As of 06:53 MDT

Weather in Grannis, MT

40°Current weather

Grannis, Thursday, 8 October, 06:53

Clear. Feels like 31°. High 77°, low 40°.

Pressure30.09 inHg
Wind17.3 mph NW
Humidity52%
Visibility6.2 mi
Dew point25°

Monthly outlook for Grannis, MT: average high 54.1°, average low 34.7°. That is 0.4° above the climate normal for October. Precipitation is expected on 7 days (about 2.2 inches), against a normal of 4 days and 1.0 inches. The warmest day looks like 9 October (81.8°), the coolest 13 October (26.6°).

54.1°/34.7°
Average high / low
+0.4°
Above normal
7 / 4
Wet days / normal
2.2 in
Precipitation this month

Ten-day blocks vs climate normal

PeriodForecast highNormalDifference
8 October – 17 October53°54°-0.6°
18 October – 27 October56.1°51.2°+2.7°
28 October – 6 Novemberat normal44.3°—

October records over 66 years

83.1°1 October 2011All-time high
-12.3°10 October 2009All-time low

Climate normals and records are computed from the nearest reference point — Clyde Park (10 mi).

Fri, 0982° / 40°0Partly cloudy
82 °Partly cloudy

Grannis, Friday, 9 October

Partly cloudy. High 82°, low 40°.

Pressure29.59 inHg
Wind9.8 mph S
Humidity20%
Visibility6.2 mi
Dew point27°
Sat, 1060° / 42°0.21Rain
60 °Rain

Grannis, Saturday, 10 October

Rain. High 60°, low 42°.

Pressure29.53 inHg
Wind11.6 mph SE
Humidity36%
Visibility6.2 mi
Dew point33°
Sun, 1140° / 33°0.44Snow
40 °Snow

Grannis, Sunday, 11 October

Snow. High 40°, low 33°.

Pressure30.03 inHg
Wind9.9 mph SE
Humidity86%
Visibility2.7 mi
Dew point30°
Mon, 1232° / 28°0.51Snow
32 °Snow

Grannis, Monday, 12 October

Snow. High 32°, low 28°.

Pressure30.15 inHg
Wind8.8 mph SE
Humidity98%
Visibility—
Dew point31°
Tue, 1341° / 27°0Mostly clear
41 °Mostly clear

Grannis, Tuesday, 13 October

Mostly clear. High 41°, low 27°.

Pressure30.03 inHg
Wind4.5 mph SW
Humidity88%
Visibility—
Dew point30°
Wed, 1459° / 38°0.03Snow
59 °Snow

Grannis, Wednesday, 14 October

Snow. High 59°, low 38°.

Pressure29.35 inHg
Wind16 mph SW
Humidity43%
Visibility—
Dew point35°
Thu, 1536° / 33°0.44Snow
36 °Snow

Grannis, Thursday, 15 October

Snow. High 36°, low 33°.

Pressure30.21 inHg
Wind10.4 mph W
Humidity83%
Visibility—
Dew point30°
Fri, 1647° / 27°0Clear
47 °Clear

Grannis, Friday, 16 October

Clear. High 47°, low 27°.

Pressure30.39 inHg
Wind6.4 mph W
Humidity64%
Visibility—
Dew point28°
Sat, 1755° / 31°0Clear
55 °Clear

Grannis, Saturday, 17 October

Clear. High 55°, low 31°.

Pressure30.12 inHg
Wind9.3 mph W
Humidity46%
Visibility—
Dew point28°
Sun, 1861° / 33°0Mostly clear
61 °Mostly clear

Grannis, Sunday, 18 October

Mostly clear. High 61°, low 33°.

Pressure30.12 inHg
Wind6.7 mph W
Humidity45%
Visibility—
Dew point28°
Mon, 1961° / 38°0Partly cloudy
61 °Partly cloudy

Grannis, Monday, 19 October

Partly cloudy. High 61°, low 38°.

Pressure30.09 inHg
Wind7.8 mph SW
Humidity35%
Visibility—
Dew point27°
Tue, 2065° / 38°0Partly cloudy
65 °Partly cloudy

Grannis, Tuesday, 20 October

Partly cloudy. High 65°, low 38°.

Pressure30.03 inHg
Wind9.8 mph SW
Humidity30%
Visibility—
Dew point25°
Wed, 2158° / 43°0.11Light rain
58 °Light rain

Grannis, Wednesday, 21 October

Light rain. High 58°, low 43°.

Pressure29.41 inHg
Wind24.5 mph W
Humidity30%
Visibility—
Dew point25°
Thu, 2244° / 35°0.06Light rain
44 °Light rain

Grannis, Thursday, 22 October

Light rain. High 44°, low 35°.

Pressure29.53 inHg
Wind27 mph W
Humidity52%
Visibility—
Dew point25°
Fri, 2348° / 30°0.41Snow
48 °Snow

Grannis, Friday, 23 October

Snow. High 48°, low 30°.

Pressure29.65 inHg
Wind13.4 mph W
Humidity63%
Visibility—
Dew point30°
From day 17 onward the outlook is built from 60-year climate statistics
Sat, 2450° / 31°0.04Climate normal
50 °Climate normal

Grannis, Saturday, 24 October

Climate normal for this date — 60-year average.

Average high50°
Average low31°
Average precipitation0.04 in
Chance of precipitation28%
Record high65° (1992)
Record low8° (2020)
Sun, 2550° / 31°0.04Climate normal
50 °Climate normal

Grannis, Sunday, 25 October

Climate normal for this date — 60-year average.

Average high50°
Average low31°
Average precipitation0.04 in
Chance of precipitation22%
Record high68° (2014)
Record low0° (2020)
Mon, 2649° / 31°0.07Climate normal
49 °Climate normal

Grannis, Monday, 26 October

Climate normal for this date — 60-year average.

Average high49°
Average low31°
Average precipitation0.07 in
Chance of precipitation35%
Record high65° (1999)
Record low-4° (2020)
Tue, 2748° / 29°0.04Climate normal
48 °Climate normal

Grannis, Tuesday, 27 October

Climate normal for this date — 60-year average.

Average high48°
Average low29°
Average precipitation0.04 in
Chance of precipitation25%
Record high68° (2024)
Record low2° (2019)
Wed, 2847° / 29°0.06Climate normal
47 °Climate normal

Grannis, Wednesday, 28 October

Climate normal for this date — 60-year average.

Average high47°
Average low29°
Average precipitation0.06 in
Chance of precipitation27%
Record high65° (1987)
Record low4° (1971)
Thu, 2945° / 28°0.06Climate normal
45 °Climate normal

Grannis, Thursday, 29 October

Climate normal for this date — 60-year average.

Average high45°
Average low28°
Average precipitation0.06 in
Chance of precipitation28%
Record high65° (1987)
Record low-8° (2019)
Fri, 3045° / 27°0.04Climate normal
45 °Climate normal

Grannis, Friday, 30 October

Climate normal for this date — 60-year average.

Average high45°
Average low27°
Average precipitation0.04 in
Chance of precipitation25%
Record high66° (1987)
Record low-10° (1972)
Sat, 3144° / 26°0.06Climate normal
44 °Climate normal

Grannis, Saturday, 31 October

Climate normal for this date — 60-year average.

Average high44°
Average low26°
Average precipitation0.06 in
Chance of precipitation27%
Record high64° (2014)
Record low-12° (2002)
Sun, 0144° / 26°0.06Climate normal
44 °Climate normal

Grannis, Sunday, 1 November

Climate normal for this date — 60-year average.

Average high44°
Average low26°
Average precipitation0.06 in
Chance of precipitation25%
Record high67° (2025)
Record low-3° (1989)
Mon, 0243° / 26°0.03Climate normal
43 °Climate normal

Grannis, Monday, 2 November

Climate normal for this date — 60-year average.

Average high43°
Average low26°
Average precipitation0.03 in
Chance of precipitation25%
Record high61° (2020)
Record low-10° (1995)
Tue, 0344° / 27°0.04Climate normal
44 °Climate normal

Grannis, Tuesday, 3 November

Climate normal for this date — 60-year average.

Average high44°
Average low27°
Average precipitation0.04 in
Chance of precipitation22%
Record high63° (2020)
Record low-1° (1995)
Wed, 0444° / 27°0.05Climate normal
44 °Climate normal

Grannis, Wednesday, 4 November

Climate normal for this date — 60-year average.

Average high44°
Average low27°
Average precipitation0.05 in
Chance of precipitation30%
Record high61° (2020)
Record low-6° (1973)
Thu, 0544° / 27°0.06Climate normal
44 °Climate normal

Grannis, Thursday, 5 November

Climate normal for this date — 60-year average.

Average high44°
Average low27°
Average precipitation0.06 in
Chance of precipitation38%
Record high66° (2020)
Record low-5° (2003)
Fri, 0643° / 26°0.05Climate normal
43 °Climate normal

Grannis, Friday, 6 November

Climate normal for this date — 60-year average.

Average high43°
Average low26°
Average precipitation0.05 in
Chance of precipitation27%
Record high62° (1999)
Record low2° (2003)

About the monthly outlook

How accurate is a 30-day forecast?

The first 16 days come from weather models — reliable for the first 3–5 days and progressively less so after that. Days 17 through 30 for Grannis, MT are built from the climate normal, the 60-year average, so they show typical weather for those dates rather than a specific forecast.

What does "above normal" mean?

We compare the forecast against the climate normal for those exact calendar days, computed from 60 years of observations. The deviation shows how much the coming month differs from a typical one.

Where do the 66-year records come from?

They are real temperature extremes recorded in Grannis, MT since 1960: the highest and lowest reading for each calendar date, with the year it happened.

How often is it updated?

The forecast portion refreshes every hour; the climate portion is based on long-term data and stays stable.