000
AXPZ20 KNHC 160933
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC TUE JAN 16 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0845 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 3N77W 5N87W 5N119W 7N131W 6N140W. 
SCATTERED MODERATE CONVECTION WITHIN 60 NM OF AXIS BETWEEN 119W 
AND 122W...AND BETWEEN 130W AND 132W.

...DISCUSSION...
W OF 100W...HIGHLY AMPLIFIED PATTERN CONTINUES OVER THE EPAC 
FORECAST AREA THIS MORNING. WATER VAPOR IMAGERY SHOWS WELL 
DEFINED POSITIVELY TILTED UPPER TROUGH EXTENDING FROM SOUTHERN 
CALIFORNIA TO NEAR 26N124W. S OF THE AXIS...STRONG 120 TO 130 KT 
SWLY FLOW IS EVIDENT...ADVECTING MID AND UPPER CLOUD DECKS 
ACROSS SOUTHERN BAJA AND NW MEXICO. THE TROUGH WILL BE 
REINFORCED THROUGH TODAY BY A SHORT WAVE TROUGH PUSHING INTO THE 
W COAST AND INTO SRN CALIFORNIA TONIGHT. IN THE LOWER 
LEVELS...1033 MB SURFACE PRES TO THE N OF THE AREA IS 
MAINTAINING STRONG NE TO E TRADE WINDS OVER MUCH OF THE AREA W 
OF 110W N OF THE ITCZ. THE TIGHT GRADIENT BETWEEN THE HIGH PRES 
TO THE N AND TROUGHING OVER NRN MEXICO IS ALLOWING STRONG NWLY 
FLOW DOWN THE GULF OF CALIFORNIA TO AS FAR S AS CABO CORRIENTES.

E OF 100W...A COLD AIRMASS ASSOCIATED WITH A 1037 MB SURFACE 
PRES BUILDING OVER TEXAS IS PUSHING A COLD FRONT INTO THE 
WESTERN GULF AND INTO THE BAY OF CAMPECHE. THE COLD DENSE AIR 
AND STRONG HIGH PRES WILL ALLOW FOR GALE CONDITIONS TO SET UP IN 
GULF OF TEHUANTEPEC STARTING TODAY. WINDS AT IXTEPEC ON THE 
PACIFIC SIDE WERE STILL CLOSE TO 20 KT BY LATE EVENING...HINTING 
STRONG MIXING WILL SET UP THIS MORNING. STORM CONDITIONS ARE 
POSSIBLE BY THIS EVENING OVER THE GULF OF TEHUANTEPEC AS BULK OF 
THE COLD DENSE AIR FUNNELS THROUGH THE GAP. RESIDUAL GALES WILL 
PERSIST INTO THU...THEN START TO DIMINISH AS HIGH PRES OVER THE 
GULF OF MEXICO WEAKEN AND SHIFTS E. FURTHER S...SURFACE 
OBSERVATIONS IN NW COSTA RICA SHOW NEAR 20 KT SUSTAINED WINDS AS 
OF THIS EVENING...HINTING THAT GAP FLOW WINDS CONTINUE IN GULF 
OF PAPAGAYO AREA DUE TO STRONG TRADES OVER THE CARIBBEAN. SHIP 
OBSERVATIONS CONFIRM MODEL DEPICTIONS OF FRESH TO STRONG ELY 
WINDS EXTENDING W FAR INTO PACIFIC WATERS TO NEAR 110W. 
MEANWHILE ALOFT...AN UPPER LOW IS DRIFTING ACROSS CENTRAL 
AMERICA INTO THE EPAC...DELIVERING VERY DRY MID AND UPPER LAYER 
AIR...AND KEEPING THE REGION MOSTLY CLOUD FREE.


$$
CHRISTENSEN