Sidney, Montana 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

418
FXUS65 KGGW 241918
AFDGGW

Area Forecast Discussion
National Weather Service Glasgow MT
118 PM MDT Sun May 24 2026

.KEY MESSAGES...

- A warming trend will continue into Memorial Day. Highs could be
  approaching 100 degrees in some locations on Tuesday.

- Hot temperatures, low humidity, and gusty southeast winds will
  raise fire weather concerns for Tuesday.

- Scattered thunderstorms are expected by Tuesday evening moving
  in from west to east, with an isolated stronger storm possible.
  Expect chances for showers and thunderstorms to continue at
  times for the second half of the week.

&&

.DISCUSSION...

WEATHER PATTERN OVERVIEW:

Temperatures will continue to heat up across NE Montana heading
into Memorial Day thanks to an upper ridge pattern. High
temperatures by Memorial Day will be well into the upper 80s to
mid 90s for most of NE Montana while relative humidity reaches as
low as 12 to 15 percent. However, wind is expected to be light
during this time, limiting the fire weather threat.

On Tuesday as the ridge will shift over to the east, low level
southeast winds will ramp up. High temperatures will be in the
90s to near 100 with humidity readings between 10 and 20 percent.
This combination in the presence of dry fuels will likely raise
fire weather concerns. Even where green up is underway, curing
may take place from consecutive hot and dry weather days. Gusty
southeast winds may also present boating hazards for Fort Peck
Lake. Future shifts can assess the need for any heat/lake/fire
weather related headlines as confidence continues to improve.

On Tuesday evening, an upper trough will move in from the west
while thunderstorms will across central Montana. These storms
will make progress eastward into NE Montana. An isolated stronger
thunderstorm is certainly possible, with the greatest coverage
expected to be for areas west of a line through OPheim to Glasgow
to Jordan.

Wednesday through Friday will continue to feature a deep trough
across the western CONUS and a ridge to the east. NE Montana will
be sandwiched in between with thunderstorm chances each day,
especially in afternoon and evening hours. Some of the storms have
the potential to be on the stronger side and may produce brief
heavy downpours.

FORECAST CONFIDENCE & DEVIATIONS:

NBM was largely used for the forecast period. Pops were however
adjusted in the near term for Tuesday for consistency and to best
reflect thunder chances. Confidence is certainly growing on hot,
dry, and windy conditions on Tuesday leading to heat, fire
weather, and lake wind concerns, as well as convective potential
later in the day. Confidence is more moderate for the thunderstorm
coverage later in the week given the later time scales involved,
but there is decent ensemble consensus in the overall synoptic
pattern.


&&

.AVIATION...

LAST UPDATED: Sunday May 24, 2026 at 1915Z.

FLIGHT CAT RANGE: VFR.

DISCUSSION: Excellent flying weather looks to continue with mid
to high clouds moving across the terminals at times.

WIND: West at 5 to 15 kts, with a few gusts to 20 kts through this
evening. Winds will become light and variable after 03Z.

EQUIPMENT: KSDY obs are unavailable and will be AMD NOT SKED.


&&

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

$$

weather.gov/glasgow