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

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295
FXUS63 KEAX 081742
AFDEAX

AREA FORECAST DISCUSSION
National Weather Service Kansas City/Pleasant Hill MO
1142 AM CST MON FEB 8 2016

.DISCUSSION...
Issued at 340 AM CST MON FEB 8 2016

Main concern with this forecast issuance remains the potential for
snow squalls this morning as a robust upper low drops through the
region. Although moisture with this system has been limited, a layer
of saturation between ~4-8 kft has supported light snow across the
forecast area since late last evening, and will continue to do so
this morning as the upper system pulls very slowly to the east. Low
to midlevel instability has been more than sufficient to give a
convective character to the light snow throughout the region, and a
turbulent, windy boundary layer has reduced visibility in these snow
showers, the missing ingredient for impactful snow squalls thus far
has been moisture availability, especially in the lowest levels of
the atmosphere. Some top-down saturation has increased surface
dewpoints by several degrees and have likely modified the low-level
atmosphere from its observed state on the 00z KTOP sounding, however
most surface dewpoint depressions remain above 10 degrees F and snow
rates have not been heavy enough to significantly reduce visibility
or result in more than a trace snowfall accumulation.

Forecast soundings appear to indicate that while some boundary layer
moistening may continue to occur as a result of precipitation, and
the saturated layer may lower with time, midlevel cooling may not
keep up with the rate of low-level cold air advection and diurnal
cooling, and lapse rates above 2-3 kft will begin to increase over
the next several hours, reducing instability in the saturated/
dendritic layer, and possibly continuing to limit the potential for
even periodic moderate snow rates. Will continue to mention reduced
visibility and travel issues this morning as snow accumulation
should become more efficient at colder temperatures and very strong
winds will create visibility restrictions regardless of snow rate,
but the potential for impactful snow squalls looks a little lower
than in previous forecast issuances. As a result, do not feel that a
winter weather advisory is needed in our area, unless snow rates
start to increase dramatically over the next few hours. Winds are
still expected to increase shortly after sunrise, as the surface
pressure gradient tightens and stronger winds aloft on the back side
of the trough edge eastward, so will continue the wind advisory for
the same areas (all but the far eastern tier of the CWA) through
this evening.

Quieter but still chilly weather is anticipated for the rest of the
forecast period, due to north to northwest flow being continually
reinforced by upper-level low pressure surging southward through the
Great Lakes and eastern CONUS areas through the remainder of the
work week. Uncertainty in the pattern and thus temperature trends
begin by the end of the work week when the EC and GFS disagree on
how far east to trek another deep upper low, and thus how far west
the associated Canadian surface high will position. Regardless, a
warming trend and perhaps some very light precipitation looks
possible near the end of the forecast period, the only question will
be whether it begins Friday and continues into the weekend, or
begins early next week as the EC indicates. Have dampened down the
long-range highs to show the potential for at least slightly below-
normal temperatures this weekend, then allowed temperatures to
increase for the beginning of next work week as a result of the
discrepancies.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday Afternoon)
Issued at 1141 AM CST MON FEB 8 2016

Conditions will generally be VFR this afternoon with the scattered
flurries/ snow showers. But a heavier snow shower may locally drop
conditions to IFR for a brief time, less than half an hour or so.
Winds will continue to be strong from the northwest through early
this evening. The gustiness may diminish overnight but should develop
again soon after sunrise Tuesday. However, by that time winds won`t
be nearly as strong as they`ve been so far today. There may also be
an area of MVFR ceilings build south into the area tonight. By mid
morning tomorrow though, conditions will begin to clear out.

&&

.EAX Watches/Warnings/Advisories...
KS...Wind Advisory until 6 PM CST this evening for KSZ025-057-060-
     102>105.

MO...Wind Advisory until 6 PM CST this evening for MOZ001>006-011>015-
     020>024-028>032-037>039-043>045-053-054.

&&

$$

DISCUSSION...Laflin
AVIATION...CDB



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