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Area forecast discussion 
National Weather Service Boise Idaho
246 PM MDT Sat Jul 30 2016

Short term...tonight through Monday...scattered thunderstorms are
expected from late this afternoon through the early evening hours
in southern Idaho mainly south of the Snake River. The boundary
layer remains quite dry and not much rain is expected to reach the
ground with this convective activity. Expect gusty surface winds
in the vicinity of thunderstorms. A dry cold front will move from
west to east through the area late tonight. Expect breezy
northwest winds and a 7 or 8 degree drop in temperatures behind
the front on Sunday. This will still be seasonably hot as we are
at the climatological warmest time of the year. Temperatures will
once again climb to about 5 degrees above normal on Monday under
clear skies.

Long term...Monday night through Saturday....long term...Monday
night through Thursday...breezy conditions through Wednesday as
an upper- level closed low transitions across the Pacific
northwest. Two dry cold fronts associated with the pattern are
expected to move through the region sequentially. The first will
come Monday night and the second Tuesday for decreasing
temperatures each day, reaching about 7 to 10 degrees below the
seasonal normal Wednesday /10 to 15 degrees below monday's high/.
Upper level flow will be out of the southwest at first, but will
turn to the northwest by Tuesday night as the trough axis passes
through the region. A developing trough along the Pacific coast
will put the region back under a southwest flow Thursday, allowing
temperatures to rise to about normal.

Thursday night through Saturday...models are in fairly good
agreement in showing an upper low in British Columbia Friday as well
as some monsoonal moisture pushing up north, however they differ on
how these two features will progress. GFS wants to bring some
monsoonal moisture into southern Twin Falls County Friday night and
keep the upper low further north while the European model (ecmwf) brings the low
further south and keeps the monsoonal moisture out of the area.
Confidence is low at this time because of this disagreement so left
forecast dry for now. Temperatures hover right around normal for
this time period.


Aviation...VFR. Isolated thunderstorms today mainly south of a kreo-
kboi-ksnt line. Scattered thunderstorms expected along the Idaho-Nevada
border, north to the Snake River. Thunderstorms expected to taper
off before 06z. Smoke layers with MVFR visibilities will continue in
the Lowman area and surrounding valleys. Also expect smoke to filter
back into the Snake River Plain with local MVFR visibilities
overnight. Surface winds generally west-northwest 12 kts or less, with gusts
to 20 kts in southeast or and along ridgelines, diminishing before
midnight. Gusts to 40 kts near thunderstorms. Winds aloft west 15-25
kts through 10k feet mean sea level.

Outlook for Sunday...mainly VFR. Smoke will continue in the Boise
Mountains, filtering into the Snake River Plain overnight through
the morning hours. Otherwise expect mostly clear skies and breezy
northwest winds.





Boi watches/warnings/advisories... flag warning until midnight MDT tonight idz423-426.




Short term...jb
long term....ab/jc

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