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fxus65 kboi 161000 

Area forecast discussion
National Weather Service Boise Idaho
300 am MST Sat Dec 16 2017

Short through Sunday...snowfall continues to move
through the western Magic Valley this morning as the trough
continues to sweep through the area. Most snowfall is expected to
taper off by the late morning hours. North-northwesterly flow,
associated with a ridge off the Pacific coast, will then return
to the area and is expected to last into Sunday. This system will
return inversion conditions late tonight and through Sunday, with
the potential for some low stratus and patchy fog. Patchy dense
fog will be possible on Sunday morning, but pinpointing this
development remains a challenge. For now, patchy fog wording will
remain. Temperatures will be able to warm today, with values much
closer to seasonal normals. However, temperatures will again cool
on Sunday due to the influence of the inversion. Weak amounts of
moisture in the flow may produce a few showers across Baker
County, or and into the west central mountains of Idaho on Sunday
afternoon. Coverage will not be significant, with any snowfall
having minimal impacts.

Long term...Sunday night through Friday...Sunday night through
Tuesday moist relatively warm westerly flow aloft will provide
scattered snow and rain showers for Baker County Oregon and the
central Idaho mountains, with snow levels around 4000 feet.
Tuesday night and Wednesday a strong cold front, followed by a
deep upper level trough from the Gulf of Alaska, will bring
widespread precipitation, with snow levels lowering from around
4000 feet Tuesday night to the valley floors by Wednesday evening.
The trough will move south of our area Wednesday night, replaced
by northerly flow aloft over the intermountain region starting
Thursday. Temperatures are not expected to be unusually cold, with
readings in the valleys Thursday and Friday close to what they
were during the inversion of the past week, but with considerably
less cloud cover.


Aviation...mountain obscuration and areas of IFR/LIFR ceilings
will persist this morning. Snow showers in the Magic Valley will end
by around 12z. Expect some improvement after 18z, with areas of MVFR
ceilings and mainly VFR visibilities. Conditions will deteriorate
after 00z, with areas of low stratus and patchy fog forming in most
valleys. Surface winds will be northwest 5-15 kts. Winds aloft at
10k ft mean sea level will be north 20-30 kts.


Boi watches/warnings/advisories...




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