Mayfield Power Plant, Washington climate: Climate normals at a NOAA weather station
Mayfield Power Plant's normal year runs from 34°F December nights to 81°F August afternoons, with 58.7 inches of precipitation and 3 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.9°C, December lows of 1°C, August highs of 27°C, 1,492 mm of precipitation a year.
- NOAA stationMayfield Power Plant
- Station IDUSC00455110
- Location46.50°N 122.59°W
- Elevation280 ft (85 m)
On October 23, the normal high in Mayfield Power Plant is 59°F and the normal low 41°F, and the chance of measurable rain or snow is 56%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Mayfield Power Plant.
- Jan 45° 33°
- Feb 49° 34°
- Mar 54° 35°
- Apr 60° 39°
- May 69° 43°
- Jun 72° 48°
- Jul 81° 51°
- Aug 81° 52°
- Sep 74° 48°
- Oct 62° 43°
- Nov 51° 38°
- Dec 44° 34°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like at Mayfield Power Plant each month?
August is the warmest month, with normal highs of 81°F; December the coldest, with normal lows of 34°F. The most precipitation falls in November (8.44 in), the least in July (0.91 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 45°F | 33°F | 39.1°F | 8.06 | 1.1 | 20 | <1 | 14 | 9 h |
| February | 49°F | 34°F | 41.3°F | 5.78 | 1.3 | 16 | <1 | 13 | 10 h 20 min |
| March | 54°F | 35°F | 44.6°F | 6.31 | 0.0 | 20 | <1 | 11 | 11 h 50 min |
| April | 60°F | 39°F | 49.3°F | 5.45 | 0.0 | 18 | <1 | 3 | 13 h 30 min |
| May | 69°F | 43°F | 56.1°F | 3.81 | 0.0 | 14 | 2 | 1 | 15 h |
| June | 72°F | 48°F | 60.0°F | 2.69 | 0.0 | 12 | 3 | <1 | 15 h 50 min |
| July | 81°F | 51°F | 66.3°F | 0.91 | 0.0 | 6 | 7 | <1 | 15 h 30 min |
| August | 81°F | 52°F | 66.4°F | 1.30 | 0.0 | 6 | 10 | <1 | 14 h 20 min |
| September | 74°F | 48°F | 61.2°F | 2.46 | 0.0 | 10 | 3 | <1 | 12 h 40 min |
| October | 62°F | 43°F | 52.2°F | 5.39 | 0.0 | 16 | <1 | 1 | 11 h |
| November | 51°F | 38°F | 44.3°F | 8.44 | 0.0 | 19 | <1 | 8 | 9 h 30 min |
| December | 44°F | 34°F | 38.9°F | 8.13 | 1.0 | 20 | <1 | 15 | 8 h 40 min |
| Year (annual) | 62°F | 41°F | 51.7°F | 58.73 | 3.4 | 177 | 24 | 66 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 7°C | 1°C | 3.9°C | 205 mm | 3 cm |
| February | 10°C | 1°C | 5.2°C | 147 mm | 3 cm |
| March | 12°C | 2°C | 7.0°C | 160 mm | 0 cm |
| April | 16°C | 4°C | 9.6°C | 138 mm | 0 cm |
| May | 21°C | 6°C | 13.4°C | 97 mm | 0 cm |
| June | 22°C | 9°C | 15.6°C | 68 mm | 0 cm |
| July | 27°C | 11°C | 19.1°C | 23 mm | 0 cm |
| August | 27°C | 11°C | 19.1°C | 33 mm | 0 cm |
| September | 24°C | 9°C | 16.2°C | 62 mm | 0 cm |
| October | 17°C | 6°C | 11.2°C | 137 mm | 0 cm |
| November | 11°C | 3°C | 6.8°C | 214 mm | 0 cm |
| December | 7°C | 1°C | 3.8°C | 207 mm | 3 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00455110; 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.
Which months are mildest at Mayfield Power Plant?
Normal highs sit between 65°F and 85°F in May, June, July, August and September. Of those, July has the fewest days with rain (6).
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 USC00455110.
When is the last frost at Mayfield Power Plant?
In Mayfield Power Plant, the last spring frost (32°F) comes after April 7 in half of years and after May 8 in one year in ten; the first autumn frost comes before November 13 in half of years and before October 24 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
- April 71 year in 10 after May 8; 9 in 10 after March 16
- First autumn frost, half of years before
- November 131 year in 10 before October 24; 9 in 10 before December 4
NOAA puts the median frost-free season at 215 days, and the season without a hard freeze (28°F) at 269 days.
A hard freeze (28°F) comes after March 6 in half of springs and before December 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Mayfield Power Plant in zone 8b in ZIP code 98582, the nearest ZIP area.
Frost dates for every NOAA station in Washington · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00455110; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. 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 at Mayfield Power Plant?
In a normal year in Mayfield Power Plant, 24 days a year reach 90°F (3 of them 100°F or more), 66 nights fall to 32°F or colder and 177 days bring measurable precipitation.
- Days at 90°F or more
- 24a normal year
- Days at 100°F or more
- 3a normal year
- Nights at 32°F or colder
- 66a normal year
- Days that stay below freezing
- 3high of 32°F or less
- Days with 0.01 inch of precipitation
- 177a normal year
- Days with 1 inch of snow or more
- 1a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00455110.
How sunny is it at Mayfield Power Plant?
Over a year 67% of the sunlight that would reach the ground under clear skies gets through the clouds at Mayfield Power Plant, 3.5 kWh per square metre a day. July is the sunniest month (78%) and December the cloudiest (52%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 52% | 1.1 |
| February | 59% | 2.0 |
| March | 57% | 2.9 |
| April | 62% | 4.2 |
| May | 66% | 5.2 |
| June | 67% | 5.7 |
| July | 78% | 6.4 |
| August | 78% | 5.4 |
| September | 75% | 4.0 |
| October | 65% | 2.4 |
| November | 55% | 1.3 |
| December | 52% | 0.9 |
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 many heating and cooling degree days does Mayfield Power Plant record?
A normal year at Mayfield Power Plant brings 5,086 heating degree days, 5% fewer than the median U.S. place (5,373), and 237 cooling degree days, 74% fewer than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,054 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 805 | 0 |
| February | 662 | 0 |
| March | 631 | 0 |
| April | 471 | 2 |
| May | 284 | 10 |
| June | 175 | 26 |
| July | 49 | 88 |
| August | 43 | 86 |
| September | 139 | 25 |
| October | 398 | 1 |
| November | 623 | 0 |
| December | 807 | 0 |
| Year (annual) | 5,086 | 237 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00455110. 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.
Have recent years at Mayfield Power Plant been warmer than normal?
2025 averaged 53.9°F, 2.2°F above the 1991-2020 normal of 51.7°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 52.7°F | +1.0°F | 67.66 | 19.3 |
| 2022 | 52.4°F | +0.7°F | 69.24 | – |
| 2023 | 52.9°F | +1.1°F | 58.47 | – |
| 2024 | 52.5°F | +0.8°F | – | – |
| 2025 | 53.9°F | +2.2°F | 51.74 | – |
Source: observed years: ACIS, station USC00455110. A year counts only with all twelve months complete.
How does Mayfield Power Plant's climate compare?
Mayfield Power Plant is warmer than 75 of the 96 places with their own NOAA record in Washington, and wetter than 74. Across the 7,247 U.S. stations with normals, its annual mean of 51.7°F is warmer than 48%.
In the Köppen classification computed from these normals, Mayfield Power Plant is Csb: temperate, dry-summer, warm summer. 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.
Which places near Mayfield Power Plant share this climate record?
2 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- Mossyrock, WA803 people · 5 mi E
- Onalaska, WA657 people · 8 mi NW
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Mayfield Power Plant's climate
What is the coldest month at Mayfield Power Plant?
December, with a normal high of 44°F and a normal low of 34°F. The warmest is August (81°F by day, 52°F at night).
Does it snow at Mayfield Power Plant?
Yes: 3 inches in a normal year, falling on 2 days with 0.1 inch or more, the most in February (1.3 inches).
What is the rainiest month at Mayfield Power Plant?
November, with 8.44 in of precipitation in a normal year; the driest is July with 0.91 in.
What plant hardiness zone is Mayfield Power Plant in?
The USDA's 2023 map puts Mayfield Power Plant in zone 8b in ZIP code 98582, the nearest ZIP area.
How late can frost come at Mayfield Power Plant?
In half of years the last 32°F night comes after April 7; in one year in ten it comes after May 8. Waiting until May 8 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Washington climateThe statewide normals and every place in the state
- Toledo, WA11 miles from this station, 52.3°F a year
- Glenoma, WA22 miles from this station, 50.0°F a year
- Centralia, WA22 miles from this station, 51.5°F a year
- Longview, WA29 miles from this station, 53.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made