Flagstaff, AZ 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 Flagstaff's primary NOAA station, FLAGSTAFF 4 SW.
The climate verdict for Flagstaff
Flagstaff, Arizona has a mixed annual climate rather than one dominant extreme. Its NOAA normal shows an annual average of 45°F. At 44/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 10% of scores.
- 45°F
- annual average temperature (NOAA normal)
- 44/100
- comfort score, above 10% of station-mapped location scores
- 22.5"
- annual precipitation · 65" snow
- 84 days
- frost-free days per growing season
Flagstaff: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00023009 · Flagstaff, AZ 45°F mean · 22.5" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-DRY · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 45°F
- RANK-COOL #1,235
- PHOTO-FINISH ≈ Evergreen
- PRCP-DRY 22.5"
- SWING-MID 36°F
- COMF-LOW 44/100
- LOAD-HEAT 7,458 HDD
- STN-1 USC00023009
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Evergreen, CO (+ 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 AZ station list.
- Flagstaff (this station) 45°F
- Hot The Poplars, OR 45°F
- Near Evergreen, CO 45°F
- Near Brazos Lodge, NM 45°F
- Near Koosharem, UT 45°F
Climate Living Index · Flagstaff
Flagstaff: 17/100 · grade F
Flagstaff publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Flagstaff, not an official NOAA rating. Rankings still use Comfort Score 44/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Precipitation balance | 22.5 in · 12.5 from 35 in | 56/100 · C |
| Annual temperature balance | 44.7°F · 22.8° from 67.5°F | 19/100 · F |
| Snowfall burden | 65.3 inches/year | 12/100 · F |
| Frost-free season | 84 days/year | 0/100 · F |
| Normal heat + freeze calendar | 241 calendar days | 0/100 · F |
Flagstaff · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Flagstaff is a continental Köppen climate: Dsb
Coldest-month mean 28.1°F and warmest-month mean 64.2°F place this station in continental, dry-summer, warm summer climates (Dsb). Class Dsb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: continental, specifically continental, dry-summer, warm summer.
- Köppen code
- Dsb
- Group
- Continental
- Warmest month
- 64.2°F
- Coldest month
- 28.1°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 Flagstaff sits across the climate record
Three NOAA fields for Flagstaff's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- Cooler than 82%
- Among 6,861 stations, Flagstaff sits in the cooler third of annual means.
- Annual precipitation
- 31st percentile wetness
- Neither arid nor torrential versus 6,352 station totals.
- Seasonal temperature swing
- Narrower than 79%
- Warmest-to-coldest month gap for Flagstaff is compact versus 6,861 complete station-years.
How Flagstaff compares across U.S. station-mapped locations
Flagstaff's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
44 10th percentile score exceeds 10% 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%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 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 | 44°F (7°C) | 13°F (-11°C) | 28°F (-2°C) | 2.1" | 16.7" | 30.4 | 0.0 |
| February | 46°F (8°C) | 16°F (-9°C) | 31°F (-1°C) | 2.5" | 12.8" | 27.3 | 0.0 |
| March | 52°F (11°C) | 21°F (-6°C) | 36°F (2°C) | 2.3" | 13.6" | 29.6 | 0.0 |
| April | 59°F (15°C) | 25°F (-4°C) | 42°F (5°C) | 1.0" | 4.7" | 26.2 | 0.0 |
| May | 67°F (20°C) | 30°F (-1°C) | 49°F (9°C) | 0.8" | 0.5" | 21.8 | 0.0 |
| June | 78°F (26°C) | 37°F (3°C) | 57°F (14°C) | 0.4" | 0.0" | 10.0 | 0.6 |
| July | 82°F (28°C) | 47°F (8°C) | 64°F (18°C) | 2.7" | 0.0" | 0.9 | 1.7 |
| August | 79°F (26°C) | 47°F (8°C) | 63°F (17°C) | 3.3" | 0.0" | 0.3 | 0.5 |
| September | 74°F (23°C) | 38°F (4°C) | 56°F (13°C) | 1.9" | 0.0" | 7.9 | 0.0 |
| October | 64°F (18°C) | 28°F (-2°C) | 46°F (8°C) | 1.8" | 1.4" | 24.5 | 0.0 |
| November | 53°F (11°C) | 19°F (-7°C) | 36°F (2°C) | 1.5" | 5.8" | 28.2 | 0.0 |
| December | 44°F (6°C) | 13°F (-11°C) | 28°F (-2°C) | 2.2" | 9.8" | 30.3 | 0.0 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 82°F around July 8, short of 90°F on every date, while 241 dates carry a normal low at or below freezing, the coldest 12°F near December 23.
The freezing stretch
The normal low stays at or below 32°F into May 31, then returns to freezing around October 4, covering 241 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 August 8, when 47% of years recorded at least a hundredth of an inch. The driest is June 9 at 10%. Summed across the calendar, that is about 77 wet dates a year.
The widest day
June 12 carries the biggest normal gap between afternoon and dawn, 42°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Flagstaff.
Where Flagstaff Stands Nationally
Winters bite deep and often: the normal nightly low dips to freezing or below on around 241 nights a year, placing this among the most frost-prone tenth of ranked stations.
Day-to-night contrast is extreme by national standards — the widest normal daily swing reaches about 42°F, sharper than nine in ten ranked stations see.
Flagstaff 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: 16.7"
5.4 days with precipitation
Snow: 12.8"
6.1 days with precipitation
Snow: 13.6"
6.0 days with precipitation
Snow: 4.7"
4.4 days with precipitation
Snow: 0.5"
4.0 days with precipitation
2.4 days with precipitation
11.2 days with precipitation
14.2 days with precipitation
7.7 days with precipitation
Snow: 1.4"
5.5 days with precipitation
Snow: 5.8"
4.7 days with precipitation
Snow: 9.8"
4.8 days with precipitation
Flagstaff spreads its precipitation across the year
Neither half of the year dominates here: June through August take 28% of the annual total and December through February 30%, with neither reaching the 35% that would mark a distinct wet season. Flagstaff has no dry season to plan around, though it does carry a 36.1°F seasonal spread.
The gap between the wettest and driest month still matters: August averages 3.3" and June 0.4". The three wettest months together take 38% 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.
How Flagstaff's precipitation splits across the calendar
About 76 days a year record measurable precipitation here, carrying 22.5" between them, or roughly 0.29 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 Flagstaff
Flagstaff averages 65.3 inches of snowfall a year, with January the snowiest month on the normals, spread across roughly 21 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: 65.3 inches of depth.
- Days recording measurable snow: about 21 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 29% 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 15
50% probability date
Last Spring Freeze
June 23
50% probability date
Growing Season
84 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
7,458
Higher = more heating needed
Cooling Degree Days
68
Higher = more cooling needed
Warmest Month
July
Coldest Month
December
Nationwide similar cities
Other rankable U.S. places outside AZ closest to Flagstaff 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 (45°F here).
- Arlington, SD 45°F · 0.0°F off
- Buena Vista, CO 45°F · 0.0°F off
- Canby, MN 45°F · 0.0°F off
- Evergreen, CO 45°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (22.5" here), excluding temperature-peer places.
- Spur, TX 22.5" · 0.0" off
- Rio Grande City, TX 22.5" · 0.0" off
- Borger, TX 22.5" · 0.0" off
- Columbia, SD 22.5" · 0.0" off
Snow and freeze rhythm
When cold and snow define Flagstaff
heating led · moderate · mid swing
Flagstaff's energy balance leans toward cold weather: 7,458 annual heating degree days against 68 for cooling. Its 36.1°F seasonal range still makes the monthly rows more useful than the annual average alone.
Only about 84 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. Flagstaff coldest normal
December
The monthly mean of 28°F (-2°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Flagstaff typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Flagstaff snow peak
January
Flagstaff averages 65.3 inches of snow a year, with January the snowiest month on the normals.
Questions about Flagstaff's climate
How much snow does Flagstaff get? ▼
How cold does Flagstaff get in winter? ▼
How much energy does heating and cooling require in Flagstaff? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Flagstaff's primary station: FLAGSTAFF 4 SW (USC00023009). 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 0423620). Match rule for Flagstaff: 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 Flagstaff 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.