000
AXPZ20 KNHC 041500
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC MON APR 04 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 3N78W TO 00N100W TO 3N130W TO 2N140W. A SURFACE 
TROUGH IS EMBEDDED IN THE ITCZ AXIS...ANALYZED FROM 5N85W TO 
2N90W. SCATTERED MODERATE CONVECTION WAS WITHIN 110 NM ON EITHER 
SIDE OF THE TROUGH AXIS. ISOLATED WEAK CONVECTION IS WITHIN 
250-360 NM N OF THE ITCZ AXIS BETWEEN 95W AND 120W.

...DISCUSSION...

A BROAD MID-UPPER LEVEL CYCLONIC CIRCULATION IS OVER THE NW 
DISCUSSION AREA AND SUPPORTS A SURFACE TROUGH ANALYZED ALONG 
131W FROM 15N TO 25N. THIS FEATURE IS PRODUCING ISOLATED SHOWERS 
FROM 20N TO 28N BETWEEN 121W AND 131W. EARLIER ASCAT PASSES 
REVEALED WINDS AS HIGH AS 20 NM IN THE VICINITY OF THE TROUGH 
AXIS. THE BROAD UPPER LEVEL TURNING AROUND THE UPPER LOW IS ALSO 
MOVING HIGH DENSE CIRRUS CLOUDS FROM THE TROPICAL PACIFIC REGION 
TO THE WEST COAST OF MEXICO N OF 6N E OF 121W. THIS SYSTEM IS 
EXPECTED TO WEAKEN AS THE UPPER LOW LIFTS NORTHEASTWARD OVER THE 
NEXT FEW DAYS.

ANTICYCLONIC CIRCULATION ALOFT IS IN THE ERN TROPICAL PACIFIC 
NEAR 7N96W. ALSO...ANOTHER BROAD ANTICYCLONIC CIRCULATION ALOFT 
IS OVER THE N CENTRAL S AMERICA. THE COMBINATION OF THESE TWO 
UPPER FEATURES ARE PRODUCING AN AREA OF DIFFLUENCE ALOFT THAT 
SUPPORTS THE SURFACE TROUGH ANALYZED IN THE ITCZ FROM 5N85W TO 
2N90W.

A COLD FRONT IS FORECAST TO MOVE ACROSS THE SW GULF OF 
MEXICO...AND AS IT REACHES THE GULF OF TEHUANTEPEC...IT IS 
EXPECTED TO PRODUCE GALE FORCE WINDS WITHIN THE NEXT 36 HOURS. 
HOWEVER...THE EVENT IS EXPECTED TO BE SHORT...LASTING FROM TUE 
EVENING THROUGH WED MORNING.

$$
DGS/FG