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Area forecast discussion...corrected 
National Weather Service Hastings NE
641 am CST Sat Nov 28 2015

Short term...(today and tonight)
issued at 508 am CST Sat Nov 28 2015

Biggest issue will be determining precipitation types.

As the closed low continues to wobble over the Great
seems to be making a bit of headway to the east into The Rockies in
the short term and models seem to be consolidating on the eventual
characteristics of the low. Models indicate that isentropic lift
will increase today into the evening.

We might be able to get a little bit of freezing drizzle
today...especially south...but not looking for anything huge enough
to warrant an advisory. The WRF does indicate the potential for
some light quantitative precipitation forecast...but the hrrr is stingy with precipitation
today...for example. A dry punch to the dendritic growth layer
will keep any precipitation type to freezing drizzle today into this
evening. Although the NAM continues the dry layer...the GFS does
indicate that the dendritic growth layer will begin to saturate
overnight I did stick in a possibility of snow along
with freezing drizzle. Now the exception this evening will be in
our southeast...where the dendritic growth zone could saturate indicated by the I kept a freezing
drizzle/sleet potential in for this area as the warm layer will
generally be between zero and two degrees. I figure that I am
covered with the freezing rain if we happen to not be saturated in
the layer of potential dendrites and get freezing drizzle instead.
I do not want to get too carried away with including a lot of
precipitation types I will try to keep it simple. Not
looking for much precipitation at all for today/tonight. Went
closer to hires nmm east for highs and superblend for lows it appears to be doing okay for lows this morning (i
raised lows this morning compared to the previous forecast).

Long term...(sunday through friday)
issued at 640 am CST Sat Nov 28 2015

The biggest concerns for the long term periods will focus on an
advancing upper level low pressure system which will bring slight
chances for precipitation to the outlook area over the weekend...and
eventually another snow storm by early next week.

The large upper level system becomes elongated and positively tilted
by Sunday morning stretching from Nevada into Wyoming. At the
surface...moisture is surging northward ahead of the rotating
system. Although models debate just how far north the surface
moisture will go...went ahead and kept at least slight chances in
the forecast. Drier air in middle levels will indicate more of a
freezing drizzle event on Sunday should precipitation develop at

Sunday night into Monday...the main upper level low will eject
across the Central Plains bringing more abundant moisture and better
lift to the forecast area. Again soundings and cross sections reveal
a large amount of moisture at the surface and drier air in the middle
levels. Beginning Sunday night relative humidity values in the middle
levels will increase especially across western and northwestern
zones first before spreading eastward. Made an attempt to show this
slight transition by changing precipitation type from freezing
drizzle over to snow in the forecast as the night wears on. Snow
accumulations are also based on these precipitation types. When its
all said and done...this could be the largest snow amounts for the
majority of the forecast far this year. Current snow
totals are shaping up to be in the 3 to 6 inch range for the
majority of the area..with slightly lesser amounts across north
central Kansas. Of course...this is not for certain as there are
still many uncertainties to consider. Timing of the upper level low
as it ejects across the fast will the middle levels moisten
up to allow snowfall instead of freezing drizzle...and temperatures
Monday afternoon as they slowly rise to near freezing or possibly
warmer. All of this could drastically reduce snowfall amounts. As
for headlines with this event...after collaboration with
neighbors...decided to wait to issue headlines simply because of the
uncertainty through the weekend. Did not want to box future shifts
in with headlines for later time periods if freezing drizzle over
the weekend turns out to be a bigger deal.

Beyond Monday night the weather pattern turns fairly as high
pressure and ridging settle across the forecast area. In fact
temperatures the remainder of the week will likely rebound to highs
in the 30s to even 40 degrees at times. Of course...this too could
be subject to change based on resultant snow cover from the Monday


Aviation...(for the 12z kgri/kear tafs through 12z Sunday morning)
issued at 551 am CST Sat Nov 28 2015

Ceilings will eventually dip to MVFR this evening as isentropic
lift increases and the boundary layer continues to saturate. There
is a small chance of primarily some freezing drizzle...more so for
tonight...but chances are small enough to leave out of this


Gid watches/warnings/advisories...



Short term...heinlein
long term...saltzman

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