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Area forecast discussion 
National Weather Service Boise Idaho
250 PM MDT Wednesday Oct 22 2014

Short term...tonight through Friday...a moist Pacific plume to
our west will shift eastward and reach southeast Oregon and most of SW
Idaho tonight and Thursday...then stall over our area Thursday
night before shifting to the north along a warm front on Friday.
Showers associated with the moist plume will occur mainly over the
higher elevations where precipitation totals will be greatest. The only
areas that may not see any precipitation are the western Magic Valley and
southern Twin Falls County. Quantitative precipitation forecast totals /from tonight through
Friday/ will generally range from a tenth /0.10/ to a quarter
/o.25/ of an inch in the valleys...with a quarter /0.25 to half
/0.50/ inches in the mountains. Locally higher amounts are
possible. Snow showers and light snow accumulations are possible
above 7000 feet. Winds will be breezy at times...especially
Thursday afternoon. Warmest daytime temperatures will be across
the western Magic Valley Thursday afternoon...and south of the
warm front /south of a Burns-Boise-Fairfield line/ on Friday.

Long term...Friday night through Sunday...once the warm front
moves north...the area will transition into a southwest flow in
the warm sector ahead of yet another upper low. Good mixing with a
moderately strong pressure gradient will bring windy conditions on
Saturday afternoon as a surface front approaches. A headline may
be needed for the winds during that period...but will continue to
monitor. Frontal passage looks to occur sometime overnight
Saturday into Sunday with better chances of precipitation over the entire
area on Sunday. Winds will once again be breezy behind this front.
Snow levels for this system will rapidly drop from over 10000 feet
Saturday morning to 5000 to 6000 feet by Sunday morning. No
significant snow accumulations are anticipated with this forecast.

Sunday night through Wednesday...the trough will move out Sunday
night through early morning Monday and a drier northwesterly flow
will set in behind it. This flow pattern will be maintained until
a trough begins to move in again beginning Tuesday night for a
more sswerly flow. Temperatures will be about normal throughout
this period...increasing slightly on a daily basis. The greatest
chance of precipitation will occur over the higher terrain with
each passing trough...possibly coming in the form of snow above
5000 feet.


Aviation...VFR conditions are expected through the period for
all sites with the exception of kmyl. Overnight tonight...a few
rain showers are expected near kbno kbke and kmyl...with the
potential for kmyl to drop to MVFR ceilings. Surface winds are
expected to be breezy the rest of this afternoon and tomorrow
afternoon. Winds aloft will remain southwest at 25 to 35 kts but
will increase to almost 50 kts as Thursday wears on. Thursday
afternoon and evening will bring the threat of rain showers at


Boi watches/warnings/advisories...




long term....ep/ab

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