Severe Thunderstorm Warning 311, NWS Kansas City, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
205 PM CDT SAT SEP 22 2001

WV IMAGERY AND UPPER AIR ANALYSIS INDICATE LONGWAVE TROUGH OVER
EASTERN CONUS...WITH LARGE SCALE RIDGE OVER THE WEST. VIGOROUS
SHORTWAVE TROUGH DIGGING THROUGH DAKOTAS ALONG BACK SIDE OF LARGER
SCALE TROUGH. COLD FRONT ASSOCIATED WITH THIS FEATURE LOCATED ACROSS
CENTRAL NE BACK INTO NW KANSAS ATTM. ELEVATED CONVECTION IN REGION
OF WAA AHEAD OF THIS FRONT CURRENTLY ACROSS NW PORTION OF CWA BACK
INTO NORTHEAST KANSAS. DONT EXPECT MUCH FROM THIS BATCH OF
CONVECTION AS IT MOVES INTO MORE STABLE AIRMASS CURRENTLY IN PLACE
ACROSS MUCH OF CWA.

COLD FRONT PROGGED BY MODELS TO MOVE THROUGH CWA TONIGHT. SOME
DIFFERENCES IN TIMING OF FRONT BETWEEN AVN AND ETA MODELS. SURFACE
FRONT CURRENTLY ORIENTED NNE-SSW...AND SSE TRAJECTORY OF VORT MAX
DIGGING INTO NORTHERN PLAINS SEEMS TO SUPPORT SLOWER FORWARD
PROGRESS OF FRONT...SO WILL SIDE WITH TIMING OF ETA/META. THIS WOULD
BRING FRONT INTO CWA AROUND MIDNIGHT...THEN THROUGH METRO SOMETIME
AFTER MIDNIGHT. WITH SLOWER TIMING OF FRONT...APPEARS CHANCE OF
SEVERE WX WILL BE LOW. OTHER FORECAST PROBLEM WITH SLOWER FRONT
BECOMES OVERNIGHT LOWS. WILL BUMP OVERNIGHT LOWS A LITTLE FROM
PREVIOUS FORECAST AS COLDER H85 AIR DOESNT MOVE INTO AREA UNTIL
SUNDAY.

WILL KEEP MENTION OF LINGERING MORNING SHOWERS ACROSS ALL BUT
NORTHWEST CORNER OF CWA TOMORROW...WITH BEST CHANCE NEAR DMO. META
PUSHES FRONT OUT OF CWA BY EARLY AFTERNOON. STRONG SUBSIDENCE BEHIND
FRONT SHOULD RESULT IN SKIES BECOMING MOSTLY SUNNY BY AFTERNOON
ACROSS MUCH OF CWA. H85 TEMPS COOL 12-14C OVER TODAY...SO WILL GO
WITH HIGHS IN THE LOW TO MID 60S. SURFACE HIGH BUILDS INTO REGION
SUNDAY NIGHT...AND H85 TEMPS COOL TO AROUND 4-6C. DRY AIR BEHIND
FRONT AND LIGHT SURFACE GRADIENT WILL ALLOW OVERNIGHT LOWS TO DROP
INTO THE UPPER 30S/LOW 40S SUNDAY NIGHT.

UPPER LOW PROGGED TO CUT OFF OVER EASTERN US...WITH CWA REMAINING IN
DRY NORTHERLY FLOW THROUGH THE UPCOMING WEEK. POTENTIAL FLY IN THE
OINTMENT COMES FRI/SAT AS MRF/AVN UNDERCUT WESTERN RIDGE WITH CUTOFF
LOW EJECTING FROM EPAC...THEN DIG THIS FEATURE THROUGH CWA INTO
LARGE SCALE EASTERN TROUGH. ENSEMBLES AND EUROPEAN MODELS DONT SEEM
TO SUPPORT THIS IDEA...SO WILL KEEP FORECAST DRY INTO THE WEEKEND
FOR NOW.

.EAX...
KS...NONE.
MO...NONE.

SEAMAN

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-231100-

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE KANSAS CITY-PLEASANT HILL MO
850 PM CDT SAT SEP 22 2001

...SEVERE STORMS POSSIBLE MAINLY LATE THIS EVENING AND DURING
   THE EARLY MORNING HOURS OF SUNDAY...

FORECAST: SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS WILL CONTINUE
THROUGH THE EVENING HOURS...BUT THE THREAT OF SEVERE WEATHER WILL NOT
BEGIN UNTIL 10 OR 11 PM. STORMS ARE EXPECTED TO BUILD IN SOUTHEASTERN
NEBRASKA AND NORTHEAST KANSAS BY 10 PM...AND THEN MAY BEGIN TO MOVE
INTO EXTREME NORTHEAST KANSAS AND NORTHWEST MISSOURI. BETWEEN 10 PM AND
MIDNIGHT...THE THREAT OF SEVERE STORMS WILL BE GENERALLY WEST OF
A GRANT CITY MISSOURI ATCHISON KANSAS LINE...WITH THE THREAT SPREADING
SOUTHEAST INTO WEST CENTRAL MISSOURI BETWEEN MIDNIGHT AND 2 AM. STORMS
WILL CONTINUE TO PLUNGE SOUTHWARD...REACHING THE MARSHALL...WARRENSBURG
...HARRISONVILLE AND OSAWATOMIE AREAS BETWEEN 2 AND 4 AM. CENTRAL AND
NORTHEAST MISSOURI...WILL BE THE LEAST LIKELY AREA TO SEE SEVERE
WEATHER TONIGHT. THE MAIN THREATS FROM THESE STORMS WILL BE LARGE HAIL
AND DAMAGING WINDS. SPOTTER ACTIVATION MAY BE NECESSARY...SO STAY TUNED
FOR UPDATES.

DISCUSSION:  A STRONG COLD FRONT WILL BE MOVING THROUGH MISSOURI
OVERNIGHT. AHEAD OF THIS FRONT...STRONG STORMS ARE EXPECTED TO
DEVELOP. THE FRONT WILL STRETCH FROM NORTHEAST MISSOURI INTO
NORTHEAST OKLAHOMA BY SUNDAY MORNING...ALLOWING COLDER AIR TO MOVE
IN FOR THE END OF THE WEEKEND.

OUTLOOK:  NEXT WEEK SHOULD BE COOL AND DRY...WITH BELOW NORMAL
TEMPERATURES EXPECTED.

FOR ADDITIONAL WEATHER INFORMATION, CHECK OUR WEB SITE AT
HTTP://WWW.CRH.NOAA.GOV/EAX

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