000
AXPZ20 KNHC 171628
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JAN 17 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 3N78W 4N90W 3N100W 4N110W 5N120W 
5N130W 5N140W. NO SIGNIFICANT CONVECTION IS NOTED.

...DISCUSSION...

W OF 100W...
UPPER TROUGH AXIS EXTENDS FROM SOUTHERN CALIFORNIA THROUGH 
27N130W TO A MID/UPPER LEVEL CYCLONIC CIRCULATION NEAR 
26N136W...THEN CONTINUES SWD TO 18N136W TO 12N133W. A HIGHLY 
AMPLIFIED RIDGE IS LOCATED JUST NW OF THE REGION WITH NLY FLOW 
AROUND THE RIDGE DROPPING SWD INTO THE REGION BEHIND THE TROUGH. 
STRONG SUBSIDENCE AND ASSOCIATED DRY AIR HAS ENTERED THE REGION 
BEHIND THE TROUGH S OF 23.5N. SATELLITE DERIVED WINDS OF 80-100 
KT ARE WITHIN JET STREAM CORE THAT IS VISIBLE TO THE SE OF THE 
TROUGH WITHIN 150 NM EITHER SIDE OF LINE 18N124W 23N117W NEWD 
ACROSS SRN BAJA CALIFORNIA AND ACROSS NRN MEXICO INTO TEXAS AND 
THE BETTER HALF OF THE SE UNITED STATES. ABUNDANT MID AND UPPER 
LEVEL DEEP TROPICAL MOISTURE WITHIN ABOUT 800 NM SE OF THE JET 
STREAM IS BEING ADVECTED NEWD TOWARDS MUCH OF BAJA 
CALIFORNIA...MEXICO AND THE SRN AND E UNITED STATES.

AT THE SURFACE...A 1034 MB HIGH CENTERED ANALYZED TO THE N OF 
THE REGION NEAR 40.5N134W CONTINUES TO CREATE A VERY TIGHT
PRES GRADIENT RESULTING IN STRONG TRADES GENERALLY N OF 5N...AS 
NOTED BY RECENT SHIP OBSERVATIONS AND IN LAST NIGHT'S QUIKSCAT
PASS. WIDESPREAD STRATA CUMULUS FIELDS ARE NOTED AS WELL ON 
SATELLITE IMAGERY...MAINLY N OF 15N. THIS MORNING'S QUIKSCAT
PASS REVEALED SOME NW 20 KT WINDS NEAR THE MOUTH OF GULF OF 
CALIFORNIA AND OFF CABO CORRIENTES. THIS FLOW WILL GENERALLY
LAST FOR THE NEXT FEW DAYS.

GULF OF TEHUANTEPEC...COLD AIR IS FUNNELING FROM THE GULF OF 
MEXICO THROUGH THE TEHUANTEPEC ISTHMUS. THIS MORNING'S QUIKSCAT
PASS AT 1222 UTC REVEALED SEVERAL 50 KT WIND BARBS ALONG WITH 
ONE 55 KT WIND BARB OVER THE GULF OF TEHUANTEPEC. A STORM 
WARNING IS IN EFFECT FOR THE AREA AND SHOULD LAST TO AROUND 00Z 
TONIGHT. HOWEVER...IT WILL TAKE SOME TIME FOR THE DENSER AIR N 
OF THE ISTHMUS TO MODIFY AND/OR SHIFT NWD. THEREAFTER...EXPECT 
GALE CONDITIONS TO POSSIBLY LAST THROUGH FRI MORNING IN THE RANGE
OF 25-35 KT.

GULF OF PAPAGAYO...STRONG ELY WINDS OVER CARIBBEAN CONTINUE TO 
FUNNEL THROUGH VALLEYS OVER NRN COSTA RICA AND SRN NICARAGUA. 
OBSERVATIONS FROM MRLB...LIBERIA...IN NW COSTA RICA INDICATE 
SUSTAINED 20 TO 22 KT WINDS WITH GUSTS TO 32 KT EARLIER THIS 
MORNING. THIS WOULD SUPPORT 25-30 KT OVER THE GULF OF PAPAGAYO. 
MODELS SUGGEST THIS TREND WILL PERSIST AT LEAST THROUGH FRI.

ELSEWHERE E OF 100W...MID AND UPPER LEVELS REMAIN DRY OVER MOST 
OF CENTRAL AMERICA AND ADJACENT PACIFIC WATERS. UPPER RIDGE 
EXTENDS ACROSS SRN MEXICO AND GUATEMALA. ANOTHER RIDGE IS 
PRESSING NWD JUST E OF CENTRAL AMERICA OVER THE CARIBBEAN SEA SE 
OF THE GUATEMALA/HONDURAS BORDER. A BROAD MID/UPPER CYCLONIC 
CIRCULATION AS SEEN ON WATER VAPOR IMAGERY IS MOVING WWD 15-20 
KT S OF RIDGE AXIS OVER NICARAGUA AND COSTA RICA. THE QUIKSCAT 
PASS FROM 1220 UTC THIS MORNING SHOWED THE STRONG GAP WINDS FROM 
THE TEHUANTEPEC AND PAPAGAYO AREAS ARE CONVERGING AS FAR W AS 
100W GENERALLY N OF 5N. GULF OF PANAMA WINDS HAVE DIMINISH FOR
NOW...BUT ARE EXPECTED TO INCREASE ONCE AGAIN BY THIS EVENING
AS ANOTHER SHOT OF STRONG NELY CARIBBEAN FLOW PUNCHES THROUGH
THE ISTHMUS OF SRN CENTRAL AMERICA.

$$
AGUIRRE