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

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FXUS63 KEAX 200525

1225 AM CDT Wed Aug 20 2014

Issued at 1223 AM CDT WED AUG 20 2014

Focus for the early morning hours will be across the nern half of the
CWA and especially the north central and northeastern counties. Deep
layer moisture convergence has set up within a nw-se oriented band
from north central NE into north central MO. This aligns well with
the best 310-315K theta-e gradient and isentropic ascent. A
moderately unstable airmass is expected to be lifted northeast into
this region with scattered convection likely to form by 09z.
Precipitable water values are forecast to be around 1.75 inches which
would support moderate rainfall amounts. Short range and Hi_res
models have been pretty consistent zeroing in on this region so feel
fairly comfortable raising PoPs over north central and northeast MO.


.SHORT TERM...(This Evening through Thursday Night)
Issued at 312 PM CDT TUE AUG 19 2014


Models continue to indicate a northwest to southeast area of rain
late tonight. This closely corresponds to an area of strong theta-e
convergence as the moist low-level jet noses into the area. This
should also be the transition area to the strong elevated mixed
layer which should then cap the area off through the mid to late
part of the week. Have maintained the chance PoPs but trimmed the
western edge of them to confine them to the northeastern half of the
forecast area. There may be a fair amount of instability for storms
to work with, possibly as much as 2000 J/kg, but shear looks marginal
to support storm organization. So there may be a few strong storms
develop with marginally severe hail and strong winds possible.
Precipitable water values will range in the 1.8 to 2.0 inch range so
localized heavy rain is also likely. This could pose a localized
flooding risk, especially over areas that have seen heavy rainfall in
the last few days to week.

Wednesday - Thursday:

Warmer air aloft will move over the region which should inhibit
convective chances across the area. But this will lead to very warm
and humid conditions with highs in the mid to upper 90s likely by
Thursday. Thursday may get off to a very warm start as it looks like
the area will remain well mixed overnight, keeping low temperatures
in the upper 70s to around 80 degrees in the urban core of Kansas
City. As temperatures aloft warm into the 22C to 26C range during the
day at 850mb, surface temperatures will climb into the mid to upper
90s. With dewpoints in the low 70s resulting in high humidity around
peak heating, heat indices will range from 100 to 105 across the
area. So Thursday is looking like an oppressive day with the heat and

.LONG TERM...(Friday through Tuesday)
Issued at 312 PM CDT TUE AUG 19 2014

Warm and continued humid conditions expected early on in the period
as amplified upper ridging remains in place over the area. With
850-hPa temps still ranging in the low-mid 20C range...expect high
temps to once again climb into the lower to middle 90s across much of
the area on Saturday. Fcst becomes a bit more clouded by the latter
stages of the weekend as persistent upper ridge across the lwr/mid-
Miss Rvr Vly begins to shift east in advance of northern Rockies
upper-level low. As this occurs...models advertise the arrival of a
cold front but questions still remain as guidance continues to
disagree on frontal timing. The Canadian GEM advertises its arrival
as early as Sunday...while the GFS and ECMWF suggest the feature will
hold off for at least another 24-hrs with precip chances increasing
Sunday night into Monday. For now...have elected to offer a middle of
the road solution which brings initial chc for convection into the
area Saturday night thanks to a strengthening low-level jet...with
additional chances again increasing Sunday night into Monday. In any
event...southward sagging front should finally allow some cooler air
into the area early next week as clouds and precip remain on the
docket as front stalls over/near the region.


.AVIATION...(For the 06Z TAFS through 06Z Wednesday Night)
Issued at 1223 AM CDT WED AUG 20 2014

Will continue with a VFR forecast at all 3 terminals. A weak
stationary front lies across northern MO which is expected to drift
northward by sunrise. Scattered convection expected to form during
the pre-dawn hours from eastern NE through north central and
northeast MO...and remain northeast of the terminals. Sharp low-level
inversion present around 1500ft agl with marginal LLWS possible. Not
enough confidence of stronger winds being present to support adding
LLWS to forecast. Will continue to monitor radar VWP winds. Should
see an increase in southerly winds Wednesday afternoon with some
gusts around 20kts.




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