000
AXPZ20 KNHC 040312
TWDEP 

TROPICAL WEATHER DISCUSSION    
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC THU FEB 04 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 
0130 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED ALONG 03N77W 
TO  05N94W TO 09N107W TO 06N120W TO 04N140W. NO SIGNIFICANT DEEP 
CONVECTION IS FOUND ALONG THE ITCZ AT THIS TIME.     

...DISCUSSION...

A DEEP LAYER LOW NEAR THE BORDER OF MEXICO AND NEW MEXICO WITH A 
TROUGH EXTENDING S OVER WESTERN MEXICO AND INTO THE TROPICAL 
PACIFIC DOMINATES THE WEATHER PATTERN OVER MUCH OF THE REGION W 
OF 120W. ALOFT...A 130-150 KT SUBTROPICAL UPPER JET BRANCH LIES 
OVER N WATERS ON THE W SIDE OF THE TROUGH...WITH CORE WINDS OF 
80-100 KT ROUNDING THE BASE OF THE TROUGH AND TURNING NE AND 
INCREASING TO A 120-140 KT SOUTHERLY JET INTO THE U.S. SOUTHERN 
PLAINS. UPPER LEVEL DIFFLUENCE BETWEEN THIS TROUGH AND AN UPPER 
RIDGE AXIS OVER THE CENTRAL GULF OF MEXICO IS SUPPORTING 
WIDESPREAD CLOUDINESS AND PRECIPITATION PRIMARILY E OF THE 
TROUGH AXIS OVER MAINLAND MEXICO. LOW LEVEL MOISTURE CONVERGED 
ON THE EASTERN EDGE OF A SURFACE TROUGH FROM 17N102W TO 09N110W 
IS FUELING SCATTERED MODERATE CONVECTION WITHIN 300 NM SE OF 
THIS TROUGH AXIS. 20 KT WINDS CAN BE FOUND NEAR THE TROUGH WHICH 
IS EXPECTED TO SHIFT EASTWARD WITH THE DEEP LAYER TROUGH 
TOMORROW AND DISSIPATE FRI. PRECIPITABLE WATER VALUES ARE 
CURRENTLY AROUND 2.25 INCHES NEAR THIS SURFACE TROUGH. 50-70 KT 
MID-LEVEL SW WINDS ARE PUMPING MOSITURE NORTHEASTWARD INTO 
MEXICO...WITH A BAND OF MID TO HIGH CLOUDS FOUND ELSEWHERE 
WITHIN 300 NM OF A LINE FROM THE ITCZ NEAR 110W TO MEXICO CITY. 
MODERATE TO STRONG SUBSIDENCE DOMINATES THE REGION JUST EAST OF 
HERE AND INTO CENTRAL AMERICA.

1014 MB WEAK HIGH PRES NEAR 25N126W WILL BE PUSHED EWD ACROSS 
THE N WATERS TONIGHT AND TOMORROW BY A STRONG COLD FRONT 
ENTERING NW WATERS. 20 KT NE TRADE WINDS CURRENTLY LIE S OF THIS 
HIGH FROM 06N TO 14N BETWEEN 123W AND 137W ACCORDING TO THE 
ASCAT PASSES FROM 1720 AND 1900 UTC AND SHIP A8MW6 WHO REPORTED 
20 KT NE WINDS NEAR 10N132W AT 0000 UTC. EXPECT TRADES TO 
DIMINISH BELOW 20 KT TOMORROW. THE AFOREMENTIONED COLD FRONT 
WILL MOVE INTO THE FAR NW PORTION OF THE DISCUSSION AREA 
TONIGHT. A GALE WARNING IS ALREADY IN EFFECT N OF 26N W OF 137W 
FOR THE S-SW WINDS IN ADVANCE OF THE FRONT. THE LAST AVAILABLE 
DATA HERE WAS THE 1854 UTC ASCAT PASS WHICH SHOWED WINDS JUST 
BELOW GALE FORCE EARLIER TODAY AT 30N140W. THESE WINDS HAVE 
SURELY SHIFTED E IN THE LAST 5 HOURS AND ASCAT HAS A LOW BIAS 
WITH WINDS THIS STRONG. THE GALE WARNING CONTINUES UNTIL THU 
AFTERNOON...WITH GALE FORCE WINDS EXPECTED TO BE FELT OVER FAR N 
WATERS AS FAR E AS 128W BEFORE WINDS DIMINISH. A SECONDARY COLD 
FRONT NORTH OF THE AREA WILL BEGIN TO APPROACH THIS FRONT FRI AS 
IT DISSIPATES TO A FRONTAL TROUGH. THIS SYSTEM WILL BRING A NEW 
SURGE OF NW SWELL INTO THE REGION...WITH SEAS EXPECTED TO REACH 
21 FT IN FAR NW WATERS FRI AFTERNOON. 

GAP WINDS...
THE 1536 UTC ASCAT PASS SHOWS WINDS HAVE DROPPED BELOW 20 KT IN 
THE GULF OF TEHUANTEPEC. THE SAME PASS SHOWS STRONG NE TO E 
WINDS CONTINUE IN THE GULF OF PAPAGAYO...WITH WINDS EXPECTED TO 
BE STRONGEST DURING THE OVERNIGHT AND EARLY MORNING HOURS WITH 
THE AID OF DRAINAGE FLOW. WINDS HERE ARE EXPECTED TO DIMINISH TO 
20 KT BY FRI AFTERNOON. SIMILARLY...THE 20 KT WINDS CURRENTLY IN 
THE GULF OF PANAMA ARE EXPECTED TO DIMINISH BY FRI NIGHT WHEN 
THE PRES GRADIENT BETWEEN LOW PRES IN COLOMBIA AND HIGH PRES TO 
THE NORTH WEAKENS AS THE DEEP LAYER SYSTEM OVER MEXICO AT THE 
MOMENT MOVES THROUGH THE GULF OF MEXICO. THE NEXT TEHUANTEPEC 
EVENT WILL LIKELY BEGIN SATURDAY...BUT IT DOES NOT APPEAR THAT 
IT WILL BECOME STRONG ENOUGH TO REQUIRE A WARNING.

ELSEWHERE...FORECAST WATERS ARE DOMINATED BY NW SWELL AND 
GENERALLY LIGHT WINDS. 

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

$$
SCHAUER