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Area forecast discussion 
National Weather Service North Platte NE
302 am CST Monday Feb 8 2016

Synopsis...
issued at 302 am CST Monday Feb 8 2016

At 500 mb strong western Continental U.S. Ridge and deep eastern Continental U.S.
Ridge with closed low over the Great Lakes. Seve4ral strong waves
over the eastern Pacific.

&&

Short term...(today and tonight)
issued at 302 am CST Monday Feb 8 2016

Models on track. North to northwest flow aloft. A backdoor cool
front will bring cooler temperatures to north central Nebraska
today. Frontal boundary will stall out some where along a line from
Valentine to North Platte today. Still strong flow aloft and winds
will continue strong over north central Nebraska east of Highway 83
and to the west breezy today. Winds will slowly diminish this
evening. Clouds decrease over north central this morning and then
increase from the north through the afternoon. This will inhibit
solar insolation and will keep temperatures over north central
Nebraska in the low 30s with middle to upper 30s over the remainder of
western Nebraska. Cloud cover and a light breeze will keep
temperatures in the low to middle 20s over night.

Long term...(tuesday through sunday)
issued at 302 am CST Monday Feb 8 2016

Middle Range...Tuesday and Wednesday...main forecast challenge is
precipitation. A shortwave quickly traverses the area as a weak
leeside low forms at the surface. A 250hpa jet streak also moves
south along the Missouri River...providing some enhanced divergence
aloft. The NAM...GFS...and Euro show a frontogenetical zone
stretching from the Dakotas through central/eastern Nebraska and
into the Southern Plains...with the best forcing in our forecast
area Tuesday morning and afternoon. A ribbon of middle level moisture
also exists...with the highest relative humidity generally over northern Nebraska.
Forecast soundings...primarily the NAM...also indicate low level
moisture and lift across the north early Tuesday and most of central
Nebraska late Tuesday. The GFS is much more stringent on
moisture...but a brief window of saturation occurs late Tuesday and
early Wednesday. Overall...made little adjustment to previous
forecast probability of precipitation as it seemed to follow 00z model suite well. Did use -
rasn Tuesday afternoon where surface temperatures exceed 36f...although the NAM
suggests all snow from the temperature profile in soundings. The best lift
remains below the dgz...so not expecting much in terms of
accumulation. Much of the forcing exits to the east Wednesday...with
subsidence taking over in the Panhandle. Dry air also entrains into
the middle levels across north central by 18z. Large maximum temperature gradient
expected Wednesday as 850hpa warm air advection and winds show warming and drying
across the west but 850 mb temperatures still below 0c and remnant clouds near
konl.

Long range...Thursday to Sunday...amplified northwest flow aloft
transitions to broad northwest/quasi zonal flow Sunday. Large
differences remain between the GFS and Euro in the extended period.
Temperatures are the main concern as the ece guidance is almost 20f
warmer than mex Thursday and 20f cooler on Saturday. The latter
issue stems from ecm bringing the Hudson Bay low into the Great
Lakes while the GFS swings it toward the Canadian Maritimes. The
Euro also digs a trough quickly over the weekend...perhaps
supporting precipitation...while the GFS shows more of a broad
northwest flow and dry regime. All in all...went with status quo as
confidence is low...but cooler GFS temperatures are more believable Thursday/Friday
due to remnant snow pack.

&&

Aviation...(for the 06z tafs through 06z Monday night)
issued at 1122 PM CST sun Feb 7 2016

VFR conditions for the klbf and kvtn terminals the next 24 hours.
Windy conditions will persist at kvtn overnight and Monday...with
winds decoupling after 00z Tuesday. At klbf...winds 31013g22kt
overnight into Monday morning...increasing to 32020g28kt in the
afternoon. Winds will also decouple after 00z Tuesday.



&&

Lbf watches/warnings/advisories...
none.
&&

$$

Synopsis...power
short term...Snively
long term...Snively
aviation...roberg

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