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Area forecast discussion 
National Weather Service Boise Idaho
830 PM MDT Friday Jul 3 2015

Discussion...thunderstorms along the Nevada border reached maximum
development and northward extent around 00z but have already dissipated.
No other storms expected tonight. Another hot day on the Fourth of
July but a little cooler Sunday as an upper trough passes by in western
Canada. No updates.


Aviation...VFR. Scattered-broken middle level and high clouds through Saturday
morning. Surface winds...mainly northwest 10-15 kts decreasing to
less than 10 kts by 06z. Winds aloft...northwest 10-20 kts up
through 10k feet mean sea level.

Weekend outlook...isolated afternoon and evening thunderstorms...on
Saturday south of the Snake River Valley in Idaho and the southern
halves of Harney and Malheur counties in Oregon...spreading north
over Idaho on Sunday to the Snake River Valley east of kboi...and
the Boise and west central Idaho mountains.


Previous discussion...
short term...tonight through Monday...upper level ridge remains
centered over Utah with the axis going through northern Nevada and into
northern California. This is inhibiting moisture from moving very far north
across the Nevada border. We have a slight chance of showers and
storms near that border this afternoon and evening. A trough will
move by to the north tomorrow...passing through northern Idaho and into
Montana. This will draw moisture northward and extend the chance
for showers and storms farther north into our County Warning Area tomorrow
compared to this afternoon and evening. Precipitable water values at kreo go from
approx 0.80 this morning up to around an inch tomorrow afternoon
according to NAM forecast soundings. Sunday...the ridge axis
slides slightly north...keeping the chance of storms restricted to
the south and east. Temperatures will cool slightly in the wake of the
trough that passed by to the north on Saturday. Monday will be
nearly a Carbon copy of Sunday as the ridge axis moves very
little. Winds will be light apart from showers and storms...where
a significant gust threat exists owing to very dry lower levels of
the atmosphere.

Long term...Monday night through Friday...the upper level ridge will
weaken a broad upper level trough along the Canadian
border extends south into Idaho. Meanwhile...a closed upper level
low will slowly track northeast over California - finally
reaching eastern Oregon and southwestern Idaho by middle-day Friday. This
pattern shift will bring some respite from recent triple digit
temperatures...with valley highs forecast to peak in the 90s
Wednesday through Friday. Also...improved model agreement
regarding the movement of the closed low warrants increased
confidence in convection. Therefore...have increased probability
of middle-week showers and thunderstorms - especially south and west
of the Snake River.


Boi watches/warnings/advisories...



previous short term...snow pellets
previous long term....Mt

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