Area Forecast Discussion
Issued by NWS Boise, ID

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FXUS65 KBOI 250240

Area Forecast Discussion
National Weather Service Boise ID
840 PM MDT SAT SEP 24 2016

.DISCUSSION...No significant changes in forecast thinking this
evening. High pressure is folding overhead with clear skies for
all of SE Oregon and SW Idaho. Winds are expected to continue to
weaken through the night, with another round of cooler than normal
temperatures on tap. The building ridge will mean warming
afternoon temperatures through early in the week with readings
above normal in most locations. No threat of precipitation through
at least Tuesday.


.AVIATION...VFR conditions will be the rule overnight into Sunday
for all terminals. Winds will drop off to less than 8 knots for
all sites after 04Z and remain on the lighter side through 18Z


SHORT TERM...Still windy in south-central Idaho this afternoon
but winds will decrease tonight and will be much lighter Sunday.
Light winds in the rest of our CWA as well.  Large ridge of high
pressure in the eastern Pacific will build inland over all the western
states through Monday bringing clear skies and warming days.  Dry air
will allow strong radiational cooling at night and min temps will be
slower to warm.  Patchy fog will form in northern valleys early Sunday
morning, but Monday morning looks too dry for fog.

LONG TERM...Monday night through Saturday...An upper level ridge
will dominate the region Monday night through Wednesday, bringing
temperatures up to about 10 degrees above normal. The ridge will
gradually shift east while an upper level trough moves into the
Pacific Northwest the second half of the week. Temperatures will
remain above normal in southwest flow on Thursday, then cool down to
normal or slightly below normal by the weekend as the trough deepens
over the northwest. Moisture does not look great at this point so
kept pops low and focused over the higher terrain mainly north of
the Snake River Plain from Thursday night into the weekend.

AVIATION...VFR with mostly clear conditions. Surface winds
generally 10 kts or less, except for gusty winds up to 20-25 kts in
the Upper Treasure Valley and Magic Valley, tapering off around
sunset. Winds expected to be 10 kts or less Sunday. Patchy fog in
sheltered mountain valleys Sunday morning. Winds aloft near 10 KFT
MSL: NNW 20-30 kts decreasing to 10-20 kts after 25/00Z, then
northerly 10-15 kts Sunday.





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