000
AXPZ20 KNHC 212201
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN FEB 21 2010

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 
1545 UTC.

...ITCZ...

AXIS IS CENTERED ALONG 4N78W TO 5N91W TO 6N107W 7N117W 6N130W 
6N140W. SCATTERED STRONG CONVECTION IS WITHIN 60 NM N OF THE 
AXIS BETWEEN 111W-113W. SCATTERED MODERATE TO STRONG CONVECTION
IS WITHIN 60 NM N OF THE AXIS BETWEEN 87W-94W. SCATTERED 
MODERATE CONVECTION IS WITHIN 60 NM N OF THE AXIS BETWEEN 
127W-129W.

...DISCUSSION...

A SHEARED UPPER-LEVEL TROUGH EXTENDS FROM THE WESTERN U.S. SW
TO 26N130W TO W OF THE AREA AT 22N140W. A SUBTROPICAL JET STREAM 
ROUNDS THE BASE OF THIS TROUGH AND CONTINUES EWD ALONG 25N TO 
THE COAST OF BAJA CALIFORNIA WITH CORE JET SPEEDS OF 125-150 KT. 
IN ADDITION TO MAINTAINING MAINLY A ZONAL FLOW PATTERN ACROSS 
MOST OF THE AREA...THIS JET ALSO CONTINUES TO ADVECT PLENTIFUL 
MID TO UPPER LEVEL MOISTURE FROM THE DEEP CENTRAL TROPICAL 
PACIFIC NE TO E ACROSS CENTRAL AND SOUTHERN MEXICO AND INTO THE 
BAY OF CAMPECHE AND NW CARIBBEAN SEA. THE UPPER TROUGH WILL 
CONTINUE TO SHEAR OUT AS IS MOVES EWD DURING THE NEXT 24 TO 48 
HOURS. AT THE SURFACE...A 1025 MB HIGH IS ANALYZED NEAR 26N132W
WITH A RIDGE ESE TO NEAR 21N110W. THE HIGH IS FORECAST TO SLOWLY
MOVE E OVER THE NEXT 48 HRS MAINTAINING CONTROL OF THE WIND
REGIME ACROSS THE MAJORITY. THE PRES DIFFERENCE BETWEEN THE HIGH 
AND LOWER PRES ASSOCIATED WITH THE ITCZ CONTINUES TO ALLOW FOR
AN AREA OF NE TO E 20 TO 25 KT TRADE WINDS FROM 8N TO 18N W OF 
120W. AN ASCAT PASS FROM NEAR 18 UTC THIS AFTERNOON DEPICTED
THIS AREA OF WINDS. WITH THE HIGH FORECAST TO SHIFT EASTWARD 
OVER THE NEXT 48 HRS...EXPECT THE TRADES TO EXPAND SOME EASTWARD
TO NEAR 112W IN 48 HOURS. ALSO...WITH THE EASTWARD MOTION OF
THE HIGH EXPECT NW TO N WINDS TO INCREASE ALONG AND ACROSS THE 
BAJA CALIFORNIA PENINSULA IN ABOUT 24 HOURS AND ACROSS THE GULF 
OF CALIFORNIA IN APPROXIMATELY 30 HOURS AS PRES GRADIENT 
TIGHTENS BETWEEN THE HIGH AND LOWER PRES OVER NORTHERN MEXICO. 
THE GRADIENT WILL TIGHTEN WITHIN 90 NM OF THE MEXICAN COAST FROM
16N TO 22N IN 12 HRS...INCREASING FROM 17N TO 25N WITHIN 150 NM 
OF THE MEXICAN IN 48 HRS WHERE NW WINDS OF 20-25 KT CAN BE 
EXPECTED.

ELSEWHERE A NEARLY STATIONARY ELONGATED UPPER LEVEL ANTICYCLONE 
IS NOTED ALONG 08N BETWEEN 95W AND 127W WITH THE ACTUAL CENTER
NEAR 102W. ASSOCIATED BROAD MID TO UPPER LEVEL ANTICYCLONIC FLOW 
COVERS THE AREA SOUTH OF THE ABOVE MENTIONED JET STREAM AND W OF 
ABOUT 94W. A MID TO UPPER LEVEL TROUGH EXTENDS FROM NEAR THE 
GULF OF TEHUANTEPEC TO NEAR 8N96W. A DIFFLUENT PATTERN ALOFT 
BETWEEN THESE TWO UPPER LEVEL FEATURES IS HELPING TO INDUCE 
SCATTERED MODERATE CONVECTION WITHIN 60 NM EITHER SIDE OF A 
SURFACE TROUGH EMBEDDED IN THE ITCZ THAT EXTENDS ALONG 107W FROM 
4N TO 10N. THE TROUGH IS WEAKENING WITH TIME AS IT MOVES W ABOUT
5-10 KT.

GAP WINDS...

AN ASCAT PASS FROM JUTS PAST 1600 UTC THIS MORNING MISSED 
THE GULF OF PAPAGAYO...BUT SHOWED NE WINDS OF 15-20 KT DOWNWIND
FROM GULF FROM 9N TO 12N BETWEEN 88W AND 90W. AS THE GRADIENT 
WEAKENS OVER THE SE CARIBBEAN SEA...THESE WINDS WILL DIMINISH TO
LESS THAN 20 KT IN ABOUT 12 HRS.

LOOKING AHEAD...NWP MODELS ARE CONSISTENTLY FORECASTING THE NEXT 
GULF OF TEHUANTEPEC EVENT TO BEGIN BY LATE WED...WITH WINDS 
LIKELY REACHING GALE FORCE THU.

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

$$
AGUIRRE