Climate Comfort Score
44/100
Moderate
NOAA 1991–2020 normals 45°F annual avg Public-domain federal data
Hamilton, MT Climate
Explore average temperature, rainfall, and comfort score sourced from NOAA NCEI's 1991–2020 climate normals →
- 45°F
- Avg annual temp
- 44/100
- Comfort score
- 13.6"
- Annual precip
- 124d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Hamilton
Hamilton, Montana averages 45°F a year and scores 44/100 on the comfort index - moderate, milder than 8% of U.S. cities.
- 45°F
- average temperature, NOAA 1991-2020 normal
- 44/100
- comfort score, milder than 8% of U.S. cities
- 13.6"
- yearly precipitation total
- 124 days
- growing season, frost-free days
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
45°F (7°C)
Avg High
57°F
Avg Low
32°F
Annual Precip
13.6"
Comfort Score
44/100
Moderate
Avg Annual Temperature
45°F
30-year mean (NOAA NCEI)
Annual Precipitation
13.6"
Liquid-equivalent total
Comfort score vs national 100-point ceiling (Hamilton) 44.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Hamilton area.
How Hamilton compares to every U.S. city
Hamilton's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
44 Top 92% higher than 8% 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 Hamilton
MethodologyZooming out from Hamilton's own normal, the chart below shows how the U.S. land temperature anomaly has tracked the global mean since 1900 - the most recent decade sits warmer than the 30-year mean shown here.
- 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 | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 35°F (2°C) | 19°F (-7°C) | 27°F (-3°C) | 1.0" | 27.7 | 0.0 |
| February | 39°F (4°C) | 20°F (-7°C) | 29°F (-1°C) | 1.2" | 25.9 | 0.0 |
| March | 49°F (9°C) | 25°F (-4°C) | 37°F (3°C) | 1.0" | 25.7 | 0.0 |
| April | 56°F (13°C) | 31°F (-1°C) | 43°F (6°C) | 1.1" | 16.1 | 0.0 |
| May | 66°F (19°C) | 38°F (3°C) | 52°F (11°C) | 1.5" | 4.9 | 0.3 |
| June | 73°F (23°C) | 45°F (7°C) | 59°F (15°C) | 1.6" | 0.2 | 1.8 |
| July | 84°F (29°C) | 50°F (10°C) | 67°F (19°C) | 0.8" | 0.0 | 10.5 |
| August | 82°F (28°C) | 48°F (9°C) | 65°F (18°C) | 0.8" | 0.0 | 8.8 |
| September | 72°F (22°C) | 40°F (5°C) | 56°F (13°C) | 0.8" | 2.1 | 1.0 |
| October | 57°F (14°C) | 31°F (-1°C) | 44°F (7°C) | 0.9" | 16.5 | 0.0 |
| November | 43°F (6°C) | 23°F (-5°C) | 33°F (0°C) | 1.4" | 25.0 | 0.0 |
| December | 34°F (1°C) | 18°F (-8°C) | 26°F (-4°C) | 1.3" | 28.3 | 0.0 |
Monthly Precipitation
Average monthly rainfall
January 1.0"
9.2 days with precipitation
February 1.2"
8.7 days with precipitation
March 1.0"
10.3 days with precipitation
April 1.1"
9.4 days with precipitation
May 1.5"
10.7 days with precipitation
June 1.6"
9.7 days with precipitation
July 0.8"
6.6 days with precipitation
August 0.8"
7.0 days with precipitation
September 0.8"
6.3 days with precipitation
October 0.9"
8.7 days with precipitation
November 1.4"
10.1 days with precipitation
December 1.3"
10.4 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
September 22
50% probability date
Last Spring Freeze
May 21
50% probability date
Growing Season
124 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,551
Higher = more heating needed
Cooling Degree Days
216
Higher = more cooling needed
Warmest Month
July
Coldest Month
December
What Hamilton's climate means for you
Hamilton runs 45°F a year - peaking in July, coldest in December.
- Gardeners get about 124 frost-free days, with the last spring freeze near May 21 - plan the planting calendar around it, not the regional average.
- Energy bills track 7,551 heating and 216 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: Hamilton, MT
In Hamilton, Montana, the NOAA 1991–2020 climate normals put the annual average temperature at 45°F, ranging from a mean daily high of 57°F to a mean daily low of 32°F. July is typically the warmest month of the year, while December is the coldest. As thirty-year averages computed from station USC00243885, these numbers smooth out year-to-year noise into a working baseline for a typical month.
Hamilton averages 13.6 inches of precipitation a year, predominantly as rainfall, and that matters as much to daily life here as temperature does. 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 21 and the first fall freeze near September 22. As for energy demand, 7,551 heating degree days and 216 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Hamilton scores 44/100 (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 December-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 Hamilton, MT? ▼
The average annual temperature in Hamilton, Montana is 45°F. The warmest month averages 84°F (29°C) and the coldest averages 18°F (-8°C).
How much rain does Hamilton get? ▼
Hamilton receives 13.6 inches of precipitation annually. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Hamilton? ▼
Hamilton has a climate comfort score of 44/100 (Moderate), milder than 8% of U.S. cities in the PlainClimate database.
When is the growing season in Hamilton? ▼
Hamilton has approximately 124 frost-free days per year, with the last spring freeze around May 21 and the first fall freeze around September 22.
How much energy does heating and cooling require in Hamilton? ▼
Hamilton has 7,551 heating degree days and 216 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 Hamilton climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00243885 near Hamilton.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00243885. 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.