000
AXPZ20 KNHC 231540
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE FEB 23 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 
1500 UTC.

...ITCZ...

THE AXIS IS CENTERED ALONG 07N78W TO 03N89W TO 08N110W TO 
03N126W TO 01N140W. NUMEROUS MODERATE TO STRONG CONVECTION IS 
WITHIN 300 NM S OF THE AXIS E OF 81W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 180 NM N OF THE AXIS BETWEEN 81W AND 
87W AND WITHIN 180 NM S OF THE AXIS BETWEEN 85W AND 92W. 
SCATTERED MODERATE AND ISOLATED STRONG CONVECTION IS WITHIN 210 
NM S OF THE AXIS BETWEEN 105W AND 112W. SCATTERED MODERATE TO 
STRONG CONVECTION IS WITHIN 150 NM N OF THE AXIS BETWEEN 112W 
AND 122W.

...DISCUSSION...

AN UPPER LEVEL TROUGH EXTENDS FROM AN UPPER LEVEL LOW CENTERED 
OVER SW NEW MEXICO TO 29N112W TO 24N120W. AN UPPER LEVEL RIDGE 
IS PRESENT W OF THE TROUGH EXTENDING FROM THE U.S. WEST COAST 
STATES TO 32N124W TO 29N126W. A SHEARED UPPER TROUGH IS 
WEAKENING AS IT ENCOUNTERS THIS RIDGE WITH THE TROUGH AXIS 
EXTENDING FROM 32N130W TO 27N136W. MAINLY ZONAL FLOW WITH DRY 
AND STABLE AIR EXISTS S OF THESE FEATURES FROM 17N TO 23N. A 
VERY PERSISTENT SUBTROPICAL JET ENTERS THE REGION NEAR 12N140W 
TO 15N123W ACROSS CENTRAL MEXICO AND INTO THE GULF OF MEXICO. 
SATELLITE DERIVED WINDS INDICATE JET CORE WINDS OF 70 TO 110 KT. 
THIS JET CONTINUES TO ADVECT PLENTIFUL MID TO UPPER LEVEL 
MOISTURE IN THE FORM OF SCATTERED TO BROKEN HIGH CLOUDS FROM THE 
DEEP CENTRAL TROPICAL PACIFIC NE TO E ACROSS SOUTHERN MEXICO AND 
OVER THE SW GULF OF MEXICO. ELSEWHERE ALOFT A NEARLY STATIONARY 
ANTICYCLONE IS NOTED ALONG 08N E OF 122W. ASSOCIATED BROAD MID 
TO UPPER LEVEL ANTICYCLONIC FLOW COVERS THE MAJORITY OF THE 
DISCUSSION AREA S OF THE ABOVE MENTIONED JET STREAM AND E OF 
125W. ITCZ CONVECTION REMAINS PRONOUNCED WITH SCATTERED MODERATE 
TO STRONG CONVECTION BETWEEN 81W AND 122W WHICH IS RATHER ACTIVE 
FOR THIS TIME OF YEAR AS THE UPPER RIDGE CONTINUES TO PROVIDE A 
FAVORABLE DIFFLUENT ENVIRONMENT ALOFT.

AT THE SURFACE...1024 MB HIGH PRES IS CENTERED NEAR 27N129W WITH 
A SURFACE RIDGE AXIS EXTENDING FROM THERE TO NEAR 15N110W. THIS 
HIGH IS CONTROLLING THE WIND REGIME ACROSS THE MAJORITY OF THE 
AREA W OF 100W. THE PRES DIFFERENCE BETWEEN THIS HIGH AND LOWER 
PRES ASSOCIATED WITH THE ITCZ CONTINUES TO GENERATE A LARGE AREA 
OF NE TO E TRADE WINDS OF 20 TO 25 KT FROM 06N TO 19N W OF 115W 
AS CAPTURED BY EARLIER ASCAT SCATTEROMETER PASSES. THE HIGH WILL 
GRADUALLY SHIFT TO THE E WHILE THE AREA OF TRADES AROUND THE E 
AND S PERIPHERY OF THE RIDGE CHANGE VERY LITTLE DURING THE NEXT 
48 HOURS. MEANWHILE A SURFACE TROUGH IS PRESENT OVER MEXICO 
ALONG THE E COAST OF THE GULF OF CALIFORNIA AND A TIGHT PRES 
GRADIENT EXISTS BETWEEN THIS TROUGH AND THE AFOREMENTIONED RIDGE 
W OF THE BAJA PENINSULA. NW TO N WINDS OF 20 TO 25 KT CONTINUE 
TO GET FUNNELED UP ALONG THE W COAST OF THE BAJA WHILE NW TO N 
WINDS OF 20 TO 30 KT ARE NOW PRESENT IN THE GULF OF CALIFORNIA. 
THERE IS STILL A CHANCE THAT MINIMAL GALE FORCE CONDITIONS WILL 
DEVELOP IN THE CENTRAL GULF OF CALIFORNIA TONIGHT ALTHOUGH 
LATEST MODEL GUIDANCE KEEPS WINDS JUST BELOW GALE FORCE. THESE 
NORTHERLY WINDS ARE ALSO GETTING DAMNED UP AGAINST THE COAST OF 
MEXICO FROM 17N TO 23N BETWEEN 103W AND 110W. 

LONG PERIOD NW SWELL CONTINUES TO PROPAGATE ACROSS THE MAJORITY 
OF THE DISCUSSION AREA MAINLY W OF 100W WITH SIGNIFICANT WAVE 
HEIGHTS PEAKING AT 13 FT OVER THE FAR NW CORNER OF THE AREA. 
ANOTHER ROUND/SET OF NW SWELL IS FORECAST TO PROPAGATE INTO THE 
FAR NW PORTION LATE TUE WITH SIGNIFICANT WAVE HEIGHTS BUILDING 
TO UP TO 17 FT OVER THE FAR NW CORNER. MEANWHILE SW SWELL WILL 
MOVE N OF THE EQUATOR DURING THE NEXT 48 HOURS COMMINGLING WITH 
NW SWELL...MAINLY S OF 08N.

GAP WINDS...
A STRONG COLD FRONT WILL PUSH S THROUGH THE GULF OF MEXICO AND 
BAY OF CAMPECHE ON WED WHICH WILL FUNNEL NORTHERLY WINDS THROUGH 
THE CHIVELAS PASS AND ACROSS THE ISTHMUS OF TEHUANTEPEC AND 
INTO THE GULF OF TEHUANTEPEC. WINDS WILL INCREASE TO 20 KT IN 24 
HOURS THEN WILL QUICKLY INCREASE TO GALE FORCE WITHIN 30 HOURS. 
GFS 925 MB WINDS REACH STORM FORCE ALTHOUGH THERE IS STILL SOME 
DOUBT AS TO WHETHER OR NOT THE STRONGER WINDS WILL MIX DOWN/ 
REACH THE SURFACE SO WILL REFRAIN FROM UPGRADING TO A STORM 
WARNING AT THIS TIME. IN ANY EVENT GALE FORCE WINDS LOOK TO 
PERSIST THROUGH AT LEAST 48 HOURS ONCE THEY BEGIN AROUND 18 UTC 
WED.

THE COLD FRONT MENTIONED ABOVE WILL PUSH SE THROUGH THE NW 
CARIBBEAN WED NIGHT AND N TO NE WINDS OF 20 TO 25 KT WILL BEGIN 
IN 48 HOURS IN THE GULF OF FONSECA AS THEY GET CHANNELED 
THROUGH THE PASSES OF CENTRAL AMERICA.

JUST BEYOND 48 HOURS...THE FRONT WILL CONTINUE TO PUSH SE AND 
INTO THE SW CARIBBEAN WITH NE TO E WINDS INCREASING TO 20 KT IN 
THE GULF OF PAPAGAYO BEHIND THE FRONT.

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

$$
LEWITSKY