Scientific Forecaster Discussion
Area forecast discussion...updated
National Weather Service Billings Montana
848 PM MDT Tuesday Sep 2 2014
Minor tweak to the forecast this evening to adjust relative
humidities higher. Otherwise forecast is on track. Thermal low/Lee
side trough over western zones is delineating very dry air and
still gusty winds over the Livingston and foothills areas from
light winds and higher relative humidities to the east. Otherwise
mostly clear conditions can be expected tonight and current
forecast has this covered.
Upper low is digging south along the northwest coast this evening
and will drive a cold front through the area tomorrow morning for
western zones...and into the afternoon east. As this system
approaches will see southwest winds expand to the east with pre-
frontal trofing...probably before sunrise for areas west of
Rosebud County. Looks like a breezy morning ahead of the front
tomorrow followed by a somewhat windy afternoon as winds turn
northwesterly behind the front. A lack of moisture will limit
precipitation chances significantly with the best chances being
along and north of a Livingston to Miles City line tomorrow.
Short term...valid for Wednesday and Thursday...
Mostly clear skies and dry conditions will prevail for the
remainder of this afternoon and through the overnight hours.
Afternoon temperatures are currently about 5 to 10 degrees warmer
than this time yesterday. This along with slightly warmer 850mb
temperatures will equate to overnight lows about 5 to 10 degrees
warmer as well with readings mainly in the upper 40s to lower 50s.
A cold front will move across the western portions of our
forecast area by late morning or early afternoon Wednesday and our
far southeast counties by late afternoon. The bulk of the upper
level energy looks to stay to our north as an upper low moves
across the Canadian border. As a result...expect the majority of
the shower activity to be across the northern portions of the
state. However...there will be a slight shower/thunderstorm chance
along and north of a Livingston-Billings-Miles City-Baker line.
The main impact the front will bring will be gusty northwest winds
behind the front Wednesday afternoon into Thursday morning
especially for areas east of Billings.
High temperatures Wednesday will be in the upper 60s across the
far west as the front moves through there by early afternoon with
readings in the lower 80s across the far southeast due to the
later arrival of the front. Temperatures Thursday will be much
cooler with readings only in the lower to middle 60s. Hooley
Long term...valid for Friday...Sat...sun...Mon...Tue...
Dry northwest flow aloft will be over the area Friday with weak
embedded energy moving over the region. Models still indicating
moderate qg forcing moving through but does not generate any quantitative precipitation forecast
values over the mountains or plains. Will keep dry forecast in
place. Weak ridging building over the area this weekend and this
will result in warming temperatures as a surface thermal ridge
develops. Should see highs slightly above normal with upper 70s to
lower 80s. Upper ridge breaking down Monday as a long wave trough
moves in from the West Coast. Moisture again looks limited with
this trough and only isolated showers expected over our far
western zones and Southwest Mountains. Upper trough will drag a
cold front southward during the day Monday and strong mixing ahead
of the front will bring another warm day with upper 70s expected.
Strong forcing with this wave will bring a chance of showers and
thunderstorms. Much cooler air mass over the area on Tuesday and
this will keep the atmosphere unstable aloft for a continued
chance for showers. Temperatures also falling with middle 60s
expected for highs. Richmond
VFR conditions expected tonight. Will continue to see gusty west
to southwest winds along the western foothills through the night
including the klvm taf site. Chambers
Preliminary point temp/pops...
Wednesday Thursday Friday Sat sun Monday Tuesday
bil 054/075 046/065 046/070 049/075 050/078 054/079 053/066
02/T 11/b 01/b 11/b 11/u 11/u 22/T
lvm 045/073 039/065 037/070 041/074 043/077 048/078 046/066
02/T 11/u 01/b 11/b 11/u 22/T 22/T
hdn 052/077 050/065 049/073 050/077 052/080 054/082 053/069
01/north 11/b 01/b 11/b 11/u 11/u 22/T
mls 054/078 049/065 047/072 051/077 052/081 057/082 055/067
11/u 21/b 11/b 11/u 11/u 11/u 22/T
4bq 053/083 050/064 048/072 050/077 052/081 056/082 056/067
01/u 11/b 11/b 11/u 11/u 11/u 22/T
bhk 049/079 046/064 043/069 048/073 049/078 054/080 055/071
11/u 21/north 11/b 11/u 11/u 11/u 22/T
shr 048/081 044/066 043/071 045/075 048/079 052/081 051/067
01/u 11/u 12/T 21/b 11/b 22/T 22/T