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fxus65 kboi 241944 

Area forecast discussion
National Weather Service Boise Idaho
144 PM MDT Fri Mar 24 2017

Short term...tonight through Sunday...two Pacific systems will
bring precipitation to our County Warning Area. Showers from the first system will
arrive in the Magic Valley by this evening as precipitation tapers
off in eastern Oregon. Most lower elevation areas will see showers
ending by Saturday morning, but isolated showers are still possible
in the valleys in the moist unstable air. Scattered snow showers
will continue over the mountains above 5000 feet through the day. A
temporary high pressure ridge will provide a brief respite from
precipitation Saturday night and Sunday morning, but more showers
will spread into eastern Oregon and the mountains of southwest Idaho
Sunday afternoon as the next system approaches.

Long term...Sunday night through unsettled pattern
to continue through the long term. A Pacific trough will bring
widespread shower activity Sunday evening which will continue
through Monday evening. Cooler temperatures anticipated in response
to this system. A break in widespread moisture expected into
Wednesday, though the associated ridge is dirty, and may skirt a few
showers across the northern border of the forecast area.

Wednesday night through Friday...pretty wet for the County Warning Area for
Wednesday night into Thursday as a Pacific system pushes through the
area. A ridge begins to build over the Pacific northwest come Friday
morning helping to dry things out for most of the County Warning Area. Snow levels
begin around 6500 feet mean sea level or higher then drop slightly come
Thursday night as the boundary pushes through. Snow levels bottom
out around 4000 feet mean sea level Friday morning before climbing back above
5500 feet mean sea level by Friday night. While the snow levels drop, most of
the precipitation has pushed out of the area so only higher
elevations in the west central and Boise Mountains as well as the
Owyhee Mountains and southern Twin Falls County will see some snow
showers. Temperatures Thursday will sit right around normal for this
time of year then climb to above normal Friday as the ridge builds


Aviation...increasingly MVFR. Shower coverage will continue
to increase this afternoon resulting in potentially widespread MVFR
conditions. Mountain obscuration expected with low ceilings. Surface
winds: south to southeast 10-15 kts, except over southeast Oregon
where speeds could be 15 to 20 kts. Gusts 25 to 30 kts. Winds become
light and variable after 06z this evening. Winds aloft near 10k ft
msl: southwest 30-45 kts.

Weekend outlook: VFR expected by Saturday evening as transitory
ridge builds over the area. These VFR conditions will persist
through Sunday morning for all terminals. Another approaching
Pacific system will begin to push moisture into southeastern Oregon
after 15z on Sunday, with activity moving into southwestern Idaho by
Sunday afternoon. MVFR conditions anticipated with this next
moisture push, as well as another round of mountain obscurations.
Scattered shower activity expected to remain through Sunday night
and into Monday.


Hydrology...most rivers and streams will rise over the weekend in
response to precipitation today and this evening, but they will stay
below flood stage. Exceptions are the Snake River at Weiser and the
Boise river at Glenwood bridge, which will remain above flood stage
through the coming week. Several hydrologic warnings and advisories
remain in effect. Cooler temperatures and snow above 6000 feet will
limit the amount of inflow from higher elevations.


Boi watches/warnings/advisories...




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