Libby Dam, 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 Libby Dam's primary NOAA station, LIBBY DAM (BASE).
The climate verdict for Libby Dam
Dryness leads the climate profile for Libby Dam, Montana, with 17.1 inches of precipitation a year. NOAA records an annual average of 46°F. At 52/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 24% of scores.
- 46°F
- yearly average temperature, NOAA normal
- 52/100
- comfort score, above 24% of station-mapped location scores
- 17.1"
- annual precipitation
- 143 days
- frost-free growing season
Libby Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00245011 · Libby Dam, MT 46°F mean · 17.1" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 46°F
- RANK-COOL #1,715
- PHOTO-FINISH ≈ Northport
- PRCP-DRY 17.1"
- SWING-MID 40°F
- COMF-LOW 52/100
- LOAD-HEAT 7,046 HDD
- STN-1 USC00245011
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Northport, WA (+ 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.
- Libby Dam (this station) 46°F
- Cold Lindrith, NM 46°F
- Hot Durango La Plat…, CO 46°F
- Near Northport, WA 46°F
- Near Chewelah, WA 46°F
Libby Dam 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 · Libby Dam
Libby Dam: 26/100 · grade F
Libby Dam publishes 4 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 2 missing weights rescale to 100.
PlainClimate-derived for Libby Dam, not an official NOAA rating. Rankings still use Comfort Score 52/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 17.1 in · 17.9 from 35 in | 36/100 · F |
| Annual temperature balance | 46.4°F · 21.1° from 67.5°F | 25/100 · F |
| Normal heat + freeze calendar | 183 calendar days | 23/100 · F |
| Frost-free season | 143 days/year | 20/100 · F |
Libby Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Libby Dam is a continental Köppen climate: Dfb
Coldest-month mean 28.1°F and warmest-month mean 67.8°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
- 67.8°F
- Coldest month
- 28.1°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 Libby Dam sits across the climate record
Three NOAA fields for Libby Dam's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 75%
- Among 6,861 stations, Libby Dam sits in the cooler third of annual means.
- Annual precipitation
- Drier than 78%
- Libby Dam's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 34th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Libby Dam compares across U.S. station-mapped locations
Libby Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
52 24th percentile score exceeds 24% 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%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). This entry sits in this band.
- 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
Libby Dam's measured station temperature trend
MethodologyAcross 31 complete annual observations from 1989 to 2025, LIBBY DAM (BASE) warmed at a fitted rate of 0.30°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Libby Dam primary station fitted change +0.30 °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 | 35°F (1°C) | 22°F (-6°C) | 28°F (-2°C) | 1.5" | 29.8 | 0.0 |
| February | 40°F (4°C) | 22°F (-6°C) | 31°F (-1°C) | 1.1" | 26.5 | 0.0 |
| March | 49°F (9°C) | 26°F (-3°C) | 37°F (3°C) | 1.1" | 27.6 | 0.0 |
| April | 58°F (14°C) | 32°F (0°C) | 45°F (7°C) | 1.2" | 19.2 | 0.0 |
| May | 68°F (20°C) | 39°F (4°C) | 54°F (12°C) | 1.8" | 6.2 | 0.3 |
| June | 75°F (24°C) | 46°F (8°C) | 60°F (16°C) | 2.4" | 0.2 | 1.7 |
| July | 85°F (30°C) | 50°F (10°C) | 68°F (20°C) | 0.8" | 0.1 | 10.6 |
| August | 85°F (30°C) | 49°F (10°C) | 67°F (20°C) | 0.7" | 0.0 | 10.4 |
| September | 74°F (23°C) | 42°F (6°C) | 58°F (14°C) | 1.1" | 2.0 | 1.4 |
| October | 57°F (14°C) | 34°F (1°C) | 45°F (7°C) | 1.7" | 13.9 | 0.0 |
| November | 42°F (6°C) | 28°F (-2°C) | 35°F (2°C) | 1.8" | 23.5 | 0.0 |
| December | 34°F (1°C) | 23°F (-5°C) | 28°F (-2°C) | 1.7" | 28.8 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 89°F around July 30, short of 90°F on every date, while 183 dates carry a normal low at or below freezing, the coldest 21°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into April 20, then returns to freezing around October 21, covering 183 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 November 23, when 48% of years recorded at least a hundredth of an inch. The driest is July 31 at 17%. Summed across the calendar, that is about 132 wet dates a year.
The widest day
August 1 carries the biggest normal gap between afternoon and dawn, 37°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Libby Dam.
Where Libby Dam Stands Nationally
Day-to-night contrast is extreme by national standards — the widest normal daily swing reaches about 37°F, sharper than nine in ten ranked stations see.
Freezing is routine here by normals standards — the normal low reaches 32°F or colder on about 183 nights a year, more than most ranked stations.
Libby Dam earns 2 nationally notable standings (outer quintiles) against 6,860 NOAA 1991–2020 normals stations; only those extremes render.
Monthly Precipitation
Average monthly rainfall
14.3 days with precipitation
10.6 days with precipitation
11.4 days with precipitation
10.8 days with precipitation
12.1 days with precipitation
12.2 days with precipitation
6.1 days with precipitation
5.4 days with precipitation
8.4 days with precipitation
11.7 days with precipitation
14.4 days with precipitation
14.6 days with precipitation
Libby Dam spreads its precipitation across the year
Neither half of the year dominates here: June through August take 23% of the annual total and December through February 26%, with neither reaching the 35% that would mark a distinct wet season. Libby Dam has no dry season to plan around, though it does carry a 39.7°F seasonal spread.
The gap between the wettest and driest month still matters: June averages 2.4" and August 0.7". The three wettest months together take 35% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
Rain reaches Libby Dam in small, frequent amounts
Libby Dam records about 132 days with measurable precipitation a year and 17.1" in total, which works out to roughly 0.13 inches on an average wet day. Precipitation on 36% of all days, arriving that lightly, is the damp many-grey-days pattern rather than the storm-driven one.
Places in this band read as wetter than their annual totals suggest, because what people notice is the number of overcast days, not the depth in the gauge.
- Most wet days: December, about 15 of them.
- Fewest: August, about 5.
- Average depth per wet day: 0.13 inches.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year and say nothing about the heaviest single storm on record.
Frost Dates & Growing Season
First Fall Freeze
October 1
50% probability date
Last Spring Freeze
May 11
50% probability date
Growing Season
143 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,046
Higher = more heating needed
Cooling Degree Days
292
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside MT closest to Libby Dam 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 (46°F here).
- Bad Axe, MI 46°F · 0.0°F off
- Bickleton, WA 46°F · 0.0°F off
- Bridgewater, SD 46°F · 0.0°F off
- Camp Crook, SD 46°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (17.1" here), excluding temperature-peer places.
- Springer, NM 17.1" · 0.0" off
- St John, WA 17.1" · 0.0" off
- Morgan, UT 17.1" · 0.0" off
- Stratford, TX 17.1" · 0.0" off
Data-derived climate profile
How Libby Dam's climate pattern fits together
heating led · dry · mid swing
Libby Dam's energy balance leans toward cold weather: 7,046 annual heating degree days against 292 for cooling. Its 39.7°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 143 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 Libby Dam's middle-range seasonal profile. The measured spread is 39.7°F. The annual average is 46°F. Neither the annual mean nor one extreme month represents the full calendar on its own.
Libby Dam's cold-season load does not imply a wet climate. Annual precipitation is 17.1 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 Libby Dam'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 Libby Dam, not an official NOAA class or a year-ahead forecast.
Questions about Libby Dam's climate
How much rain does Libby Dam get? ▼
How cold does Libby Dam get in winter? ▼
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Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Libby Dam's primary station: LIBBY DAM (BASE) (USC00245011). 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 Libby Dam; 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 Libby Dam 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.