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Area forecast discussion 
National Weather Service Topeka Kansas
314 PM CST Mon Jan 26 2015

Short term...(this evening through tuesday)
issued at 310 PM CST Monday Jan 26 2015

A deep upper level trough across the eastern US will amplify tonight
along the eastern Seaboard, providing the northeast US with several
hours of very heavy snowfall tonight through Wednesday.

This afternoon, temperatures have warmed into the mid to upper 60s
across the County Warning Area. West central Kansas has warmed into the lower 70s as
downslope warming across the Central High plains is advected
southeast across western and central Kansas.

As the eastern US trough amplifies, low-level cold air advection develop from the
upper Midwest across the Great Lakes states and southward across the
MS and Ohio River valleys. As a result of increase low-level cold air advection a
surface ridge will build southward across the MO River Valley. The
western edge of the sfc ridge will be across eastern Kansas Tuesday
morning and then will slide east int MO. Farther west a Lee side
surface trough will develop across eastern Colorado. Surface winds across
the County Warning Area Tuesday morning will be light from the northeast and east,
then gradually become southeasterly through the afternoon hours.
Southeast surface winds across the western counties of the County Warning Area may
increase to 15 miles per hour with gusts of 20 to 25 miles per hour possible during the
mid and late afternoon hours. Forecast soundings show the boundary
layer only mixing to about 950mb across the eastern half of the cwa,
therefore, I kept highs a bit cooler on Tuesday with mid 50s to to
around 60 degrees across northeast and east central Kansas. During the
afternoon hours there will be quite the gradient in temperatures at
850mb with 16 deg c 850 temps across north central Kansas and 7 deg c
850 temps in extreme northeast Kansas. Ottawa County may reach near 70
degrees with deeper mixing to 925mb.

Long term...(tuesday night through monday)
issued at 310 PM CST Monday Jan 26 2015

Progressive shortwave trough flattens ridge over central U.S. And
brings warm advection and mixing Tuesday night. This should keep
lows in the upper 30s to lower 40s. Very warm day expected again
for Wednesday with southwesterly low-level flow turning to westerly,
and highs mainly in the 60s. Cold advection then follows for
Wednesday night, but mixing and relatively mild Post-frontal airmass
will still keep lows in the 30s. Continued cold advection on
Thursday will make for a cooler day with highs in the 40s.

Surface high pressure ridge moves across the area Thursday night and
Friday with cooler temps, which will still be above the normals for
this time of year.

Medium range models then bring lift ahead of another system across
the area beginning Friday night and continuing through Saturday
night. Details on speed of system as well as potential phasing of
northern and southern stream troughs varies amongst the models, with
GFS runs typically faster, and Gem and European model (ecmwf) slower. Suffice to say
that chances for precip will increase from southwest to northeast
Friday night, with a decent chance of rain and snow on Saturday,
then changing over to all snow Saturday night. If European model (ecmwf) is closer
to reality with its slower forecast, precip could hang on into
Sunday morning. Precip type a little tricky as precip arrives with
warming so there could be a chance of snow, then turning to rain, or
a mix of rain and snow for Saturday, then turning back over to all
snow Saturday night. Amounts will be very dependent on how much of
the quantitative precipitation forecast falls as snow, but some accumulation would be expected.

Colder air behind this system will bring near normal temperatures
for Sunday and Monday.


Aviation...(for the 18z tafs through 18z Tuesday afternoon)
issued at 1128 am CST Monday Jan 26 2015

Expect VFR conditions for the next 24 hours. West-northwest surface
winds of 10 to 13 kts with gusts to 20 kts through the afternoon
will diminish by sunset to less than 5 kts.


Fire weather...
issued at 310 PM CST Monday Jan 26 2015

Deeper layer mixing will continue through the late afternoon hours.
High temperatures will reach the mid 60s to around 70 degrees.
Minimum rhs will range from the mid 20s across the southwest
counties into the mid 30s across the northeast and east central Kansas.
Northwest winds of 10 to 15 mph with gusts to 20 to 25 mph will
continue through 600 PM. The combination of wind gust around 20 mph,
dry fuels and lower rhs will cause a very high fire danger for the
remainder of this afternoon across much of north central and
northeast Kansas. East central Kansas will continue with a high fire
danger through the remainder of the afternoon.


Top watches/warnings/advisories...


Short term...gargan
long term...gdp
fire weather...gargan

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