000
AXPZ20 KNHC 311521
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JAN 31 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 1N79W 5N87W 6N110W 4N130W 4N140W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 120 NM OF 
AXIS BETWEEN 98W-110W.
    
...DISCUSSION...

UPPER LEVEL BLOCKING PATTERN OFF THE W COAST OF THE UNITED 
STATES IS FINALLY BREAKING AS WITH THE CUT-OFF LOW NOW MOVING 
EWD ACROSS SRN CALIFORNIA AND NRN BAJA CALIFORNIA. A WEAK 
SURFACE TROUGH IS ASSOCIATED WITH THIS FEATURE AND EXTENDS FROM 
SW ARIZONA TO 24N120W...AND THERE IS A SLIGHT AIR MASS CHANGE 
BEHIND IT AS DRIER/COOLER AIR SLIDES S. FARTHER W...A COMPLEX 
AND MASSIVE CYCLONIC TROUGH IS CENTERED N OF HAWAII WITH 
SHORTWAVE IMPULSES ROTATING NE AND JUST MISSING THE DISCUSSION 
AREA. A LARGE DIFFLUENT REGION LIES E OF THE TROUGH AND IS 
PRODUCING WIDESPREAD MID/UPPER LEVEL CLOUDINESS N OF 20N W OF 
125W. NEARLY ZONAL FLOW AND A LACK OF DEEP MOISTURE S OF 20N HAS 
KEPT THE ENVIRONMENT MOSTLY FAIR WITH THE EXCEPTION OF A FEW 
TSTMS ALONG THE ITCZ.

A MID-LEVEL HIGH REMAINS PLASTERED OFF THE CENTRAL AMERICAN 
COAST NEAR 10N92W WITH MODERATE/STRONG SUBSIDENCE DOMINATING THE 
REGION. SOME DIFFLUENCE ON THE SW PERIPHERY OF THE HIGH IS 
ENHANCING ITCZ CONVECTION ALTHOUGH OVERALL THE ENVIRONMENT IS 
RELATIVELY DRY. GAP WINDS...WITH THE EXCEPTION OF THE GULF OF 
PAPAGAYO...ARE SLOWLY DIMINISHING AS HIGH PRES WEAKENS OVER THE 
GULF OF MEXICO/CARIBBEAN.

$$
NELSON




000
AXPZ20 KNHC 311521
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED JAN 31 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 1N79W 5N87W 6N110W 4N130W 4N140W. 
SCATTERED MODERATE/ISOLATED STRONG CONVECTION WITHIN 120 NM OF 
AXIS BETWEEN 98W-110W.
    
...DISCUSSION...

UPPER LEVEL BLOCKING PATTERN OFF THE W COAST OF THE UNITED 
STATES IS FINALLY BREAKING AS WITH THE CUT-OFF LOW NOW MOVING 
EWD ACROSS SRN CALIFORNIA AND NRN BAJA CALIFORNIA. A WEAK 
SURFACE TROUGH IS ASSOCIATED WITH THIS FEATURE AND EXTENDS FROM 
SW ARIZONA TO 24N120W...AND THERE IS A SLIGHT AIR MASS CHANGE 
BEHIND IT AS DRIER/COOLER AIR SLIDES S. FARTHER W...A COMPLEX 
AND MASSIVE CYCLONIC TROUGH IS CENTERED N OF HAWAII WITH 
SHORTWAVE IMPULSES ROTATING NE AND JUST MISSING THE DISCUSSION 
AREA. A LARGE DIFFLUENT REGION LIES E OF THE TROUGH AND IS 
PRODUCING WIDESPREAD MID/UPPER LEVEL CLOUDINESS N OF 20N W OF 
125W. NEARLY ZONAL FLOW AND A LACK OF DEEP MOISTURE S OF 20N HAS 
KEPT THE ENVIRONMENT MOSTLY FAIR WITH THE EXCEPTION OF A FEW 
TSTMS ALONG THE ITCZ.

A MID-LEVEL HIGH REMAINS PLASTERED OFF THE CENTRAL AMERICAN 
COAST NEAR 10N92W WITH MODERATE/STRONG SUBSIDENCE DOMINATING THE 
REGION. SOME DIFFLUENCE ON THE SW PERIPHERY OF THE HIGH IS 
ENHANCING ITCZ CONVECTION ALTHOUGH OVERALL THE ENVIRONMENT IS 
RELATIVELY DRY. GAP WINDS...WITH THE EXCEPTION OF THE GULF OF 
PAPAGAYO...ARE SLOWLY DIMINISHING AS HIGH PRES WEAKENS OVER THE 
GULF OF MEXICO/CARIBBEAN.

$$
NELSON