Sisters, Oregon climate: Normal weather by month, frost dates and records
Sisters's normal year runs from 20°F December nights to 86°F July afternoons, with 15.2 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.5°C, December lows of −7°C, July highs of 30°C, 386 mm of precipitation a year.
- NOAA stationSisters
- Station IDUSC00357857
- Location44.28°N 121.55°W
- Elevation3,180 ft (969 m)
- Population2,957
On October 23, the normal high in Sisters is 58°F and the normal low 27°F.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Sisters.
- Jan 41° 21°
- Feb 44° 22°
- Mar 51° 25°
- Apr 57° 29°
- May 66° 34°
- Jun 74° 39°
- Jul 86° 43°
- Aug 85° 42°
- Sep 76° 36°
- Oct 61° 29°
- Nov 47° 25°
- Dec 39° 20°
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 Sisters each month?
July is the warmest month, with normal highs of 86°F; December the coldest, with normal lows of 20°F. The most precipitation falls in December (2.53 in), the least in September (0.54 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 41°F | 21°F | 30.8°F | 1.74 | – | <1 | 28 | 9 h 10 min |
| February | 44°F | 22°F | 32.9°F | 1.36 | – | <1 | 25 | 10 h 30 min |
| March | 51°F | 25°F | 37.9°F | 1.31 | – | <1 | 26 | 11 h 50 min |
| April | 57°F | 29°F | 43.0°F | 0.77 | – | <1 | 21 | 13 h 20 min |
| May | 66°F | 34°F | 50.4°F | 1.53 | – | <1 | 12 | 14 h 40 min |
| June | 74°F | 39°F | 56.6°F | 1.01 | – | 2 | 5 | 15 h 30 min |
| July | 86°F | 43°F | 64.5°F | 0.55 | – | 12 | 1 | 15 h 10 min |
| August | 85°F | 42°F | 63.5°F | 0.60 | – | 9 | 2 | 14 h 10 min |
| September | 76°F | 36°F | 55.9°F | 0.54 | – | 2 | 9 | 12 h 40 min |
| October | 61°F | 29°F | 44.9°F | 1.09 | – | <1 | 21 | 11 h |
| November | 47°F | 25°F | 35.9°F | 2.17 | – | <1 | 24 | 9 h 40 min |
| December | 39°F | 20°F | 29.6°F | 2.53 | – | <1 | 28 | 8 h 50 min |
| Year (annual) | 61°F | 30°F | 45.5°F | 15.20 | – | 25 | 202 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 5°C | −6°C | −0.7°C | 44 mm |
| February | 7°C | −6°C | 0.5°C | 35 mm |
| March | 10°C | −4°C | 3.3°C | 33 mm |
| April | 14°C | −2°C | 6.1°C | 20 mm |
| May | 19°C | 1°C | 10.2°C | 39 mm |
| June | 23°C | 4°C | 13.7°C | 26 mm |
| July | 30°C | 6°C | 18.1°C | 14 mm |
| August | 29°C | 6°C | 17.5°C | 15 mm |
| September | 24°C | 2°C | 13.3°C | 14 mm |
| October | 16°C | −2°C | 7.2°C | 28 mm |
| November | 9°C | −4°C | 2.2°C | 55 mm |
| December | 4°C | −7°C | −1.3°C | 64 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Bend (7 mi NE) (20 miles away), gets 11 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00357857; 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 Sisters?
Normal highs sit between 65°F and 85°F in May, June, August and September.
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 USC00357857.
How hot and how cold does it get in Sisters?
In a normal year in Sisters, 25 days a year reach 90°F (1 of them 100°F or more) and 202 nights fall to 32°F or colder.
- Days at 90°F or more
- 25a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 202a normal year
- Days that stay below freezing
- 16high of 32°F or less
Source: NOAA NCEI 1991-2020 annual normals, station USC00357857.
How sunny is Sisters?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Sisters, 4.3 kWh per square metre a day. July is the sunniest month (92%) and December the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 62% | 1.5 |
| February | 67% | 2.5 |
| March | 67% | 3.6 |
| April | 71% | 5.0 |
| May | 75% | 6.2 |
| June | 82% | 7.1 |
| July | 92% | 7.7 |
| August | 91% | 6.6 |
| September | 86% | 4.9 |
| October | 76% | 3.1 |
| November | 65% | 1.8 |
| December | 60% | 1.3 |
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 Sisters need?
A normal year in Sisters brings 7,246 heating degree days, 35% more than the median U.S. place (5,373), and 150 cooling degree days, 83% 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 1,450 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,060 | 0 |
| February | 899 | 0 |
| March | 840 | 0 |
| April | 662 | 0 |
| May | 456 | 2 |
| June | 265 | 14 |
| July | 87 | 71 |
| August | 102 | 54 |
| September | 282 | 9 |
| October | 622 | 0 |
| November | 872 | 0 |
| December | 1,099 | 0 |
| Year (annual) | 7,246 | 150 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00357857. 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 Sisters been warmer than normal lately?
Over 31 complete years from 1959 to 2017, the station's annual mean temperature rose at a fitted 2.0°F per century (+0.11°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Sisters's climate compare?
Sisters is warmer than 7 of the other 104 places with their own NOAA record in Oregon, and wetter than 31. Across the 7,247 U.S. stations with normals, its annual mean of 45.5°F is warmer than 21%.
In the Köppen classification computed from these normals, Sisters is Dsb: continental, 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 Sisters 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.
- Camp Sherman, OR291 people · 12 mi NW
- Black Butte Ranch, OR162 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 Sisters's climate
What is the coldest month in Sisters?
December, with a normal high of 39°F and a normal low of 20°F. The warmest is July (86°F by day, 43°F at night).
Does it snow in Sisters?
Yes. NOAA publishes no 1991-2020 snowfall normal for Sisters's NOAA station; the nearest record that keeps one, Bend (7 mi NE) (20 miles away), records 11 inches of snow in a normal year.
What is the rainiest month in Sisters?
December, with 2.53 in of precipitation in a normal year; the driest is September with 0.54 in.
What plant hardiness zone is Sisters in?
The USDA's 2023 map puts Sisters in zone 6b in ZIP code 97703, the nearest ZIP area.
Nearby and next
- Oregon climateThe statewide normals and every place in the state
- Redmond, OR21 miles from this station, 48.9°F a year
- Bend, OR21 miles from this station, 47.6°F a year
- Santiam Junction, OR22 miles from this station, 42.9°F a year
- Belknap Springs (8 mi N), OR24 miles from this station, 48.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made