Diversion Dam, WY Climate: Temperature & Rain by Month
Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score
30-year climate normals (1991-2020) from Diversion Dam's primary NOAA station, DIVERSION DAM.
The climate verdict for Diversion Dam
Dryness leads the climate profile for Diversion Dam, Wyoming, with 9.8 inches of precipitation a year. NOAA records an annual average of 44°F. At 29/100 (below average) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 1% of scores.
- 44°F
- yearly average temperature, NOAA normal
- 29/100
- comfort score, above 1% of station-mapped location scores
- 9.8"
- annual precipitation · 29" snow
- 122 days
- growing season, frost-free days
Diversion Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00482595 · Diversion Dam, WY 44°F mean · 9.8" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-ARID · SWING-WIDE · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 44°F
- RANK-COOL #892
- PHOTO-FINISH ≈ Moccasin
- PRCP-ARID 9.8"
- SWING-WIDE 47°F
- COMF-LOW 29/100
- LOAD-HEAT 8,058 HDD
- STN-1 USC00482595
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Moccasin Exp Stn, MT (+ 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 WY station list.
- Diversion Dam (this station) 44°F
- Hot Ryegate, MT 44°F
- Near Moccasin, MT 44°F
- Near Bynum, MT 44°F
- Cold Plymouth, NH 43°F
Diversion Dam sits in Wyoming, the #5 coldest U.S. state at 43.3°F statewide annual average - see all 50 coldest states ranked by NOAA normals
Climate Living Index · Diversion Dam
Diversion Dam: 15/100 · grade F
Diversion 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 Diversion Dam, not an official NOAA rating. Rankings still use Comfort Score 29/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 28.8 inches/year | 40/100 · D |
| Annual temperature balance | 43.5°F · 24.0° from 67.5°F | 14/100 · F |
| Normal heat + freeze calendar | 205 calendar days | 11/100 · F |
| Precipitation balance | 9.8 in · 25.3 from 35 in | 11/100 · F |
| Frost-free season | 122 days/year | 8/100 · F |
Diversion Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Diversion 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
- 67.8°F
- Coldest month
- 21.1°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 Diversion Dam sits across the climate record
Three NOAA fields for Diversion 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 87%
- Among 6,861 stations, Diversion Dam sits in the cooler third of annual means.
- Annual precipitation
- Drier than 94%
- Diversion Dam's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- 67th percentile swing
- Typical seasonal amplitude versus 6,861 complete station-years.
How Diversion Dam compares across U.S. station-mapped locations
Diversion Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
29 1st percentile score exceeds 1% 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%). This entry sits in this band.
- 30–40: 280 station-mapped locations (5%). Above this entry.
- 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
Diversion Dam's measured station temperature trend
MethodologyAcross 32 complete annual observations from 1950 to 2023, DIVERSION DAM warmed at a fitted rate of 0.05°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Diversion Dam primary station fitted change +0.05 °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 | 36°F (2°C) | 8°F (-13°C) | 22°F (-5°C) | 0.2" | 3.3" | 30.5 | 0.0 |
| February | 38°F (3°C) | 11°F (-12°C) | 25°F (-4°C) | 0.3" | 4.9" | 27.7 | 0.0 |
| March | 49°F (9°C) | 21°F (-6°C) | 35°F (2°C) | 0.7" | 4.9" | 28.9 | 0.0 |
| April | 56°F (13°C) | 28°F (-2°C) | 42°F (6°C) | 1.2" | 5.1" | 22.1 | 0.0 |
| May | 65°F (18°C) | 37°F (3°C) | 51°F (11°C) | 2.3" | 1.0" | 7.7 | 0.0 |
| June | 76°F (24°C) | 44°F (7°C) | 60°F (16°C) | 1.3" | 0.1" | 0.5 | 1.4 |
| July | 85°F (30°C) | 51°F (10°C) | 68°F (20°C) | 0.7" | 0.0" | 0.0 | 8.0 |
| August | 83°F (28°C) | 49°F (9°C) | 66°F (19°C) | 0.7" | 0.0" | 0.1 | 4.3 |
| September | 73°F (23°C) | 41°F (5°C) | 57°F (14°C) | 1.0" | 0.5" | 4.1 | 0.3 |
| October | 59°F (15°C) | 30°F (-1°C) | 44°F (7°C) | 0.9" | 2.2" | 19.9 | 0.0 |
| November | 45°F (7°C) | 17°F (-8°C) | 31°F (-1°C) | 0.4" | 3.8" | 28.0 | 0.0 |
| December | 34°F (1°C) | 8°F (-13°C) | 21°F (-6°C) | 0.2" | 3.0" | 30.9 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 87°F around July 26, short of 90°F on every date, while 205 dates carry a normal low at or below freezing, the coldest 7°F near December 21.
The freezing stretch
The normal low stays at or below 32°F into May 1, then returns to freezing around October 10, covering 205 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 11, when 25% of years recorded at least a hundredth of an inch. The driest is January 16 at 6%. Summed across the calendar, that is about 48 wet dates a year.
The widest day
July 12 carries the biggest normal gap between afternoon and dawn, 35°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Diversion Dam.
Where Diversion Dam Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 205 nights a year, placing this among the most frost-prone tenth of ranked stations.
Aridity defines the water calendar: about 10 inches in a normal year lands this among the driest tenth of ranked stations.
Diversion 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: 3.3"
1.7 days with precipitation
Snow: 4.9"
2.3 days with precipitation
Snow: 4.9"
3.4 days with precipitation
Snow: 5.1"
5.8 days with precipitation
Snow: 1.0"
7.6 days with precipitation
Snow: 0.1"
5.7 days with precipitation
4.3 days with precipitation
4.6 days with precipitation
Snow: 0.5"
4.5 days with precipitation
Snow: 2.2"
3.5 days with precipitation
Snow: 3.8"
2.3 days with precipitation
Snow: 3.0"
1.8 days with precipitation
Diversion Dam spreads its precipitation across the year
Neither half of the year dominates here: June through August take 27% of the annual total and December through February 7%, with neither reaching the 35% that would mark a distinct wet season. Diversion Dam has no dry season to plan around, though it does carry a wide 46.7°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: May averages 2.3" and January 0.2". The three wettest months together take 49% 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.
How Diversion Dam's precipitation splits across the calendar
About 47 days a year record measurable precipitation here, carrying 9.8" between them, or roughly 0.21 inches on a typical wet day. That sits in the middle band: neither the many-light-days pattern of the Pacific Northwest and the Great Lakes, nor the few-heavy-events pattern of the Gulf and the desert Southwest.
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.
Winter brings real snow to Diversion Dam
Diversion Dam averages 28.8 inches of snowfall a year, with April the snowiest month on the normals, spread across roughly 15 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: 28.8 inches of depth.
- Days recording measurable snow: about 15 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 30% 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 20
50% probability date
Last Spring Freeze
May 21
50% probability date
Growing Season
122 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
8,058
Higher = more heating needed
Cooling Degree Days
238
Higher = more cooling needed
Warmest Month
July
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside WY closest to Diversion 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 (44°F here).
- Alpena, MI 44°F · 0.0°F off
- Amery, WI 44°F · 0.0°F off
- Blanca, CO 44°F · 0.0°F off
- Bynum, MT 44°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (9.8" here), excluding temperature-peer places.
- John Day, OR 9.8" · 0.0" off
- San Diego, CA 9.8" · 0.0" off
- Hagerman, ID 9.8" · 0.1" off
- Kivalina, AK 9.7" · 0.1" off
Snow and freeze rhythm
When cold and snow define Diversion Dam
heating led · dry · mid swing
Diversion Dam's energy balance leans toward cold weather: 8,058 annual heating degree days against 238 for cooling. Its 46.7°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 122 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. Diversion Dam coldest normal
December
Averaging 21°F (-6°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Diversion Dam typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Diversion Dam snow peak
April
Diversion Dam averages 28.8 inches of snow a year, with April the snowiest month on the normals.
Questions about Diversion Dam's climate
How much snow does Diversion Dam get? ▼
How cold does Diversion 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 Diversion Dam's primary station: DIVERSION DAM (USC00482595). 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 Diversion 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 Diversion 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.