Area Forecast Discussion
Issued by NWS Billings, MT

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FXUS65 KBYZ 221505

Area Forecast Discussion
National Weather Service Billings MT
905 AM MDT Mon Jul 22 2019

Fog in southern Carter county has dissipated, but there remains an
area of lower clouds west of KBIL that is slower to erode due to
upsloping boundary layer winds. Satellite imagery shows a
shortwave lifting thru the northern great basin that produced some
early morning lightning in OR/ID, and in fact we are seeing some
weak echoes pop up in south central MT near Dillon and Ennis
already. We will see scattered convection later today over the
mountains/foothills (beginning around noon in the high country),
with a cold pool perhaps taking storms as far east as Roundup-
Columbus this evening. Not much shear and moisture is high-based,
so expect gusty/erratic winds near any storms. Temps will be
hotter today with highs upper 80s to around 90 many places. JKL


.SHORT TERM...valid for Tdy and Tue...

A ridge moving over montana will bring increased heights through
the next couple days, allowing temperatures to rise to the mid 90s
by Tuesday.

Although containing fairly warm temperatures aloft, convection
over the mountains are expected in the afternoons and evenings of
Monday and Tuesday, and may move into the foothills as well due to
ample instability present in our western districts. A shortwave is
also expected to pass through south-central Montana each evening,
providing some, albeit weak, lift to help initiate storms over
the mountains. Good agreement in EC ensembles of PWATs up to an
inch are also present in the mountains and foothills, so the main
avenue for impact is localized heavy rain with these storms.
Storms over Tuesday night and early Wednesday morning have
slightly higher chances to move further out into the lower
elevations, possibly to Billings, but confidence is too low to
assume that possibility at this point.


.LONG TERM...valid for Wed...Thu...Fri...Sat...Sun...

The strong ridge over Montana will continue into Wednesday with
above normal temperatures. However, a ridge crashing trough
will track through Canada late and drag a Pacific front through
our region Wednesday night into Thursday. At this time, the
frontal passage looks mainly dry. Behind the front we should see
much drier air and a marginal cool down to average July
temperatures for Thursday and Friday with ridging gradually
building back up over the region. Deterministic model progs
indicate some perturbations in the mean flow affecting our CWA
Friday night into Saturday. So low PoP`s seem reasonable as we
head into the weekend. Then another dry ridge crasher is possible
Sunday evening. BT



An area of low clouds w/ MVFR ceilings from near K3HT to west of
KBIL will slowly dissipate through late morning. Otherwise, VFR
conditions will prevail today and tonight. Expect isolated to
scattered showers/thunderstorms west of KBIL late today, mainly
over the mountains and foothills. Brief MVFR and mountain
obscurations possible with any heavier showers. JKL



    Tdy Tue     Wed     Thu     Fri     Sat     Sun
BIL 090 064/095 066/097 061/089 060/091 064/090 062/088
    0/U 01/U    21/U    10/U    00/U    00/B    10/U
LVM 088 058/092 058/091 052/087 052/089 057/086 054/084
    2/T 33/T    21/U    10/U    01/U    11/B    21/U
HDN 090 063/095 066/096 060/088 058/090 063/090 060/087
    0/U 01/U    11/B    10/U    00/U    00/B    21/U
MLS 086 063/094 067/096 063/087 059/089 063/090 062/086
    0/U 01/U    11/U    20/U    00/U    00/B    20/U
4BQ 084 061/092 065/094 062/085 059/087 062/088 061/086
    0/U 01/U    11/B    20/U    00/U    01/B    21/U
BHK 082 059/089 063/093 063/084 057/087 061/087 060/084
    0/U 00/U    12/T    30/U    00/U    01/B    21/U
SHR 088 059/094 062/093 058/086 057/089 060/088 058/086
    1/U 23/T    21/B    21/U    01/U    11/B    21/U




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