Shelby, MT Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Shelby's primary NOAA station, SHELBY.
The climate verdict for Shelby
Dryness leads the climate profile for Shelby, Montana, with 12.1 inches of precipitation a year. NOAA records an annual average of 42°F. At 39/100 (below average) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 4% of scores.
- 42°F
- annual average temperature (NOAA normal)
- 39/100
- comfort score, above 4% of station-mapped location scores
- 12.1"
- annual precipitation · 39" snow
- 116 days
- frost-free days per growing season
Shelby: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00247500 · Shelby, MT 42°F mean · 12.1" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 42°F
- RANK-COOL #617
- PHOTO-FINISH ≈ Dover-foxcroft…
- PRCP-DRY 12.1"
- SWING-WIDE 48°F
- COMF-LOW 39/100
- LOAD-HEAT 8,532 HDD
- STN-1 USC00247500
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Dover-foxcroft Wwtp, ME (+ 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.
- Shelby (this station) 42°F
- Cold Eden, VT 42°F
- Hot Dover-foxcroft…, ME 42°F
- Near Bethlehem, NH 42°F
- Near Fairfield Range…, ID 42°F
Shelby 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 · Shelby
Shelby: 14/100 · grade F
Shelby publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Shelby, not an official NOAA rating. Rankings still use Comfort Score 39/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 38.9 inches/year | 29/100 · F |
| Precipitation balance | 12.1 in · 22.9 from 35 in | 19/100 · F |
| Normal heat + freeze calendar | 202 calendar days | 13/100 · F |
| Annual temperature balance | 42.2°F · 25.3° from 67.5°F | 10/100 · F |
| Frost-free season | 116 days/year | 5/100 · F |
Shelby · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Shelby's normals sit in a dry climate class: BSk
Precipitation is low relative to temperature but above true desert thresholds: cold semi-arid steppe (BSk). Class BSk is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: dry (arid or semi-arid), specifically cold semi-arid steppe.
- Köppen code
- BSk
- Group
- Dry (arid or semi-arid)
- Warmest month
- 66.8°F
- Coldest month
- 18.8°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 Shelby sits across the climate record
Three NOAA fields for Shelby's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 91%
- Among 6,861 stations, Shelby sits in the cooler third of annual means.
- Annual precipitation
- Drier than 89%
- Shelby's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Wider than 73%
- Warmest-to-coldest month gap for Shelby is large versus 6,861 complete station-years.
How Shelby compares across U.S. station-mapped locations
Shelby's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
39 4th percentile score exceeds 4% 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%). This entry sits in this band.
- 40–50: 1,113 station-mapped locations (18%). Above this entry.
- 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
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 31°F (0°C) | 6°F (-14°C) | 19°F (-7°C) | 0.5" | 7.3" | 29.1 | 0.0 |
| February | 35°F (2°C) | 10°F (-12°C) | 23°F (-5°C) | 0.4" | 5.8" | 26.8 | 0.0 |
| March | 44°F (7°C) | 18°F (-8°C) | 31°F (0°C) | 0.6" | 6.9" | 27.8 | 0.0 |
| April | 54°F (12°C) | 28°F (-2°C) | 41°F (5°C) | 1.3" | 4.1" | 20.2 | 0.0 |
| May | 64°F (18°C) | 38°F (3°C) | 51°F (11°C) | 1.8" | 1.9" | 7.5 | 0.1 |
| June | 73°F (23°C) | 46°F (8°C) | 59°F (15°C) | 2.9" | 0.0" | 0.4 | 1.0 |
| July | 82°F (28°C) | 52°F (11°C) | 67°F (19°C) | 1.1" | 0.0" | 0.0 | 8.0 |
| August | 82°F (28°C) | 49°F (10°C) | 66°F (19°C) | 0.8" | 0.0" | 0.0 | 7.7 |
| September | 71°F (22°C) | 41°F (5°C) | 56°F (13°C) | 1.0" | 0.5" | 3.9 | 1.6 |
| October | 56°F (13°C) | 29°F (-2°C) | 43°F (6°C) | 0.7" | 1.4" | 19.0 | 0.0 |
| November | 42°F (6°C) | 18°F (-8°C) | 30°F (-1°C) | 0.5" | 5.5" | 25.7 | 0.0 |
| December | 33°F (1°C) | 9°F (-13°C) | 21°F (-6°C) | 0.5" | 5.5" | 29.4 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 85°F around July 30, short of 90°F on every date, while 202 dates carry a normal low at or below freezing, the coldest 5°F near January 5.
The freezing stretch
The normal low stays at or below 32°F into April 28, then returns to freezing around October 10, covering 202 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 June 6, when 38% of years recorded at least a hundredth of an inch. The driest is November 15 at 15%. Summed across the calendar, that is about 77 wet dates a year.
The widest day
August 17 carries the biggest normal gap between afternoon and dawn, 33°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Shelby.
Where Shelby Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 202 nights a year, placing this among the most frost-prone tenth of ranked stations.
A drier-than-most normal water year — around 12 inches, below what four out of five ranked stations collect.
Shelby earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 7.3"
5.1 days with precipitation
Snow: 5.8"
5.4 days with precipitation
Snow: 6.9"
6.0 days with precipitation
Snow: 4.1"
7.3 days with precipitation
Snow: 1.9"
9.3 days with precipitation
11.1 days with precipitation
5.8 days with precipitation
5.7 days with precipitation
Snow: 0.5"
6.1 days with precipitation
Snow: 1.4"
5.4 days with precipitation
Snow: 5.5"
4.6 days with precipitation
Snow: 5.5"
5.2 days with precipitation
Shelby runs a summer-peaked wet season
40% of Shelby'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 2.9", on a wide 48°F gap between its warmest and coldest month. 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, April, taking 49% of the annual total between them.
- Driest month: February at 0.4".
- Winter share: 11% 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.
Shelby is dry, and what does fall arrives gently
Only about 77 days a year record measurable precipitation here, 21% of the calendar, and they carry 12.1" between them. At roughly 0.16 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 June at about 11 wet days; the driest is November at about 5.
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.
Winter brings real snow to Shelby
Shelby averages 38.9 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 21 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 38.9 inches of depth.
- Days recording measurable snow: about 21 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 32% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
September 16
50% probability date
Last Spring Freeze
May 23
50% probability date
Growing Season
116 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
8,532
Higher = more heating needed
Cooling Degree Days
242
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside MT closest to Shelby 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 (42°F here).
- Altamont, UT 42°F · 0.0°F off
- Carson, ND 42°F · 0.0°F off
- Chama, NM 42°F · 0.0°F off
- Driggs, ID 42°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (12.1" here), excluding temperature-peer places.
- Crane, TX 12.1" · 0.0" off
- Evanston, WY 12.1" · 0.0" off
- Hachita, NM 12.1" · 0.0" off
- Lindsay, CA 12.1" · 0.0" off
Snow and freeze rhythm
When cold and snow define Shelby
heating led · dry · mid swing
Shelby's energy balance leans toward cold weather: 8,532 annual heating degree days against 242 for cooling. Its 48.0°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 116 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.
-
1. Shelby coldest normal
January
Averaging 19°F (-7°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Shelby typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Shelby snow peak
January
Shelby averages 38.9 inches of snow a year, with January the snowiest month on the normals.
Questions about Shelby's climate
How much snow does Shelby get? ▼
How cold does Shelby get in winter? ▼
How much energy does heating and cooling require in Shelby? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Shelby's primary station: SHELBY (USC00247500). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as an incorporated place (GEOID 3067450). Match rule for Shelby: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Shelby 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.