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Area forecast discussion 
National Weather Service Boise Idaho
922 am MDT Mon Oct 24 2016

Discussion...a broad area of moist southwesterly flow remains in
place this morning and will linger into the overnight hours
tonight. Sounding data along with surface observations indicate
that little to no precipitation is reaching the surface across the
area. Have updated this morning to add in the threat of isolated
showers for portions of Baker County and higher terrain along the
or/Idaho border north of Ontario. Any precipitation will be very
light with little to no accumulation. This afternoon there will be
a slightly better chance of showers, with even a few thunderstorms
possible over the upper snake plain and Magic Valley. Other areas
may get in on the action if there are breaks in the cloud cover
allowing for additional heating. Winds will also become quite
gusty from the south to southeast today ahead of an approaching
front. No further updates are planned this morning, see previous
discussion for additional details.


Aviation...VFR. Increasing mid-high level ceilings. Scattered
showers across the region with only light precip expected in the
valleys. Isolated afternoon thunderstorms over central and southwest
Idaho, mainly east and south of kboi 18-00z. Scattered showers again
Tuesday. Surface winds: generally south to southeast 10-20 kts, with
15-30 kts expected across southeast or and in the Treasure valley between
kboi and kmuo after 18z and diminishing around 06z. Winds aloft up
through 10kft msl: southeast 20-30 kts, becoming 40-50 kts 03-09z over southeast


Previous discussion...
short through Tuesday...moist southwesterly flow
ahead of deepening upper level low off the West Coast will keep
mainly mid to high level clouds across the area today. Weak
shortwave and strong upper level jet will move over the forecast
area this afternoon and interact with a moisture plume pushing
northward from the southwestern U.S. To initiate showers across
southcentral Idaho. The best chance for showers favors the higher
terrain of southwest Idaho and the western Magic Valley. There
could also be enough instability for thunderstorms again favoring
the higher terrain. Winds will also increase today for breezy
conditions across most of the forecast area. Southwesterly flow
aloft and breezy southeasterly winds at the surface today favors
shadowing and/or virga showers for the Treasure valley today and
tonight. Latest guidance is significantly lower on quantitative precipitation forecast amounts for
Tuesday as the cold front stalls out near the Idaho/Oregon border
and the moisture plume from California coast gets cut off. A few
high-res models are now showing a weak shortwave passage Tuesday
afternoon which could be enough for light showers across the
forecast area so have left chance to likely pops.

Long term...Tuesday night through Monday...our County Warning Area will remain
under southwest flow aloft between an upper level trough off the
coast and an upper-level ridge over central North America. This
pattern will keep temperatures 5 to 10 degrees above normal, with
showery periods as weak weather disturbances cross the area. Tuesday
night through Thursday precipitation will be mainly confined to
northern portions of Harney and malhuer counties and the central
Idaho mountains. On Friday an upper-level trough from California
promises to bring a better chance of precipitation for the entire
area, as models are currently in sync with this feature. Timing is
less certain for a second trough Sunday night and Monday.


Boi watches/warnings/advisories...



previous short term...jds
previous long term....jt

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