000
AXPZ20 KNHC 120936
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JUN 12 2011

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 
0900 UTC.
 
...SPECIAL FEATURE...
ADRIAN IS DOWNGRADED TO A TROPICAL DEPRESSION AT 12/0900 UTC. 
AT THIS TIME...IT IS CENTERED NEAR 16.1N 114.8W MOVING W OR 275 
DEGREES AT 10 KT. MAXIMUM SUSTAINED WIND SPEED IS ESTIMATED TO 
BE 30 KT WITH GUSTS TO 40 KT. ESTIMATED MINIMUM CENTRAL PRESSURE 
IS 1004 MB. SEE THE LATEST NHC ADVISORY UNDER AWIPS/WMO HEADERS 
MIATCPEP1/WTPZ21 KNHC FOR MORE DETAILS. ADRIAN CONTINUES TO 
WEAKEN. NEARLY ALL OF THE DEEP CONVECTION DIMINISHED AROUND 0400 
UTC...BUT NOW A SMALL BURST OF CONVECTION HAS DEVELOPED TO THE E 
OF THE CENTER. THE O422 UTC REVEALED MAXIMUM WINDS NEAR 35 KT 
OVER THE NW QUADRANT. HOSTILE ENVIRONMENTAL CONDITIONS SHOULD 
CAUSE ADRIAN TO BECOME A REMNANT LOW LATER TODAY...AND DISSIPATE 
WITHIN A FEW DAYS.

...ITCZ/MONSOON TROUGH...
THE MONSOON TROUGH REMAINS FRAGMENTED AS A RESULT OF TROPICAL 
CYCLONE ADRIAN. ONE FRAGMENT OF THE MONSOON TROUGH EXTENDS FROM 
10N85W TO 11N89W TO 06N101W. THE SECOND FRAGMENT EXTENDS FROM 
11N116W TO 05N127W WITH THE INTERTROPICAL CONVERGENCE ZONE 
EXTENDING FROM 05N127W TO 04N140W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION IS NEAR 07N100W. SCATTERED MODERATE 
CONVECTION IS FROM 07N TO 09N BETWEEN 115W AND 117W.
 
...DISCUSSION...

AN UPPER LEVEL TROUGH ENTERS THE FORECAST AREA NEAR 30N118W THEN 
CONTINUES SW TO NEAR 25N126W AND W-NW TO 27N140W. AN 
ANTICYCLONIC CIRCULATION CENTERED NEAR 09N130W HAS A RIDGE 
COVERING THE WATERS S OF 20N W OF 120W. ANOTHER UPPER LEVEL 
TROUGH IS NOTED JUST E OF THE RIDGE ALONG 118W. SW FLOW AHEAD OF 
THIS TROUGH IS IMPACTING TROPICAL CYCLONE ADRIAN. AN UPPER 
ANTICYCLONE CONTINUES TO MEANDER OVER THE CENTRAL CARIBBEAN... 
CURRENTLY OVER HISPANIOLA...WITH A RIDGE EXTENDING SW ACROSS 
CENTRAL AMERICA INTO THE EPAC COVERING MOST OF THE AREA E OF 
90W. AN UPPER-LEVEL TROUGH REMAINS OVER THE GULF OF MEXICO. THE 
BASE OF THIS TROUGH IS OVER THE GULF OF TEHUANTEPEC. 
 
AT THE SURFACE...HIGH PRESSURE CENTERED NW OF THE AREA EXTENDS A 
RIDGE SE OVER THE FORECAST WATERS TO NEAR 23N115W. THE PRESSURE 
GRADIENT BETWEEN THE RIDGE AND LOWER PRES OVER MEXICO IS 
SUPPORTING FRESH 20 KT N WINDS N OF 24N E OF 120W. THE 0424 
ASCAT PASS AND A FEW SHIP OBSERVATIONS CORROBORATED THESE WIND 
SPEEDS. THE PRESSURE GRADIENT BETWEEN THE RIDGE AND LOWER 
PRESSURES ASSOCIATED WITH THE MONSOON TROUGH AND ITCZ IS 
MAINTAINING FRESH TRADE WINDS FROM 08N TO 22N W OF 130W AS SEEN 
ON THE MOST RECENT WINDSAT PASS. 

SOUTHERLY CROSS EQUATORIAL S TO SW SWELL EXTENDS NORTHWARD OVER 
MOST OF THE PACIFIC WATERS E OF 130W...MIXING WITH THE CONFUSED 
SEAS SURROUNDING THE TROPICAL CYCLONE. SE CROSS EQUATORIAL SWELL 
IS NOTED OVER THE DEEP TROPICS TO THE W OF 130W...MIXING WITH NE 
SWELL ASSOCIATED WITH THE TRADE WINDS S OF THE LOW LEVEL RIDGE.

$$
GR