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

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FXUS63 KEAX 070529

1229 AM CDT Mon Jul 7 2014

.SHORT TERM...(This Evening through Tuesday Night)
Issued at 357 PM CDT SUN JUL 6 2014

Morning rain and scattered to broken cumulus clouds this afternoon
has helped keep temperatures at bay somewhat this afternoon as
temperatures are ranging from the mid 80s to around 90. Heat index
values are ranging from the upper 80s to near 100 degrees across
northwest MO. These values will still rise a degree or two this
afternoon before falling back this evening.

An upper level shortwave this evening will drop down across the
western Plains of Ontario into the northern Great Lakes. This will
help force a weak cold front into the area tonight. With the forcing
being weak and a cap in place there still remains some doubt as to
whether or not convection will develop. Models are split on this
front with the GFS and NAM showing the cap weakening enough for
widely scattered thunderstorms to develop. Meanwhile most of the
short-range hi-res model keep conditions dry. As such have continue
to advertise slight chance to low chance pops after midnight across
the northern and central portion of the CWA. If convection does
develop damaging winds and large hail will be possible. Otherwise,
lows across the area tonight should range from the upper 60s to mid

Monday, the cold front will wash out across the southern CWA and
winds will turn back to southwest by tomorrow afternoon helping
temperatures to warm back into the upper 80s to mid 90s. Heat index
values will be in the Late Monday afternoon/evening a stronger upper
level trough will dig from the northern Plains into the Upper
Midwest forcing a stronger cold front into the area. With dew points
in the low 70s and instability on the order of 3000-4000 J/Kg of
CAPE...thunderstorms capable of producing large hail and damaging
winds will be possible tomorrow night. A second round of storms or
uptick in evening storms will occur late tomorrow night as a 40-50kt
southwesterly LLJ develops, fueling storms along the boundary which
will be draped somewhere near the I-70 corridor. Severe potential
will continue into tomorrow night with damaging winds and large hail
continuing to be the main threats. There will also be the potential
for flooding/flash flooding with PWAT values between 1.75"-2.25". If
storms train/redevelop along the front Monday night flooding will
most likely occur especially given recent wet conditions.
Consequently, a flood watch was considered however, uncertainty of
the location of heaviest rainfall has precluded it at this time.

Showers and thunderstorms may linger into Tuesday morning before
high pressure build in for the afternoon hours and much more
pleasant conditions with highs in the low to mid 80s and
respectively lower humidity values. Better yet, the surface ridge
will move directly over the forecast area on Tuesday night allowing
lows to drop into the low to mid 60s making for comfortable sleeping

.LONG TERM...(Wednesday through Sunday)
Issued at 357 PM CDT SUN JUL 6 2014

The medium range period will be marked by a general upper trough
over the eastern U.S. with an initially flat western upper ridge
which is progged to amplify by next weekend. Good continuity in the
models leads to a moderate confidence in the forecast through
Friday. However, as the global models diverge on the strength of the
eastern U.S. trough and placement of faster flow there is a rather
broad range in forecast outcomes.

Mid-week surface high pressure over the Central Plains should
provide below average temperatures and relatively low humidity
levels Wednesday. A gradual increase in temperatures and humidity
will ensue as the high pressure moves off to the east and return
flow allows gulf moisture to return. Should see reasonably high
PoPs Thursday night into Friday as increasing isentropic ascent
combines with a shortwave trough dropping southeast from the SD/NE
area to generate elevated convection ahead of a retreating warm

Typical heat and humidity should overspread the region on Friday as
the warm front lifts northeast through the CWA. The weekend outlook
is not so certain but will likely see a continuation of the heat and
humidity, just unsure how much heat. The ECMWF is faster in building
the upper ridge over the Rockies with several convective feedback
signals and/or embedded shortwaves moving through the Central Plains
and Mid MO Valley. The GFS is a bit slower in this process. +


.AVIATION...(For the 06Z TAFS through 06Z Monday Night)
Issued at 1214 AM CDT MON JUL 7 2014

Weak frontal boundary making its way southward toward the terminals,
and will cause a few hours of light and variable winds as it remains
in vicinity of the terminals. Widespread thunderstorm activity will
be present at or near the terminals, likely after 00z. The best
chance for thunderstorm activity will remain north of Interstate 70,
so KSTJ will have the best chance of getting several hours of heavy
rain. The KC terminals will also likely see some rain, but the
overall magnitude of the storms near KC are a little uncertain.
Expect the storms to move in after 00z, and likely stick around
through at least 06z, if not a few hours longer.




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