Forecast Discussions mentioning any of "ACARS" "MDCRS" "AIRCRAFT" "TAMDAR" "AMDAR" "WVSS" received at GSD on 04/13/19

Area Forecast Discussion

National Weather Service Hastings NE

 652 PM CDT Fri Apr 12 2019

.SHORT TERM...(This evening through Saturday)
Issued at 326 PM CDT Fri Apr 12 2019

Aloft: A longwave trof extended from MT-AZ with ridges along the
E and W coasts...per RAP dynamic tropopause analyses and aircraft
obs. The low that affected the rgn Thu was lifting out of the mean
trof to LkSup. A shrtwv trof was at its base just S of AZ/NM.
Cyclonic WNW flow over NEB/KS back to SW and become anticyclonic
tonight into tomorrow...as the LkSup low heads into Canada and the
shrtwv trof moves out of MX into TX and strengthens. Meanwhile...
the Wrn longwave trof will move E to the High Plns by 00Z/Sun.

Surface: The influence of the cyclonic flow lingering over the
rgn was dcrsg with a strip of wk high pres building in.
Anticyclogenesis will occur over NEB tonight...with the high
strengthening overhead. This high will drift N into SD tomorrow as
strong low pres moves acrs TX.

Rest of this afternoon: Chilly with NW winds gusting 30-40 mph
pushing WCI`s into the upr 20s at times.

Plenty of stratocu in the linger cold air...espcly N of Hwy 6.
Cld depths will be aprchg their peak and some of the most robust
stratocu could produce some sprinkles/ flurries.

Diurnal clds will rapidly dissipate in the 1-2 hrs prior to
sunset.

Tonight: Winds will drop off early. Mstly clr to start...but
probably turning p/cldy S of Hwy 6 as mdl X-sections show some
potential for mid-lvl clds. They`ve been on satellite all day
over Wrn KS/Ern CO.

Cold with lows in the 20s.

Sat: Becoming mstly cldy as a large shield of cirrostratus moves
into the area from the TX system. Warmer than today but still 10F
cooler than normal.

.LONG TERM...(Saturday night through Friday)
Issued at 326 PM CDT Fri Apr 12 2019

Aloft: The flow will temporarily deamplify. A low-amplitude
shrtwv rdg will move thru Sun with zonal flow Mon. A strong shrtwv
trof will move onshore in the W Mon night. The flow will amplify
as it moves inland and digs...with winds backing to SW here on the
Cntrl Plns. This trof will move thru Wed. Mdls are fcstg lee
cyclogenesis. The 500 mb low is fcst SW-NE acrs KS. Highly-
amplified NNW flow will linger into Thu-Fri.

Surface: High pres will drift E of the rgn Sun while low pres
forms over AB with a cool front advancing thru the Wrn USA.
Downslope warming will induce warm frontogenesis from ND-TX. This
warm front will lift acrs the CWA Mon while the wk cool front
advances into Nrn Plns. The cool front will move thru Mon night
and become stationary acrs KS Tue...anchored by a new lee low fcst
to form over CO. This low is fcst to eject acrs KS/NEB Tue night
into Wed...but there is considerable spread among the last 2 runs
of global mdls on location /timing. This has important
implications for how far the warm sector lifts N...instability/svr
wx...and dare I say snow potential Wed night. See below. The rgn
will be in the cold sector Thu as low pres departs to the NE. High
pres should build in Fri.

Temps: Inching back close to normal Sun...but trimmed temps NW
1/3 for remaining snow cover. Warmer than normal Mon-Tue by about
10F. Wed very uncertain. It could be incredibly cool (highs in the
40s) if the warm front and low remain S of the CWA...or some 70s
could occur over the SE 1/2. Thu-Fri cooler than normal.

Precip: There could be some sprinkles along and N of I-80 Sun
night. Probs are not high enough to include in the fcst...but we
may need to add them when this period gets into the short-term.
Some more sprinkles could also occur N of I-80 Mon night as well.
Then we await the system for Tue night-Wed night. The lack of
consensus on the storm track precludes providing any details. We
will be watching potential for svr tstms ahead of the system and
possibly some wraparound snow as temps cool Wed night. There will
be potential for high winds as well.

&&

.AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Saturday)
Issued at 625 PM CDT Fri Apr 12 2019

VFR conditions are expected to continue throughout the TAF valid
period. The wind will die down this evening and could become light
and variable at times Saturday morning before eventually becoming
northerly by late morning.

&&

.GID WATCHES/WARNINGS/ADVISORIES...
NE...None.
KS...None.
&&

$$

SHORT TERM...Kelley
LONG TERM...Kelley
AVIATION...Wesely