Alsea, Oregon climate: Normal weather by month, frost dates and records
Alsea's normal year runs from 35°F December nights to 76°F August afternoons, with 91.9 inches of precipitation and less than an inch of snow (0.8 in) a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.2°C, December lows of 2°C, August highs of 24°C, 2,334 mm of precipitation a year.
- NOAA stationAlsea Fh (Fall Creek)
- Station IDUSC00350145
- Location44.40°N 123.75°W
- Elevation230 ft (70 m)
- Population (census place)129
On October 14, the normal high in Alsea is 59°F and the normal low 43°F, and the chance of measurable rain or snow is 47%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Alsea.
- Jan 45° 36°
- Feb 49° 36°
- Mar 53° 37°
- Apr 58° 39°
- May 64° 44°
- Jun 69° 47°
- Jul 75° 49°
- Aug 76° 50°
- Sep 69° 46°
- Oct 59° 42°
- Nov 50° 39°
- Dec 44° 35°
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 Alsea each month?
August is the warmest month, with normal highs of 76°F; December the coldest, with normal lows of 35°F. The most precipitation falls in December (16.39 in), the least in July (0.52 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 45°F | 36°F | 40.6°F | 14.63 | 21 | <1 | 10 | 9 h 10 min |
| February | 49°F | 36°F | 42.4°F | 10.77 | 18 | <1 | 10 | 10 h 30 min |
| March | 53°F | 37°F | 44.8°F | 10.80 | 21 | <1 | 9 | 11 h 50 min |
| April | 58°F | 39°F | 48.3°F | 7.71 | 18 | <1 | 3 | 13 h 20 min |
| May | 64°F | 44°F | 53.6°F | 4.06 | 13 | <1 | <1 | 14 h 50 min |
| June | 69°F | 47°F | 57.7°F | 2.55 | 10 | <1 | <1 | 15 h 30 min |
| July | 75°F | 49°F | 62.0°F | 0.52 | 4 | 1 | <1 | 15 h 10 min |
| August | 76°F | 50°F | 62.6°F | 0.80 | 4 | 1 | <1 | 14 h 10 min |
| September | 69°F | 46°F | 57.8°F | 2.68 | 9 | <1 | <1 | 12 h 40 min |
| October | 59°F | 42°F | 50.5°F | 7.32 | 15 | <1 | 3 | 11 h |
| November | 50°F | 39°F | 44.3°F | 13.67 | 20 | <1 | 5 | 9 h 40 min |
| December | 44°F | 35°F | 39.8°F | 16.39 | 21 | <1 | 12 | 8 h 50 min |
| Year (annual) | 59°F | 42°F | 50.4°F | 91.90 | 174 | 2 | 53 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 7°C | 2°C | 4.8°C | 372 mm |
| February | 9°C | 2°C | 5.8°C | 274 mm |
| March | 12°C | 3°C | 7.1°C | 274 mm |
| April | 14°C | 4°C | 9.1°C | 196 mm |
| May | 18°C | 6°C | 12.0°C | 103 mm |
| June | 20°C | 8°C | 14.3°C | 65 mm |
| July | 24°C | 9°C | 16.7°C | 13 mm |
| August | 24°C | 10°C | 17.0°C | 20 mm |
| September | 21°C | 8°C | 14.3°C | 68 mm |
| October | 15°C | 6°C | 10.3°C | 186 mm |
| November | 10°C | 4°C | 6.8°C | 347 mm |
| December | 7°C | 2°C | 4.3°C | 416 mm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00350145; 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 Alsea?
Normal highs sit between 65°F and 85°F in June, July, August and September. Of those, July has the fewest days with rain (4).
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 USC00350145.
When is the last frost in Alsea?
In Alsea, the last spring frost (32°F) comes after April 13 in half of years and after May 3 in one year in ten; the first autumn frost comes before November 3 in half of years and before October 9 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 131 year in 10 after May 3; 9 in 10 after March 17
- First autumn frost, half of years before
- November 31 year in 10 before October 9; 9 in 10 before December 3
NOAA puts the median frost-free season at 202 days, and the season without a hard freeze (28°F) at 272 days.
A hard freeze (28°F) comes after February 28 in half of springs and before November 28 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Alsea in zone 8b in ZIP code 97324, the nearest ZIP area.
Frost dates for every NOAA station in Oregon · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00350145; 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 in Alsea?
In a normal year in Alsea, 2 days a year reach 90°F, 53 nights fall to 32°F or colder and 174 days bring measurable precipitation.
- Days at 90°F or more
- 2a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 53a normal year
- Days that stay below freezing
- 2high of 32°F or less
- Days with 0.01 inch of precipitation
- 174a normal year
Source: NOAA NCEI 1991-2020 annual normals, station USC00350145.
How sunny is Alsea?
Over a year 73% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Alsea, 3.9 kWh per square metre a day. July is the sunniest month (87%) and December the cloudiest (54%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 57% | 1.3 |
| February | 61% | 2.2 |
| March | 61% | 3.2 |
| April | 66% | 4.5 |
| May | 71% | 5.7 |
| June | 74% | 6.3 |
| July | 87% | 7.1 |
| August | 86% | 6.1 |
| September | 81% | 4.5 |
| October | 70% | 2.8 |
| November | 59% | 1.5 |
| December | 54% | 1.1 |
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 Alsea need?
A normal year in Alsea brings 5,379 heating degree days, 0% more than the median U.S. place (5,373), and 51 cooling degree days, 94% 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 1,498 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 756 | 0 |
| February | 633 | 0 |
| March | 625 | 0 |
| April | 503 | 0 |
| May | 355 | 2 |
| June | 227 | 6 |
| July | 115 | 20 |
| August | 96 | 20 |
| September | 220 | 3 |
| October | 448 | 0 |
| November | 620 | 0 |
| December | 783 | 0 |
| Year (annual) | 5,379 | 51 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00350145. 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 Alsea been warmer than normal lately?
2024 averaged 50.5°F, 0.1°F above the 1991-2020 normal of 50.4°F. 2 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 51.0°F | +0.6°F | 91.18 |
| 2022 | 49.8°F | −0.6°F | 90.93 |
| 2023 | 50.4°F | at normal | 88.07 |
| 2024 | 50.5°F | +0.1°F | 98.65 |
Source: observed years: ACIS, station USC00350145. A year counts only with all twelve months complete.
How does Alsea's climate compare?
Alsea is warmer than 37 of the other 104 places with their own NOAA record in Oregon, and wetter than 95. Across the 7,247 U.S. stations with normals, its annual mean of 50.4°F is warmer than 42%.
In the Köppen classification computed from these normals, Alsea 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.
Questions about Alsea's climate
What is the coldest month in Alsea?
December, with a normal high of 44°F and a normal low of 35°F. The warmest is August (76°F by day, 50°F at night).
Does it snow in Alsea?
Rarely: NOAA's normal is 0.8 inch a year.
What is the rainiest month in Alsea?
December, with 16.39 in of precipitation in a normal year; the driest is July with 0.52 in.
What plant hardiness zone is Alsea in?
The USDA's 2023 map puts Alsea in zone 8b in ZIP code 97324, the nearest ZIP area.
How late can frost come in Alsea?
In half of years the last 32°F night comes after April 13; in one year in ten it comes after May 3. Waiting until May 3 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Oregon climateThe statewide normals and every place in the state
- Yachats, OR18 miles from this station, 52.3°F a year
- Newport, OR22 miles from this station, 50.6°F a year
- Mapleton, OR26 miles from this station, 55.6°F a year
- Fern Ridge-Veneta, OR31 miles from this station, 52.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made