Severe Thunderstorm Warning 187, NWS Kansas City, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
412 AM CDT TUE AUG 24 2004

.DISCUSSION...

THE MAIN FOCUS FOR THIS MORNINGS FORECAST IS ON THE CONVECTION AND
THE FLOOD POTENTIAL FOR THE NEXT 36 HOURS.

OVERNIGHT...THUNDERSTORM ACTIVITY FIRED ACROSS A SURFACE WARM FRONT
ALONG INTERSTATE 70 IN EASTERN KANSAS...BUT STRUGGLED TO PUSH EAST
INTO THE PLEASANT HILL CWA. THE AIRMASS OVER EXTREME EASTERN KANSAS
AND WESTERN MISSOURI HAD BEEN WELL WORKED OVER BY STORMS THROUGHOUT
THE DAY MONDAY. THE SHORTWAVE...THAT WAS SUPPORTING THE ACTIVITY IN
EAST KANSAS...BEGAN SHIFTING EAST WITH THE HELP OF THE NOSE OF THE
SUBTROPICAL JET LATE MONDAY NIGHT. MEANWHILE...THE STORMS OVER
TOPEKA AND LAWRENCE DEVELOPED A MESO HIGH. THESE FACTORS THEN
CONSPIRED TO PUSH THE CONVECTION THROUGH THE CWA DURING THE EARLY
MORNING HOURS. THE EFFECTIVE SURFACE FRONT WAS SHOVED WELL SOUTH BY
THE MESO HIGH...BUT CONVECTION HAS BEGUN TO REDEVELOP ACROSS
NORTHEAST KANSAS AND NORTHWEST MISSOURI AS THE LOW LEVEL JET
ENHANCED ISENTROPIC LIFT ACROSS AN ELEVATED 850MB BOUNDARY.

THE ONGOING ACTIVITY EARLY THIS MORNING IS ANTICIPATED TO SLOWLY
DECREASE AFTER SUNRISE AS THE LOW LEVEL JET VEERS IN RESPONSE TO THE
EXITING SHORT WAVE. FOR THE AFTERNOON...THE TELLING DETAIL WILL BE
HOW EFFECTIVE THE MID LATITUDE AND SUBTROPICAL JETS INTERACT ACROSS
EASTERN KANSAS AND SOUTHERN NEBRASKA. BOTH THE GFS AND ETA INDICATE
THAT THE ENTRANCE AND EXIT REGIONS FROM THESE JETS WILL MAKE FOR
SIGNIFICANT STORM TOP DIVERGENCE ACROSS NORTHERN KANSAS AND SOUTHERN
NEBRASKA...SPARKING CONVECTION THAT WITH THEN ROLE INTO NORTH
MISSOURI OVERNIGHT. WHILE I BEGIN THE OVERNIGHT HOURS WITH A CHANCE
OF THUNDER ACROSS MOST OF THE CWA...I HAVE RESTRICTED THE HIGHEST
POPS TO THE NORTHWEST CORNER BEFORE MIDNIGHT...AND THE MISSOURI IOWA
BORDER FOR THE AFTER MIDNIGHT TIME FRAME.

ADDITIONALLY...TONIGHTS EXPECTED CONVECTION STANDS A FAIR CHANCE OF
PRODUCING MORE HEAVY RAIN...ESPECIALLY ACROSS NORTHERN MISSOURI
WHERE THE SURFACE BOUNDARY IS EXPECTED TO TAKE UP RESIDENCE LATER
TONIGHT. WITH PRECIPITABLE WATER VALUES RUNNING AROUND AN INCH AN A
HALF...AND THE POTENTIAL FOR AN MCS TO MOVE ALONG IT...A FLOOD WATCH
MIGHT BE NEEDED FOR LOCATIONS ALONG AND NORTH OF MISSOURI STATE
HIGHWAY 36. WORKING AGAINST THE NEED FOR A WATCH IS THE FACT THAT IT
HAS BEEN DRY ACROSS NORTHERN MISSOURI FOR A FEW WEEKS...AND THE
CONVECTION FROM THIS MORNINGS ACTIVITY WILL HAVE A DIRECT IMPACT ON
WHERE FLOODING WILL BE POSSIBLE LATER TONIGHT. THEREFORE...I WILL GO
WITH HYDROLOGIC OUTLOOK (ESF) FOR NORTHERN MISSOURI TONIGHT. THIS
WILL GIVE THE DAY SHIFT A CHANCE TO LOOK AT CO-OP RAINFALL REPORTS
ACROSS NORTHERN MISSOURI...AND GET A HANDLE ON WHERE A WATCH MIGHT
BE NEEDED.

CUTTER

&&

.PREVIOUS DISCUSSION...

947 PM MON...
QUICK UPDATE TO THE GOING FORECAST FOR THIS EVENING. THE
THUNDERSTORM ACTIVITY TO OUR WEST HAS STRUGGLED TO MOVE EAST ALL
EVENING DUE TO THE MORE STABLE AIR MASS FROM THIS MORNINGS AND
AFTERNOONS CONVECTION. HOWEVER...WITH THE SHORTWAVE VORT MAX RIGHT
ON TOP OF US...AND THE SUBTROPICAL JET PUSHING INTO EASTERN KANSAS
AND OKLAHOMA...THE ACTIVITY HAS FINALLY BEGUN TO PUSH EAST.
THEREFORE...I BUMPED POPS UP TO CATEGORICAL FOR THE SOUTHWEST
QUARTER OF THE CWA. THE THREAT OF SEVERE THUNDERSTORM ACTIVITY IS
ANTICIPATED TO CONTINUE THROUGH MIDNIGHT.

CUTTER

300 PM MON...
CONVECTIVE POTENTIAL THE NEXT COUPLE OF DAYS IS THE MAIN CONCERN.
SHORTWAVE TROUGH ACROSS EXTREME EASTERN KANSAS AND WRN MO CONTINUES
TO TRIGGER BANDS OF CONVECTION ACROSS THE CWA. ISENTROPIC LIFT ABOVE
OUTFLOW BOUNDARY IN SOUTHEAST KANSAS MAY ALSO BE RESPONSIBLE FOR THE
CONVECTION TO THE SOUTHWEST OF THE KC METRO AREA.

UNUSUAL PATTERN FOR LATE SUMMER WILL CONTINUE THE NEXT FEW DAYS WITH
A SERIES OF SHORTWAVES TO EJECT NORTHEAST FROM THE WESTERN US
TROUGH. FIRST CONCERN IS THE THREAT OF CONVECTION TONIGHT AS
ISENTROPIC LIFT DEVELOPS THROUGHOUT PORTIONS OF THE CWA. THE MESOETA
IS RATHER STRONG WITH THE ISENTROPIC LIFT ON THE 305-310K SURFACE
TONIGHT...BUT SUSPICIOUS OF ITS SUCH STRONG THERMAL GRADIENT. PREFER
WEAKER SOLUTION OF THE GFS/NGM. CWA ALSO LOCATED IN UPPER DIVERGENCE
ZONE AS STG H2 JET MOVES ACROSS OKLAHOMA AND ARKANSAS. AS PER THE
GFS...BEST ISENTROPIC LIFT TO OCCUR IN THE WESTERN ZONES AFTER
MIDNIGHT ALTHOUGH WEAK ISENTROPIC LIFT WILL BE PRESENT ACROSS THE
SRN AND WRN ZONES THIS EVENING. WILL KEEP PRECIPITATION IN THE
CHANCE CATEGORY AS EXACT LOCATION OF BEST ISENTROPIC LIFT IS IN
QUESTION...EXCEPT IN THE ERN ZONES NEAR CATEGORICAL THIS EVENING.

ISENTROPIC LIFT TO DIMINISH IN THE EASTERN ZONES TUESDAY MORNING
WITH A H7 CAP BUILDING INTO THE WRN ZONES DURING THE AFTERNOON. A
WEAK SHORTWAVE MAY TRIGGER CONVECTION DURING THE LATE AFTERNOON
HOURS ALONG A SURFACE TROUGH FROM CENTRAL NEBRASKA TO CENTRAL
KANSAS. PREFER SURFACE DEPICTION OF THE GFS AS MESOETA MAY BE
SUFFERING FROM CONVECTIVE FEEDBACK WITH ITS SURFACE BOUNDARY LOCATED
FROM SE NEBRASKA TO SRN IOWA. CONVECTION MAY HAVE A TOUGH TIME
DEVELOPING ALONG THE TROUGH IN CENTRAL KANSAS DUE TO THE CAP.
HOWEVER...THUNDERSTORMS WILL LIKELY DEVELOP IN NEBRASKA AND MOVE
INTO THE NORTHERN ZONES TUESDAY NIGHT.

CONVECTION MAY LINGER IN THE NORTHEAST ZONES WEDNESDAY MORNING. A
REPEAT PERFORMANCE MAY OCCUR WEDNESDAY AFTERNOON AND WEDNESDAY NIGHT
AS THE SURFACE TROUGH REMAINS RELATIVELY STATIONARY.
HOWEVER...BELIEVE THE THREAT WILL MAINLY STAY NORTH OF THE BORDER.

OTHERWISE...TEMPERATURES TRICKY AND DEPEND ON CONVECTION AND
CONVECTIVE OUTFLOW. OVERALL...TEMPERATURES TO WARM THE NEXT COUPLE
OF DAYS.

DB

IN THE EXTENDED PORTION OF THE FORECAST...THE GFS AND DGEX CONTINUE
TO FORECAST THE PROGRESSION OF A TROUGH ACROSS THE ROCKIES AND
CENTRAL PLAINS DURING THE LAST HALF OF THE WEEK. THE SURFACE
REFLECTION OF THIS FEATURE IS FORECAST TO PASS ACROSS THE FORECAST
AREA FRIDAY NIGHT INTO EARLY SATURDAY...AND HAVE PLACED THE HIGHEST
CHANCE POPS (40) DURING THIS TIMEFRAME. SOUTH/SOUTHWEST FLOW AHEAD
OF THIS SYSTEM WILL BRING ABOVE-NORMAL TEMPERATURES PRIOR TO THE
FRONTAL PASSAGE ON SATURDAY...AFTER WHICH NEAR OR SLIGHTLY
BELOW-NORMAL READINGS WILL PREVAIL OVER THE WEEKEND.

SCHMIT

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
MO...NONE.

WFO EAX

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
543 AM CDT TUE AUG 24 2004

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-251100-

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST...NORTH CENTRAL AND
WEST CENTRAL MISSOURI...AS WELL AS EXTREME EASTERN KANSAS.

.DAY ONE...TODAY AND TONIGHT

FOR THIS MORNING...ON GOING THUNDERSTORM ACTIVITY IN THE NORTHWEST
CORNER OF MISSOURI WILL SINK DUE SOUTH. WHILE THESE STORMS ARE NOT
EXPECTED TO PRODUCE ANY SEVERE WEATHER...THEY WILL BE CAPABLE OF
DROPPING HEAVY RAIN ACROSS EASTERN KANSAS AND WESTERN MISSOURI. THIS
IN COMBINATION WITH RAINFALL ALREADY RECEIVED WILL MAKE LOCALLY
INCONVENIENT FLOODING POSSIBLE THROUGH THE REMAINDER OF THE MORNING
FOR LOCATIONS FROM MOUND CITY MISSOURI AND MAYSVILLE SOUTH THROUGH
KANSAS CITY...PAOLA...AND HARRISONVILLE.

THE CHANCE OF THUNDERSTORM ACTIVITY WILL PERSIST THROUGH THE
AFTERNOON HOURS...BUT THE BEST POTENTIAL FOR SEVERE ACTIVITY WILL BE
SOUTH OF THE OUTLOOK AREA ALONG A SURFACE WARM FRONT IN SOUTHERN
MISSOURI.

OVERNIGHT...THE WARM FRONT WILL LIFT NORTH INTO EXTREME NORTHERN
MISSOURI. AS IT DOES SO IT WILL BEGIN TO INTERACT WITH A COMPLEX OF
THUNDERSTORMS SHIFTING EAST OUT OF SOUTHERN NEBRASKA. WITH ABUNDANT
MOISTURE ALREADY IN PLACE...THIS WILL SET THE STAGE FOR HEAVY
RAINFALL ACROSS NORTHERN MISSOURI. ADDITIONALLY... THERE WILL ALSO BE
A POSSIBILITY OF SOME THUNDERSTORMS PRODUCING SEVERE WEATHER...WITH
THE MAIN THREAT BEING LARGE HAIL AND DAMAGING WINDS. THE FOCUS OF ALL
THIS ACTIVITY WILL BE ALONG AND NORTH OF HIGHWAY 36.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

LINGERING THUNDERSTORM ACTIVITY WILL CONTINUE THROUGH THE DAY
WEDNESDAY. A FEW OF THESE STORMS MAY ALSO BECOME SEVERE.

THUNDERSTORMS ARE POSSIBLE FRIDAY NIGHT AND EARLY SATURDAY AS A COLD
FRONT AND UPPER LEVEL STORM MOVES THROUGH THE REGION. SEVERE
THUNDERSTORMS WILL AGAIN BE POSSIBLE POSSIBLE.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED TONIGHT FOR LOCATIONS ALONG AND
NORTH OF HIGHWAY 36 FROM ST JOSEPH TO CHILLICOTHE AND MACON...AND MAY
BE NEEDED AGAIN FRIDAY NIGHT AND SATURDAY AREA WIDE.

&&

THIS PRODUCT...ALONG WITH OTHER WEATHER...HYDROLOGIC AND CLIMATE
INFORMATION...IS AVAILABLE ON THE WEB AT (LOWER CASE)
HTTP://WWW.CRH.NOAA.GOV/EAX OR HTTP://WEATHER.GOV.

CUTTER

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
713 AM CDT TUE AUG 24 2004

..TIME...   ...EVENT...     ...CITY LOCATION...      ...LAT.LON...
..DATE...   ....MAG....     ..COUNTY LOCATION...ST.. ...SOURCE....
            ..REMARKS..

0709 AM     HAIL             LEAVENWORTH             39.32N 94.92W
08/24/2004  0.88 INCH        LEAVENWORTH        KS   EMERGENCY MNGR

&&

SCHMIT