISHED AS UPPER LEVEL ANTICYCLONE
TAKES OVER ENVIRONMENT ALOFT.  STEERING OF DALILA HAS NOW BECOME
AN ISSUE SINCE ITS MOVEMENT HAS DIMINISHED TO ONLY 2 KT.  THIS
ALLOWS DALILA MORE TIME UNDER FAVORABLE CONDITIONS AND MAY DELAY
ITS WEAKENING PHASE AS IT WILL STAY OVER WARMER WATERS FOR
LONGER.  UPPER LEVEL ANALYSIS SHOW THE CYCLONE THAT WAS SHEARING
DALILA TO HAVE MOVED OUT W WHILE ANTICYCLONE HAS NOW SET OVER 
THE HURRICANE. NUMEROUS MODERATE TO STRONG CONVECTION WITHIN 120
NM N SEMICIRCLE...90 NM SW AND 60 SE QUADRANTS.  SEE LATEST 
FORECAST/ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP4/WTNT24 KNHC
FOR MORE DETAILS.

LOW PRES CENTER 1008 MB HAS FORMED JUST S OF GULF OF TEHUANTEPEC
AT 12.6N 94.8W.  LOW PRES EMBEDDED IN WARM MOIST TROPICAL AIR
MASS WITH VERY WARM SEA SURFACE TEMPERATURE AND HAS SHOWN GOOD
CYCLONIC TURNING.  MOST MODELS SPIN THIS LOW PRES INTO A TROPICAL
SYSTEM BY LATE WED AND THEIR MAIN DIFFERENCE LIES IN TIMING AND
INTENSITY OF SYSTEMS WITH AGREED W-NW DRIFT.  SCATTERED MODERATE
TO STRONG CONVECTION CURRENTLY OBSERVED WITHIN 180 NM NW AND 90
NM SE SEMICIRCLES.  SYSTEM EXPECTED TO STRENGTHEN OVER NEXT FEW
DAYS WITH 50 PERCENT POSSIBILITY OF TROPICAL CYCLONE FORMATION WITHIN
THE NEXT 48 HRS. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...   
MONSOON TROUGH AXIS FROM 10N86W TO LOW PRES 1008 MB AT 12N95W
TO 16N96W.  IT THEN RESUMES FROM 14N120W TO 09N130W THEN ITCZ
AXIS TO 08N135W TO BEYOND 09N140W.  SCATTERED MODERATE ISOLATED
STRONG CONVECTION N OF 08N E OF 87W AND WITHIN 90 NM S OF AXIS
W OF 124W.

...DISCUSSION...
WELL DEFINED DEEP LAYERED CYCLONE VERTICALLY STACKED AT 31N140W
WITH UPPER LEVEL TROUGH EXTENDING TO 22N137W TO 18N140W. 
ASSOCIATED SURFACE LOW PRES 1006 MB WITH COLD FRONT EXTENDING
FROM 32N137W TO 23N140W.  REINFORCING NW SURGE BRING FRESH TO
STRONG S-SE BREEZE WITH SEAS BUILDING TO 8-9 FT TO NW CO1RNER OF
BASIN E OF FRONT N OF 24N W OF 135W TONIGHT.

UPPER LEVEL SHORTWAVE SLIDING ALONG W SIDE OF LONGWAVE TROUGH 
OVER TEXAS AND EASTERN MEXICO BRINGS ADDITIONAL ENERGY TO LOW
PRES AT 12N94W ENHANCING ITS CHANCES OF TROPICAL ORGANIZATION.
SEE DISCUSSION UNDER SPECIAL FEATURES. 

...ELSEWHERE AT THE LOWER LEVELS...
CROSS EQUATORIAL SW SWELL BUILDS UP SEAS TO 8 FT S OF 03N W OF
96W WED...BUT START SUBSIDING LATE THU AND FRI. 

$$ 
WALLY BARNES