000
AXPZ20 KNHC 200915
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SAT OCT 20 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 FEATURE...
TROPICAL STORM KIKO NEAR 17.7N 106.1W OR ABOUT 117 NM SOUTHWEST 
OF MANZANILLO MEXICO AND ABOUT 379 MILES SOUTHEAST OF CABO SAN 
LUCAS MEXICO AT 0900 UTC. MAXIMUM SUSTAINED WINDS ARE 50 KT WITH 
GUSTS TO 60 KT WITH ESTIMATED MINIMUM CENTRAL PRESSURE IS 996 
MB. KIKO IS MOVING TOWARD THE NORTHWEST AT 4 KT. A TROPICAL 
STORM WATCH REMAINS IN EFFECT FOR PORTIONS OF THE PACIFIC COAST 
OF MEXICO FROM MANZANILLO TO CABO CORRIENTES. INTERESTS 
ELSEWHERE ALONG THE PACIFIC COAST OF MEXICO AND THE SOUTHERN 
PORTION OF BAJA CALIFORNIA SHOULD MONITOR THE PROGRESS OF KIKO. 
THIS TROPICAL CYCLONE IS EXPECTED TO PRODUCE RAINFALL 
ACCUMULATIONS OF 4 TO 7 INCHES OVER SOUTHWESTERN MEXICO WITH 
POSSIBLE ISOLATED AMOUNTS OF 10 INCHES. SEE LATEST NHC FORECAST 
ADVISORY UNDER AWIPS/WMO HEADERS MIATCMEP5/WTPZ25 KNHC FOR 
ADDITIONAL DETAILS.

...ITCZ...
INTERTROPICAL CONVERGENCE ZONE ALONG 13N84W 17N91W 12N98W 9N128W 
7N140W. SCATTERED MODERATE CONVECTION NEAR 3N79W 9N85W AND 
12N91W. SCATTERED STRONG NEAR 14N95W. ISOLATED MODERATE NEAR 
10N120W AND 9N125W.

...DISCUSSION...

ANOTHER SWIFT MOVING UPPER TROUGH IN WESTERLIES TONIGHT MOVING 
BY THE AREA ALONG 125W. MID LEVEL RIDGE OVER NRN MEXICO AND 
ANOTHER ONE W OF THE AREA NEAR 26N146W. A WEAKNESS IN THE MID 
LEVELS BETWEEN THE TWO ALONG 118W. ON THE SURFACE TONIGHT T.S. 
KIKO NEARLY STATIONARY THE PAST FEW HRS ABOUT 180 NM SSW OF 
MANZANILLO MEXICO. SYSTEM IS LOOKING A LITTLE BETTER THAN LAST 
NIGHT WITH CONVECTION STARTING TO CIRCLE THE CENTER. THE PACIFIC 
RIDGE NW OF THE AREA RIDGES SE TO 15N115W. THE RIDGE IS 
PRODUCING NE TRADES OF 20 KT N OF 10N W OF 125W AND A NLY WIND 
OF 20 TO 25 KT N OF 25N BETWEEN 120W AND 127W WITH INCREASING 
NLY SWELL TO 10 FT ACCORDING TO SHIP OBS. GAP WINDS REMAIN 
LIGHT. CROSS EQUATORIAL SW WINDS CONTINUE TO PUSH THE ITCZ UP 
AGAINST THE COAST OF CENTRAL AMERICA. SSMI AND QUIKSCAT SHOW 
WINDS SWLY 20 KT E OF 105W. ELSEWHERE SLY WINDS TO 20 KT ARE 
EVIDENT S OF THE ITCZ BETWEEN 105W AND 140W WITH SLY SWELL TO 8 
FT.

LATER DAY 1 SLIGHT LOWERING OF MID LEVEL HEIGHTS BETWEEN 110W 
AND 120W AS THE FAST MOVING UPPER TR0UGH MOVES BY TO THE N AND 
INLAND OVER THE WRN CONUS. MID LEVEL RIDGES HOLDING THEIR OWN 
BUT BOTH MOVING SLOWLY EWD. ON THE SURFACE LATER DAY 1 ALL 
INTERESTS ALONG THE WRN MEXICAN COAST AND LOWER BAJA PENINSULA 
SHOULD KEEP AN EYE ON T.S. KIKO. KIKO IS FORECAST TO SLOWLY 
DEVELOP AS IT MOVES NW. PACIFIC RIDGE RE-ORIENTS ITSELF NEAR 
35N135W WITH RIDGE AXIS SSW. THIS WILL TIGHTEN THE GRADIENT N OF 
26N BETWEEN 118W AND 128W WITH INCREASING NLY WINDS AND NLY 
SWELL. LITTLE CHANGE ELSEWHERE.

FOR DAY 2 GFS MODEL SHOWS UPPER TROUGH DIVING SE OVER SWRN CONUS 
LOWERING HEIGHTS OVER NRN MEXICO. THIS WILL SHOVE THE MID LEVEL 
RIDGE OVER NRN MEXICO EWD WHILE THE WRN RIDGE BUILDS ALONG 130W 
NWD. THIS SHIFT IN MID LEVEL PATTERN WILL MOVE THE WEAKNESS EWD 
OVER MEXICO AND AFFECT THE MOVEMENT OF KIKO.  KIKO IS FORECAST 
TO BECOME A CATEGORY ONE HURRICANE NEAR 20N108W AND ALL 
INTERESTS ALONG THE WRN MEXICAN COAST AND LOWER BAJA PENINSULA 
SHOULD MONITOR KIKO CLOSELY. GAP WINDS REMAIN LIGHT. CROSS 
EQUATORIAL WINDS DECREASE E OF 105W AS SURFACE PRESSURES SLOWLY 
RISE OVER CENTRAL AMERICA. W OF 105W CROSS EQUATORIAL SLY WINDS 
REMAIN ABOUT THE SAME. 

$$
RRG