000
AXPZ20 KNHC 232205
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC WED JAN 23 2008

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...
ITCZ AXIS ALONG N79W 4N100W 7N110W 7N125W 10N135W 8N140W. 
SCATTERED MODERATE WITHIN 90NM EITHER SIDE OF AXIS FROM 115W TO 
119W. 

...DISCUSSION...
W OF 110W...BROAD UPPER TROUGH EXTENDS FROM CLOSED UPPER CYCLONE 
OFF THE CENTRAL CALIFORNIA COAST...SW TO 31N140W. AN ASSOCIATED 
1015 MB SURFACE LOW IS CENTERED BENEATH THE UPPER CYCLONE...WITH 
A TROUGH EXTENDING TO 30N122W THEN TO 25N129W. A STATIONARY 1023 
MB SURFACE HIGH IS ANCHORED TO THE E OF THE TROUGH OFF THE 
CENTRAL BAJA COAST NEAR 26N117W. SCATTEROMETER AND SHIP 
OBSERVATIONS SHOW STRONG NLY WINDS ON THE W SIDE OF THE SURFACE 
LOW...AND VISIBLE IMAGERY SHOWS LARGE FIELD OF STRATOCUMULUS 
ADVECTING S IN A BROAD ARC...INDICATIVE OF A COLD FRONT FROM 
30N120W TO 25N130W TO 26N135W. FURTHER S...QUIKSCAT AND VISIBLE 
IMAGERY SHOW A PERSISTENT BUT WEAKENING SURFACE TROUGH ALONG THE 
ITCZ NEAR FROM 13N131W TO 8N137W...WITH FRESH TRADES TO THE N OF 
THE TROUGH. DIVERGENCE ALOFT IS ALSO ENHANCING FORMATION OF A 
SURFACE TROUGH ALONG THE ITCZ NEAR 120W...WITH MODERATE 
CONVECTION AS DESCRIBED ABOVE. FOR THE FORECAST...ANOTHER UPPER 
TROUGH WILL DIG THROUGH THE GULF OF ALASKA AND REINFORCE THE LOW 
OFF CALIFORNIA. THE ATTENDANT SURFACE LOW WILL DEEPEN 
ACCORDINGLY...ALLOWING SURGE OF NLY WINDS BEHIND A REINFORCING 
COLD FRONT AS FAR S AS 20N THROUGH SAT. WINDS MAY REACH NEAR 
GALE IN SOME AREAS N OF 28N W OF 120W BY FRI. IN 
ADDITION...ACCOMPANYING LARGE SWELL WILL PUSH AS FAR S AS THE 
EQUATOR THROUGH MON. 

E OF 110W...MORNING SCATTEROMETER DATA SHOW CONTINUING FRESH TO 
STRONG WINDS THROUGH THE GULFS OF TEHUANTEPEC AND PAPAGAYO. 
WINDS THROUGH THE TEHUANTEPEC AREA WILL DIMINISH TEMPORARILY THU 
AS HIGH PRES N OF THE AREA WEAKENS AND SHIFTS E. HOWEVER...A NEW 
RIDGE BUILDS OVER THE CENTRAL U.S. BY FRI BEHIND A SHORT WAVE 
MOVING THROUGH THE NE U.S. AN ASSOCIATED SURFACE RIDGE WILL 
BUILD INTO THE GULF OF MEXICO...ALLOWING FOR AN INCREASE IN 
TEHUANTEPEC WINDS AGAIN BY FRI. PERSISTENT STRONG ELY FLOW OVER 
THE CARIBBEAN WILL KEEP THE PAPAGAYO WINDS ACTIVE INTO THIS 
WEEKEND. MEANWHILE...MODERATE NLY WINDS IN THE SOUTHERN GULF OF 
CALIFORNIA WILL INCREASE SLIGHTLY AS GRADIENT TIGHTENS BETWEEN 
SURFACE HIGH OFF CENTRAL BAJA AND THE MEXICAN HIGHLANDS TO THE 
E. 

$$
CHRISTENSEN