Severe Thunderstorm Warning 279, NWS Kansas City, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
455 PM CDT FRI SEP 7 2001

A DEEP TROUGH OVER THE CENTRAL UNITED STATES WILL PROVIDE ACTIVE
WEATHER FOR THE WEEKEND. THE FIRST OF A PAIR OF SHORTWAVES PASSED
THROUGH THE REGION LAST EVENING. TIMING THE SECOND WILL PROVIDE THE
MAIN FORECAST CHALLENGE FOR THIS PACKAGE.

MODELS INITIALIZED SIMILARLY...BUT DIFFERENCES ARISE IN HANDLING
THE STRENGTH AND SPEED OF THE SHORTWAVE DIVING INTO COLORADO. I GAVE
PREFERENCE TO THE AVIATION MODEL. THE FASTER...MORE OPEN SOLUTION
SHOULD VERIFY BETTER WITH A FAST NORTHERLY FLOW. THE KICKER FOR THE
SYSTEM WAIL BE A POTENT UPPER LOW CURRENTLY MOVING THROUGH NWRN
CANADA. THE FASTER SOLUTION SHOULD MEAN THAT THE THREAT OF SHOWERS
SHOULD END OVER NRN MO BY EARLY IN THE AFTERNOON ON SUNDAY.

AREAL COVERAGE FOR THE SHOWERS SHOULD BE PRETTY SUBSTANTIAL. THE
DEEP LAYER MOISTURE AND INSTABILITY AVAILABLE TO THE EVENT LAST
EVENING WILL BE SOUTH OF THE FORECAST AREA ON SUNDAY...BUT THE
VIGOROUS NATURE OF THE SYSTEM SHOULD ALLOW FOR GOOD COVERAGE. THE
RIGHT ENTRANCE REGION OF 100KT JET...STRONG CONVERGENCE OF
Q-VECTORS...AND A ISENTROPIC LIFT OVER THE FRONT AT 850MB SHOULD
COME TOGETHER EARLY SUNDAY MORNING. THE ONLY THING PREVENTING ME
FROM INSERTING CATEGORICAL POPS INTO THE SRN TIER IS TIMING. ARRIVAL
OF THE RAIN WILL LIKELY BE WITHIN A FEW HOURS OF SUNRISE. FOR THE
NWRN MO AND NERN KS DEEP LAYER MOISTURE IS NOT AS ABUNDANT...SO HIGH
CHANCE POPS WILL DO FOR NOW.

SUNDAY NIGHT WILL BE THE COOLEST NIGHT IN MONTHS. SKIES SHOULD BE
CLEAR FOR THE MAJORITY OF THE NIGHT. I PREFER THE COOLER AVIATION
GUIDANCE...AND UPPER 40S ARE POSSIBLE NORTH OF HIGHWAY 36 WITH A
COOL AND DRY AIRMASS HEADED THIS WAY.

NEXT WEEK LOOKS DRY. LOW LEVEL MOISTURE FROM THE GULF WILL BE SLOW
TO RETURN. MRF PROGS 850MB FLOW OUT OF THE NW THROUGH THURS. HAVE
MADE NO CHANGES TO THE EXTENDED.

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

KOCH

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-043
>046-053-054-081100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
100 PM CDT FRI SEP 7 2001

FORECAST:  STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED ACROSS THE
ENTIRE REGION...STARTING OVER FAR NORTHWEST MISSOURI AND NORTHEAST
KANSAS LATE THIS AFTERNOON AND SPREADING EASTWARD OVERNIGHT. LARGE
HAIL AND DAMAGING WINDS WILL BE THE PRIMARY SEVERE WEATHER THREATS.
IN ADDITION...VERY HEAVY RAINFALL IS LIKELY WITH THE STRONGER
STORMS...WITH THE BEST CHANCE FOR HEAVY RAINFALL WEST OF A PAOLA
KANSAS TO ODESSA TO PRINCETON LINE.

EMERGENCY MANAGERS AND LAW ENFORCEMENT AGENCIES SHOULD STAY TUNED TO
LOCAL THEIR LOCAL MEDIA FOR THE LATEST FORECASTS AND STATEMENTS.
SPOTTER ACTIVATION MAY BE NECESSARY.

DISCUSSION:  A STRONG COLD FRONT WILL MOVE INTO EASTERN KANSAS AND
EXTREME NORTHWEST MISSOURI THIS EVENING. AN AREA OF LOW PRESSURE
IS EXPECTED TO FORM OVER NORTHERN OKLAHOMA AND LIFT NORTHEAST ALONG
THIS FRONT DURING THE EVENING HOURS. STRONG TO SEVERE THUNDERSTORMS
ARE EXPECTED TO INITIALLY FORM ALONG THIS FRONT AND AHEAD OF THE
LOW AFTER 3 PM. THE AIRMASS IS FORECAST TO BECOME VERY UNSTABLE THIS
AFTERNOON AND WILL BE CAPABLE OF SUPPORTING SEVERE WEATHER. A SQUALL
LINE IS EXPECTED TO EVOLVE QUICKLY ACROSS EASTERN KANSAS AND FAR
NORTHWEST MISSOURI. INDIVIDUAL STORMS WILL RACE NORTHEAST WHILE
THE COLD FRONT SHIFTS EASTWARD SLOWLY...REACHING A MILAN TO MOUND
CITY KANSAS LINE BY SATURDAY MORNING. DUE TO THE HIGH WATER CONTENT
OF THE ATMOSPHERE AND THE SLOW MOVEMENT OF THE COLD FRONT VERY HEAVY
RAINFALL IS LIKELY...WITH 2 TO 4 INCHES POSSIBLE ACROSS PARTS OF
NORTHERN AND WESTERN MISSOURI AND EXTREME EASTERN KANSAS.

OUTLOOK:  THE COLD FRONT IS EXPECTED TO STALL OVER SOUTHEAST KANSAS
AND CENTRAL MISSOURI SATURDAY NIGHT...SETTING THE STAGE FOR
ADDITIONAL SHOWERS AND THUNDERSTORMS SATURDAY NIGHT AND SUNDAY.

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

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