Green Rvr, WY 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 Green Rvr's primary NOAA station, GREEN RVR.
The climate verdict for Green Rvr
Dryness leads the climate profile for Green Rvr, Wyoming, with 10.3 inches of precipitation a year. NOAA records an annual average of 44°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.
- 44°F
- average temperature, NOAA 1991-2020 normal
- 39/100
- comfort score, above 4% of station-mapped location scores
- 10.3"
- annual precipitation · 39" snow
- 121 days
- growing season, frost-free days
Green Rvr: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00484065 · Green Rvr, WY 44°F mean · 10.3" 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 #1,029
- PHOTO-FINISH ≈ Rumford
- PRCP-ARID 10.3"
- SWING-WIDE 50°F
- COMF-LOW 39/100
- LOAD-HEAT 7,939 HDD
- STN-1 USC00484065
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Rumford, ME ( -0.1 °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.
- Green Rvr (this station) 44°F
- Cold Rumford, ME 44°F
- Near Howe, ID 44°F
- Near Sturgeon Bay, WI 44°F
- Near Hollis, ME 44°F
Green Rvr 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 · Green Rvr
Green Rvr: 15/100 · grade F
Green Rvr publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Green Rvr, not an official NOAA rating. Rankings still use Comfort Score 39/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 38.5 inches/year | 29/100 · F |
| Annual temperature balance | 44.1°F · 23.4° from 67.5°F | 16/100 · F |
| Normal heat + freeze calendar | 200 calendar days | 14/100 · F |
| Precipitation balance | 10.3 in · 24.7 from 35 in | 13/100 · F |
| Frost-free season | 121 days/year | 7/100 · F |
Green Rvr · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Green Rvr'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
- 69.7°F
- Coldest month
- 19.6°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 Green Rvr sits across the climate record
Three NOAA fields for Green Rvr's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 85%
- Among 6,861 stations, Green Rvr sits in the cooler third of annual means.
- Annual precipitation
- Drier than 93%
- Green Rvr's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Wider than 81%
- Warmest-to-coldest month gap for Green Rvr is large versus 6,861 complete station-years.
How Green Rvr compares across U.S. station-mapped locations
Green Rvr'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
Green Rvr's measured station temperature trend
MethodologyAcross 65 complete annual observations from 1905 to 2025, GREEN RVR warmed at a fitted rate of 0.19°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Green Rvr primary station fitted change +0.19 °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 | 31°F (-1°C) | 8°F (-13°C) | 20°F (-7°C) | 0.7" | 6.3" | 30.6 | 0.0 |
| February | 36°F (2°C) | 13°F (-11°C) | 25°F (-4°C) | 0.5" | 7.6" | 27.7 | 0.0 |
| March | 47°F (8°C) | 23°F (-5°C) | 35°F (2°C) | 0.8" | 5.4" | 29.3 | 0.0 |
| April | 56°F (14°C) | 29°F (-1°C) | 43°F (6°C) | 1.3" | 3.9" | 21.6 | 0.0 |
| May | 66°F (19°C) | 38°F (3°C) | 52°F (11°C) | 1.7" | 0.9" | 7.5 | 0.2 |
| June | 78°F (26°C) | 46°F (8°C) | 62°F (17°C) | 0.9" | 0.0" | 0.8 | 4.1 |
| July | 87°F (30°C) | 53°F (12°C) | 70°F (21°C) | 0.5" | 0.0" | 0.0 | 14.1 |
| August | 85°F (29°C) | 51°F (10°C) | 68°F (20°C) | 0.6" | 0.0" | 0.2 | 10.4 |
| September | 76°F (24°C) | 41°F (5°C) | 58°F (15°C) | 0.9" | 0.3" | 4.1 | 1.4 |
| October | 61°F (16°C) | 30°F (-1°C) | 46°F (8°C) | 1.0" | 2.4" | 19.6 | 0.0 |
| November | 44°F (7°C) | 19°F (-7°C) | 31°F (0°C) | 0.7" | 5.0" | 28.2 | 0.0 |
| December | 32°F (0°C) | 10°F (-12°C) | 21°F (-6°C) | 0.6" | 6.7" | 30.9 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 88°F around July 26, short of 90°F on every date, while 200 dates carry a normal low at or below freezing, the coldest 7°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into April 28, then returns to freezing around October 12, covering 200 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 7, when 27% of years recorded at least a hundredth of an inch. The driest is July 14 at 15%. Summed across the calendar, that is about 71 wet dates a year.
The widest day
September 6 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 Green Rvr.
Where Green Rvr Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 200 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.
Green Rvr 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: 6.3"
5.2 days with precipitation
Snow: 7.6"
4.8 days with precipitation
Snow: 5.4"
6.2 days with precipitation
Snow: 3.9"
7.4 days with precipitation
Snow: 0.9"
9.1 days with precipitation
4.9 days with precipitation
4.6 days with precipitation
5.4 days with precipitation
Snow: 0.3"
6.1 days with precipitation
Snow: 2.4"
6.0 days with precipitation
Snow: 5.0"
5.1 days with precipitation
Snow: 6.7"
5.8 days with precipitation
Green Rvr spreads its precipitation across the year
Neither half of the year dominates here: June through August take 20% of the annual total and December through February 18%, with neither reaching the 35% that would mark a distinct wet season. Green Rvr has no dry season to plan around, though it does carry a wide 50.1°F gap between its warmest and coldest month.
The gap between the wettest and driest month still matters: May averages 1.7" and July 0.5". The three wettest months together take 39% 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.
Green Rvr is dry, and what does fall arrives gently
Only about 71 days a year record measurable precipitation here, 19% of the calendar, and they carry 10.3" 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 9 wet days; the driest is July 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 Green Rvr
Green Rvr averages 38.5 inches of snowfall a year, with February the snowiest month on the normals, spread across roughly 26 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: 38.5 inches of depth.
- Days recording measurable snow: about 26 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 37% 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 22
50% probability date
Last Spring Freeze
May 24
50% probability date
Growing Season
121 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,939
Higher = more heating needed
Cooling Degree Days
350
Higher = more cooling needed
Warmest Month
July
Coldest Month
January
Nationwide similar cities
Other rankable U.S. places outside WY closest to Green Rvr 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).
- Aberdeen, SD 44°F · 0.0°F off
- Belfast, ME 44°F · 0.0°F off
- Bushnell, NE 44°F · 0.0°F off
- Cambridge, MN 44°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (10.3" here), excluding temperature-peer places.
- San Simon, AZ 10.3" · 0.0" off
- Van Horn, TX 10.3" · 0.0" off
- Visalia, CA 10.3" · 0.0" off
- Prineville, OR 10.3" · 0.0" off
Snow and freeze rhythm
When cold and snow define Green Rvr
heating led · dry · mid swing
Green Rvr's energy balance leans toward cold weather: 7,939 annual heating degree days against 350 for cooling. Its 50.1°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.
-
1. Green Rvr coldest normal
January
Averaging 20°F (-7°C), this month sits below freezing for the month as a whole, not merely overnight.
-
2. Green Rvr typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Green Rvr snow peak
February
Green Rvr averages 38.5 inches of snow a year, with February the snowiest month on the normals.
Questions about Green Rvr's climate
How much snow does Green Rvr get? ▼
How many days above 90°F does Green Rvr get? ▼
How much energy does heating and cooling require in Green Rvr? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Green Rvr's primary station: GREEN RVR (USC00484065). 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 Green Rvr; 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 Green Rvr 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.