Climate Comfort Score
49/100
Moderate
NOAA 1991–2020 normals 47°F annual avg 2 stations
Roundup, MT Climate
Average temperature, precipitation, and a comfort score, drawn from NOAA NCEI 1991–2020 normals →
- 47°F
- Avg annual temp
- 49/100
- Comfort score
- 14.9"
- Annual precip
- 124d
- Growing season
30-year climate normals from 2 weather stations (1991-2020).
The climate verdict for Roundup
Roundup, Montana averages 47°F a year and scores 49/100 on the comfort index - moderate, milder than 18% of U.S. cities.
- 47°F
- yearly average temperature, NOAA normal
- 49/100
- comfort score, milder than 18% of U.S. cities
- 14.9"
- annual precipitation · 24" snow
- 124 days
- frost-free days per growing season
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
47°F (8°C)
Avg High
61°F
Avg Low
32°F
Annual Precip
14.9"
Annual Snow
24.4"
Comfort Score
49/100
Moderate
Avg Annual Temperature
47°F
30-year mean (NOAA NCEI)
Annual Precipitation
14.9"
Plus 24.4" of snow
Comfort score vs national 100-point ceiling (Roundup) 49.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Roundup area.
How Roundup compares to every U.S. city
Roundup's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
49 Top 82% higher than 18% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Roundup
MethodologySince 1900, U.S. land temperatures have tracked (and diverged from) the global mean - the chart below shows how. Roundup's current NOAA 1991-2020 normal sits within that longer spread, and the most recent decade runs warmer than the 30-year mean.
- United States land mean (NOAA NCEI) +0.11 °C/decade
- Global anomaly (NASA GISTEMP) +0.11 °C/decade
- Paris Agreement thresholds 1.5°C / 2.0°C
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 37°F (3°C) | 13°F (-10°C) | 25°F (-4°C) | 0.4" | 5.2" | 27.4 | 0.0 |
| February | 41°F (5°C) | 15°F (-9°C) | 28°F (-2°C) | 0.4" | 3.9" | 25.2 | 0.0 |
| March | 51°F (10°C) | 22°F (-5°C) | 36°F (2°C) | 0.7" | 4.4" | 24.5 | 0.0 |
| April | 60°F (16°C) | 30°F (-1°C) | 45°F (7°C) | 1.7" | 1.4" | 15.4 | 0.0 |
| May | 69°F (21°C) | 39°F (4°C) | 54°F (12°C) | 2.5" | 0.1" | 3.9 | 0.8 |
| June | 78°F (26°C) | 48°F (9°C) | 63°F (17°C) | 2.9" | 0.0" | 0.1 | 4.4 |
| July | 89°F (32°C) | 54°F (12°C) | 71°F (22°C) | 1.7" | 0.0" | 0.0 | 17.6 |
| August | 88°F (31°C) | 51°F (11°C) | 70°F (21°C) | 1.2" | 0.0" | 0.1 | 15.7 |
| September | 77°F (25°C) | 42°F (6°C) | 60°F (15°C) | 1.2" | 0.0" | 1.6 | 4.9 |
| October | 61°F (16°C) | 32°F (0°C) | 46°F (8°C) | 1.2" | 1.0" | 12.2 | 0.1 |
| November | 47°F (8°C) | 22°F (-6°C) | 34°F (1°C) | 0.5" | 2.8" | 23.8 | 0.0 |
| December | 37°F (3°C) | 14°F (-10°C) | 26°F (-4°C) | 0.4" | 5.6" | 28.7 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 0.4"
Snow: 5.2"
4.0 days with precipitation
February 0.4"
Snow: 3.9"
3.6 days with precipitation
March 0.7"
Snow: 4.4"
5.1 days with precipitation
April 1.7"
Snow: 1.4"
7.7 days with precipitation
May 2.5"
Snow: 0.1"
10.0 days with precipitation
June 2.9"
10.6 days with precipitation
July 1.7"
7.0 days with precipitation
August 1.2"
5.1 days with precipitation
September 1.2"
5.3 days with precipitation
October 1.2"
Snow: 1.0"
6.9 days with precipitation
November 0.5"
Snow: 2.8"
3.9 days with precipitation
December 0.4"
Snow: 5.6"
4.5 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
September 21
50% probability date
Last Spring Freeze
May 20
50% probability date
Growing Season
124 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,193
Higher = more heating needed
Cooling Degree Days
482
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
What Roundup's climate means for you
Roundup runs 47°F a year - peaking in July, coldest in January.
- Gardeners get about 124 frost-free days, with the last spring freeze near May 20 - plan the planting calendar around it, not the regional average.
- Energy bills track 7,193 heating and 482 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Roundup, MT
Roundup, Montana runs an annual average of 47°F, ranging from a mean daily high of 61°F to a mean daily low of 32°F, per NOAA's 1991–2020 climate normals. July is typically the warmest month of the year, while January is the coldest. Drawn from 2 weather stations, these thirty-year averages smooth out year-to-year swings into a baseline for what a typical month looks like here.
Anyone planning to live, garden, or travel in Roundup should weigh precipitation alongside temperature: the annual average runs 14.9 inches, with 24.4 inches typically falling as snow. The frost-free season averages 124 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near May 20 and the first fall freeze near September 21. And on the energy front, 7,193 heating degree days and 482 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Roundup scores 49/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. The monthly tables above are the practical planning tool: mild highs and lows land in the shoulder seasons, July-driven heat peaks in summer, and January-driven cold sets in over deep winter. These are thirty-year averages, not a forecast - any single year can run warmer, wetter, drier, or cooler than the normal.
Frequently Asked Questions
What is the average temperature in Roundup, MT? ▼
The average annual temperature in Roundup, Montana is 47°F. The warmest month averages 89°F (32°C) and the coldest averages 13°F (-10°C).
How much rain does Roundup get? ▼
Roundup receives 14.9 inches of precipitation annually, including 24.4 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Roundup? ▼
Roundup has a climate comfort score of 49/100 (Moderate), milder than 18% of U.S. cities in the PlainClimate database.
When is the growing season in Roundup? ▼
Roundup has approximately 124 frost-free days per year, with the last spring freeze around May 20 and the first fall freeze around September 21.
How much energy does heating and cooling require in Roundup? ▼
Roundup has 7,193 heating degree days and 482 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Roundup climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from 2 weather stations near Roundup.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00247214. For informational purposes only.
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.