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

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FXUS63 KEAX 062017

National Weather Service Kansas City/Pleasant Hill MO
317 PM CDT TUE OCT 6 2015

Issued at 317 PM CDT TUE OCT 6 2015

There are a few concerns in the short-term portion of the forecast.
One being fog potential tonight and the other being the
weather associated with the frontal passage Thursday/ Thursday

For tonight, high pressure is going to be situated right over the
region resulting in light/calm winds. Current dewpoints are in the
mid to upper 50s with overnight lows expected to be in the mid 50s.
So it looks like we`ll see several degrees below our crossover
temperatures for much of the forecast area. The monkey wrench in the
gears though is if and/or when the lower clouds move off or
dissipate. Short-range models vary quite a bit in handling the lower
level moisture which adds to the uncertainty. But given the ambient
boundary layer moisture and calm winds, feel there is at least a
chance for some fog so will go with some patchy mention late tonight
through an hour or two after sunrise.

The other challenge through the first few days of the forecast deals
with the frontal passage, its timing and precipitation chances as
well as how warm temperatures may get ahead of the front. Models are
in good agreement with the timing of the front, moving it through the
area from Thursday afternoon through Thursday evening. Strongly
veered winds ahead of the front, with likely deep mixing, suggest
many areas will be in the low to mid 80s. The GFS is a bit warmer,
mainly due to increased mixing depth, but takes the area into the
upper 80s. For now, low to mid 80s ahead of the front seem most
likely. The chances for severe, or even strong storms, ahead of the
front look very low. As mentioned earlier, winds will be strongly
veered, limiting convergence along the front. Deeper mixing may limit
instability and with the upper level shortwave trough passing to the
north, the strongest forcing is kept away from the area. None- the-
less, there is a modest amount of instability, likely in the 500 to
1000 J/kg range, so a few storms are possible during the frontal
passage. While the coverage of precipitation looks to be in the
scattered range, it looks like more widespread post-frontal showers
and isolated storms may develop as forcing from a trailing upper
shortwave influences the region. This more widespread development may
come later in the evening and possibly south of the I-70. So if there
happens to be any outdoor activities Thursday evening, they don`t
necessarily look like a washout, but may not be dry either,
especially later in the evening and further south of I-70.

For the extended portion of the forecast, much cooler conditions
will move into the region by Friday morning in the wake of the cold
front. But the cool high pressure area will quickly traverse the
area with southerly flow returning for Saturday. Thus, the 60 degree
highs will be short-lived as a return to more seasonal levels is
expected Saturday. Warmer than normal temperatures are expected
Sunday into Monday as warm advection persists. The forecast gets a
little more uncertain from there as it looks like we`ll see another
front move through. But the cooler air may lag behind until the
middle to later half of next week.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday Afternoon)
Issued at 1224 PM CDT TUE OCT 6 2015

MVFR stratus will likely linger through much of the afternoon and
early evening with calm, variable winds. By the overnight, the cloud
layer looks to lift to VFR with a pocket or two of scattered clouds
by Wednesday morning. Will keep a close watch on fog development
overnight. Models are indicating this possibility, though cloud cover
may limit widespread development. Will revisit this potential for the
00Z issuance.


.EAX Watches/Warnings/Advisories...


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