Upper Baker Dam, Washington climate: Climate normals at a NOAA weather station
Upper Baker Dam's normal year runs from 29°F January nights to 75°F August afternoons, with 98.2 inches of precipitation and 42 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.6°C, January lows of −2°C, August highs of 24°C, 2,495 mm of precipitation a year.
- NOAA stationUpper Baker Dam
- Station IDUSC00458715
- Location48.65°N 121.69°W
- Elevation690 ft (210 m)
On October 23, the normal high in Upper Baker Dam is 52°F and the normal low 39°F, and the chance of measurable rain or snow is 61%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Upper Baker Dam.
- Jan 38° 29°
- Feb 42° 29°
- Mar 48° 32°
- Apr 56° 36°
- May 64° 42°
- Jun 68° 47°
- Jul 74° 51°
- Aug 75° 51°
- Sep 69° 47°
- Oct 56° 41°
- Nov 44° 34°
- Dec 37° 30°
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 Upper Baker Dam each month?
August is the warmest month, with normal highs of 75°F; January the coldest, with normal lows of 29°F. The most precipitation falls in November (15.97 in), the least in July (1.78 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 38°F | 29°F | 33.4°F | 15.31 | 13.1 | 21 | <1 | 22 | 8 h 40 min |
| February | 42°F | 29°F | 35.8°F | 8.80 | 10.6 | 17 | <1 | 21 | 10 h 10 min |
| March | 48°F | 32°F | 39.9°F | 10.42 | 3.4 | 21 | <1 | 17 | 11 h 50 min |
| April | 56°F | 36°F | 45.8°F | 6.70 | 0.2 | 18 | <1 | 7 | 13 h 40 min |
| May | 64°F | 42°F | 52.8°F | 4.52 | 0.0 | 14 | <1 | 1 | 15 h 10 min |
| June | 68°F | 47°F | 57.2°F | 3.32 | 0.0 | 14 | <1 | <1 | 16 h 10 min |
| July | 74°F | 51°F | 62.6°F | 1.78 | 0.0 | 7 | 2 | <1 | 15 h 50 min |
| August | 75°F | 51°F | 63.3°F | 1.92 | 0.0 | 7 | 1 | <1 | 14 h 30 min |
| September | 69°F | 47°F | 57.9°F | 4.83 | 0.0 | 11 | <1 | <1 | 12 h 40 min |
| October | 56°F | 41°F | 48.2°F | 10.52 | 0.0 | 17 | <1 | 2 | 10 h 50 min |
| November | 44°F | 34°F | 39.0°F | 15.97 | 2.2 | 21 | <1 | 11 | 9 h 10 min |
| December | 37°F | 30°F | 33.6°F | 14.15 | 12.9 | 21 | <1 | 22 | 8 h 20 min |
| Year (annual) | 56°F | 39°F | 47.4°F | 98.24 | 42.4 | 188 | 3 | 102 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 3°C | −2°C | 0.8°C | 389 mm | 33 cm |
| February | 6°C | −2°C | 2.1°C | 224 mm | 27 cm |
| March | 9°C | 0°C | 4.4°C | 265 mm | 9 cm |
| April | 13°C | 2°C | 7.7°C | 170 mm | 1 cm |
| May | 18°C | 5°C | 11.6°C | 115 mm | 0 cm |
| June | 20°C | 8°C | 14.0°C | 84 mm | 0 cm |
| July | 24°C | 11°C | 17.0°C | 45 mm | 0 cm |
| August | 24°C | 11°C | 17.4°C | 49 mm | 0 cm |
| September | 20°C | 8°C | 14.4°C | 123 mm | 0 cm |
| October | 13°C | 5°C | 9.0°C | 267 mm | 0 cm |
| November | 7°C | 1°C | 3.9°C | 406 mm | 6 cm |
| December | 3°C | −1°C | 0.9°C | 359 mm | 33 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00458715; 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 Upper Baker Dam?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, August has the fewest days with rain (7).
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 USC00458715.
When is the last frost at Upper Baker Dam?
In Upper Baker Dam, the last spring frost (32°F) comes after April 24 in half of years and after May 9 in one year in ten; the first autumn frost comes before October 29 in half of years and before October 12 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 241 year in 10 after May 9; 9 in 10 after April 4
- First autumn frost, half of years before
- October 291 year in 10 before October 12; 9 in 10 before November 17
NOAA puts the median frost-free season at 190 days, and the season without a hard freeze (28°F) at 234 days.
A hard freeze (28°F) comes after March 28 in half of springs and before November 17 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Upper Baker Dam in zone 8a in ZIP code 98237, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 8a: the coldest night of a typical year reaches 13°F (29 complete years).
Frost dates for every NOAA station in Washington · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00458715; 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 at Upper Baker Dam?
In a normal year in Upper Baker Dam, 3 days a year reach 90°F, 102 nights fall to 32°F or colder and 188 days bring measurable precipitation.
- Days at 90°F or more
- 3a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 102a normal year
- Days that stay below freezing
- 10high of 32°F or less
- Days with 0.01 inch of precipitation
- 188a normal year
- Days with 1 inch of snow or more
- 13a normal year
The highest temperature in this station's record (since 1965) is 110°F, on June 29, 2021; the lowest is −2°F, on December 30, 1990.
The wettest calendar year on that record is 1990, with 130.44 in; the snowiest season is 1968–69, with 164.7 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00458715; records: ACIS (NOAA Regional Climate Centers), station USC00458715. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Upper Baker Dam?
Over a year 68% of the sunlight that would reach the ground under clear skies gets through the clouds at Upper Baker Dam, 3.5 kWh per square metre a day. August is the sunniest month (81%) and December the cloudiest (53%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 55% | 1.1 |
| February | 62% | 2.0 |
| March | 59% | 2.9 |
| April | 63% | 4.3 |
| May | 66% | 5.3 |
| June | 67% | 5.8 |
| July | 81% | 6.7 |
| August | 81% | 5.7 |
| September | 75% | 4.0 |
| October | 64% | 2.3 |
| November | 55% | 1.2 |
| December | 53% | 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 Upper Baker Dam record?
A normal year at Upper Baker Dam brings 6,468 heating degree days, 20% more than the median U.S. place (5,373), and 87 cooling degree days, 90% 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 1,470 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 980 | 0 |
| February | 819 | 0 |
| March | 780 | 0 |
| April | 576 | 0 |
| May | 380 | 2 |
| June | 242 | 8 |
| July | 108 | 35 |
| August | 89 | 36 |
| September | 219 | 7 |
| October | 522 | 0 |
| November | 780 | 0 |
| December | 975 | 0 |
| Year (annual) | 6,468 | 87 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00458715. 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 Upper Baker Dam been warmer than normal?
2025 averaged 50.0°F, 2.6°F above the 1991-2020 normal of 47.4°F. 4 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 48.2°F | +0.8°F | 106.95 | – |
| 2022 | 47.6°F | +0.2°F | 86.09 | – |
| 2023 | 49.0°F | +1.6°F | 66.66 | – |
| 2025 | 50.0°F | +2.6°F | 94.81 | – |
Over 51 complete years from 1966 to 2025, the station's annual mean temperature rose at a fitted 3.9°F per century (+0.22°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00458715; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Upper Baker Dam's climate compare?
Upper Baker Dam is warmer than 15 of the 96 places with their own NOAA record in Washington, and wetter than 86. Across the 7,247 U.S. stations with normals, its annual mean of 47.4°F is warmer than 29%.
In the Köppen classification computed from these normals, Upper Baker Dam is Cfb: temperate, no dry season, 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.
Questions about Upper Baker Dam's climate
What is the coldest month at Upper Baker Dam?
January, with a normal high of 38°F and a normal low of 29°F. The warmest is August (75°F by day, 51°F at night).
Does it snow at Upper Baker Dam?
Yes: 42 inches in a normal year, falling on 17 days with 0.1 inch or more, the most in January (13.1 inches).
What is the rainiest month at Upper Baker Dam?
November, with 15.97 in of precipitation in a normal year; the driest is July with 1.78 in.
What plant hardiness zone is Upper Baker Dam in?
The USDA's 2023 map puts Upper Baker Dam in zone 8a in ZIP code 98237, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches 13°F (29 years, 1991-2020): zone 8a.
How late can frost come at Upper Baker Dam?
In half of years the last 32°F night comes after April 24; in one year in ten it comes after May 9. Waiting until May 9 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Washington climateThe statewide normals and every place in the state
- Concrete, WA8 miles from this station, 50.7°F a year
- Newhalem, WA21 miles from this station, 50.2°F a year
- Diablo Dam, WA25 miles from this station, 49.2°F a year
- Sedro-Woolley, WA27 miles from this station, 51.3°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made