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Area forecast discussion 
National Weather Service Billings Montana
251 am MDT Thursday may 7 2015

Short term...valid for today and Friday...

Early this morning...radar returns are already beginning to
increase over the southwestern mountains and foothills. This is
associated with a short wave moving out of Utah.. as this
continues to move north...rain chances will increase through the
morning. Winds across the area are going to remain out of north to
northeast. With the upslope component along with the area still
somewhat in a favorable region of a 250mb jet...and throw in some
qg forcing...rain looks likely over the mountains and western
zones during the day today. Hi-res guidance show precipitation pushing
almost to Billings...so have left a slight chance in for the city.
Most of the rain associated the a shortwave in the Dakotas has
already moved out of Montana. Have removed probability of precipitation from most of cater
and Fallon counties...leaving much of the area east of Billings
and Sheridan dry through the day.

Overnight rain chances will decrease some as this around of energy
dissipates...but the best chances in the short term will be
Friday evening. As the closed low moves into The Four Corners
region...the area will see another round of energy move in. Winds
will shift to more easterly during the day Friday and moisture
will be increasing. This will combined with increasingly diffluent
flow aloft to give much of the area a shot at rain. Temperatures
at 850mb continue to be in the 0 to +3 degree range across the
area. In the mountains this will result in snowfall of 2 to 4
inches...some locally higher amounts closer to 6...Friday into
early Saturday. The foothills will see less...generally a couple
of inches over 24 hours. Maintained the previous forecast of only
rain in Billings and points further east as guidance continues to
show wetbulb temperatures remain slightly above freezing. Reimer

Long term...valid for Sat...sun...Mon...Tue...Wed...

Medium range guidance in fairly good agreement into the extended.
Saturday still looking like a cool and wet day under upper
diffluent flow ahead of upper low drifting east across the
southern rockies. As system spins up into the plains...a drier
northwest flow pushes into most of our area for Sunday. The main
changes into the extended was to lower precipitation chances for
Sunday with the system trending further southeast. As upper low
drifts east into the Midwest...a north/northwest flow dominates
into Tuesday for overall dry conditions. Once Wednesday
approaches...introduced climatology precipitation chances as flow becomes more
southwest again and instability increases across the region. No
organized system...just mainly scattered afternoon showers.

As for temperatures...readings could be as much as 20 degrees
below normal for Saturday if the cloudy and wet conditions evolve
as expected. A slow moderation in temperatures expected the rest
of the extended. The northwest flow behind the weekend system will
keep temperatures below normal into Monday. Frieders

&&

Aviation...

Showers will occur in the mountains and foothills into this
evening. Expect local MVFR along the foothills with frequent
mountain obscurations. Otherwise...VFR conditions will prevail
with a middle level cloud deck. Frieders

&&

Preliminary point temp/pops...

Today Friday Sat sun Monday Tuesday Wednesday
-------------------------------------------------------
bil 052 038/047 036/043 035/053 035/058 038/065 044/069
2/west 14/west 77/r 61/b 11/b 11/b 12/west
lvm 049 033/046 033/044 032/051 030/057 035/063 038/066
7/west 26/west 77/o 52/west 12/west 22/west 33/west
hdn 055 036/054 036/045 033/055 033/060 034/066 041/070
1/east 13/west 77/r 61/b 11/b 11/b 12/west
mls 056 036/056 037/050 033/055 034/060 038/064 042/069
1/east 12/west 55/r 31/b 10/b 11/b 12/west
4bq 055 034/058 038/045 031/050 032/056 034/062 041/068
1/east 12/west 66/r 62/west 10/b 11/b 12/west
bhk 054 032/056 034/050 031/051 031/056 034/059 038/065
1/east 11/east 34/r 21/b 10/b 11/b 12/west
shr 052 033/053 035/041 030/047 030/054 033/062 039/066
4/west 14/west 78/o 63/west 21/b 11/b 12/west

&&

Byz watches/warnings/advisories...
Montana...none.
Wyoming...none.

&&

$$
Weather.Gov/Billings

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