000
AXPZ20 KNHC 131542
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED APR 13 2011

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.

...ITCZ...
AXIS IS ALONG 5N105W 2N120W 1N140W. SCATTERED MODERATE ISOLATED 
STRONG WITHIN 150 NM N OF AXIS FROM 122W TO 130W.

...DISCUSSION...
UPPER LEVEL RIDGE ACROSS THE FAR NW PORTION OF THE DISCUSSION 
AREA EXTENDS FROM 32N137W TO 15N140W. MODERATE TO STRONG 
SUBSIDENCE WITH DRY STABLE AIR AT THE MIDDLE AND UPPER LEVELS OF 
THE ATMOSPHERE COVERS THE AREA FROM 15N-30NW OF 125W. DOWNSTREAM 
UPPER LEVEL TROUGH WITH AXIS FROM 32N120W TO 22N128W. A 95-100 
KT JETSTREAM IS SE OF THE TROUGH AXIS FROM 26N118W ACROSS 
NORTHERN BAJA CALIFORNIA INTO THE SW UNITED STATES. SW WINDS 
AHEAD OF THE TROUGH IS ADVECTING HIGH LEVEL MOISTURE FROM ITCZ 
CONVECTION TOWARD SOUTHERN BAJA CALIFORNIA INTO NW MEXICO.

A LARGE UPPER LEVEL ANTICYCLONIC CIRCULATION OVER S CENTRAL 
MEXICO NEAR MEXICO CITY. WITH THE EXCEPTION OF A FEW SHOWERS S 
OF THE GULF OF TEHUANTEPEC MODERATE TO STRONG SUBSIDENCE COVERS 
THE AREA N OF 6N E OF 105W. ANTICYCLONIC FLOW IS ACROSS THE AREA 
E OF 15W.

SURFACE 1029 MB HIGH PRES IS CENTERED NEAR 31N136W WITH RIDGE 
FROM THE HIGH TO 15N113W. NE TRADES AROUND THE SOUTHERN 
PERIPHERY OF THE RIDGE 20-25 KT FROM 5N-25N W OF 125W. SURFACE 
TROUGH WITH AXIS ALONG 140W WITH NUMEROUS MODERATE TO STRONG 
CONVECTION FROM 3N-8N W OF 130W. A 1010 MB LOW PRES IS ANALYZED 
NEAR 2N101W. SCATTERED SHOWERS ARE WITHIN 150 NM E OF THE LOW. 
ANOTHER 1010 MB LOW IS CENTERED NEAR 8N105W...WITH TROUGH FROM 
THE LOW N TO 12N107W. SCATTERED STRONG TSTMS ARE WITHIN A 60 NM 
RADIUS OF 11N108W.

ELY WINDS TO 20 KT ARE BLOWING THROUGH THE GULF OF PAPAGAYO ARE 
EXPECTED TO DECEASE TO BELOW 20 KT BY THU AFTERNOON. NLY WINDS 
TO 20 KT ARE ALSO BLOWING THROUGH THE GULF OF TEHUANTEPEC 
HOWEVER THE PRES GRADIENT IS EXPECTED TO RELAX AND THE WIND WILL 
DECREASE TO LESS THAN 20 KT THIS EVENING.

$$
DGS