Area Forecast Discussion
Issued by NWS Kansas City/Pleasant Hill, MO

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

FXUS63 KEAX 250937

Area Forecast Discussion
National Weather Service Kansas City/Pleasant Hill MO
437 AM CDT THU AUG 25 2016

Issued at 437 AM CDT THU AUG 25 2016

It`s looking a bit wet for the next several days across the Lower
Missouri River Valley as the broader pattern across the Nation keeps
the potential for thunderstorms persisting through the weekend in
our section of the country. Big picture; water vapor imagery shows
the Nation dominated by a bit of an amplified pattern with a trough
extending from the Hudson Bay southwest across the Western United
States and a ridge spinning over the Deep South, along the Gulf
Coast. The trough that moved across Canada, into the Hudson Bay,
dragged a cold front through our section of the Plains States
Wednesday, but the front stalled across the northern half of
Missouri early this morning as it became increasingly parallel to
the flow aloft and current looks to reside along a line from
north Kansas City to Kirksville.

The frontal boundary in northern Missouri will likely wallow there
through the day as the main shear axis of the parent trough
continues to stretch across the Plains. This will allow the Gulf
Coast ridge to keep pumping moisture from the western Gulf north,
combining with the moisture plume emanating from the eastern Pacific
across northern Mexico. The local implication being that any little
eddy that rides the leading edge of the shear axis northeast will
likely result in thunderstorms today, tonight and Friday in areas
near the stalled front, which will be eastern Kansas and much of
northern Missouri. As a result, expectations are that there will be
few rounds of storms that will track east-northeast today, Friday and
into Saturday.

Activity currently across eastern Kansas and Missouri early this
morning will continue to shift east-northeast with a little break in
the rain activity expected before another complex of storms
--currently in central Kansas-- moves through during the day, likely
along a path a little north of the current early morning activity.
While these storms will continue to be efficient rainmakers, will
drop the Flash Flood Watch early this morning as the upstream
activity does not look like it will result in flooding before the
expiration time of the watch, and confidence on issuing a new watch
box is low owing to the repeated breaks that will occur between the
different rounds of rain. But, there will be a bit of a severe
threat in areas along and south of the Missouri River later today
and tonight as this region will --in general-- be in the warm sector
ahead of the stalled front, with CAPE values of 3000+ J/KG by this
afternoon advertised to be under the rear inflow region of the 300mb
jet and 0-6KM shear values of 40 to 50 knots. However with the flow
aloft parallel to the front, thoughts are that damaging winds and
hail will be the main threats again later this afternoon and this
evening along with torrential rain.

Focus for storms is expected to then shift more into eastern
Nebraska as we move into Friday as the stalled front should lift
back to the north as a following trough moves through the Rockies.
This will likely result in the focus for more storms moving back into
areas north of the Missouri River, likely near the Iowa border Friday
night into Saturday as another complex of storms moves east.
Potential for more flooding and severe weather is hard to discern at
this time as it will depend on what occurs today and tonight.

Looking beyond Saturday in general...the trough moving through the
Rockies Friday will help flatten the flow across the Nation over the
later half of the weekend into next work week, and while that will
take some of the focus for storms off the Central Plains, the threat
for storms wont completely disappear as the Gulf Coast ridge
continues to pump moisture north from the Gulf, and the shear axis
from the Rockies trough looks to wallow in our vicinity of the Plains
into next week.


.Aviation...(For the 06Z TAFS through 06Z Thursday Night)
Issued at 1205 AM CDT THU AUG 25 2016

The bulk of the heavier showers and storms will affect mainly
northeast into central MO through the pre-dawn hours of Thursday
morning. Scattered convection with VFR ceilings will persist through
the rest of the night into mid Thursday morning. Should also see
Ceilings lower to MVFR over east central KS into northwest and west
central MO by the pre-dawn hours. Should see these ceilings rise to
VFR by late morning and remain VFR through the afternoon.

Much uncertainty exists as to the evolution of late afternoon and
evening convection due to existing boundaries left over from
overnight convection. However, best bet for seeing convection appears
to be Thursday evening.


.EAX Watches/Warnings/Advisories...


Aviation...MJ is the U.S. government's official web portal to all federal, state and local government web resources and services.