000
AXPZ20 KNHC 102155
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC SAT FEB 10 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2145 UTC.

...ITCZ...
ITCZ AXIS CENTERED ALONG 1N79W 4N87W 2N106W 4N121W 3N140W. 
SCATTERED MODERATE CONVECTION WITHIN 30 NM OF AXIS BETWEEN 97W 
AND 108W. ISOLATED MODERATE ALONG ITCZ AXIS BETWEEN 111W AND 
129W.

...DISCUSSION...

UPPER DIFFLUENCE NOTED BETWEEN THE UPPER TROUGH OFF THE U.S. 
WEST COAST AND RIDGING EXTENDING N FROM BAJA THROUGH WASHINGTON 
STATE. THIS IS SUPPORTING THE BAND OF UPPER MOISTURE SEEN IN WV 
IMAGERY UPSTREAM FROM BAJA...N OF 24N AND E OF 130W. THE UPPER 
TROUGH HAS AN ASSOCIATED COLD FRONT THAT ENTERS THE AREA AT 
32N126W AND CONTINUES SW TO 21N140W. A THIN ROPE CLOUD NOTED 
WITH THIS FRONT...WITH SHOWERS ANTICIPATED WITHIN 90NM EITHER 
SIDE. FRESH TO STRONG PREFRONTAL AND POSTFRONTAL WINDS STILL 
EXIST MAINLY N OF 27N...BUT EXPECTED TO RELAX THROUGH TOMORROW 
AS THE ENERGY LIFTS N. HOWEVER...LARGE...LONG PERIOD NW SWELL 
WILL CONTINUE TO SPREAD THROUGH THE AREA. SEE HIGH SEAS FORECAST 
UNDER HEADER MIAHSFEP2 FOR MORE DETAILS. UKMET WAVE MODEL SEEMS 
TO BE THE MOST ON TRACK WITH THIS SWELL EVENT WITH BOTH THE NWW3 
AND FNMOC WAVE MODELS SLIGHTLY OVERDONE...IN COMPARISON WITH THE 
1450Z JASON ALTIMETER PASS. 

MUCH OF THE AREA S OF 20N W OF 110W...OUTSIDE OF THE ITCZ...IS 
DOMINATED BY DRY MID TO UPPER AIR AND RIDGING. THERE IS AN UPPER 
TROUGH EXTENDING S THROUGH CENTRAL MEXICO ALONG 18N103W TO 
9N109W. UPPER CONFLUENCE BETWEEN THE SW FLOW AHEAD OF THIS 
TROUGH WITH THE SLY FLOW AROUND CARIBBEAN RIDGING IS SUPPORTING 
THE EXTREMELY DRY/STABLE AIR IN THE FAR NE PACIFIC...ESPECIALLY 
N OF 6N BETWEEN 100W-82W...WITH THE DRIEST UPPER AIR NOTED NEAR 
NICARAGUA. 

ELSEWHERE AT THE SFC...A PERSISTENT 1022 MB HIGH IS W OF CENTRAL 
BAJA NEAR 27N121W. MODERATE TRADES ARE S OF THIS HIGH...MAINLY 
FROM 3N-14N W OF 110W. GAP WINDS...NLY WINDS IN THE GULF OF 
TEHUANTEPEC 20-25 KT ARE EXPECTED TO FURTHER INCREASE TO 
20-30 KT SUN...THEN RELAX INTO MON. NE TO E WINDS 20-30 KT IN 
THE GULF OF PAPAGAYO CONTINUE INTO SUN THEN RELAX TO ABOUT 20 KT 
MON. NLY WINDS TO 20 KT IN THE GULF OF PANAMA EXPECTED TO 
DIMINISH TO LESS THAN 20 KT BY MON.

$$
WILLIS