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

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FXUS63 KEAX 251720
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1220 PM CDT Tue Jun 25 2019

.Discussion...
Issued at 343 AM CDT TUE JUN 25 2019

Today looks to be the last real active day storm wise for the next
week. The overall upper level flow is rather zonal with a few minor
shortwave troughs embedded along the west to east flow. One of these
troughs is currently moving through the northern plains now and is
helping to enhance a weak storm complex over eastern NE which may
effect northern Missouri later this morning. On the surface there is
troughing over the northern plains near the Great Lakes with high
pressure and ridging over the southern Mississippi River Valley.
This setup will help to create a quasi-stationary boundary over
northern Missouri as they interact with each other providing the
main focus for convection this afternoon. A LLJ moving through
eastern Kansas this morning will help bring WAA over northern
Missouri with a push of higher dewpoints at the surface as well. This
combination of higher temperatures and dewpoints will allow MLCAPE
values to rise to near 4000 J/kg in the late afternoon as the weak
capping inversion is stretched and eventually broken. Combining this
potential instability with a trigger and 0-6km bulk shear of 40kts
will lead to a higher likelihood of severe weather. Storm mode will
be a an evolving process today as hodographs show an
anticyclonically curved hodograph (mostly above 1km) which would
indicate possible supercells at convective initiation. Surface to
1km SRH remains below 100 with veered surface winds so the tornado
threat is low, but not zero. 700-500mb lapse rates between 8-9C/km
and potential rotating updrafts would lean the main threat to be
large hail, isolated greater than 2", and possible damaging winds
with DCAPE values near 1200 J/kg. Mean storm motion along the
boundary will cause the storms to quickly shift to a linear storm
mode and possible training storms. Since this area has gotten to
much rainfall in the last week the 1 hour flash flood guidance is
around 1.75". It is possible this could occur locally in a county or
two north of HWY 36 and will need to be monitored once storms
develop. The surface boundary does not appear to move much going
into the evening so storms may remain anchored in that area with
little southerly movement until cool pool generation occurs. The
HRRR and RAP don`t have much of a southerly shift with these storms,
but if the cold pool gets going the backwards trajectory Corfidi
vectors do show a SE motion. I would expected the latest NAMnest
solution to be more accurate with a shift into central Missouri and
possibly the KC Metro if things in NE KS can get going. There will
be plenty of MUCAPE available, but luckily the LLJ will remain weak
and not provide any extra convergence and energy to the MCS if it
surges south. A developing LLJ over central KS may be enough to
develop elevated convection and another round of storms pushing
through early Wednesday morning, but uncertainty is high with the
evolution of the first line of storms being difficult to predict.

Upper level ridging will FINALLY move into our area starting
Wednesday and effectively turn off the faucet we have been under for
weeks. While this will help dry out the area it will finally bring
more summer like temperatures to our area to end the week and into
the weekend. High temperatures will get into the upper 80s Wed and
Thur with heat indices in the mid to upper 90s. The furnace will
really start cranking going into the weekend as the upper level
ridge moves overhead with a steady stream of Gulf moisture going
into our area. Temps Friday into this weekend will climb into the
lower to id 90s with dewpoints in the 70s. This will shoot our heat
indices into the upper 90s to lower 100s for multiple days for the
first time. Since people are not acclimated to this kind of heat
just yet there could be issues with heat related illnesses and
people need to start hydrating before we get to the weekend to help
prepare for our first real heat of the year.

&&

.Aviation...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1220 PM CDT TUE JUN 25 2019

A weak boundary is moving into southern NE and IA currently and
should settle into the four-state border area by this afternoon.
This boundary will be the focus for afternoon and evening storms.
The evolution of these storms is uncertain but confidence remains
low enough to not carry anything but VCTS through the terminals
this evening. It seems more likely that after storms develop along
the boundary, they`ll track to the ESE across northern MO, not
necessarily through the terminals. Given this, have kept
conditions VFR at the terminals with some diurnal CU this
afternoon through tonight.

&&

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

$$

Discussion...Barham
Aviation...CDB



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