Area Forecast Discussion
Issued by NWS Billings, MT
FXUS65 KBYZ 300916
Area Forecast Discussion
National Weather Service Billings MT
316 AM MDT Sun Apr 30 2017
.SHORT TERM...valid for Tdy and Mon...
Today will start out with clear skies across much of the region,
but will see increasing clouds from west to east beginning by mid
morning. Another period of unsettled weather will begin today as a
cold front crosses the region. Showers reach the western
mountains by late morning, spread across western zones by late
afternoon, and across the rest of the area by late evening. Cold front
will also bring breezy conditions across the area.
Unsettled northwest flow persists behind the cold front through
Monday night. Generally weak energy and additional Pacific
moisture are progged across the region, pointing to periods of
scattered showers to start the work week.
As for temperatures...highs will climb into the 60s today ahead
of the cold front. Temps will be a few degrees cooler for Monday.
.LONG TERM...valid for Tue...Wed...Thu...Fri...Sat...
Shortwave passage in unstable NW flow will bring showers and a
few t-storms Tuesday into Tuesday night, along with below normal
temperatures. With low freezing levels in place, small hail or
graupel is likely to occur in any heavier showers. For the
mountains, NW aspects will be favored for something on the order
of 3-6 inches of snow. Precipitation will taper off Tuesday night
as heights build from the west, but a few showers may linger into
early Wednesday morning near the Dakotas border as PV finally
exits to our east.
Much warmer and dry is the theme for the latter half of the week,
as a strong ridge aloft builds over the region. Expect temps back
to the 60s Wednesday and 70s Thursday. Latest model runs continue
the trend of the past couple days, showing an omega block setting
up over the country...with a deep low settling along the Pacific
coast to our west, ridging over the central CONUS, and a cold trof
over the east. This will extend our period of warmth and hold off
any real chance of precip til the weekend. With confidence, have
raised temps to the upper 70s/lower 80s Friday and Saturday, with
warmest temps in our east by Saturday. This overall theme is
agreed upon by the 00z GFS/ECMWF and GEFS. It should be noted
that, if the western low continues to trend further west, it would
open the door to backdoor fronts from Canadian shortwaves to our
north, but that isn`t likely to occur before Sunday. Should also
point out that if we really see 700mb temps near +10C by Saturday,
we are talking about mid 80s to near 90F for highs, which would
be near records for May 6th. Will need to watch model trends. As
for shower potential, have introduced a slight pop only in our far
west Friday afternoon and evening, then again Saturday afternoon.
Better chance of precipitation (and perhaps a more widespread
threat of t-storms) should hold off til Sunday.
A string of above normal temperatures like we are expecting will
get mountain snow melt going. Expect rises on rivers and streams
by late in the week. Something to think about if you have outdoor
plans next weekend.
Patchy valley fog is possible in southeast parts from KSHR to K4BQ
early this morning, otherwise VFR conditions will prevail today. A
Pacific disturbance will bring scattered showers and gusty
westerly winds, mainly this afternoon and evening. Local MVFR is
possible in these showers, and mountains will become frequently
obscured in snow showers. Expect gusts of 15-30 kts across much
of the region. JKL
.PRELIMINARY POINT TEMP/POPS...
Tdy Mon Tue Wed Thu Fri Sat
BIL 062 040/058 040/055 039/067 045/076 049/081 050/079
2/W 33/W 45/T 30/U 00/U 00/U 11/B
LVM 058 034/054 034/052 031/065 040/075 044/078 044/073
3/W 32/W 45/T 30/U 00/U 02/W 22/W
HDN 064 040/060 039/056 036/066 041/077 046/081 047/080
2/W 53/W 35/T 31/B 00/U 00/U 11/B
MLS 065 043/059 039/059 038/066 044/076 050/080 050/081
2/W 43/T 23/W 21/B 00/U 00/U 11/B
4BQ 063 041/057 038/057 036/063 039/074 047/078 049/082
1/U 43/W 24/W 22/W 00/U 00/U 01/B
BHK 062 038/055 035/057 035/061 035/071 043/074 046/079
1/U 34/T 23/W 22/W 00/U 00/U 01/B
SHR 056 036/052 036/051 034/061 038/072 041/078 041/078
1/B 33/W 35/T 31/B 00/U 00/U 02/W