000
AXPZ20 KNHC 301515
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE JAN 30 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 
1500 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 3N78W 6N87W 4N110W 6N140W. SCATTERED 
MODERATE/ISOLATED STRONG CONVECTION FROM 2N-5N E OF 80W...AND 
WITHIN 60 NM OF AXIS BETWEEN 88W-102W.
    
...DISCUSSION...

SLIGHT REX BLOCK STILL IN PLACE OFF THE WRN U.S. COAST BUT THE 
UPPER HIGH OFF THE ALASKAN PANHANDLE AND THE UPPER LOW W OF LOS 
ANGELES ARE BECOMING INCREASINGLY OFFSET FROM EACH OTHER. NLY 
FLOW ON THE E SIDE OF THE HIGH WILL FINALLY DRIVE THE UPPER LOW 
SWD THEN EWD ACROSS NRN MEXICO WITH THE MID-LATITUDE FLOW 
THROUGH THU. FAST-MOVING ZONAL FLOW LIES S OF THE UPPER LOW WITH 
THE SUBTROPICAL JET CENTERED ALONG 25N/26N...AND UPPER LEVEL 
MOISTURE/CLOUDINESS IS BEGINNING TO MOVE ACROSS 140W FROM A 
LARGE AND COMPLEX SYSTEM N OF HAWAII. AT THE SURFACE...THE 
LOW-LEVEL RIDGE HAS BEEN TRUNCATED BY THE UPPER FLOW WITH A WEAK 
SURFACE TROUGH FROM NRN BAJA TO 27N125W THEN CONNECTING TO A 
WARM FRONT TO 30N136W. A FEW SHOWERS MAY BRUSH THROUGH THE FAR 
NW PART OF THE AREA WITHIN 24 HRS AS THE SYSTEM TO THE W 
APPROACHES THE REGION.

WITH THE UPPER FLOW HAVING BECOME MORE ZONAL WITHIN THE PAST 24 
HRS...THERE IS VERY LITTLE UPPER DIFFLUENCE AND HENCE VIRTUALLY 
NO MOISTURE PLUME EMANATING OUT OF THE TROPICS AS HAS BEEN 
COMMON FOR THE PAST SEVERAL WEEKS. MODERATE/STRONG SUBSIDENCE 
DOMINATES W OF 110W WITH A MORE OR LESS LINEAR ITCZ.

A MID-LEVEL RIDGE REACHES FROM THE CARIBBEAN WWD ACROSS 
HONDURAS/NICARAGUA TO 12N110W WITH THE BULK OF THE MID-LATITUDE 
FLOW RUNNING ACROSS MEXICO INTO THE GULF OF MEXICO. THERE IS A 
WEAK UPPER TROUGH ALONG 106W WHICH MAY BE HELPING TO PRODUCE 
INCREASED CLOUDINESS/SOME CONVECTIVE ACTIVITY ALONG THE ITCZ 
BETWEEN 90W-104W. SOME TSTMS ARE ALSO OCCURRING JUST OFFSHORE 
THE COLOMBIAN COAST S OF 5N LIKELY DUE TO LOW-LEVEL CONVERGENCE 
AT THE SRN EXTENT OF THE GULF OF PANAMA WINDS.

WINDS HAVE DECREASED OVER THE GULF OF TEHUANTEPEC TO 20-25 
KT...AND SHOULD HOVER NEAR 20 KT FOR ANOTHER 36 HRS OR SO. GULF 
OF PAPAGAYO WINDS WILL REMAIN AT 20-25 KT FOR THE NEAR 
FUTURE...AND GULF OF PANAMA WINDS WILL BE STEADY AT 20 KT FOR 
SEVERAL DAYS.

$$
BERG