000
AXPZ20 KNHC 170922
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI AUG 17 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN
FROM THE EQUATOR TO 32N...EAST OF 140W. 

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0845 UTC.

...TROPICAL WAVES...

TROPICAL WAVE ALONG 106W N OF 5N IS MOVING W AT 10 TO 15 KT 
SCATTERED CONVECTION MAINLY ALONG THE MEXICAN COAST. NO 
ORGANIZATION AT PRESENT TIME. STRONG NE AND E WINDS ALOFT OVER 
AREA PRECLUDES ANY DEVELOPMENT.

TROPICAL WAVE ALONG 127W FROM 5N TO 16N IS MOVING W AT 10 KT. 
NO EVIDENCE OF A WAVE AT THIS TIME.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG 8N80W 16N102W 12N117W 13N127W 
10N135W 11N140W. SCATTERED MODERATE CONVECTION NEAR 6N82W 7N91W 
8N96W AND 8N99W. SCATTERED MODERATE WITHIN 30 NM EITHER SIDE OF 
A LINE FROM 13N103W TO 11N113W TO 12N123W. ISOLATED MODERATE 
NEAR 13N129W.

SCATTERED STRONG CONVECTION NEAR THE COAST FROM 5N80W TO 7N80W 
AND FROM 9N86W TO 12N90W AND FROM 14N97W TO 20N108W TO 22N106W.

...DISCUSSION...

THE MAIN MID LEVEL FEATURE IS A RIDGE OF HIGH PRES CENTERED OVER 
THE SRN CONUS TONIGHT BUT EXTENDING WSW ACROSS THE REGION TO A 
SECONDARY CENTER NEAR 25N136W. IN BETWEEN LIES A INVERTED TROUGH 
ALONG 120W. A WEAK VORTICITY CENTER CAN BE SEEN IN WATER VAPOR 
IMAGERY NEAR 22N6N120.4W NEARLY STATIONARY. A LARGE MID LEVEL 
CYCLONIC CIRCULATION WELL N OF THE AREA ALONG 130W BARELY 
BRUSHES THE REGION ALONG 30N. DEEP LAYER MOISTURE CAN BE SEEN IN 
THE WATER VAPOR IMAGERY E OF 115W AND ALONG THE ITCZ S OF 13N. 
ON THE SURFACE TONIGHT THE PACIFIC RIDGE CENTERED NW OF THE AREA 
NEAR 37N157W RIDGES SE OVER THE AREA TO 116N110W. A WEAK LOW 
1007 MB WAS NEAR 16N107W AND UNDER THE INVERTED TROUGH THUS NOT 
MOVING MUCH. THE GFS MODEL HAS BEEN CONSISTENT ON DEVELOPING 
THIS SYSTEM BUT IT WILL BE A SLOW PROCESS. WINDS ALONG THE BAJA 
COAST ARE NWLY 10 TO 15 KT AND GAP WINDS ARE ALSO LIGHT. CROSS 
EQUATORIAL SLY WINDS ARE STRONGEST BETWEEN 8N AND 12N FROM 100W 
TO 123W ACCORDING TO QUIKSCAT AND SSMI IMAGERY. 

LATER DAY 1 THE MID LEVEL RIDGE OVER THE SRN CONUS WILL REMAIN 
STATIONARY WHILE THE SEPARATE BUBBLE NEAR 25N 136W DRIFTS WWD. 
THE INVERTED TROUGH DRIFTS W TO 122W WHILE THE STRONG CYCLONIC 
CIRCULATION REMAINS JUST N OF THE AREA ALONG 130W. ON THE 
SURFACE LATER DAY 1 THE PACIFIC RIDGE WILL MAINTAIN N AND NE 
WINDS TO 20 KT OVER THE REGION N OF 12N AND W OF 120W. WINDS 
ALONG THE BAJA COAST WILL REMAIN LIGHT ALTHOUGH SE WINDS COULD 
INCREASE ALONG THE W COAST OF MEXICO NEAR MANZANILLO WITH THE 
WEAK LOW SITUATED NEAR 16N108W. OTHERWISE GAP WINDS SHOULD 
REMAIN LIGHT. CROSS EQUATORIAL SLY WINDS SHOULD BE NEAR 20 KT 
BETWEEN 105W AND 125W WITH SE SWELL OF 8 FT. 

FOR DAY 2 THE MID LEVEL RIDGE WILL REMAIN OVER THE SRN CONUS 
EXTENDING W OVER BAJA. THE INVERTED TROUGH CONTINUES IT'S WWD 
DRIFT TO 126W WHILE THE BUBBLE OF HIGH PRES AT MID LEVELS DRIFTS 
WWD TO 25N145W. A SHORTWAVE TROUGH DROPS SE IN THE LARGE SCALE 
UPPER TROUGH ALONG 130W AND LOWERS MID LEVEL HEIGHTS ALONG 128W 
AND N OF 27N. ON THE SURFACE DAY 2 THE WEAK LOW DRIFTS NW TO 
NEAR 18N110W AND WILL CONTINUE TO HAVE WINDS TO 20 KT. INTERESTS 
AROUND LOWER BAJA SHOULD MONITOR THIS SYSTEM FOR ANY 
DEVELOPMENT. LITTLE CHANGE TO THE PACIFIC RIDGE WITH NE TRADES 
TO 20 KT N OF 11N W OF 125W. GAP WINDS SHOULD REMAIN LIGHT. 
CROSS EQUATORIAL SLY WINDS TO 20 KT EXPECTED BETWEEN 108W AND 
120W.  

$$
RRG