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Area forecast discussion 
National Weather Service Kansas City/Pleasant Hill MO
645 PM CDT Tue Aug 19 2014

Short term...(this evening through Thursday night)
issued at 312 PM CDT Tuesday 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 Tuesday 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 European model (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 00z tafs through 00z Wednesday evening)
issued at 639 PM CDT Tuesday Aug 19 2014

Should see VFR conditions through the forecast.

Weak frontal boundary across northern MO likely to focus any
convection over this area and away from the terminals overnight.
Model soundings develop a strong low-level inversion overnight with
marginal low level wind shear conditions between 06z-13z. Will leave out of the
forecast but monitor this evening. Strong mixing Wednesday afternoon
should produce winds in excess of 12kts.


Eax watches/warnings/advisories...


Short term...cdb
long term...32

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