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Area forecast discussion...updated 
National Weather Service Billings Montana
544 am MDT Wednesday may 6 2015

Short term...valid for today and Thursday...

Cool and showery weather on tap for the next couple of days. A
large upper low and trough currently over the Pacific northwest
will slowly shift south into the Great Basin area by Thursday and
over The Four Corners region on Friday. This low will provide for
a diffluent flow aloft across southern Montana and northern
Wyoming for the next couple of days. Currently...a jet streak over
western Montana with the right entrance region across our area is
resulting in a continuous band of showers moving south to north
from northern Wyoming into our central locations this morning.
This band of showers will continue through the middle morning hours
for portions of Carbon...Big Horn and all of Yellowstone and
Musselshell counties where categorical to likely probability of precipitation will be in
place through noon. The band of showers will slowly shift east
during the afternoon...and this combined with a developing surface
low across western Nebraska will result in likely to categorical
probability of precipitation this afternoon through tonight for our eastern areas.
Elsewhere...isolated to scattered showers can be expected this
afternoon through tonight. As for thunderstorm
activity...atmosphere is more stable than the past two days and
have removed thunder mention from the eastern zones for today.

The upper low digs far enough south on Thursday to give our area
a break in the precipitation for the most part. Models are in fairly good
agreement in keeping the bulk of the showers to our south and east
across Wyoming and the Dakotas. So best chances for showers will
be the beartooth/absaroka and Big Horn Mountains and areas out
toward the Dakota borders. As for temperatures...yesterday was the
warmest day will we will see for at least a week. A cool easterly
surface flow combined with shower activity will keep our readings
below normal for the remainder of the week. Temperatures today
will struggle to get to the lower 60s at best with even chillier
temperatures for Thursday with readings in the 50s. Hooley

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

Over the past 24 hours models have been consistent with the late
week trough digging into the Great Basin and then ejecting into
the Central Plains. Models continue to keep much of the energy in
Wyoming and into South Dakota. That said...there will be diffluent
flow aloft across much of the area coincident with the trough
axis moving across. Models are continuing to show a quarter to a
half inch of liquid across southern Montana and north central
Wyoming...with maybe up to three quarters of an inch in the high
mountains late Friday through Saturday. The mountains are going to
see the highest amounts as the northerly upslope winds increase
precipitation production. Temperatures at 850mb continue to not be
overly cold...therefore while the mountains can expect to see
snow...it is going to be a wetter snow with lower snow to liquid
ratios. The foothills from Nye to Red Lodge could see 2 to 3
inches Friday through Saturday. Rain chances linger into the work
week as a weak short wave rotates across the area as the main
through move out into the plains. Temperatures will cooler through
the weekend only in the 40s for highs on Saturday...before slowly
warming back to more seasonal values by middle week next week. Reimer

&&

Aviation...

A line of showers will continue to slowly move east across the
area from Billings eastward this morning. MVFR conditions will
be possible associated with the showers....mainly east of
Billings. Otherwise...expect VFR conditions. Winds through the day
will be gusty out of the north to northwest at 15 to 20
knots...gusting 25 to 30 knots. Reimer

&&

Preliminary point temp/pops...

Today Thursday Friday Sat sun Monday Tuesday
-------------------------------------------------------
bil 060 040/055 038/049 037/044 036/051 035/060 040/066
+/r 22/west 13/west 67/west 63/west 32/west 22/west
lvm 059 036/052 033/049 034/044 032/052 032/059 036/063
6/r 33/west 35/west 66/west 54/west 33/west 33/west
hdn 059 039/058 040/054 037/046 035/053 033/061 039/067
+/r 21/east 12/west 56/west 63/west 32/west 22/west
mls 058 040/058 037/057 038/050 035/054 035/061 039/064
7/r 41/b 11/east 45/west 52/west 21/b 22/west
4bq 056 041/058 037/058 039/048 034/049 031/057 037/062
8/r 42/west 12/west 46/west 64/west 31/b 22/west
bhk 060 041/055 034/058 035/049 032/049 031/057 034/059
9/r 82/west 11/east 34/west 42/west 21/b 11/b
shr 051 038/055 034/055 037/043 032/045 028/056 035/062
7/r 42/west 24/west 57/west 75/west 42/west 22/west

&&

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

&&

$$
Weather.Gov/Billings

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