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fxus63 kgid 200829 

Area forecast discussion
National Weather Service Hastings NE
329 am CDT Fri Sep 20 2019

Short term...(today through Saturday night)
issued at 328 am CDT Fri Sep 20 2019

Early this morning, overall things are quiet across the cwa, with
some scattered shower/thunderstorm activity still ongoing across
western portions of NE/KS. Upper air and satellite data show
south- southwesterly flow is in place across the region, set up
between ridging extending from the Gulf Coast region northward to
the Great Lakes and low pressure spinning over the Utah/Idaho region.
At the surface, winds remain south-southeasterly as a trough of
low pressure extends along the High Plains and higher pressure
dominates much of the eastern Continental U.S..

Confidence in the forecast for today isn't the highest, especially
with preciptiation chances. Models are in good agreement not
showing a significant change in the southwesterly flow aloft, with
the main upper low sliding east into the Montana/Wyoming region. While
models aren't showing much in the way of a lifting mechanism
moving through the region, they continue to hint at the potential
for at least isolated precip around through the day. It's
difficult to pin down specific areas that have better chances than
others, so forecast is Liberal with the low chances pops through
the day. The better axis of instability/shear looks to focus just
off to the west of the cwa, and that is where the Storm Prediction Center day 1
marginal/slight risks are centered...but can't totally rule out a
strong storm this afternoon/evening across western portions of the
County Warning Area.

As we get further into tonight, and especially into
tomorrow/tomorrow night, storm chances look to increase. Tonight,
models show the corridor of a 40-ish kt low level jet extending north
through the area...and while the better focus along its edges
looks to be north and east of the County Warning Area...can't rule out some at
least scattered activity, but kept pops low. During the day on
Saturday, the main sfc cold front accompanying the upper low (now
working into the western dakotas), will start pushing south
through the County Warning Area...providing a focus for thunderstorms, especially
during the afternoon/evening hours. At this point, models are in
pretty good agreement that by the time we are getting to that
timeframe with better potential for thunderstorms (and severe
weather), that frontal boundary will be across far south-
southeastern portions of the County Warning Area...if not just outside the County Warning Area
boundary. Still some uncertainty with the exact timing of that
front pushing south. So until that front can push south of the
cwa, instability/shear parameters and good lift keep the concern
for severe weather around, and portions of the County Warning Area are included in
the day 2 Storm Prediction Center slight risk. The nbm kept some fairly high pops
into the overnight hours Sat night, but wouldn't be surprised to
see those trended down, as the front/lift pushes south the better
precip chances should as well.

Didn't make any notable change to the forecast highs for today,
which look to be cooler than yesterday, in the mid 80s. Highs for
Saturday are tricky with a daytime frontal passage...locations
south of the front may mix out more and have warmer temps.
Currently have upper 70s in the northwest to mid 80s in the
southeast...but the timing of the frontal passage will be play a
big part in that.

Long term...(sunday through thursday)
issued at 328 am CDT Fri Sep 20 2019

There may be a bit of lingering activity across eastern portions
of the County Warning Area Sunday morning, but for the most part things will be
winding down (if they haven't already). During the first half of
the day on Sunday, models are in good agreement showing the main
upper level trough continuing to swing through the
central/northern plains, and by evening should be moving east of
the MO river. Dry conditions are forecast to continue on into
Sunday night and at least the daytime hours on Monday, thanks to
shortwave upper level ridging set up between the departing system
and another digging south through the western Continental U.S.. expecting to
see plenty of sun for Sunday, increasing upper level clouds as we
get into Monday.

At the surface, winds are expected to be fairly light on Sunday,
with higher pressure settled over the area in the wake of the
frontal passage. Later in the day and into Sunday night, there
looks to be a period of light/variable winds, before turning
southerly through Monday, as the high slides east of the County Warning Area and a
trough of low pressure develops over the High Plains. This sfc
cold front isn't overly strong, and while temps will be cooler for
Sunday, it isn't a significant drop. Highs for Sunday are
forecast to reach the mid 70s for the majority of the
County Warning Area...climbing back into the lower- mid 80s for Monday.

Precipitation chances return to the forecast for Monday night and
into Tuesday, but confidence is not high. Models show more
southwesterly flow develops in the upper levels, thanks to a low
pressure system moving into The Four Corners region. The GFS is
more aggressive with the onset of any precip chances, already
bringing a shortwave disturbance through the region out ahead of
the main low Monday night...the European model (ecmwf) is slower, and keeps much of
the area dry through Tuesday. Upper level flow is expected to
turn more zonal for the middle of the work week, with the main low
pressure system looking to slide east into the Texas/OK Panhandle
area...before potentially taking a more northeastward trek through
the end of the week. The forecast currently has Wednesday dry,
with pops returning thurs-Fri, but it's difficult to have a lot of
confidence in the exact details of the track/timing this far out.

As far as temperatures go Tuesday through Friday, not looking to
see any notable swings either way. Forecast highs remain in the
mid 70 to mid 80 degree range.


Aviation...(for the 06z kgri/kear tafs through 06z saturday)
issued at 1209 am CDT Fri Sep 20 2019

Have VFR conditions in the forecast for this taf period, though
confidence in that during the final 3-6 hrs is not high with some
models showing low level stratus developing. Precipitation chances
during the period are not zero...but confidence in exactly where
things may develop is not high, and models suggest it may be
pretty scattered in nature, so do not have even a vc mention at
this point. Winds are expected to remain south-southeasterly
through the period, increasing after sunrise. Gusts around 30 miles per hour
are expected during the daytime hours, with little improvement
even into the evening hours.


Gid watches/warnings/advisories...

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