Foster Dam, OR Climate: Temperature & Rain by Month
Annual temperature and rainfall from NOAA NCEI's 1991–2020 normals →; comfort score computed by PlainClimate
30-year climate normals (1991-2020) from Foster Dam's primary NOAA station, FOSTER DAM.
The climate verdict for Foster Dam
Water is the standout signal in Foster Dam, Oregon: 54.5 inches of precipitation in a normal year. Against that wet profile, NOAA records an annual average of 52°F. Its climate comfort score of 63/100 (good) lands mid-pack nationally, exceeding 46% of station-mapped location scores.
- 52°F
- yearly average temperature, NOAA normal
- 63/100
- comfort score, above 46% of station-mapped location scores
- 54.5"
- annual precipitation
- 199 days
- frost-free days per growing season
Foster Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00353047 · Foster Dam, OR 52°F mean · 54.5" precip
TEMP-COOL · RANK-MID · PHOTO-FINISH · PRCP-WET · SWING-NARROW · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 52°F
- RANK-MID #3,499
- PHOTO-FINISH ≈ Toledo Faa
- PRCP-WET 54.5"
- SWING-NARROW 26°F
- COMF-MID 63/100
- LOAD-HEAT 4,811 HDD
- STN-1 USC00353047
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Toledo Faa, WA ( -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 OR station list.
- Foster Dam (this station) 52°F
- Cold Corvallis, OR 52°F
- Near Toledo Faa, WA 52°F
- Near Cottage Grove, OR 52°F
- Near Bremerton, WA 52°F
Climate Living Index · Foster Dam
Foster Dam: 68/100 · grade C
Foster 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 Foster Dam, not an official NOAA rating. Rankings still use Comfort Score 63/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 0 calendar days | 100/100 · A |
| Snowfall burden | 0.1 inches/year | 89/100 · A |
| Frost-free season | 199 days/year | 64/100 · C |
| Annual temperature balance | 52.4°F · 15.1° from 67.5°F | 51/100 · D |
| Precipitation balance | 54.5 in · 19.5 from 35 in | 30/100 · F |
Foster Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Foster Dam is a temperate Köppen climate: Csb
Coldest-month mean 40.4°F and warmest-month mean 66.4°F place this station in temperate, dry-summer, warm summer climates (Csb). Class Csb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, dry-summer, warm summer.
- Köppen code
- Csb
- Group
- Temperate
- Warmest month
- 66.4°F
- Coldest month
- 40.4°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 Foster Dam sits across the climate record
Three NOAA fields for Foster Dam's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 51st percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- Top 12% wettest
- Foster Dam's annual total ranks in the wetter third of 6,352 measured normals.
- Seasonal temperature swing
- Narrower than 94%
- Warmest-to-coldest month gap for Foster Dam is compact versus 6,861 complete station-years.
How Foster Dam compares across U.S. station-mapped locations
Foster Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
63 46th percentile score exceeds 46% 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%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). Below this entry.
- 50–60: 1,329 station-mapped locations (21%). Below this entry.
- 60–70: 1,236 station-mapped locations (20%). This entry sits in this band.
- 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
Foster Dam's measured station temperature trend
MethodologyAcross 48 complete annual observations from 1970 to 2024, FOSTER DAM warmed at a fitted rate of 0.14°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Foster Dam primary station fitted change +0.14 °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 | 48°F (9°C) | 34°F (1°C) | 41°F (5°C) | 7.2" | 0.1" | 12.6 | 0.0 |
| February | 51°F (11°C) | 35°F (1°C) | 43°F (6°C) | 5.6" | 0.0" | 11.4 | 0.0 |
| March | 56°F (13°C) | 37°F (3°C) | 46°F (8°C) | 6.3" | 0.0" | 6.5 | 0.0 |
| April | 60°F (16°C) | 40°F (4°C) | 50°F (10°C) | 5.4" | 0.0" | 2.3 | 0.0 |
| May | 67°F (19°C) | 44°F (7°C) | 56°F (13°C) | 3.8" | 0.0" | 0.5 | 0.3 |
| June | 73°F (23°C) | 48°F (9°C) | 60°F (16°C) | 2.5" | 0.0" | 0.0 | 1.4 |
| July | 82°F (28°C) | 51°F (11°C) | 66°F (19°C) | 0.5" | 0.0" | 0.0 | 5.9 |
| August | 83°F (28°C) | 50°F (10°C) | 66°F (19°C) | 0.6" | 0.0" | 0.0 | 6.6 |
| September | 76°F (25°C) | 47°F (8°C) | 62°F (16°C) | 2.0" | 0.0" | 0.1 | 2.3 |
| October | 64°F (18°C) | 42°F (5°C) | 53°F (12°C) | 4.6" | 0.0" | 2.1 | 0.0 |
| November | 53°F (12°C) | 38°F (3°C) | 45°F (7°C) | 7.6" | 0.0" | 7.7 | 0.0 |
| December | 47°F (8°C) | 34°F (1°C) | 40°F (5°C) | 8.4" | 0.0" | 12.1 | 0.0 |
The year, day by day
The calendar barely moves in Foster Dam: no date carries a normal high of 90°F or a normal low at freezing. The year runs between 34°F near December 22 and 84°F near July 29.
No freezing date
Not one calendar date in the 1991–2020 record carries a normal low at or below 32°F. The coldest normal low of the year is 34°F around December 22.
Where the wet dates fall
The likeliest wet date is December 9, when 65% of years recorded at least a hundredth of an inch. The driest is July 29 at 7%. Summed across the calendar, that is about 159 wet dates a year.
The widest day
August 5 carries the biggest normal gap between afternoon and dawn, 33°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Foster Dam.
Where Foster Dam Stands Nationally
The normal water year runs well above the national norm at roughly 55 inches.
Daily temperature swings run wider than most of the country, peaking near 33°F between the normal high and low.
Foster 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: 0.1"
19.1 days with precipitation
16.8 days with precipitation
18.6 days with precipitation
17.9 days with precipitation
12.8 days with precipitation
9.2 days with precipitation
2.8 days with precipitation
3.0 days with precipitation
6.8 days with precipitation
13.1 days with precipitation
18.4 days with precipitation
20.0 days with precipitation
Foster Dam's wet season runs through the cold months
December, January and February carry 39% of the year's precipitation here, while June through August contribute 7%. That is the cool-season-dominant pattern of the West Coast and the higher inland West, where storm tracks swing south in winter and summer turns dry; the thermometer meanwhile shows an unusually narrow 26°F seasonal spread.
- Wettest month
- December, 8.4"
- Driest month
- July, 0.5"
- Wettest three months
- December, November, January (43% of the year)
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A cool-season label means the December-February share reaches 35%. Where snow falls, the monthly figures above report liquid-equivalent precipitation, so a wet winter month is not necessarily a rainy one.
How Foster Dam's precipitation splits across the calendar
About 159 days a year record measurable precipitation here, carrying 54.5" between them, or roughly 0.34 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.
Snow reaches Foster Dam, but rarely amounts to much
The normals record 0.1 inches of snow a year here, most likely in January. That is a real but marginal amount: enough that snow is part of the local record, not enough to define the winter.
A figure in this range usually reflects a handful of events that melt quickly rather than a season of accumulation.
NOAA 1991-2020 normals. An average across thirty years can smooth away a single heavy winter, so a small annual figure does not mean a significant snowfall is impossible.
Frost Dates & Growing Season
First Fall Freeze
October 28
50% probability date
Last Spring Freeze
April 12
50% probability date
Growing Season
199 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,811
Higher = more heating needed
Cooling Degree Days
233
Higher = more cooling needed
Warmest Month
July
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside OR closest to Foster 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 (52°F here).
- Auburn, NE 52°F · 0.0°F off
- Blanding, UT 52°F · 0.0°F off
- Cleveland, OH 52°F · 0.0°F off
- Cosby, MO 52°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (54.5" here), excluding temperature-peer places.
- Lebanon, TN 54.5" · 0.0" off
- McMinnville, TN 54.4" · 0.0" off
- Idabel, OK 54.5" · 0.1" off
- Bell, FL 54.4" · 0.1" off
Data-derived climate profile
How Foster Dam's climate pattern fits together
heating led · wet · low swing
Heating is the larger measured load in Foster Dam, at 4,811 degree days versus 233 for cooling. Unlike a strongly continental record, however, its 26.0°F month-to-month range is compact; persistent cool-season demand matters more than a dramatic summer-to-winter reversal.
Foster Dam's frost-free season lasts about 199 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
Foster Dam's 26.0°F seasonal spread is compact even though precipitation is abundant. July and December mark the typical warm and cold ends of the calendar. The annual average is 52°F. Temperature is relatively steady; the monthly rows show how rain and snow observations vary across the calendar.
Alongside its heating load, Foster Dam carries 54.5 inches of precipitation in a normal year, inside PlainClimate's wet range. Recorded annual snowfall is negligible. That distinction matters because a wet annual total can arrive as rain, snow, or a mixture at different times.
These labels group NOAA 1991-2020 normals from Foster Dam's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Foster Dam, not an official NOAA class or a year-ahead forecast.
Questions about Foster Dam's climate
How much rain does Foster Dam get? ▼
How much energy does heating and cooling require in Foster Dam? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Foster Dam's primary station: FOSTER DAM (USC00353047). 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 Foster 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 Foster 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.