Flash Flood Warning 56, NWS Kansas City, MO

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
410 AM CDT Wed Aug 21 2019

.Discussion...
Issued at 410 AM CDT WED AUG 21 2019

Satellite imagery shows a northwest flow developing across the
northern and central Plains early this morning in response to a
trough that is shifting into the northern Plains States, where it
will sweep across the Great Lakes in the coming days. And, it is
this trough that will be primarily responsible for the nice
weather (afternoon highs in the 70s to low 80s) expected to
prevail for the tail end of the work week and the coming weekend
as it sweeps a seasonally cool surface high sweeps into the
region. But, first we will have to deal with a couple days of
stormy weather.

Looking across the Plains, a lee side surface low has developed
across the front range of the Rockies in response to the cool
surface high the northern Plains trough is ushering into the
States. This has resulted in a frontal boundary stretched from
west central Kansas through southeast Nebraska into central Iowa
early this morning, which a diffluent nocturnal jet has developed
along, inducing strong warm air and moisture advection across
northern Kansas and southern Nebraska, where precipitable water
values of 2.1 inches has pooled. All this, in turn, has sparked a
line of strong to severe thunderstorms across central Nebraska
southeast into extreme northeast Kansas and far northwest
Missouri, which will be of concern well into the morning, and will
perhaps set the stage for more storms later today.

Storms in northeast Kansas and northwest Missouri will continue to
percolate along through sunrise as the low level jet keeps feeding
warm, moist air into the storms from the southwest. These storms
will be rather strong, but pulsy, as there is lots of instability to
work with (MUCAPE values > 4000 J/KG) but hardly any shear. This
will make large hail and damaging winds possible with these morning
storms, but will also bring a threat of flash flooding as the storms
look to train over the same locations of northeast Kansas and
northwest Missouri during the morning hours. There is some
expectation that the storms will spread east across far northern
Missouri this morning, which could lay out an effective boundary
from the rain induced cold pool for the afternoon hours. Models key
a bit on this cold pool as the shortwave trough swings through the
northern Plains to generate more scattered storms through the
afternoon hours. Confidence in the development of the afternoon
storms is a bit low, but can not ruled out, so have kept likely
POPs going for now.

Tonight into Thursday the cool surface high across the northern
Plains will slide farther south, and with it the frontal boundary
along its leading edge. This will move the focus for storms south
late this afternoon and through the overnight hours, with any late
night storms likely being rather strong, as there will be plenty of
instability aloft to work with.  Additionally, flash flooding may be
a concern given that precipitable water values pooled along the
boundary will be just over 2 inches. And, while we do expect the
activity late tonight to slowly settle south, it will do so slowly
enough to leave storms likely from eastern Kansas across central and
southern Missouri into Thursday afternoon.

Thursday on into the weekend...will see lovely temperatures in the
70s to low 80s prevail as a cool surface high slides across the
region. This will also move the focus for storms into Southern
Missouri for Thursday and Friday nights. Can't rule out any more
storms thanks to the nocturnal jet and abundant moisture in place
across the Plains States, but for now much of the weekend looks dry
across our section of Kansas and Missouri.

&&

.Aviation...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1208 AM CDT WED AUG 21 2019

Several rounds of scattered thunderstorms are expected over the
next 24 hours. Tough to find periods where chances for rain are
low, but once showers pick up in the next 2 to 4 hours most of the
remaining period will have increasing chances for rain. Not
expecting continuous rain at the terminals, but off and on showers
will likely prevail through Wednesday evening. Could see wholesale
decreasing chances for rain toward the end of this forecast period
for Wednesday night.

&&

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

Discussion...Cutter
Aviation...Leighton

Hazardous Weather Outlook
National Weather Service Kansas City/Pleasant Hill MO
524 AM CDT Tue Aug 20 2019

KSZ025-057-060-102>105-MOZ001>008-011>017-020>025-028>033-037>040-
043>046-053-054-211030-
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-
524 AM CDT Tue Aug 20 2019

This hazardous weather outlook is for northwest...north central and
west central Missouri...as well as extreme eastern Kansas.

.DAY ONE...Today and Tonight

Very hot and humid conditions are expected this afternoon, with
dangerous heat indices developing.

Thunderstorms are expected this morning across northeast Missouri, a
few may be severe with strong winds.

 More detailed information can be accessed at...
 https://www.weather.gov/eax/hwo

.DAYS TWO THROUGH SEVEN...Wednesday through Monday

Periodic chances for thunderstorms will continue Wednesday morning
through Thursday. A few of these storms may be strong to occasionally
severe.

 More detailed information can be accessed at...
 https://www.weather.gov/eax/hwo

Special Weather Statement
National Weather Service Kansas City/Pleasant Hill MO
351 AM CDT Wed Aug 21 2019

KSZ102-MOZ020-210915-
Doniphan KS-Buchanan MO-
351 AM CDT Wed Aug 21 2019

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN DONIPHAN AND
NORTHEASTERN BUCHANAN COUNTIES UNTIL 415 AM CDT...

At 349 AM CDT, Doppler radar was tracking a strong thunderstorm over
Elwood, moving east at 30 mph.

Winds in excess of 45 mph will be possible with this storm.

Locations impacted include...
St. Joseph, Gower, Wathena, Elwood, Agency, Easton and St. Joseph
Airport.

This includes the following highways...
 Interstate 29 between mile markers 38 and 50.
 Interstate 229 between mile markers 0 and 8.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Torrential rainfall is also occurring with this storm, and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

&&

LAT...LON 3964 9498 3980 9497 3982 9460 3962 9460
TIME...MOT...LOC 0849Z 258DEG 25KT 3972 9487

Blair