Holter Dam, MT Climate: Temperature & Rain by Month
Pulled from NOAA NCEI 1991–2020 normals →: climate measurements used in PlainClimate's documented score
30-year climate normals (1991-2020) from Holter Dam's primary NOAA station, HOLTER DAM.
The climate verdict for Holter Dam
Dryness leads the climate profile for Holter Dam, Montana, with 13.8 inches of precipitation a year. NOAA records an annual average of 47°F. At 49/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 18% of scores.
- 47°F
- yearly average temperature, NOAA normal
- 49/100
- comfort score, above 18% of station-mapped location scores
- 13.8"
- annual precipitation · 28" snow
- 128 days
- frost-free growing season
Holter Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00244241 · Holter Dam, MT 47°F mean · 13.8" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 47°F
- RANK-COOL #1,784
- PHOTO-FINISH ≈ Garden Valley
- PRCP-DRY 13.8"
- SWING-MID 40°F
- COMF-LOW 49/100
- LOAD-HEAT 6,912 HDD
- STN-1 USC00244241
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Garden Valley, ID (+ 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.
- Holter Dam (this station) 47°F
- Cold Kellogg, ID 47°F
- Hot Monticello, UT 47°F
- Near Garden Valley, ID 47°F
- Near Troy, MT 47°F
Holter 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 · Holter Dam
Holter Dam: 28/100 · grade F
Holter Dam publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Holter Dam, not an official NOAA rating. Rankings still use Comfort Score 49/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 28.0 inches/year | 40/100 · D |
| Normal heat + freeze calendar | 168 calendar days | 34/100 · F |
| Annual temperature balance | 46.8°F · 20.7° from 67.5°F | 26/100 · F |
| Precipitation balance | 13.8 in · 21.2 from 35 in | 24/100 · F |
| Frost-free season | 128 days/year | 11/100 · F |
Holter Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Holter Dam'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
- 68.3°F
- Coldest month
- 28.3°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 Holter Dam sits across the climate record
Three NOAA fields for Holter 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 74%
- Among 6,861 stations, Holter Dam sits in the cooler third of annual means.
- Annual precipitation
- Drier than 86%
- Holter Dam's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 36th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Holter Dam compares across U.S. station-mapped locations
Holter Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
49 18th percentile score exceeds 18% 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
Holter Dam's measured station temperature trend
MethodologyAcross 95 complete annual observations from 1904 to 2025, HOLTER DAM warmed at a fitted rate of 0.11°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Holter Dam primary station fitted change +0.11 °C/decade
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) | 20°F (-7°C) | 28°F (-2°C) | 0.3" | 6.9" | 23.0 | 0.0 |
| February | 40°F (4°C) | 20°F (-7°C) | 30°F (-1°C) | 0.4" | 5.4" | 21.5 | 0.0 |
| March | 49°F (9°C) | 26°F (-3°C) | 37°F (3°C) | 0.6" | 2.7" | 21.1 | 0.0 |
| April | 57°F (14°C) | 32°F (0°C) | 45°F (7°C) | 1.5" | 2.2" | 14.5 | 0.0 |
| May | 67°F (19°C) | 39°F (4°C) | 53°F (12°C) | 2.6" | 0.1" | 5.0 | 0.2 |
| June | 75°F (24°C) | 46°F (8°C) | 61°F (16°C) | 2.9" | 0.2" | 0.2 | 1.9 |
| July | 85°F (30°C) | 51°F (11°C) | 68°F (20°C) | 1.0" | 0.0" | 0.0 | 12.6 |
| August | 85°F (29°C) | 50°F (10°C) | 67°F (20°C) | 1.2" | 0.0" | 0.0 | 11.6 |
| September | 74°F (23°C) | 44°F (6°C) | 59°F (15°C) | 1.3" | 0.0" | 1.9 | 2.2 |
| October | 59°F (15°C) | 36°F (2°C) | 48°F (9°C) | 1.0" | 0.9" | 9.6 | 0.0 |
| November | 45°F (7°C) | 28°F (-2°C) | 37°F (3°C) | 0.5" | 3.4" | 16.6 | 0.0 |
| December | 37°F (3°C) | 22°F (-6°C) | 29°F (-2°C) | 0.5" | 6.2" | 22.7 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 88°F around July 27, short of 90°F on every date, while 168 dates carry a normal low at or below freezing, the coldest 19°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into April 16, then returns to freezing around November 1, covering 168 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 29, when 38% of years recorded at least a hundredth of an inch. The driest is December 4 at 16%. Summed across the calendar, that is about 86 wet dates a year.
The widest day
July 27 carries the biggest normal gap between afternoon and dawn, 36°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Holter Dam.
Where Holter Dam Stands Nationally
A drier-than-most normal water year — around 14 inches, below what four out of five ranked stations collect.
Daily temperature swings run wider than most of the country, peaking near 36°F between the normal high and low.
Holter 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 and snowfall
Snow: 6.9"
5.5 days with precipitation
Snow: 5.4"
5.9 days with precipitation
Snow: 2.7"
6.3 days with precipitation
Snow: 2.2"
9.3 days with precipitation
Snow: 0.1"
11.0 days with precipitation
Snow: 0.2"
10.2 days with precipitation
6.4 days with precipitation
6.9 days with precipitation
6.5 days with precipitation
Snow: 0.9"
6.9 days with precipitation
Snow: 3.4"
5.4 days with precipitation
Snow: 6.2"
5.1 days with precipitation
Holter Dam runs a summer-peaked wet season
37% of Holter Dam'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 40°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, April, taking 51% of the annual total between them.
- Driest month: January at 0.3".
- Winter share: 8% 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.
Holter Dam is dry, and what does fall arrives gently
Only about 85 days a year record measurable precipitation here, 23% of the calendar, and they carry 13.8" 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 May at about 11 wet days; the driest is December 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 Holter Dam
Holter Dam averages 28.0 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 17 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: 28.0 inches of depth.
- Days recording measurable snow: about 17 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 20% 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 24
50% probability date
Last Spring Freeze
May 19
50% probability date
Growing Season
128 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,912
Higher = more heating needed
Cooling Degree Days
307
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside MT closest to Holter 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 (47°F here).
- Chamberlain, SD 47°F · 0.0°F off
- Cody, WY 47°F · 0.0°F off
- Dakota City, IA 47°F · 0.0°F off
- Dodge, WI 47°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (13.8" here), excluding temperature-peer places.
- Redondo Beach, CA 13.8" · 0.0" off
- Brigham City, UT 13.8" · 0.0" off
- Buffalo, WY 13.8" · 0.0" off
- Hobbs, NM 13.8" · 0.0" off
Snow and freeze rhythm
When cold and snow define Holter Dam
heating led · dry · mid swing
Holter Dam's energy balance leans toward cold weather: 6,912 annual heating degree days against 307 for cooling. Its 40.0°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 128 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. Holter Dam coldest normal
January
The monthly mean of 28°F (-2°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Holter Dam typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Holter Dam snow peak
January
Holter Dam averages 28.0 inches of snow a year, with January the snowiest month on the normals.
Questions about Holter Dam's climate
How much snow does Holter Dam get? ▼
How cold does Holter Dam get in winter? ▼
How much energy does heating and cooling require in Holter Dam? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Holter Dam's primary station: HOLTER DAM (USC00244241). 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 Holter 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 Holter 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.