000
AXPZ20 KNHC 302157
TWDEP 

TROPICAL WEATHER DISCUSSION                                     
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1605 UTC SUN JUN 30 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...SPECIAL FEATURE... 
TROPICAL STORM DALILA AT 16.2N 103.7W WITH MINIMUM CENTRAL PRES
1003 MB MOVE N-NW AT 8 KT. SYSTEM REMAINS UNDER A PERSISTENT
S-SE WIND SHEAR THAT MAY BE CURTAILING ITS PREVIOUSLY EXPECTED 
INTENSIFICATION.  ON THE OTHER HAND...LOW LEVEL ENVIRONMENT 
CONTINUES FAVORABLE FOR DEVELOPMENT AS A MOIST WARM TROPICAL AIR 
MASS SURROUNDS DALILA AND SEA TEMPERATURES ARE ABOVE 28 C DEG.
DALILA IS BY COMPARISON A SMALL STORM IN SIZE BUT EXPECTED TO
INTENSIFY SLOWLY TONIGHT AND MON AS IT APPROACHES THE COAST OF
MEXICO THEN TURN NW PARALLEL TO THE COAST MON AND FINALLY TURN
W ALONG 19N AWAY FROM LAND MON NIGHT.  

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
MONSOON TROUGH AXIS EXTENDS FROM 14N127W TO 12N121W THEN ITCZ
TO 12N131W TO BEYOND 09N140W.  SCATTERED MODERATE CONVECTION
WITHIN 120 NM S OF AXIS E OF 108W AND WITHIN 150 NM OF AXIS 
FROM 129W TO 135W.

...DISCUSSION...
PERSISTENT UPPER LEVEL CYCLONE JUST NW OF TROPICAL STORM DALILA 
DRIFTING W SLOWER THAN PREVIOUSLY EXPECTED ALLOWING A STRONGER
SOUTHERLY SHEAR OVER STORM.  THIS MAY HAVE CURTAILED DALILA'S
INTENSIFICATION...OR AT LEAST DELAYED IT BY NOT ALLOWING THE
ASSOCIATED ANTICYCLONE TO PERFORM ITS OUTFLOWING TASKS.  ON THE
OTHER HAND...ANTICYCLONE ALLOWS ABUNDANT AMOUNT OF WARM AND
MOIST TROPICAL AIR MASS TO SURROUND DALILA AND SUPPLY ITS ENERGY
IN CONJUNCTION WITH THE WARM SEA SURFACE TEMPERATURES.  

FURTHER W...LARGE AMPLITUDE UPPER LEVEL LONGWAVE TROUGH EXTEND
FROM WELL DEFINED CYCLONE WELL N OF AREA TO 32N142W.  ASSOCIATED
COLD FRONT EXPECTED TO ENTER E PAC BUT STALL AS CYCLONE SHIFT NE
AND PULLS SUPPORT FROM FRONT.

...ELSEWHERE AT THE LOWER LEVELS...
HIGH PRES CENTER 1019 MB AT 34N133W FORCES REMNANTS OF COSME 
OUT OF AREA AND WEAKENS BUT HOLD POSITION AS STALLING COLD 
FRONT DISSIPATES TO ITS NW.  ONLY LINGERING EFFECTS EXPECTED
ARE 8-9 FT N OF 20N W OF 134W TO SUBSIDE LATE TONIGHT.

$$
WALLY BARNES