000
AXPZ20 KNHC 151556
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU MAR 15 2007

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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 3N78W 4N98W 1N140W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION IS NOTED WITHIN 30 NM EITHER 
SIDE OF LINE 7N90W 3N101W AND LINE 4N124W 5N140W. SCATTERED 
MODERATE TO STRONG CONVECTION OBSERVED WITHIN 60 NM OF 8N109W.

...DISCUSSION...

AN UPPER CYCLONE IS CENTERED AT 22N135W WITH A TROUGH S TO A 
BASE NEAR 7N127W. DRY UPPER AIR WRAPS AROUND THE W SEMICIRCLE OF 
THE CYCLONE AND OVER THE DISCUSSION AREA W OF THE TROUGH AXIS. A 
BAND OF UPPER MOISTURE IS TRAPPED OVER THE NE SEMICIRCLE OF THE 
CYCLONE ROUGHLY WITHIN 90 NM EITHER SIDE OF LINE 24N134W 
22N121W. JUST TO THE N AND E OF THIS CYCLONE ARE SEVERAL OTHER 
CYCLONIC SWIRLS. ONE AT 30N137W AND ANOTHER AT 31N124W AND YET 
ANOTHER AT 30N117W. THE MODEL CONSENSUS HAS CHANGED SINCE 
YESTERDAY AND NOW SUGGESTS THAT THIS BROAD AREA OF UPPER LOW 
PRESSURE WILL CONSOLIDATE BRIEFLY TONIGHT AND EARLY FRI AND 
SHIFT NE LATE THEN FILL BY SAT AS UPPER RIDGING FURTHER S 
AMPLIFIES NORTHWARD. OTHERWISE...DRY UPPER AIR IS INDICATED N 
OF 15N W OF 120W.

THE DOMINATE FEATURE IN THE DEEP TROPICS IS A RIDGE EXTENDING W 
ACROSS S AMERICA ALONG 7N TO NEAR 11N110W. A MOISTURE PLUME... 
ORIGINATING FROM ITCZ CONVECTION BETWEEN 97W AND 117W...IS NOTED 
WITHIN N OF THE ITCZ TO 23N BETWEEN 120W AND 107W.

A STATIONARY INVERTED UPPER TROUGH IS NOTED OVER THE TROPICAL E 
PAC S OF 7N ALONG 8AW. THE UPPER FLOW IS DIFFLUENT S OF 7N E OF 
103W WITH SLIGHT ENHANCEMENT OF THE NORTHERN HEMISPHERE ITCZ.

AT THE LOW LEVELS...SURFACE HIGH PRES IS CENTERED NEAR 35N130W 
WITH A RIDGE SE TO 16N102W.

GAP WINDS...GULF OF TEHUANTEPEC NLY WINDS WILL BEGIN TO 
INCREASE TO 20 KT JUST AFTER SUNSET FRI AND INCREASE TO MINIMAL 
GALE BY MIDNIGHT AND A STRONG GALE SAT. NE WINDS 15 TO 20 KT 
CONTINUE IN AND DOWNSTREAM OF THE GULF OF PAPAGAYO. NLY WINDS 
MOSTLY 15 KT IN THE GULF OF PANAMA. 

$$
NELSON