000
AXPZ20 KNHC 171559
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUN 17 2010

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
1500 UTC.

...SPECIAL FEATURES....
THE LOW PRES THAT WAS NEAR 15N106W EARLY THIS MORNING WAS 
UPGRADED TO TROPICAL DEPRESSION THREE-E AT 1500 UTC...AND TO 
TROPICAL STORM BLAS AT 1140 UTC. DATA RECENTLY RECEIVED FROM A 
SHIP INDICATE THAT TROPICAL DEPRESSION THREE-E HAS STRENGTHENED 
INTO TROPICAL STORM BLAS WHICH IS LOCATED NEAR 15.3N 105.3W 
MOVING NE OR 035 DEG AT 2 KT. ESTIMATED MINIMUM CENTRAL PRESSURE 
IS 1002 MB. MAXIMUM SUSTAINED WIND SPEED IS 35 KT WITH HIGHER 
GUSTS. SEE LATEST NHC PUBLIC ADVISORY UNDER AWIPS /WMO HEADERS 
MIATCPEP3/ WTPZ23 KNHC FOR MORE DETAILS. NUMEROUS MODERATE TO 
STRONG CONVECTION IS NOTED WITHIN 150 NM SW QUADRANT OF BLAS.

AT 17/1500 UTC...THE LAST ADVISORY OF TROPICAL DEPRESSION TWO-E 
WAS ISSUED BY THE NATIONAL HURRICANE CENTER. AT THIS TIME...THE 
TROPICAL DEPRESSION WAS LOCATED NEAR 15.8N 98.6W MOVING W-NW OR 
285 DEG AT 9 KT. ESTIMATED MINIMUM CENTRAL PRESSURE IS 1008 MB. 
MAXIMUM SUSTAINED WIND SPEED IS 25 KT WITH GUSTS TO 35 KT. SEE 
LATEST NHC PUBLIC ADVISORY UNDER AWIPS /WMO HEADERS MIATCPEP2/ 
WTPZ22 KNHC FOR MORE DETAILS. SCATTERED MODERATE TO STRONG 
WITHIN 200 NM W SEMICIRCLE AND SCATTERED MODERATE WITHIN 80 NM 
SE QUADRANT. SIMILAR CONVECTION IS FROM 11N TO 14N BETWEEN 96W 
AND 99W. REMNANT MOISTURE AND SOUTHWESTERLY ONSHORE FLOW COULD 
PRODUCE LOCALLY HEAVY RAINFALL ALONG PORTIONS OF THE SOUTHERN 
COAST OF MEXICO DURING THE NEXT COUPLE OF DAYS.

...TROPICAL WAVE...

A TROPICAL WAVE IS ALONG 92W N OF 06N EXTENDING NORTHWARD OVER 
GUATEMALA. THE SYSTEM IS MOVING W AT NEAR 10 KT. SCATTERED 
MODERATE CONVECTION IS WITHIN 120 NM W OF AXIS.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE IS CENTERED ALONG 08N82W TO 
11N91W THEN RESUMES FROM 12N104W TO 08N125W TO 07N140W. 
SCATTERED MODERATE IS WITHIN 60 NM EITHER SIDE OF AXIS W OF 
137W...AND NEAR 08N128W. 

...DISCUSSION...

W OF 110W...
A MID TO UPPER LEVEL TROUGH ENTERS THE FORECAST AREA NEAR 
30N120W AND EXTENDS TO AN ELONGATED UPPER LEVEL LOW LOCATED NEAR 
13N128W THEN CONTINUES SW TO 09N134W. TO THE W...AN UPPER LEVEL 
RIDGE LIES FROM 15N140W TO A CREST 26N135W WITH A 50-70 KT 
WEST-SOUTHWESTERLY JET TO ITS N. THIS JET LIES ON THE E SIDE OF 
A POSITIVELY TILTED UPPER TROUGH N OF HAWAII. AT THE SURFACE...A 
1039 MB SURFACE HIGH IS WELL N OF THE AREA NEAR 41N145W AND 
EXTENDS A RIDGE THROUGH 30N130W TO 15N122W. THE PRES GRADIENT 
BETWEEN THIS RIDGE AND THE COLD FRONT OVER THE WESTERN U.S. IS 
INDUCING 20 KT WINDS IN N WATERS WHILE A WEAKNESS IN THE SURFACE 
RIDGING OVER W WATERS CAUSED BY THE MID TO UPPER LEVEL TROUGHING 
N OF HAWAII HAS ALSO BROUGHT WINDS TO 20 KT. THE UPPER TROUGH 
OVER THE WESTERN U.S. WILL TURN NEGATIVE TILT AND CARRY THE COLD 
FRONT OUT OF THE AREA...REDUCING THE PRES GRADIENT BRIEFLY 
BEFORE A BATCH OF SHORTWAVE ENERGY FROM THE UPPER TROUGH N OF 
HAWAII SHIFTS E INTO THE WESTERN U.S. MEAN TROUGH AND AGAIN 
DEEPENS THE SURFACE TROUGHING IN THE WESTERN U.S.. AS A 
RESULT...THE AREA OF 20 KT WINDS WILL SHIFT INTO NE WATERS BY 
THE WEEKEND...INCLUDING WITHIN 150 NM W OF BAJA CALIFORNIA N OF 
25N. 

WATER VAPOR IMAGERY SHOWS ABUNDANT MODERATE SUBSIDENCE LEADING 
TO STABLE ENVIRONMENTAL CONDITIONS THROUGHOUT THE AREA N OF 20N 
AND FROM 10N TO 20N W OF 115W WHERE PATCHES OF OVERCAST TO 
BROKEN STRATOCUMULUS CLOUDS ARE NOTED. 

FRESH TRADE WINDS ARE LIMITED TO A REGION N OF THE ITCZ TO 14N W 
OF 130W. THIS AREA IS EXPECTED TO GRADUALLY SHRINK THROUGH FRI 
MORNING WITH LITTLE CHANGE EXPECTED THEN THROUGH SAT MORNING. 

E OF 110W...
DIFFLUENT UPPER FLOW SHOULD REMAIN OVER THE GULF OF TEHUANTEPEC 
THROUGH THU NIGHT AS A BROAD CYCLONIC GYRE IN THE LOW TO MID 
LEVELS CONTINUES OFF THE S COAST OF MEXICO. A DEEP LAYER 
MOISTURE MAX LIES BETWEEN TWO-E AND BLAS.

CROSS EQUATORIAL SW SWELL HAS ARRIVED ALONG THE COAST OF PANAMA 
AND COSTA RICA WITH SEAS WITH OFFSHORE WAVES IN THE 6-8 FT RANGE 
WITH 14-16 SECOND PERIODS. THIS SWELL WILL DAMPEN OUT AS IT 
STRETCHES N ALONG THE COAST OF CENTRAL AMERICA THU INTO FRI AND 
TO SOUTHERN BAJA CALIFORNIA BY SAT MORNING.

$$
GR/JS