Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service North Platte NE
1115 am CST Friday Feb 12 2016

issued at 320 am CST Friday Feb 12 2016

Arctic high pressure continues to build south from the Dakotas and
Minnesota into Nebraska. At 08z...the leading edge of the front was
analyzed from near Pine Ridge South Dakota through North Platte then
southeast across nctrl Kansas. A large area of stratus extends north and
east of the front. No indication yet of fog development in western
Nebraska. The rap and hrrr models both suggest development near the
western edge of the stratus along advancing cold front in the
western sandhills into southwest Nebraska this morning. Temperatures
ranging from 26 to 32 across western Nebraska...with colder teens
reported in eastern South Dakota.


Short term...(today and tonight)
issued at 320 am CST Friday Feb 12 2016

The main forecast concerns will be the backdoor cold front forecast
to push into the western Nebraska Panhandle and northeast Colorado
by late this afternoon and its effects on high temperatures across
western Nebraska today. Only minor adjustments to highs today. Near
38 in the southwestern tier of counties in closer proximity to the front.
Lower 20s in Boyd and northestern Holt County where temperatures will
actually hold steady through the day from this mornings lows.

For tonight...a warm front will begin to push east into western
Nebraska. With widespread stratus already in place...conditions will
be favorable for patchy freezing drizzle to begin developing due to
a lack of ice crystals introduced from aloft. The patchy freezing
drizzle forecast to begin late this evening mainly west of a line
from Gordon through North Platte...advancing further east to near
Valentine through Broken Bow by late tonight. Where some saturation
does exist up into the dendritic layer...a 20 to 30 percent chance
for light snow across the eastern two thirds of the forecast area.
There will be an area in between where freezing drizzle and light
snow may both occur...mainly across western Cherry County south
through the central sandhills into southwestern Nebraska. Since only
a small amount of freezing drizzle can impact travel...will continue
to highlight the potential for the light freezing drizzle tonight
into Saturday morning in a Special Weather Statement and the
hazardous weather outlook.

Long term...(saturday through thursday)
issued at 320 am CST Friday Feb 12 2016

12z Saturday and beyond. Saturday will be another transition day as
an elevated warm front lifts east across the sandhills.
However...outside of the eastern Panhandle and western
sandhills...all other locations will continue to see temperatures
below freezing. This will facilitate a continued mention
of freezing drizzle into the early afternoon as soundings
indicate saturation below the dgz where there/S weak Omega. Where
sufficient saturation is shown is across our northeastern zones
where light snow is forecast. The models only suggest a few
hundreths at most quantitative precipitation forecast...and with very weak lift seen...snow
accumulations should only amount to a few tenths at best.
Additional snow chances are possible across our far northern
zones Saturday evening into early Sunday as a fast moving middle-
level disturbance drops southeast across the Dakotas. The models
continue to indicate the best forcing and moisture north of the
border across the only a few tenths additional snow
accumulations are expected.

Warming temperatures are forecast for Sunday as 850 mb T/S are shown to
climb back above 0c for the entire County Warning Area. Highs in the 40s are
forecast. Sunday evening...the models depict a fast moving middle-
level disturbance dropping southeast across the High Plains
of Colorado into western Kansas. At this point...forcing is too
weak within the County Warning Area for precipitation...but the 00z models have
trended slightly east with the projected quantitative precipitation forecast. Will need to
monitor closely as at this point we have a dry forecast going.
Into early next week a gradual warming trend is forecast as
ridging builds east into the western rockies and a trough deepens
into the southeastern states. Northwest flow aloft will usher
another disturbance across the region late Monday into
Tuesday...but the models largely disagree in the location of the
best forcing...will keep the inherited dry forecast going for now.


Aviation...(for the 18z tafs through 18z Saturday afternoon)
issued at 1115 am CST Friday Feb 12 2016

As wind swings around to the southeast...the probability of ceiling
below 1000 feet will increase late this afternoon and into tonight.
In addition to the low ceilings...there is a risk of freezing
drizzle and low level icing after 03z west of an anw-bbw line. Light
snow showers are expected along and east of a vtn-lbf line.


Lbf watches/warnings/advisories...


short term...roberg
long term...Jacobs

National Weather Service Glossary of Abbreviations