Sidney, Montana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

754
FXUS65 KGGW 201921
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
121 PM MDT Sun Jul 20 2025

.DISCUSSION...

KEY MESSAGES:

- Scattered thunderstorms will exit to our east this evening.

- More widespread thunderstorms are expected Monday night into
  Tuesday with heavy rain possible.

- Seasonable temperatures will trend below average by the middle
  of the week. A warm up then is expected later in the week.

WEATHER PATTERN OVERVIEW:

An upper low over southwest Canada will dig a trough into the
Pacific Northwest the next couple days, putting the CWA in a SW
upper flow Monday. The the trough gradually lifts out for some
warmth later in the week. However, another upper low from Alaska
could bring a return to showers next weekend.

Instability over eastern Montana will bring scattered strong to
possibly severe storms again this afternoon into the early evening
hours. Models continue to differ on the strength and placement of
these storms, so confidence is shaky on how things pan out the
next 6 hours. But models agree that things move to our east later
this evening with drying tonight.

Monday will feature morning sunshine that will help to destabilize
things across the area once again. With the SW flow in place,
thunderstorms will move northeast. With higher humidity than
normal in place, more widespread coverage is expected. These
showers/storms should be brief enough for no widespread flooding/flash
flooding concerns at this time.

On Tuesday and Wednesday, another round of mainly late-day
showers/storms look to move northeast into the CWA, but rainfall
should be lighter. It will also be quite cool for late July with
highs mainly in the 70s.

Warmer and mainly dry conditions return later in the week as the
upper trough slowly lifts out. But there are signs that another
disturbance brings a return to unsettled conditions next weekend.

FORECAST CONFIDENCE & DEVIATIONS:

Pops were adjusted in the near term for consistency and
collaboration. Otherwise, NBM numbers were followed. TFJ

&&

.AVIATION...

FLIGHT CONDITIONS: VFR conditions are expected overall but brief
IFR/MVFR ceilings and visibilities are possible with
thunderstorms later today and again Monday night.

An upper trough over western Canada will keep conditions unsettled
over the area the next several days. Expect several days with
showers and thunderstorms into mid-week.

WINDS: Expect gusty and shifting winds near storms later today.
Otherwise, winds look to be light and variable until they increase
from the NE late Monday. TFJ

&&

.GGW WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

weather.gov/glasgow