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fxus63 kict 211000 
afdict

Area forecast discussion
National Weather Service Wichita Kansas
400 am CST Thu Nov 21 2019

Short term...(today through Friday night)
issued at 359 am CST Thu Nov 21 2019

Significant winter weather impacts are not expected over the next 48
hours, but it is still a system Worth noting with some important
considerations.

Early this morning, a cold front continues to push east across
eastern Kansas, accompanied by a narrow band of convection. Thus
far, convective wind gusts have remained in check, with no reports
over 50 mph. Given the 50-60 kt low level jet overhead, I still cannot rule
out an isolated strong gust, but the potential appears very limited.

Despite strong caa, the coldest air (ie. Sub-32) lags the cold front
by about 200 miles or so. As of 3 am, surface obs are just starting to
reveal some temps in the low 30s across northwest Kansas. The delayed
arrival of the freezing temperatures could factor into precipitation
type as the next system approaches, especially at the onset.

Southwest of the plains, a well-defined upper level slow is spinning
over The Four Corners region. A 100kt jet rounding the base of the
low will eventually translate northeast into the Southern Plains as
the upper low lifts into the Central Plains. The left exit region of
this jet will provide increasing large-scale forcing for ascent
across the region, especially tonight through Friday morning. After
that, jet dynamics seem to be a bit more nebulous through the day
Friday and into Friday night, with lift more driven by warm air advection and
low/mid level convergence beneath the upper low.

Overall, model guidance is fairly well clustered regarding the large-
scale forcing/sources of lift. The problem lies in the depth of
moisture and surface temps. While large-scale forcing should be more
than sufficient for precipitation, varying moisture depths
(especially as it relates to the snow-growth region), makes the
precip type more problematic and somewhat less certain. Model
guidance this morning appears to be focusing the coldest temps aloft
and deepest moisture across central Kansas and, for now, is where we
think the greatest risk of all snow will reside. Elsewhere, a cold
rain and, at times, a wintry mix, appears more plausible. Of note,
and this is especially the case across south-central KS, the precip
could end up more snow than rain should a deeper layer of moisture
be realized. So, while the focus for now is central Kansas, be
careful not to completely write off the potential further south
(especially along/west of the Kansas turnpike).

Recent warm weather, plus the anticipation of less-than-ideal
antecedent surface temps, will likely offset snow accumulations
some. This should be a wet, slushy snow, with accumulations
generally confined to grassy and elevated surfaces. For now, we are
thinking a dusting to 1" across the I-70 corridor, perhaps as far
south as Hutchinson, with little, if any, accumulations elsewhere.
The caveat here is that the amount of lift present could lead to a
period of moderate snow for parts of the area and we can't
completely rule out some isolated higher amounts should a sufficient
amount of moisture in the snow growth region coincide with the
stronger lift. This could also be augmented by some convective
elements which could act to cool/moisten the column quicker than
forecast. Where this occurs, snow intensity and amounts could be
locally higher. Again, we're not talking significant snowfall, but
heavier intensity at times and minor accumulations could certainly
cause at least some minor impacts. Given the minor impacts, at
worse, we'll plan to hold off on any winter weather headlines, and
let later shifts re-evaluate the potential.

Across southeast Kansas, those convective elements may lead to some
embedded thunder and moderate to heavy rain as precip moves in late
tonight. Cold air advection looks much more delayed in that area,
making the precip type mostly rain.

Martin

Long term...(saturday through wednesday)
issued at 359 am CST Thu Nov 21 2019

Looking beyond the next 48 hours, dry weather returns through the
weekend along with moderating temperatures. Regarding the system
next week, model guidance has trended towards a much more
progressive and less deep system. While impacts could still be felt
locally, recent guidance paints a less impactful period. Broad, SW
flow then looks to return as we head towards Thanksgiving. Should
this end up evolving this way, we could be looking at a mild period
through Thanksgiving, with at least some chance for precipitation
(maybe more towards the liquid variety).

Martin

&&

Aviation...(for the 06z tafs through 06z Thursday evening)
issued at 1112 PM CST Wed Nov 20 2019

A line of showers along a cold front will move eastward from
central across south central and southeast Kansas overnight.
Scattered showers and isolated thunderstorms can also be expected
ahead of the front. While IFR/MVFR cigs will prevail with periods
of MVFR vsbys in showers, conditions will improve Thursday morning
to VFR from west to east across the area. Gusty southwest winds
ahead of the front will shift from the north-northwest after the
frontal passage. A thickening altostratus cloud desk is expected
to develop over the area Thursday afternoon/evening.

Ked



&&

Preliminary point temps/pops...
Wichita-kict 50 30 39 26 / 0 50 40 0
Hutchinson 48 26 38 23 / 0 40 40 0
Newton 48 28 38 24 / 0 40 40 0
Eldorado 50 30 39 27 / 0 40 40 0
Winfield-kwld 53 33 41 27 / 10 60 40 0
Russell 45 27 37 23 / 0 40 50 0
Great Bend 45 27 36 23 / 0 50 50 0
Salina 47 28 38 24 / 0 30 50 0
McPherson 46 26 37 22 / 0 30 40 0
Coffeyville 61 35 42 28 / 60 70 40 10
Chanute 54 33 41 28 / 20 50 30 10
Iola 52 32 40 28 / 20 40 30 10
Parsons-kppf 59 34 41 28 / 40 60 40 10

&&

Ict watches/warnings/advisories...
none.
&&

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