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Area forecast discussion 
National Weather Service Pocatello Idaho
255 am MDT Sat Oct 25 2014

Discussion...WV imagery is showing a closed upper low off the
Oregon coast this morning with high clouds streaming across northern
Idaho. NAM shows signature of a weak cold front passing through
southeast Idaho later this evening and develops showers over the
southeastern Highlands while GFS and sref focus precipitation ahead of
upper trough axis in the central mountains. Snow levels drop to
around 4500-5500 feet as the trough passes...but most of precipitation
should be over by then. Thus snow accumulations should not amount
to much except in the highest peaks. Overall accumulations will be
about 3 to 5 inches in the central mountains and perhaps 1 to 2
inches in the southeast Highlands. Winds today and tomorrow will
be breezy...but impacts at this point look fairly low. Frontal
passage will have temperatures much cooler tomorrow with highs 15 to 20
degrees cooler. Upper trough will linger through Monday morning with
weather becoming a little more settled by the evening. Long-term
models maintaining a rather moist flow over Idaho through a weak
upper ridge...so keeping probability of precipitation mostly focused on central mountains
and some chance probability of precipitation in the southeast Highlands. Drier weather is
expected in the latter half of the week. Hinsberger
&&

Aviation...increased southerly flow today ahead of approaching
system. Surface winds 15-20kts through snake plain and higher elevations
with good support at middle levels for gusts 30kts. Weak surface boundary
passes through overnight with wind shift toward southwest and onset
of precipitation. Showers begin overnight and spread across the region
early Sunday. VFR/breezy today and tonight for kbyi/kpih/kida. Will
likely remain VFR at ksun through tonight as well though ceilings
lower. Onset of precipitation before 12z could initiate mixed MVFR
conditions. Temperatures remain warm enough pre-frontal boundary to stay
rain even at ksun. Dmh
&&

Fire weather...upper trough continues to push inland today.
Increasing southerly flow ahead of trough with 700mb winds roughly
30kts. Breezy 15-20mph winds through snake plain and higher
elevations. Humidities mainly >20pct but could see a few areas with
elevated conditional concern. Precipitation arrives overnight with weak surface
boundary/wind shift as trough axis shifts inland and deamplifies.
Best chance for precipitation most areas occurs on Sunday with cold front
passage midday. Increased surface gradient but weaker middle level flow.
Could still be enough for 20-25mph winds especially Post-front. Much
colder air and precipitation support higher humidities. Dmh
&&



Pih watches/warnings/advisories...none.
&&

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