River Flood Warning 74, NWS Kansas City, MO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
637 PM CDT WED APR 9 2008

...UPDATED FOR AVIATION DISCUSSION...

.DISCUSSION...
/442 PM CDT WED APR 9 2008/
SHORT TERM SITUATION SHAPING UP TO BE A SIGNIFICANT RAIN EVENT FOR
MUCH OF THE FORECAST AREA...ESPECIALLY WITH THE WET GROUND FROM THE
RAIN THAT FELL TUESDAY MORNING. WILL EXPAND THE FLOOD WATCH TO COVER
ALL BUT THE EXTREME NORTHWEST CORNER OF MISSOURI WHERE FLOOD
GUIDANCE NUMBERS ARE A LITTLE HIGHER. WITH THAT SAID...IF IT APPEARS
THAT AREA WILL BE GETTING OVER AN INCH AND A HALF OF RAINFALL...THE
FLOOD WATCH MAY HAVE TO BE EXTENDED INTO THAT REGION AS WELL.

WILL BE SEEING THE RAIN IN A COUPLE OF ROUNDS. FIRST ROUND TONIGHT
ALREADY STARTING TO MOVE INTO SOUTHEAST KANSAS AND SOUTHWEST
MISSOURI. THIS COMPLEX SHOULD CONTINUE TO EXPAND NORTHWARD AS THE
LLJ INCREASES TONIGHT. NAM MODEL THE FURTHEST NORTH WITH THIS JET.
ECMWF SUPPORTS THIS IDEA AS WELL BUT KEEPS THE DEEPEST MOISTURE
OVERNIGHT CHANNELED MORE FROM EAST CENTRAL KANSAS INTO NORTHEAST
MISSOURI. EXCESSIVE RAINFALL FROM HPC ALSO HIGHLIGHTS THIS AREA.

ANOTHER CONCERN WITH THIS SYSTEM IS THE SEVERE POTENTIAL. FIRST WILL
NEED TO GET SOME INSTABILITY FROM HEATING GOING IN THE AFTERNOON
WHICH WILL REQUIRE SOME CLEARING. MORNING CONVECTION MAY KEEP THINGS
PRETTY MUCKED UP. HOWEVER...MODELS DO SHOW A DRY LINE SETTING UP TO
THE WEST OF THE FORECAST AREA THAT MAY BE A FOCUS FOR STORM
DEVELOPMENT IN THE AFTERNOON. MAIN PROBLEMS WITH STORMS COMING INTO
WESTERN PORTIONS OF THE FORECAST AREA WILL BE THE VERY STRONG SHEAR.
IF THERE IS ENOUGH INSTABILITY...STORMS MAY BE ABLE TO HOLD TOGETHER
AND PRODUCE DAMAGING WINDS...BUT WITH SUCH A TILT TO THE
STORM...HAIL SEEMS LESS LIKELY. EASTERN PORTIONS OF THE CWFA...WHERE
THE SHEAR WILL BE A LITTLE LESS...THIS MAY BE A MORE FAVORABLE
ENVIRONMENT FOR ORGANIZED CONVECTION. ANOTHER CONCERN IS WITH THE
UPPER LOW AND TRIPLE POINT AT THE SURFACE MOVING ACROSS NORTHWEST
MISSOURI LATE IN THE AFTERNOON. THIS MAY BE A FAVORABLE SET UP FOR
LOW TOP SUPERCELLS.  THE WINDOW FOR THESE TYPES OF STORMS WILL BE
FAIRLY LIMITED IN THE LATE AFTERNOON AND WILL BE CONTINGENT ON
GETTING SOME CLEARING AND SURFACE HEATING.  SO BOTTOM LINE...IF THE
SUN START SHINING THURSDAY AFTERNOON...START GETTING CONCERNED ABOUT
SEVERE WEATHER.

THIS SYSTEM WILL LIFT INTO IOWA BY FRIDAY MORNING...BECOMING VERY
OCCLUDED WITH ELEVATED WARM AIR BEING WRAPPED WELL INTO THE SYSTEM.
COLDER AIR WILL BE SLIDING AROUND THE WESTERN EDGE AND INTO
NORTHWEST MISSOURI FRIDAY MORNING. SOUNDINGS SHOW TEMPERATURES WOULD
BE SUPPORTIVE OF SNOW IN NORTHWEST MISSOURI BY 12Z WITH THE
POTENTIAL OF SNOW DEVELOPING FURTHER TO THE EAST DURING THE DAY AS
THIS SYSTEM CONTINUES TO WIND UP. NOT GOING WITH ANY ACCUMULATIONS
AT THIS POINT WITH THE WARM GROUND...BUT SOMETHING THAT WILL NEED TO
BE WATCHED...ESPECIALLY TOWARD THE IOWA BORDER.

PC

IN THE MEDIUM RANGE FORECAST...FIRST HALF OF THE WEEKEND STILL
REMAINS ON TRACK TO BE UNSEASONABLY COLD WITH A LOW CHANCE FOR
SCATTERED RAIN/SNOW SHOWERS THROUGHOUT.  CONTINUED TO LOWER
TEMPERATURES ON SATURDAY AS MODEL TRENDS OF EVEN COLDER LOW-LVL
TEMPS APPEAR POSSIBLE.  SOUNDING INSPECTIONS WOULD POINT TO VERY
LIMITED WARMING...WITH THE LIKELIHOOD THAT THERE WILL BE POCKETS OF
WARMER TEMPERATURES WHERE SUNSHINE BREAKS THROUGH THE CLOUDS.
NUMERICAL GUIDANCE IS OF LITTLE VALUE IN THIS TYPE OF SITUATION.
THEREFORE WILL REMAIN WITH LOW-MID 40S OVER THE SOUTHERN HALF OF THE
CWA TO UPPER 30S NEAR THE IA BORDER.

ANY SUN THAT CAN BE SEEN WILL WORK TO INDUCE SCATTERED SHOWER
ACTIVITY.  PRECIP TYPE APPEARS TO BE MORE DOMINATED TOWARDS THE
FROZEN TYPE ATTM...HOWEVER WITH CONSIDERABLE UNCERTAINTY AS TO HOW
WARM THE LOWEST LAYERS OF THE ATMOS WILL BE...DECIDED TO LINGER WITH
A RA/SN MIX SOUTH OF I-70 IN THE AFTERNOON.

GRADUAL WARMUP WILL BEGIN IN EARNEST ON SUNDAY AS A DRY...MID-LVL
RIDGING MOVES OVERHEAD FOR THE BEGINNING OF THIS WEEK.  HOWEVER...AS
SFC RIDGE PASSES OVERHEAD SUNDAY AND MONDAY NIGHT CLEAR SKIES WILL
LEAD TO THE POTENTIAL OF PATCHY FROST OR BELOW FREEZING CONDITIONS
ESPECIALLY ACROSS THE NORTHERN HALF OF MISSOURI.  TEMPERATURES
MON-WED WILL LIKELY REMAIN AOA SEASONAL NORMALS.

DUX

&&

.AVIATION...
FOR THE 00Z TAF...MVFR CEILINGS WILL QUICKLY GIVE WAY TO AN
APPROACHING AREA OF RAIN WITH EMBEDDED THUNDERSTORMS WITH CEILINGS
GRADUALLY LOWERING TO AOB 2K FEET AGL AROUND 02Z AT THE KANSAS CITY
TERMINALS AND BY 04Z AT STJ. THE REST OF THE NIGHT WILL SEE RAIN
WITH OCCASIONAL THUNDERSTORMS PRODUCING PERIODS OF MODERATE TO HEAVY
RAINS. AFTER MIDNIGHT PREVAILING CEILINGS IN THE IFR CATEGORY
EXPECTED WITH ONGOING RAIN. STIFF EASTERLY WINDS IN THE MIDDLE TO
UPPER TEENS WILL BE IN PLACE OVERNIGHT AND THROUGH THURSDAY MORNING.
A WARM FRONT IS EXPECTED TO SURGE NORTH TOMORROW AND PASS THROUGH
ALL 3 TERMINALS EARLY IN THE AFTERNOON. THE EASTERLY WINDS WILL VEER
TO THE SOUTH. THE RAIN SHOULD GIVE WAY TO SCATTERED AFTERNOON
CONVECTION WITH THE POTENTIAL FOR STRONG TO SEVERE THUNDERSTORMS.
CEILINGS WILL IMPROVE TO MVFR WITH THE PASSAGE OF THE WARM FRONT IN
THE AFTERNOON.

MJ

&&

.EAX WATCHES/WARNINGS/ADVISORIES...
MO...FLOOD WATCH FROM 1 AM THURSDAY TO 1 AM FRIDAY FOR MOZ003-MOZ004-
     MOZ005-MOZ006-MOZ007-MOZ008-MOZ012-MOZ013-MOZ014-MOZ015-
     MOZ016-MOZ017-MOZ020-MOZ021-MOZ022-MOZ023-MOZ024-MOZ025-
     MOZ028-MOZ029-MOZ030-MOZ031-MOZ032-MOZ033-MOZ037-MOZ038-
     MOZ039-MOZ040-MOZ043-MOZ044-MOZ045-MOZ046-MOZ053-MOZ054.

KS...FLOOD WATCH FROM 1 AM THURSDAY TO 1 AM FRIDAY FOR KSZ025-KSZ057-
     KSZ060-KSZ102-KSZ103-KSZ104-KSZ105.

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
104 PM CDT WED APR 9 2008

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-101815-
ATCHISON KS-MIAMI-LINN KS-DONIPHAN-LEAVENWORTH-WYANDOTTE-
JOHNSON KS-ATCHISON MO-NODAWAY-WORTH-GENTRY-HARRISON-MERCER-
PUTNAM-SCHUYLER-HOLT-ANDREW-DE KALB-DAVIESS-GRUNDY-SULLIVAN-ADAIR-
BUCHANAN-CLINTON-CALDWELL-LIVINGSTON-LINN MO-MACON-PLATTE-CLAY-
RAY-CARROLL-CHARITON-RANDOLPH-JACKSON-LAFAYETTE-SALINE-HOWARD-
CASS-JOHNSON MO-PETTIS-COOPER-BATES-HENRY-
104 PM CDT WED APR 9 2008

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

.DAY ONE...THIS AFTERNOON AND TONIGHT

AN UPPER LEVEL DISTURBANCE WILL COMBINE WITH WARM MOIST AIR
ALOFT...TO SPREAD SHOWERS AND THUNDERSTORMS ACROSS EASTERN KANSAS AND
WESTERN AND CENTRAL MISSOURI THIS EVENING AND OVERNIGHT. THIS
ACTIVITY MAY PRODUCE WIDESPREAD RAINFALL OF UP TO ONE INCH FROM
SOUTHEAST KANSAS AND SOUTHWEST MISSOURI INTO CENTRAL AND NORTHEAST
MISSOURI BY DAYBREAK. WITH THIS RAIN OCCURRING ON TOP OF GROUND THAT
WILL STILL BE QUITE WET FROM EARLY RAINFALL...ADDITIONAL FLOODING
PROBLEMS WILL LIKELY OCCUR. A FLOOD WATCH IS IN EFFECT FOR ALL BUT
EXTREME NORTHWEST MISSOURI AND NORTHEAST KANSAS.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

SHOWERS AND THUNDERSTORMS WILL LIKELY BE ONGOING THURSDAY MORNING
CONTINUING THE FLOOD THREAT. BY EARLY AFTERNOON...SOME CLEARING MAY
BEGIN TO TAKE PLACE IN EASTERN KANSAS AND WESTERN MISSOURI. IF IT
DOES...THE INSTABILITY WOULD BE INCREASING TO RESULT IN STRONG TO
SEVERE THUNDERSTORMS. THE BETTER CHANCE OF SEVERE WEATHER WILL BE BY
LATER AFTERNOON INTO CENTRAL MISSOURI...WHERE THE INSTABILITY AND
SHEAR WOULD BE SUPPORTIVE OF HAIL...DAMAGING WINDS AND POSSIBLE A FEW
TORNADOES.

COLDER AIR WILL BE WRAPPING AROUND THE BACK SIDE OF THIS STORM SO
THAT ON FRIDAY...NORTHWEST MISSOURI AND NORTHEAST KANSAS MAY SEE RAIN
CHANGING OVER TO SNOW. DURING THE FRIDAY NIGHT TO SATURDAY
TIME FRAME...SNOW SHOWERS MAY OCCUR ACROSS NORTHEAST KANSAS AND THE
NORTHERN HALF OF MISSOURI. NO SIGNIFICANT ACCUMULATIONS OF SNOW ARE
EXPECTED.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION FOR REPORTS OF FLOODING MAY BE NEEDED WEDNESDAY
NIGHT AND THURSDAY. SPOTTER ACTIVATION FOR SEVERE WEATHER MAY BE
NEEDED THURSDAY AFTERNOON AND EARLY EVENING.

PC