Prospect, OR Climate: Temperature & Rain by Month
Temperature and precipitation from NOAA NCEI 1991–2020 normals →, plus PlainClimate's derived comfort score
30-year climate normals (1991-2020) from Prospect's primary NOAA station, PROSPECT 2 SW.
The climate verdict for Prospect
Prospect, Oregon has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 53°F. Its climate comfort score of 59/100 (moderate) lands mid-pack nationally, exceeding 37% of station-mapped location scores.
- 53°F
- annual average temperature (NOAA normal)
- 59/100
- comfort score, above 37% of station-mapped location scores
- 41.3"
- annual precipitation · 21" snow
- 137 days
- frost-free days per growing season
Prospect: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00356907 · Prospect, OR 53°F mean · 41.3" precip
TEMP-COOL · RANK-MID · PHOTO-FINISH · PRCP-MID · SWING-MID · COMF-MID · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 53°F
- RANK-MID #3,568
- PHOTO-FINISH ≈ Strawberry Vall…
- PRCP-MID 41.3"
- SWING-MID 31°F
- COMF-MID 59/100
- LOAD-HEAT 4,888 HDD
- STN-1 USC00356907
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Strawberry Valley, CA ( -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.
- Prospect (this station) 53°F
- Cold Detroit Dam, OR 53°F
- Near Strawberry Vall…, CA 53°F
- Near Cascade Locks, OR 53°F
- Near Cougar, WA 53°F
Climate Living Index · Prospect
Prospect: 54/100 · grade D
Prospect publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Prospect, not an official NOAA rating. Rankings still use Comfort Score 59/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 41.3 in · 6.3 from 35 in | 78/100 · B |
| Normal heat + freeze calendar | 127 calendar days | 60/100 · C |
| Annual temperature balance | 52.7°F · 14.8° from 67.5°F | 52/100 · D |
| Snowfall burden | 20.9 inches/year | 48/100 · D |
| Frost-free season | 137 days/year | 17/100 · F |
Prospect · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Prospect is a temperate Köppen climate: Csb
Coldest-month mean 38.8°F and warmest-month mean 69.5°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
- 69.5°F
- Coldest month
- 38.8°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 Prospect sits across the climate record
Three NOAA fields for Prospect's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 52nd percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- 61st percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Narrower than 90%
- Warmest-to-coldest month gap for Prospect is compact versus 6,861 complete station-years.
How Prospect compares across U.S. station-mapped locations
Prospect's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
59 37th percentile score exceeds 37% 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%). This entry sits in this band.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 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
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 50°F (10°C) | 30°F (-1°C) | 40°F (5°C) | 6.0" | 7.6" | 21.1 | 0.0 |
| February | 54°F (12°C) | 31°F (-1°C) | 42°F (6°C) | 4.4" | 3.1" | 18.3 | 0.0 |
| March | 58°F (14°C) | 33°F (0°C) | 45°F (7°C) | 4.4" | 2.3" | 17.5 | 0.0 |
| April | 62°F (17°C) | 35°F (2°C) | 49°F (9°C) | 3.7" | 1.0" | 11.0 | 0.0 |
| May | 71°F (22°C) | 41°F (5°C) | 56°F (13°C) | 2.6" | 0.0" | 3.8 | 1.1 |
| June | 78°F (26°C) | 45°F (7°C) | 62°F (16°C) | 1.3" | 0.0" | 0.5 | 3.0 |
| July | 89°F (32°C) | 50°F (10°C) | 70°F (21°C) | 0.6" | 0.0" | 0.0 | 13.9 |
| August | 89°F (32°C) | 49°F (10°C) | 69°F (21°C) | 0.5" | 0.0" | 0.0 | 15.0 |
| September | 84°F (29°C) | 44°F (7°C) | 64°F (18°C) | 1.2" | 0.0" | 0.8 | 8.9 |
| October | 70°F (21°C) | 38°F (3°C) | 54°F (12°C) | 3.3" | 0.0" | 7.4 | 0.8 |
| November | 55°F (13°C) | 34°F (1°C) | 44°F (7°C) | 6.3" | 2.9" | 14.4 | 0.0 |
| December | 48°F (9°C) | 30°F (-1°C) | 39°F (4°C) | 7.2" | 4.0" | 21.3 | 0.0 |
The year, day by day
Prospect works both ends of the calendar. Normal highs climb to 91°F by July 27 and hold at or above 90°F on 25 dates, then normal lows drop to freezing or below on 102 dates, bottoming at 29°F around December 23.
When the heat sits
Normal highs reach 90°F from July 19 through August 12, covering 25 dates. The broader mild season, normal highs of 70°F or more, runs May 11 to October 16.
This counts calendar dates whose 1991–2020 normal high reaches 90°F. It is a smaller number than the 90°F+ day counts in the monthly table above, which measure how often the threshold was actually crossed in a typical year. A date can average 88°F and still exceed 90°F in half of all years.
The freezing stretch
The normal low stays at or below 32°F into March 8, then returns to freezing around November 28, covering 102 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is November 25, when 58% of years recorded at least a hundredth of an inch. The driest is August 5 at 6%. Summed across the calendar, that is about 130 wet dates a year.
The widest day
September 4 carries the biggest normal gap between afternoon and dawn, 41°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Prospect.
Where Prospect Stands Nationally
Day-to-night contrast is extreme by national standards — the widest normal daily swing reaches about 41°F, sharper than nine in ten ranked stations see.
Prospect earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 7.6"
16.4 days with precipitation
Snow: 3.1"
14.4 days with precipitation
Snow: 2.3"
16.0 days with precipitation
Snow: 1.0"
14.9 days with precipitation
10.8 days with precipitation
5.1 days with precipitation
2.4 days with precipitation
2.0 days with precipitation
3.8 days with precipitation
9.0 days with precipitation
Snow: 2.9"
17.3 days with precipitation
Snow: 4.0"
17.3 days with precipitation
Prospect's wet season runs through the cold months
December, January and February carry 43% of the year's precipitation here, while June through August contribute 6%. 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 a 30.7°F seasonal spread.
- Wettest month
- December, 7.2"
- Driest month
- August, 0.5"
- Wettest three months
- December, November, January (47% 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 Prospect's precipitation splits across the calendar
About 129 days a year record measurable precipitation here, carrying 41.3" between them, or roughly 0.32 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.
Winter brings real snow to Prospect
Prospect averages 20.9 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 9 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 20.9 inches of depth.
- Days recording measurable snow: about 9 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 5% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
Frost Dates & Growing Season
First Fall Freeze
October 3
50% probability date
Last Spring Freeze
May 19
50% probability date
Growing Season
137 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
4,888
Higher = more heating needed
Cooling Degree Days
434
Higher = more cooling needed
Warmest Month
July
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside OR closest to Prospect 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 (53°F here).
- Belleville, KS 53°F · 0.0°F off
- Cambridge, OH 53°F · 0.0°F off
- Cheyenne Wells, CO 53°F · 0.0°F off
- Cubero, NM 53°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (41.3" here), excluding temperature-peer places.
- Holdenville, OK 41.3" · 0.0" off
- Mattoon, IL 41.3" · 0.0" off
- Wooster, OH 41.3" · 0.0" off
- Rockville, MD 41.3" · 0.0" off
Snow and freeze rhythm
When cold and snow define Prospect
heating led · moderate · mid swing
Prospect's energy balance leans toward cold weather: 4,888 annual heating degree days against 434 for cooling. Its 30.7°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 137 days are frost-free in a normal year. That short interval is consistent with the cold-season signal, but the measure does not predict the exact first or last freeze in any one year.
-
1. Prospect coldest normal
December
The coldest month still averages 39°F (4°C), above freezing, so this calendar has no hard winter.
-
2. Prospect typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Prospect snow peak
January
Prospect averages 20.9 inches of snow a year, with January the snowiest month on the normals.
Questions about Prospect's climate
How much snow does Prospect get? ▼
How many days above 90°F does Prospect get? ▼
How much energy does heating and cooling require in Prospect? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Prospect's primary station: PROSPECT 2 SW (USC00356907). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The 2024 Census Gazetteer identifies the exact name-and-state match as a census-designated place (GEOID 4160100), not an incorporated municipality. Match rule for Prospect: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.
On this page every temperature, precipitation, and derived score for Prospect 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.