Lewistown Muni, MT Climate: Temperature & Rain by Month
Explore NOAA NCEI's 1991–2020 climate normals → and a clearly labeled PlainClimate comfort calculation
30-year climate normals (1991-2020) from Lewistown Muni's primary NOAA station, LEWISTOWN MUNI AP.
The climate verdict for Lewistown Muni
Dryness leads the climate profile for Lewistown Muni, Montana, with 17.2 inches of precipitation a year. NOAA records an annual average of 43°F. At 40/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 6% of scores.
- 43°F
- yearly average temperature, NOAA normal
- 40/100
- comfort score, above 6% of station-mapped location scores
- 17.2"
- precipitation, annual total
- 121 days
- frost-free growing season
Lewistown Muni: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USW00024036 · Lewistown Muni, MT 43°F mean · 17.2" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 43°F
- RANK-COOL #823
- PHOTO-FINISH ≈ Rawlins
- PRCP-DRY 17.2"
- SWING-MID 42°F
- COMF-LOW 40/100
- LOAD-HEAT 8,177 HDD
- STN-1 USW00024036
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Rawlins Muni, WY (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every MT station list.
- Lewistown (this station) 43°F
- Hot Grafton, NH 43°F
- Near Rawlins, WY 43°F
- Near Saint Anthony, ID 43°F
- Near Hartford, ME 43°F
Lewistown Muni sits in Montana, the #6 coldest U.S. state at 43.4°F statewide annual average - see all 50 coldest states ranked by NOAA normals
Climate Living Index · Lewistown Muni
Lewistown Muni: 23/100 · grade F
Lewistown Muni publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals · NOAA hourly normals); 1 missing weight rescale to 100.
PlainClimate-derived for Lewistown Muni, not an official NOAA rating. Rankings still use Comfort Score 40/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Summer moisture balance | 43.6°F mean dew point | 53/100 · D |
| Precipitation balance | 17.2 in · 17.8 from 35 in | 36/100 · F |
| Annual temperature balance | 43.1°F · 24.4° from 67.5°F | 13/100 · F |
| Normal heat + freeze calendar | 201 calendar days | 13/100 · F |
| Frost-free season | 121 days/year | 7/100 · F |
Lewistown Muni · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Lewistown Muni is a continental Köppen climate: Dfb
Coldest-month mean 23.7°F and warmest-month mean 66.1°F place this station in continental, no dry season, warm summer climates (Dfb). Class Dfb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, no dry season, warm summer.
- Köppen code
- Dfb
- Group
- Continental
- Warmest month
- 66.1°F
- Coldest month
- 23.7°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Lewistown Muni sits across the climate record
Three NOAA fields for Lewistown Muni's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 88%
- Among 6,861 stations, Lewistown Muni sits in the cooler third of annual means.
- Annual precipitation
- Drier than 78%
- Lewistown Muni's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 46th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Lewistown Muni compares across U.S. station-mapped locations
Lewistown Muni's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
40 6th percentile score exceeds 6% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Lewistown Muni's measured station temperature trend
MethodologyAcross 102 complete annual observations from 1898 to 2025, LEWISTOWN MUNI AP warmed at a fitted rate of 0.14°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Lewistown Muni primary station fitted change +0.14 °C/decade
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|
| January | 34°F (1°C) | 13°F (-11°C) | 24°F (-5°C) | 0.6" | 29.0 | 0.0 |
| February | 35°F (2°C) | 14°F (-10°C) | 25°F (-4°C) | 0.5" | 26.1 | 0.0 |
| March | 44°F (7°C) | 21°F (-6°C) | 33°F (0°C) | 0.9" | 26.7 | 0.0 |
| April | 53°F (12°C) | 29°F (-2°C) | 41°F (5°C) | 1.7" | 20.5 | 0.0 |
| May | 63°F (17°C) | 37°F (3°C) | 50°F (10°C) | 2.9" | 7.8 | 0.0 |
| June | 71°F (22°C) | 45°F (7°C) | 58°F (14°C) | 3.4" | 0.3 | 0.5 |
| July | 82°F (28°C) | 51°F (10°C) | 66°F (19°C) | 1.8" | 0.0 | 5.7 |
| August | 81°F (27°C) | 50°F (10°C) | 65°F (19°C) | 1.7" | 0.0 | 5.0 |
| September | 70°F (21°C) | 42°F (5°C) | 56°F (13°C) | 1.4" | 2.7 | 1.3 |
| October | 56°F (13°C) | 31°F (-1°C) | 43°F (6°C) | 1.3" | 16.8 | 0.0 |
| November | 43°F (6°C) | 21°F (-6°C) | 32°F (0°C) | 0.7" | 25.2 | 0.0 |
| December | 35°F (2°C) | 14°F (-10°C) | 24°F (-4°C) | 0.5" | 29.3 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 84°F around July 28, short of 90°F on every date, while 201 dates carry a normal low at or below freezing, the coldest 12°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into April 30, then returns to freezing around October 13, covering 201 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is May 30, when 48% of years recorded at least a hundredth of an inch. The driest is December 7 at 22%. Summed across the calendar, that is about 116 wet dates a year.
The widest day
July 28 carries the biggest normal gap between afternoon and dawn, 32°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Lewistown Muni.
Where Lewistown Muni Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 201 nights a year, placing this among the most frost-prone tenth of ranked stations.
Lewistown Muni earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall
7.7 days with precipitation
8.2 days with precipitation
9.1 days with precipitation
11.7 days with precipitation
13.7 days with precipitation
13.6 days with precipitation
10.3 days with precipitation
9.0 days with precipitation
8.5 days with precipitation
9.4 days with precipitation
7.4 days with precipitation
7.3 days with precipitation
Lewistown Muni runs a summer-peaked wet season
40% of Lewistown Muni's yearly precipitation falls in June, July and August alone, against the 25% an evenly spread year would give those three months. The wettest month is June at 3.4", on a 42.4°F seasonal spread. Warm-season convection and, across the Southwest, the North American monsoon produce this shape: rain arrives in short heavy bursts during the hottest part of the year rather than as long cool-season soaking.
- Wettest three months: June, May, July, taking 47% of the annual total between them.
- Driest month: February at 0.5".
- Winter share: 9% falls in December, January and February.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A summer-peaked label means the June-August share reaches 35%; it describes timing across an average year, not any single season, and says nothing about how heavy an individual storm can be.
Lewistown Muni is dry, and what does fall arrives gently
Only about 116 days a year record measurable precipitation here, 32% of the calendar, and they carry 17.2" between them. At roughly 0.15 inches on an average wet day, this is not the damp drizzle of a marine climate; it is an arid record in which precipitation is both uncommon and light when it appears.
The wettest month by count is May at about 14 wet days; the driest is December at about 7.
A low per-event average in a dry record is a statement about typical days only. Arid regions can still take a large share of a year's total from a single convective storm, which a normal cannot show.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, not the extremes within it.
Frost Dates & Growing Season
First Fall Freeze
September 21
50% probability date
Last Spring Freeze
May 23
50% probability date
Growing Season
121 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
8,177
Higher = more heating needed
Cooling Degree Days
229
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Humidity & Wind
Monthly averages from hourly observations
| Month | Humidity | Wind (mph) | Clear Sky % | Overcast % |
|---|---|---|---|---|
| January | 66% | 10.0 | N/A | N/A |
| February | 65% | 9.3 | N/A | N/A |
| March | 59% | 9.7 | N/A | N/A |
| April | 56% | 9.8 | 32% | 21% |
| May | 61% | 9.0 | N/A | N/A |
| June | 56% | 7.7 | 67% | 14% |
| July | 47% | 7.6 | 70% | 3% |
| August | 47% | 7.6 | 69% | 10% |
| September | 54% | 8.4 | N/A | N/A |
| October | 57% | 10.1 | N/A | N/A |
| November | 61% | 10.3 | N/A | N/A |
| December | 65% | 9.8 | N/A | N/A |
Nationwide similar cities
Other rankable U.S. places outside MT closest to Lewistown Muni on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (43°F here).
- Almont, ND 43°F · 0.0°F off
- Bismarck, ND 43°F · 0.0°F off
- Clark, SD 43°F · 0.0°F off
- Grantsburg, WI 43°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (17.2" here), excluding temperature-peer places.
- Fleming, CO 17.2" · 0.0" off
- Long Creek, OR 17.2" · 0.0" off
- Newcastle, WY 17.2" · 0.0" off
- Colusa, CA 17.2" · 0.0" off
Data-derived climate profile
How Lewistown Muni's climate pattern fits together
heating led · dry · mid swing
Lewistown Muni's energy balance leans toward cold weather: 8,177 annual heating degree days against 229 for cooling. Its 42.4°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 121 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
July and January mark the typical warm and cold ends of the calendar in Lewistown Muni's middle-range seasonal profile. The measured spread is 42.4°F. The annual average is 43°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
Lewistown Muni's cold-season load does not imply a wet climate. Annual precipitation is 17.2 inches, which places the station in PlainClimate's dry range. Snowfall is not added to the interpretation because its annual value is missing. The snowfall and rainfall fields should be read separately rather than inferred from temperature.
These labels group NOAA 1991-2020 normals from Lewistown Muni's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Lewistown Muni, not an official NOAA class or a year-ahead forecast.
Questions about Lewistown Muni's climate
How much rain does Lewistown Muni get? ▼
How cold does Lewistown Muni get in winter? ▼
How much energy does heating and cooling require in Lewistown Muni? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Lewistown Muni's primary station: LEWISTOWN MUNI AP (USW00024036). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Lewistown Muni; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Lewistown Muni comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.