000
AXPZ20 KNHC 030918
TWDEP 

TROPICAL WEATHER DISCUSSION      
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC FRI AUG 03 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.

...SPECIAL FEATURES...
NONE.

...TROPICAL WAVE...
TROPICAL WAVE ALONG 86W MOVING W 5 TO 10 KT. SCATTERED MODERATE 
CONVECTION IS OCCURING OVER THE CARIBBEAN AND E PACIFIC E OF THE 
WAVE AXIS. THERE IS NO ORGANIZATION TO THE CONVECTION AT THIS 
TIME. 
 
TROPICAL WAVE ALONG 98W MOVING W 10 KT. THERE IS SCATTERED 
STRONG CONVECTION JUST E OF THE WAVE AXIS AND WITHIN 120 NM OF 
THE MEXICAN COAST AND WITH A WEAK LOW CENTER ON THE ITCZ JUST W 
OF THE WAVE AXIS.   

TROPICAL WAVE ALONG 119W MOVING W 10 TO 15 KT. SCATTERED 
MODERATE AND ISOLATED STRONG CONVECTION WITHIN 180 NM OF 
16N120W. THERE APPEARS TO BE CYCLONIC ROTATION TO THE MID LEVEL 
CLOUDS AND ANTI-CYCLONIC OUTFLOW IS EVIDENT ON THE N SIDE OF 
THIS CIRCULATION. 

...ITCZ...
ITCZ AXIS IS CENTERED ALONG...8N78W 8N99W 15N115W 14N120W 
14N131W 10N140W. SCATTERED MODERATE AND ISOLATED STRONG 
CONVECTION WITHIN 45 NM OF A LINE FROM 5N77W TO 7N84W TO 9N101W 
TO 9N112W. SCATTERED MODERATE TO STRONG CONVECTION WITHIN 180 NM 
OF 16N120W. SCATTERED MODERATE WITHIN 120 NM OF 13N127W AND 
12N137W. 

.SCATTERED MODERATE AND STRONG CONVECTION WITHIN 60 NM OF THE 
COAST FROM 8N84W TO 13N90W TO 15N95W TO 16N100W TO 19N104W.

...DISCUSSION...

TWO MAIN PLAYERS AT MID LEVELS TONIGHT CONTINUE TO BE RIDGES OF 
HIGH PRESSURE. BOTH ARE ACTING AS BLOCKS TO TROUGH MOVEMENT. ONE 
IS OVER THE SW CONUS AND WATER VAPOR SHOWS THE AXIS OF THE RIDGE 
ALONG 106W. THE OTHER RIDGE IS CENTERED NEAR 30N140W. IN BETWEEN 
IS AN OLD INVERTED TROUGH ALONG 127W AND WATER VAPOR IMAGERY 
SHOWS THIS SYSTEM NEARLY STATIONARY WITH NO HIGH LEVEL MOISTURE 
TO WORK WITH.  MID LEVEL EASTERLIES ARE CONFINED TO S OF 20N 
TONIGHT WITH WEAK VORTICITY CENTERS ALONG 8N TO 16N. ON THE 
SURFACE TONIGHT THE PACIFIC RIDGE IS ANCHORED BY A 1028 MB HIGH 
NEAR 34N142W AND RIDGES SE OVER THE REGION TO 18N110W. A SURFACE 
TROUGH IS MOVING INTO THE AREA ALONG NEAR 30N128W AND COULD 
INCREASE NLY SWELL AND WINDS TO 20 KT. DISTURBANCES ALONG THE 
ITCZ ARE ACTIVE WITH ONE NEAR 105W AND ANOTHER NEAR 120W. OLD 
T.S. ERICK HAS DISSIPATED INTO A REMNANT LOW NEAR 13N136W STILL 
MOVING W. WINDS ALONG THE BAJA COAST ARE LIGHT NWLY ACCORDING TO 
SSMI IMAGERY AND IN GOOD AGREEMENT WITH THE GFS MODEL. GAP WINDS 
ARE ALSO LIGHT. CROSS EQUATORIAL SLY WINDS ARE STRONGEST S OF 
CONVECTION ON THE ITCZ. SSMI SHOWS AREAS OF 20 KT BETWEEN 90W 
AND 105W AND SE WINDS TO 20 KT W OF 110W. 

LATER DAY 1 THE WESTERLIES SEND IN THE CALVARY TO RESCUE TO 
EMBEDDED TROUGH ALONG 126W IN FORM OF A SHORTWAVE TROUGH. THE 
GFS MODEL SHOWS THE TWO APPROACHING JUST N OF THE AREA ALONG 
128W. ANOTHER EMBEDDED SHORTWAVE MOVES WSW ACROSS NRN MEXICO AND 
WILL ROTATE AROUND THE RIDGE OVER THE SW CONUS AND PROBABLY TAKE 
THE PLACE OF THE TROUGH LIFTING N. ON THE SURFACE LATER DAY 1 
THE TROUGH MOVING INTO THE NRN PORTION OF THE AREA GRADUALLY 
DISSIPATES. WITH THE PACIFIC RIDGE CENTER NW OF THE AREA..NE 
TRADES ARE STRONGEST N OF 25N AND W OF 135W AT 20 KT. LITTLE 
CHANGE ELSEWHERE.

FOR DAY 2 THE MID LEVEL RIDGES REMAIN IN PLACE WITH THE TROUGH 
IN BETWEEN LIFTING NWD ALONG 130W. THE EMBEDDED SHORTWAVE S OF 
THE SW CONUS RIDGE CONTINUES WWD TO 110W AND WILL WORK IT'S WAY 
INTO THE WEAKNESS BETWEEN 120W AND 130W IN THE NEXT DAY OR TWO. 
ON THE SURFACE DAY 2 THE GFS MODEL SHOWS DISTURBANCES ALONG THE 
ITCZ TRYING TO GET MORE ACTIVE WITH THE STRONGEST ONE NEAR 
10N112W. THIS WILL INCREASE SLY CROSS EQUATORIAL WINDS BETWEEN 
105W AND 115W TO 20 TO 25 KT. OTHERWISE LITTLE CHANGE ELSEWHERE.

$$
RRG