000
AXPZ20 KNHC 090947
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE FEB 09 2010

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0915 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED ALONG 06N77W 
TO 08N88W TO 04N106W TO 09N131W TO 06N140W. SCATTERED MODERATE 
AND ISOLATED STRONG CONVECTION WAS NOTED WITHIN 180 NM N OF THE 
AXIS BETWEEN 120W AND 123W.

...DISCUSSION...

AN UPPER LEVEL LOW IS CENTERED WELL N OF THE DISCUSSION AREA 
NEAR 38N125W WITH A DIGGING UPPER LEVEL TROUGH EXTENDING FROM 
THE LOW TO 32N125W TO 15N137W. RIDGING IS E OF THIS FEATURE 
EXTENDING FROM THE BAJA PENINSULA TO 12N106W AND ASSOCIATED 
UPPER LEVEL DIVERGENCE WILL MAINTAIN ACTIVE CONVECTION ALONG AND 
N OF THE ITCZ. NUMEROUS MODERATE CONVECTION WAS NOTED FROM 15N 
TO 27N BETWEEN 121W AND 134W. A VERY TIGHT PRES GRADIENT IS IN 
PLACE IN THIS SAME AREA BETWEEN 1027 MB SURFACE HIGH PRES 
CENTERED NEAR 37N137W AND A PRONOUNCED SURFACE TROUGH EXTENDING 
FROM 14N116W TO 07N125W. NE-E TRADES OF 20-30 KT ARE OCCURRING 
FROM 07N TO 23N W OF 120W AS INDICATED BY A 0602 UTC ASCAT 
SCATTEROMETER PASS. ASCAT ALSO CAPTURED E TO SE WINDS OF 20 TO 
30 KT WITHIN 180 NM SE OF THE TROUGH AXIS. THIS TROUGH WILL 
LINGER IN THE CENTRAL EPAC DURING THE NEXT 48 HOURS EXTENDING 
FROM 14N113W TO 05N126W IN 24 HOURS AND THEN FROM 19N109W TO 
10N120W IN 48 HOURS. THE AFOREMENTIONED HIGH WILL SHIFT SE-S TO 
NEAR 30N135W IN 24 HOURS FURTHER TIGHTENING THE PRES GRADIENT. 
AS A RESULT THE AREA OF NE-E 20-25 KT TRADES WILL FURTHER EXPAND 
TO THE E. 

IN ADDITION...NW WINDS OF 20-25 KT ON THE E SIDE OF THE HIGH 
WILL MOVE INTO THE WATERS NW OF THE BAJA PENINSULA DUE TO A 
TIGHT PRES GRADIENT BETWEEN THE HIGH AND LOW PRES TROUGHING OVER 
INTERIOR U.S. CALIFORNIA. 

MEANWHILE A LARGE UPPER LEVEL ANTICYCLONE IS CENTERED NEAR 
13N167W WITH AN ELONGATED UPPER RIDGE AXIS EXTENDING FROM THE 
ANTICYCLONE NW OF THE DISCUSSION AREA NEAR 44N140W TO THE W OF 
THE AFOREMENTIONED UPPER TROUGH.

OVER THE EASTERN PORTION OF THE DISCUSSION AREA NEARLY ZONAL 
FLOW IS IN PLACE FROM THE EQUATOR TO 16N E OF 108W. WATER VAPOR 
SATELLITE IMAGERY INDICATES VERY DRY AND STABLE AIR IN PLACE IN 
THIS AREA WITH SUBSIDENCE HELPING TO SUPPRESS ANY CONVECTION 
ALONG THE ITCZ.

GAP WINDS...
A STRONG COLD FRONT IN THE NW GULF OF MEXICO WILL PUSH SE 
THROUGH THE BAY OF CAMPECHE AND INTO THE NW CARIBBEAN SEA 
TONIGHT. STRONG NORTHERLY WINDS WILL BE FUNNELED THROUGH THE 
CHIVELAS PASS ACROSS THE ISTHMUS OF TEHUANTEPEC AND WILL 
INCREASE TO GALE FORCE IN THE GULF OF TEHUANTEPEC BY EARLY WED. 
ACCORDINGLY A GALE WARNING HAS BEEN ISSUED FROM 12 UTC WED 
THROUGH 06 UTC THU. 

A 0238 UTC ASCAT SCATTEROMETER PASS CONFIRMED THAT WINDS ARE 
CURRENTLY LESS THAN 20 KT IN THE GULF OF PAPAGAYO ALTHOUGH WINDS 
WILL INCREASE TO 20-25 KT THERE IN 36 HOURS AS WINDS IN THE SW 
CARIBBEAN SEA BECOME EASTERLY.

THE PRES GRADIENT IN THE SW CARIBBEAN SEA WILL STRENGTHEN IN 24 
HOURS ENHANCING NORTHERLY FLOW INTO THE GULF OF PANAMA WITH 
WINDS INCREASING TO 20 KT BY LATE TONIGHT THROUGH WED NIGHT.

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

$$
LEWITSKY