000
AXPZ20 KNHC 212202
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC THU FEB 21 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 IS CENTERED ALONG 5N77W 9N86W 6N92W 10N109W 6N115W 
3N130W 3N140W. SCATTERED SHOWERS FROM 1N-8N BETWEEN 81W-90W. 
SCATTERED MODERATE CONVECTION WITHIN 90 NM OF AXIS BETWEEN 
114W-132W.

...DISCUSSION...

SUBTROPICS...
LARGE-SCALE SPLIT FLOW CONTINUES OVER THE WESTERN U.S. AND 
ADJACENT PACIFIC WATERS BUT HAS SHIFTED ABOUT 500 NM FARTHER E 
SINCE YESTERDAY. A LARGE BLOCKING RIDGE IS LOCATED ACROSS THE 
GREAT BASIN AND NORTHERN ROCKIES WHILE AN UPPER TROUGH EXTENDS 
FROM A CUT-OFF LOW OVER COLORADO TO NORTHERN MEXICO THEN SW TO 
18N120W. THE SUBTROPICAL JET IS QUITE STRONG AT THE 
MOMENT...WITH A 160 KT WIND MAXIMUM LYING W OF CALIFORNIA ALONG 
38N THEN DECELERATING A BIT FARTHER E AS THE FLOW DIPS S OVER 
NORTHERN MEXICO. A WEAK COLD FRONT HAS MOVED INTO THE REGION 
FROM 30N130W TO 27N140W BUT WILL QUICKLY DISSIPATE AND LIFT BACK 
AS A WARM FRONT ON FRI. A SECOND COLD FRONT WILL MOVE E OF 140W 
EARLY FRI NIGHT ATTACHED TO A DEVELOPING STORM N OF THE AREA 
THAT IS EXPECTED TO MOVE TOWARDS CALIFORNIA. GALE FORCE WINDS ON 
THE SOUTHERN PERIPHERY OF THE LOW ARE EXPECTED TO BRUSH THE 
DISCUSSION AREA AND THUS A GALE WARNING HAS BEEN ISSUED N OF 28N 
WITHIN 240 NM E OF THE FRONT BEGINNING FRI NIGHT. ELSEWHERE...A 
SURFACE RIDGE IS IN PLACE W OF BAJA CALIFORNIA WITH A 1022 MB 
HIGH ANCHORING IT NEAR 24N122W.

TROPICS...
A CUT-OFF MID/UPPER LOW IS STILL LOCATED OVER THE TROPICAL 
PACIFIC WATERS NEAR 10N138W AND IS ONLY EXPECTED TO DRIFT SLOWLY 
E OVER THE NEXT 48 HOURS. FARTHER E...UPPER LEVEL SPLIT FLOW 
BEGINS NEAR 120W AND THE ASSOCIATED UPPER DIFFLUENCE IS 
ENHANCING DEEP CONVECTION ALONG THE ITCZ BETWEEN 113W-125W. 
STRONG MID-LEVEL RIDGING IS CENTERED OVER THE NW CARIBBEAN AND 
THE MID-LEVEL RIDGE AXIS EXTENDS FARTHER W TO 12N107W.

$$
BERG