Scientific Forecaster Discussion
fxus63 kgid 222354
Area forecast discussion
National Weather Service Hastings NE
554 PM CST Fri Nov 22 2019
Short term...(this evening through saturday)
issued at 250 PM CST Fri Nov 22 2019
Snow ends this evening...then dry/mild for the weekend
An upper low pressure system crossing through Kansas has produced a
swath of snow which has impacted our southern zones today. The
higher snowfall amounts of 1-4" have been confined to primarily
Rooks-Osborne-Mitchell counties. There has been a fairly sharp
gradient of areas of snow vs no snow from south to north...where
drier air is place in neb under the influence of a sfc ridge. The
snow will be ending in the next few hours as the upper low pressure
system departs into eastern Kansas. Light winds and a gradual
decrease in cloud cover is expected through the night. Have
included the potential for patchy fog for locations with recent
snow cover...but confidence is not high.
Heights rise behind the departing system tonight/Saturday, with
warm air advecting east onto the plains. Afternoon temps will be
noticeably warmer than the last couple days with highs mainly
50-55f. The warmer temps will be accompanied by increasing
northwest winds in the afternoon with gusts of 25 mph.
Long term...(saturday night through friday)
issued at 250 PM CST Fri Nov 22 2019
The remainder of the weekend will round out with dry conditions and
some really nice weather on Sunday. Winds are looking to be
relatively light from the west and temps have trended up aided by
the downslope wind component with highs around 60 degrees. Then, a
cold frontal passage Sunday night will cool temps down for
Monday...returning highs closer to the 50 degree mark.
The weather pattern becomes more active Tuesday and remains
unsettled next week and into the Thanksgiving Holiday weekend. An
upper low pressure system crossing our region Tuesday will bring
increasing chances for rain/snow beginning as early as Monday night
and lasting through the day Tuesday. The extended models are in
agreement that this system will bring some precip to our area, but
there remains uncertainty in the track and strength of the system.
Our current forecast has snow chances during the early morning
Tuesday with the precipitation transitioning to rain during the day.
Model thermal profiles suggest precip type could favor more of a
a wet snow with a few inches of accumulation possible. Have not
deviated from model ensembles attm, but this will be a period to
watch for any pre-Thanksgiving activities/travel.
Dry weather is expected in between systems Tuesday night through
Wednesday, then precip chances may return as early as Wednesday
night as flow aloft transitions southwest ahead of a potent closed
low/upper trough off the coast of northern California. Intermittent chances
for precip exist off/on next week ahead of the western trough...
and the weekend following the Thanksgiving Holiday could be active
as the western trough reaches the plains. Forecasts details will
be refined with time, so be sure to stay up to date on the latest
forecasts in this unsettled pattern.
Aviation...(for the 00z kgri/kear tafs through 00z saturday)
issued at 552 PM CST Fri Nov 22 2019
Significant wx: watching potential for fog overnight
Tonight: VFR. The northern edge of light snow and MVFR cigs should
remain just S of the terminals over the next few hrs, with mainly
4-6k ft cigs expected. Low to mid clds will scatter out by
midnight, but the clearing may allow for some fog development
after 07z. Models are mixed on this, but generally keep the
greatest fog development just S of the terminals. Have introduced
some 6sm br for now, but confidence in this aspect of the forecast
is low. May need to go lower with next forecast, but will
monitor short term model trends.
Saturday: VFR. If fog develops, should decr 13-15z as winds incr
and veer from SW to northwest. Winds will bec breezy by midday, with
sustained winds 12-15kt with gusts around 25kt. Confidence: medium