Shell, Wyoming climate: Normal weather by month, frost dates and records
Shell's normal year runs from 6°F January nights to 89°F July afternoons, with 10.1 inches of precipitation and 28 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.1°C, January lows of −14°C, July highs of 32°C, 257 mm of precipitation a year.
- NOAA stationShell
- Station IDUSC00488124
- Location44.54°N 107.78°W
- Elevation4,242 ft (1,293 m)
- Population (census place)34
On October 23, the normal high in Shell is 57°F and the normal low 27°F, and the chance of measurable rain or snow is 16%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Shell.
- Jan 33° 6°
- Feb 37° 11°
- Mar 50° 22°
- Apr 59° 29°
- May 69° 39°
- Jun 79° 47°
- Jul 89° 54°
- Aug 87° 51°
- Sep 76° 42°
- Oct 60° 30°
- Nov 45° 18°
- Dec 34° 8°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Shell each month?
July is the warmest month, with normal highs of 89°F; January the coldest, with normal lows of 6°F. The most precipitation falls in May (1.88 in), the least in December (0.44 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 33°F | 6°F | 19.5°F | 0.47 | 7.3 | 5 | <1 | 31 | 9 h 10 min |
| February | 37°F | 11°F | 24.1°F | 0.50 | 6.4 | 4 | <1 | 28 | 10 h 30 min |
| March | 50°F | 22°F | 36.0°F | 0.49 | 2.7 | 4 | <1 | 29 | 11 h 50 min |
| April | 59°F | 29°F | 44.0°F | 1.05 | 1.4 | 6 | <1 | 20 | 13 h 30 min |
| May | 69°F | 39°F | 53.9°F | 1.88 | 0.0 | 10 | <1 | 6 | 14 h 50 min |
| June | 79°F | 47°F | 63.2°F | 1.35 | 0.0 | 7 | 5 | <1 | 15 h 30 min |
| July | 89°F | 54°F | 71.3°F | 0.72 | 0.0 | 4 | 17 | <1 | 15 h 20 min |
| August | 87°F | 51°F | 68.9°F | 0.46 | 0.0 | 4 | 15 | <1 | 14 h 10 min |
| September | 76°F | 42°F | 58.7°F | 1.07 | 0.0 | 5 | 3 | 4 | 12 h 40 min |
| October | 60°F | 30°F | 44.9°F | 0.99 | 0.9 | 6 | <1 | 21 | 11 h |
| November | 45°F | 18°F | 31.7°F | 0.68 | 3.9 | 5 | <1 | 29 | 9 h 40 min |
| December | 34°F | 8°F | 20.8°F | 0.44 | 5.6 | 4 | <1 | 31 | 8 h 50 min |
| Year (annual) | 60°F | 30°F | 44.8°F | 10.10 | 28.2 | 63 | 41 | 198 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −14°C | −6.9°C | 12 mm | 19 cm |
| February | 3°C | −12°C | −4.4°C | 13 mm | 16 cm |
| March | 10°C | −5°C | 2.2°C | 12 mm | 7 cm |
| April | 15°C | −1°C | 6.7°C | 27 mm | 4 cm |
| May | 20°C | 4°C | 12.2°C | 48 mm | 0 cm |
| June | 26°C | 8°C | 17.3°C | 34 mm | 0 cm |
| July | 32°C | 12°C | 21.8°C | 18 mm | 0 cm |
| August | 31°C | 11°C | 20.5°C | 12 mm | 0 cm |
| September | 24°C | 5°C | 14.8°C | 27 mm | 0 cm |
| October | 16°C | −1°C | 7.2°C | 25 mm | 2 cm |
| November | 7°C | −8°C | −0.2°C | 17 mm | 10 cm |
| December | 1°C | −13°C | −6.2°C | 11 mm | 14 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00488124; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Shell?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (5).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00488124.
When is the last frost in Shell?
In Shell, the last spring frost (32°F) comes after May 16 in half of years and after June 3 in one year in ten; the first autumn frost comes before September 24 in half of years and before September 10 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- May 161 year in 10 after June 3; 9 in 10 after May 4
- First autumn frost, half of years before
- September 241 year in 10 before September 10; 9 in 10 before October 7
NOAA puts the median frost-free season at 130 days, and the season without a hard freeze (28°F) at 152 days.
A hard freeze (28°F) comes after May 4 in half of springs and before October 4 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Shell in zone 5a in ZIP code 82441, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Shell's NOAA station is in zone 4b: the coldest night of a typical year reaches −22°F (15 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Wyoming · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00488124; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
How hot and how cold does it get in Shell?
In a normal year in Shell, 41 days a year reach 90°F (2 of them 100°F or more), 198 nights fall to 32°F or colder and 63 days bring measurable precipitation.
- Days at 90°F or more
- 41a normal year
- Days at 100°F or more
- 2a normal year
- Nights at 32°F or colder
- 198a normal year
- Days that stay below freezing
- 42high of 32°F or less
- Days with 0.01 inch of precipitation
- 63a normal year
- Days with 1 inch of snow or more
- 12a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00488124.
How sunny is Shell?
Over a year 77% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Shell, 4.4 kWh per square metre a day. July is the sunniest month (87%) and April the cloudiest (69%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 2.0 |
| February | 76% | 3.0 |
| March | 73% | 4.0 |
| April | 69% | 5.0 |
| May | 70% | 5.9 |
| June | 81% | 7.2 |
| July | 87% | 7.3 |
| August | 86% | 6.2 |
| September | 83% | 4.9 |
| October | 74% | 3.1 |
| November | 72% | 2.0 |
| December | 70% | 1.6 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Shell need?
A normal year in Shell brings 7,809 heating degree days, 45% more than the median U.S. place (5,373), and 466 cooling degree days, 49% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,196 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,409 | 0 |
| February | 1,145 | 0 |
| March | 898 | 0 |
| April | 630 | 0 |
| May | 351 | 6 |
| June | 117 | 61 |
| July | 17 | 212 |
| August | 35 | 157 |
| September | 216 | 28 |
| October | 622 | 1 |
| November | 999 | 0 |
| December | 1,372 | 0 |
| Year (annual) | 7,809 | 466 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00488124. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Shell been warmer than normal lately?
2025 averaged 46.7°F, 1.9°F above the 1991-2020 normal of 44.8°F. 3 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 46.0°F | +1.2°F | 10.21 | 39.8 |
| 2022 | 43.6°F | −1.2°F | 10.42 | 46.7 |
| 2024 | 47.3°F | +2.5°F | 9.68 | 18.3 |
| 2025 | 46.7°F | +1.9°F | 10.52 | 30.8 |
Source: observed years: ACIS, station USC00488124. A year counts only with all twelve months complete.
How does Shell's climate compare?
Shell is warmer than 39 of the other 70 places with their own NOAA record in Wyoming, and wetter than 20. Across the 7,247 U.S. stations with normals, its annual mean of 44.8°F is warmer than 18%.
In the Köppen classification computed from these normals, Shell is BSk: cold semi-arid steppe. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Questions about Shell's climate
What is the coldest month in Shell?
January, with a normal high of 33°F and a normal low of 6°F. The warmest is July (89°F by day, 54°F at night).
Does it snow in Shell?
Yes: 28 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in January (7.3 inches).
What is the rainiest month in Shell?
May, with 1.88 in of precipitation in a normal year; the driest is December with 0.44 in.
What plant hardiness zone is Shell in?
The USDA's 2023 map puts Shell in zone 5a in ZIP code 82441, the nearest ZIP area. By the same method at Shell's NOAA station, the coldest night of a typical year reaches −22°F (15 years, 1991-2020): zone 4b.
How late can frost come in Shell?
In half of years the last 32°F night comes after May 16; in one year in ten it comes after June 3. Waiting until June 3 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Wyoming climateThe statewide normals and every place in the state
- Greybull, WY15 miles from this station, 46.2°F a year
- Basin, WY17 miles from this station, 48.9°F a year
- Burgess Junction, WY21 miles from this station, 34.5°F a year
- Emblem, WY30 miles from this station, 44.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made