Union, OR Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Union's primary NOAA station, UNION.
The climate verdict for Union
Dryness leads the climate profile for Union, Oregon, with 14.8 inches of precipitation a year. NOAA records an annual average of 49°F. At 54/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 31% of scores.
- 49°F
- average temperature, NOAA 1991-2020 normal
- 54/100
- comfort score, above 31% of station-mapped location scores
- 14.8"
- annual precipitation · 16" snow
- 138 days
- frost-free growing season
Union: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00358746 · Union, OR 49°F mean · 14.8" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 49°F
- RANK-COOL #2,470
- PHOTO-FINISH ≈ Madras
- PRCP-DRY 14.8"
- SWING-MID 37°F
- COMF-LOW 54/100
- LOAD-HEAT 6,190 HDD
- STN-1 USC00358746
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Madras, OR (+ 0 °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.
- Union (this station) 49°F
- Hot Marysvale, UT 49°F
- Near Madras, OR 49°F
- Near Condon, OR 49°F
- Near Moro, OR 49°F
Climate Living Index · Union
Union: 39/100 · grade F
Union publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Union, not an official NOAA rating. Rankings still use Comfort Score 54/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Snowfall burden | 16.2 inches/year | 54/100 · D |
| Normal heat + freeze calendar | 142 calendar days | 52/100 · D |
| Annual temperature balance | 49.0°F · 18.5° from 67.5°F | 36/100 · F |
| Precipitation balance | 14.8 in · 20.2 from 35 in | 27/100 · F |
| Frost-free season | 138 days/year | 17/100 · F |
Union · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Union is a temperate Köppen climate: Csb
Coldest-month mean 32.0°F and warmest-month mean 68.5°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
- 68.5°F
- Coldest month
- 32.0°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 Union sits across the climate record
Three NOAA fields for Union's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 36th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- Drier than 83%
- Union's annual total ranks in the drier third of 6,352 measured normals.
- Seasonal temperature swing
- Narrower than 78%
- Warmest-to-coldest month gap for Union is compact versus 6,861 complete station-years.
How Union compares across U.S. station-mapped locations
Union's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
54 31st percentile score exceeds 31% 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 | 40°F (4°C) | 25°F (-4°C) | 33°F (0°C) | 1.2" | 5.3" | 24.3 | 0.0 |
| February | 45°F (7°C) | 27°F (-3°C) | 36°F (2°C) | 0.9" | 2.9" | 19.9 | 0.0 |
| March | 53°F (11°C) | 31°F (-1°C) | 42°F (5°C) | 1.3" | 1.2" | 19.2 | 0.0 |
| April | 59°F (15°C) | 34°F (1°C) | 47°F (8°C) | 1.7" | 0.4" | 11.8 | 0.0 |
| May | 68°F (20°C) | 41°F (5°C) | 54°F (12°C) | 2.5" | 0.1" | 3.3 | 0.4 |
| June | 74°F (24°C) | 47°F (8°C) | 61°F (16°C) | 1.7" | 0.0" | 0.2 | 1.8 |
| July | 86°F (30°C) | 51°F (11°C) | 68°F (20°C) | 0.5" | 0.0" | 0.0 | 11.7 |
| August | 87°F (31°C) | 50°F (10°C) | 69°F (20°C) | 0.5" | 0.0" | 0.2 | 12.1 |
| September | 77°F (25°C) | 43°F (6°C) | 60°F (15°C) | 0.7" | 0.0" | 2.1 | 2.8 |
| October | 63°F (17°C) | 34°F (1°C) | 49°F (9°C) | 1.1" | 0.0" | 12.7 | 0.0 |
| November | 48°F (9°C) | 31°F (-1°C) | 39°F (4°C) | 1.5" | 1.4" | 16.9 | 0.0 |
| December | 39°F (4°C) | 25°F (-4°C) | 32°F (0°C) | 1.2" | 4.9" | 24.6 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 89°F around July 30, short of 90°F on every date, while 142 dates carry a normal low at or below freezing, the coldest 24°F near December 24.
The freezing stretch
The normal low stays at or below 32°F into March 25, then returns to freezing around November 5, covering 142 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 January 2, when 42% of years recorded at least a hundredth of an inch. The driest is July 25 at 12%. Summed across the calendar, that is about 114 wet dates a year.
The widest day
August 3 carries the biggest normal gap between afternoon and dawn, 38°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Union.
Where Union Stands Nationally
Day-to-night contrast is extreme by national standards — the widest normal daily swing reaches about 38°F, sharper than nine in ten ranked stations see.
A drier-than-most normal water year — around 15 inches, below what four out of five ranked stations collect.
Union 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: 5.3"
12.8 days with precipitation
Snow: 2.9"
9.5 days with precipitation
Snow: 1.2"
11.3 days with precipitation
Snow: 0.4"
12.5 days with precipitation
Snow: 0.1"
12.8 days with precipitation
9.5 days with precipitation
3.5 days with precipitation
4.0 days with precipitation
4.9 days with precipitation
8.9 days with precipitation
Snow: 1.4"
12.7 days with precipitation
Snow: 4.9"
12.1 days with precipitation
Union spreads its precipitation across the year
Neither half of the year dominates here: June through August take 18% of the annual total and December through February 23%, with neither reaching the 35% that would mark a distinct wet season. Union has no dry season to plan around, though it does carry a 36.5°F seasonal spread.
The gap between the wettest and driest month still matters: May averages 2.5" and August 0.5". The three wettest months together take 40% of the year, against the 25% a perfectly flat distribution would give them.
Shares are computed from this station's own 1991-2020 monthly precipitation normals. "Spread across the year" means neither the June-August nor the December-February share reaches 35%; it describes an average year, not the variability of any single one.
Union is dry, and what does fall arrives gently
Only about 115 days a year record measurable precipitation here, 31% of the calendar, and they carry 14.8" between them. At roughly 0.13 inches on an average wet day, this is not the damp drizzle of a marine climate; it is an arid record in which precipitation is both uncommon and light when it appears.
The wettest month by count is January at about 13 wet days; the driest is July at about 4.
A low per-event average in a dry record is a statement about typical days only. Arid regions can still take a large share of a year's total from a single convective storm, which a normal cannot show.
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, not the extremes within it.
Winter brings real snow to Union
Union averages 16.2 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 17 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: 16.2 inches of depth.
- Days recording measurable snow: about 17 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 11% 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
September 26
50% probability date
Last Spring Freeze
May 11
50% probability date
Growing Season
138 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,190
Higher = more heating needed
Cooling Degree Days
375
Higher = more cooling needed
Warmest Month
August
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside OR closest to Union 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 (49°F here).
- Altona, IL 49°F · 0.0°F off
- Burney, CA 49°F · 0.0°F off
- Cairo, NY 49°F · 0.0°F off
- Danville, OH 49°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (14.8" here), excluding temperature-peer places.
- Great Falls, MT 14.8" · 0.0" off
- Walnut Creek, AZ 14.8" · 0.0" off
- Torrington, WY 14.8" · 0.0" off
- Baker, MT 14.7" · 0.0" off
Snow and freeze rhythm
When cold and snow define Union
heating led · dry · mid swing
Union's energy balance leans toward cold weather: 6,190 annual heating degree days against 375 for cooling. Its 36.5°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 138 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. Union coldest normal
December
The monthly mean of 32°F (0°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Union typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Union snow peak
January
Union averages 16.2 inches of snow a year, with January the snowiest month on the normals.
Questions about Union's climate
How much snow does Union get? ▼
How cold does Union get in winter? ▼
How much energy does heating and cooling require in Union? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Union's primary station: UNION (USC00358746). 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 an incorporated place (GEOID 4175850). Match rule for Union: 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 Union 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.