Area Forecast Discussion
Issued by NWS North Platte, NE

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FXUS63 KLBF 031802

Area Forecast Discussion
National Weather Service North Platte NE
1202 PM CST Sat Dec 3 2016

Issued at 3 am CST Sat Dec 3 2016

H5 hand analysis from this evening continues to indicate a fairly
chaotic pattern across the lower 48 and Canada. A tandem of
shortwaves were noted across the western half of the CONUS
tonight. The first shortwave was located over central Wyoming and
a second stronger shortwave was located over southwestern Arizona.
High pressure was located over the eastern Pacific, off the coast
of central California. north of this high, a trough of low
pressure was located over British Columbia with 100 to 150 meter
falls noted across the west coast of Canada. East of this trough,
high pressure was located over northern Manitoba with a downstream
trough of low pressure located over Quebec. Water vapor imagery
overnight has a nice plume of pacific moisture streaming into
Texas, the southern plains and Ozarks. Radar imagery overnight has
a broad area of rain and snow showers across western Kansas into
western Oklahoma and the Texas panhandle. This area of
precipitation has moved to the north northeast over the past
couple of hours with most of the radar returns in north west
Kansas not reaching the ground. As of 3 AM CST, across western and
north central Nebraska, skies were mostly cloudy with temperatures
ranging from 24 at O`Neill to 32 at North Platte.


.SHORT TERM...(Today and tonight)
Issued at 3 am CST Sat Dec 3 2016

Over the next 24 hours, clouds,temperatures and the minute threat
for precipitation in far eastern portions of the forecast area are
the main forecast challenges. For today: The shortwave trough,
currently over eastern Wyoming, will eject east into the Nebraska
panhandle, then western sandhills by this afternoon. East of this
feature, moisture will continue to stream into south central and
eastern Nebraska from the southern plains. Current model trends
continue to lift this moisture and lift just off to the east of
the forecast area today, so a dry forecast will be retained. The
00z GFS and 00z NAM12 solutions did develop some very light
precipitation in the far northeastern forecast area later this
afternoon, however, given the dry airmass in place over northern
Nebraska, decided to leave this area dry for now since the qpf
forecast was only around a hundredth of an inch. As for highs
today, they will be coolest in the east as skies will be mainly
cloudy. In these areas highs will struggle to reach 40 degrees.
Highs will be in the lower to middle 40s in the western half of
the forecast area, where clearing is expected by afternoon. Skies
will clear off overnight as the shortwave trough pushes into far
eastern Nebraska and western Iowa. Light westerly winds, drier air
and clear skies will lead to lows in the teens tonight. Guidance
temps seemed reasonable given the wind setup tonight, and actually
cut lows in the Platte River valley given the light westerly
drainage winds tonight.

.LONG TERM...(Sunday through Friday)
Issued at am CST Sat Dec 3 2016

It`s going to be unseasonably warm Sunday as increasing zonal
flow aloft increases downslope warming into Monday. Temperatures
are going to peak on Monday into the 50s with temperatures to turn
downhill and downright cold Tuesday and bitter cold Wednesday and Thursday
as the arctic high center ridges southeast along the leeward side
of the Rockies into the high plains. How cold will it be midweek
is the forecast challenge as the combination of cold temperatures
and northwest winds combine to create below zero wind chill
values. Temperatures forecasts beyond Monday could be a category
too warm that could easily be adjusted down going forward.

The Arctic front will plunge well south Tuesday with snow fall
amounts to be limited until Wednesday when the next low develops
along the boundary backed to the west and moves southeast. The
Panhandle and southwest will see some light snow or flurries
develop Wednesday as the surface ridge builds east and the flow
turns upslope. Snow amounts still look on the light side with one
to two inches possible for the far southwest.

Temperatures will peak Monday then drop each day bottoming out
Wednesday with lows dropping to single digits to below zero across
the northwest sandhills Thursday morning. Temperatures will begin
to recover Friday into the 30s for daytime highs as the surface
ridge of high pressure moves east.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1134 AM CST Sat Dec 3 2016

An upper level trough continues to move east, with stratus
exiting the CWA. High clouds will be on the increase, however VFR
conditions expected over the next 24 hours. Breezy west southwest
winds will diminish in the evening to around 5 kts.




SHORT TERM...Buttler
AVIATION...Gomez is the U.S. government's official web portal to all federal, state and local government web resources and services.