000
AXPZ20 KNHC 062142
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SUN FEB 06 2011

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

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2130 UTC.

...ITCZ...
THE INTERTROPICAL CONVERGENCE ZONE IS ANALYZED ALONG AN AXIS 
FROM 07N80W TO 05N88W TO 09N115W TO 02N140W. SCATTERED MODERATE 
CONVECTION WITHIN 90 NM OF THE AXIS BETWEEN 110W AND 118W. 

...DISCUSSION...
W OF 110W...A REX BLOCK PATTERN REMAINS IN PLACE ACROSS THE 
UPPER LEVELS WITH AN UPPER RIDGE ANCHORED N OF THE AREA NEAR 
36N130W...N OF AN UPPER LOW COMPLEX GENERALLY CENTERED NEAR 
18N131W. THIS OVERALL PATTERN WILL CONTINUE TO BLOCK THE 
EASTWARD ADVANCE OF FRONTAL FEATURES OVER THE N CENTRAL PACIFIC 
FOR AT LEAST THE NEXT 48 TO 72 HOURS. AT THE SURFACE A 1037 MB 
HIGH PRES AREA ASSOCIATED WITH THE UPPER RIDGE WAS CENTERED NEAR 
40N134W WILL SHIFT NW AND MERGE WITH ANOTHER HIGH PRES OVER THE 
NE PACIFIC. THIS WILL ALLOW FRESH TRADE WIND FLOW FROM 09N TO 
28N W OF 120W TO DIMINISH THROUGH 48 HOURS. NE WINDS BETWEEN THE 
HIGH PRES TO THE NORTH AND TROUGHING OVER CALIFORNIA...ARE 
REACHING SW FROM THE SOUTHERN CALIFORNIA COAST TO THE AREA N OF 
27N W OF 125W. AIDING THE NE FLOW...A WEAK 1016 MB SURFACE 
LOW IS SHIFTING S FROM THE SOUTHERN CALIFORNIA COAST...AND WILL 
OPEN INTO A TROUGH ALONG 125W FROM 22N TO 30N BY MON MORNING 
BEFORE DISSIPATING TUE. FRESH NE SWELL GENERATED BY THIS FLOW 
WILL PROPAGATE SW...MIXING WITH LONG PERIOD NW SWELL N OF 25N W 
OF 130W THROUGH TUE. NE SWELL IN THE AREA OF FRESH TRADES IS 
CURRENTLY ESTIMATED TO AS HIGH AS 12 FT FROM 10N TO 25N W OF 
130W...BUT THIS WILL SUBSIDE AND SHIFT W OF 140W THROUGH TUE. 
MIXING WITH THIS...NW SWELL WITH SEAS TO 8 FT WILL COVER MOST OF 
THE AREA W OF 120W OVER THE NEXT 48 HOURS. MEANWHILE CONVECTION 
REMAINS ACTIVE WITHIN 90 NM N OF THE ITCZ BETWEEN 110W AND 
118W...DUE TO PERSISTENT LOW LEVEL CONVERGENCE ALONG THE 
ITCZ...AND DIVERGENT FLOW ALOFT ON THE E SIDE OF THE UPPER LOW 
COMPLEX. 

E OF 110W...FRESH GAP WIND FLOW THROUGH THE GULF OF PAPAGAYO 
WILL DIMINISH SLIGHTLY IN INTENSITY OVER THE NEXT 48 HOURS...BUT 
CONTINUE TO PULSE TO 20 KT MAINLY DURING OVERNIGHT AND EARLY 
MORNING HOURS. N WINDS THROUGH THE ISTHMUS OF PANAMA WILL 
GRADUALLY WEAKEN OVERNIGHT INTO MON AS FLOW OVER THE SW 
CARIBBEAN VEERS MORE TO THE NE TO E. 

MAIN FORECAST ISSUE BY MON EVENING WILL BE THE ONSET OF GALE 
FORCE WINDS THROUGH THE GULF OF TEHUANTEPEC AS DENSER COLD AND 
DRY AIR PUSHES S OVER THE WESTERN GULF OF MEXICO AND INTO 
THROUGH THE CHIVELA PASS. GALE CONDITIONS ARE EXPECTED TO PEAK 
OVERNIGHT MON NIGHT WITH 40-45 KT WINDS EXPECTED. OTHERWISE THE 
1009 MB SURFACE LOW ANALYZED EARLIER NEAR 08N105W APPEARS TO BE 
DISSIPATING. 

$$
COBB