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Area forecast discussion 
National Weather Service Billings Montana
311 am MST Friday Feb 27 2015

Short term...valid for today and Sat...

The short term forecast has not changed much. Highs for today
look to be in the upper 20s to lower 30s across much of the area.
Clouds will be on the increase during the day as weak trough
moves out of British Columbia into the northern rockies. As this
system moves through...there will be some q vector convergence
along with some middle level moisture...moving in later tonight.
Models continue generate some very light quantitative precipitation forecast mainly over the
southwestern mountains and foothills. This amounts to around an
inch...maybe two...of snow in the Saturday
afternoon. Temperatures will remain below normal through remainder
the short term. Lows will not be as cold as currently occurring
across the area. Reimer

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

No big changes to the extended forecast this morning. Downslope
northwesterly flow will provide a warming trend from Cold Saturday
temperatures Sunday and Monday along with dry conditions. Flow
amplifies and becomes northerly Monday night with a strong system
dropping down The Spine of The Rockies. This will bring a good
chance of snow to the western half of the forecast area Monday
night into Tuesday. A 1038mb surface high will usher in another
quick shot of cold Canadian air for Tuesday with highs in the
single digits and teens. GFS is the coldest model at this point
and holds cold air in a bit longer than the European model (ecmwf)...but
differences are pretty minimal considering the event is 5 to 6
days out. Cips analogs showing the potential for lower elevation
advisory type snowfall for areas west of a Roundup to Ashland
line...with potentially heavier accumulations for northerly
upslope favored foothills and mountain areas including the Red
Lodge and Nye vicinities. System shifts southeast on Wednesday for
dry conditions and a return to a downslope wind regime.
Temperatures will begin to climb back toward normal by Thursday
and Friday next week...with the European model (ecmwf) showing the potential for
another chance of snow late Friday into Saturday but not as much
cold air. Chambers


MVFR ceilings will persist into middle morning over western
foothills locations including the klvm taf site. This activity
dissipate middle morning as winds shift to a westerly downslope
direction. Another small area of MVFR ceilings/visible may develop
over river valleys in central zones around Billings (see
discussion below) which should also dissipate middle morning.
Otherwise VFR conditions can be expected today. A disturbance
dropping through the area tonight will bring scattered snow
showers tonight into Saturday. Local MVFR conditions can be
expected with this precipitation activity.

For kbil this area of stratus and possibly some fog
is showing up on satellite over the northern Big Horn basin
stretching north into the Clarks Fork River Valley south of
Billings. As surface high pressure continues to slip east of the
state Lee side trofing may be strong enough to pull this stratus
and fog into the Billings area around sunrise for a brief period
of sub VFR activity. Its not a sure thing that this activity will
get into Billings but will adjust taf to mention possibility and
will amend as necessary. Any MVFR conditions will dissipate middle
morning. Chambers

Preliminary point temp/pops...

Today Sat sun Monday Tuesday Wednesday Thursday
bil 025 008/021 005/031 015/039 008/010 903/025 015/040
0/b 22/j 00/u 00/b 64/S 20/b 01/b
lvm 027 003/019 903/029 013/038 004/011 909/026 015/038
2/j 55/j 20/u 01/b 74/S 21/b 11/b
hdn 028 008/024 004/034 012/041 009/012 903/024 011/040
0/u 22/j 00/u 00/u 54/S 21/b 11/b
mls 026 006/022 006/029 012/038 007/013 000/021 010/040
0/u 11/east 00/b 00/u 33/S 11/b 11/b
4bq 026 007/023 003/030 011/039 008/013 902/020 008/040
0/u 11/east 00/u 00/u 34/S 21/b 11/b
bhk 025 004/021 004/027 011/036 006/012 903/018 006/037
0/u 00/b 11/b 00/u 12/S 11/b 01/b
shr 022 004/018 901/027 007/034 007/007 910/018 007/038
0/u 13/j 11/u 00/u 55/S 21/b 01/b


Byz watches/warnings/advisories...



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