000
AXPZ20 KNHC 070328
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC SUN MAR 07 2010

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

BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0300 UTC.

...ITCZ...
THE ITCZ AXIS IS ALONG 02N78W TO 06N100W TO 06N120W TO 04N130W 
TO 02N140W. SCATTERED MODERATE WITHIN 80 NM EITHER SIDE OF AXIS 
FROM 97W TO 102W AND FROM 04N TO 08N BETWEEN 106 AND 120W. 

...DISCUSSION...
A DEEP LAYER UPPER LEVEL-TROUGH EXTENDS FROM A STRONG CYCLONIC 
CIRCULATION ALONG THE COAST OF CALIFORNIA NEAR 35N121W TO 
24N121W. THESE UPPER-LEVEL FEATURES ARE PROVIDING SUPPORT FOR A 
COLD FRONT THAT PRESENTLY EXTENDS FROM 30N117W TO 23N127W. THE 
EDGE OF AN 1812 HIGH RESOLUTION ASCAT PASS CAPTURED AN AREA OF N 
WINDS 30 KT WITHIN NEAR 300 NM W OF 1007 MB LOW PRES LOCATED 
NEAR 30N124W. A FRONTAL TROUGH OR REINFORCING COLD FRONT EXTENDS 
FROM THIS LOW TO 28N122W TO 25N127W. SHIP MZFC6 LOCATED NEAR 
27N124W REPORTED 33 KT AT 2330 UTC WHILE ANOTHER SHIP JUST N OF 
AREA NEAR 31.5N126W REPORTED 39 KT. ALL THIS DATA CONFIRMED THE 
EXISTENCE OF STRONG TO MINIMAL GALE FORCE WINDS OVER FORECAST 
WATERS BEHIND THE REINFORCING COLD FRONT. WINDS ARE ALSO 
EXPECTED TO INCREASE ACROSS THE N PORTION OF THE GULF OF 
CALIFORNIA AS THE COLD FRONT CONTINUES TO APPROACH TO NORTHERN 
BAJA PENINSULA TONIGHT. THE GALE WARNING WILL REMAIN IN EFFECT 
THROUGH EARLY SUN MORNING. 

A BROAD UPPER-LEVEL RIDGE IS TO THE EAST OF THIS TROUGH WITH 
AXIS ALONG 98W AND DOMINATES PARTS OF NORTHERN MEXICO AND THE SW 
CONUS. SATELLITE DERIVED WINDS INDICATED A BRANCH OF THE 
SUBTROPICAL JET WITH CORE JET SPEEDS OF 90-110 KT CURVING 
ANTICYCLONICALLY ACROSS THE N PERIPHERY OF THE RIDGE. THE JET 
ENTERS THE AREA NEAR 22N140W AND TURNS NE ACROSS SOUTHERN BAJA 
CALIFORNIA AND NW MEXICO...WHERE WINDS INCREASE TO 150 KT INTO 
NEW MEXICO AND TEXAS. THIS JET IS TRANSPORTING ABUNDANT MID AND 
UPPER LEVEL MOISTURE ACROSS SOUTHERN BAJA CALIFORNIA AND MEXICO. 

IN THE DEEP TROPICS...A STABLE PATTERN REMAINS WITH AN EAST TO 
WEST UPPER LEVEL RIDGE EXTENDING FROM COLOMBIA ACROSS PANAMA AND 
COSTA RICA TO NEAR 7N102W. THIS RIDGE COVERS SE MEXICO AND 
CENTRAL AMERICA AND IS HELPING TO INDUCE SCATTERED MODERATE 
CONVECTION ALONG THE ITCZ. ANOTHER RIDGE DOMINATES THE SW 
PORTION OF THE FORECAST AREA WITH AN UPPER-LEVEL TROUGH IN 
BETWEEN. THE UPPER LEVEL TROUGH IS ALONG 104W EXTENDING S OF 10N 
TO THE EQUATOR. THE SECOND RIDGE IS ALSO FAVORING THE 
DEVELOPMENT OF SOME CONVECTION ALONG THE ITCZ AXIS BETWEEN 106W 
AND 120W.

AT THE SURFACE...A RIDGE OF HIGH PRESSURE DOMINATES THE AREA N 
OF 15N AND W OF 110W. A BROAD SWATH OF NE TO E TRADES OF 20 TO 
25 KT IS NOTED ON THE SOUTHERN PERIPHERY OF THE RIDGE. A MUCH 
EARLIER WINDSAT PASS AND A 1814 UTC ASCAT PASS CONFIRMED THE 
PRESENCE OF THE TRADE WINDS. THE RIDGE WILL CONTINUE TO BUILD 
EWD IN THE WAKE OF THE ABOVE MENTIONED COLD FRONT AND THE AREA 
OF TRADE WINDS WILL ALSO EXPAND EWD REACHING 110W IN ABOUT 24 TO 
36 HOURS. 

MARINE CONDITIONS CONTINUE TO BE DOMINATED BY LONG PERIOD... 
15-16 SECONDS...NW SWELLS WITH SEA HEIGHTS OF UP TO 12 FT.  
ANOTHER SET OF NW SWELL IS SPREADING ACROSS THE N WATERS IN THE 
WAKE OF THE AFOREMENTIONED COLD FRONT. THIS SWELL EVENT WILL 
ALSO PROPAGATE SE ACROSS THE REGIONAL WATERS MERGING WITH THE 
WIND WAVES GENERATING BY THE TRADES. 

GAP WINDS...
FRESH TO STRONG WINDS ACROSS THE GULF OF TEHUANTEPEC...GULF OF 
PAPAGAYO AND GULF OF PANAMA ARE FORECAST TO PERSIST THROUGH THE 
NEXT FEW DAYS AS HIGH PRESSURE CONTINUES TO BUILD SOUTHWARD 
ACROSS CENTRAL AMERICA. THE WINDS ARE GREATEST DURING THE 
OVERNIGHT AND EARLY MORNING HOURS WITH THE AID OF THE DRAINAGE 
FLOW. THE STRONGEST WINDS OF UP TO 30 KT ARE BLOWING ACROSS AND 
DOWNSTREAM OF THE GULF OF PAPAGAYO. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

$$
GR