Climateby Month

Flagstaff, AZ climate by month

NOAA 1991-2020 normals · 6,900 ft elevation

Flagstaff has warm summers and chilly and snowy winters. Highs peak at 82°F in July and fall to 43°F in December. The wettest month is August (about 13 wet days) and the driest is June (about 2). Normal snowfall is about 90 in a year. By our comfort score the best months are May and September.

Warmest month
82°F
July normal high
Coldest month
17°F
December normal low
Wet days a year
82
20.5 in of precipitation
Snow a year
90.1 in
normal snowfall

How warm is Flagstaff?

Normal highs range from 43°F in December to 82°F in July.

0°20°40°60°80°100° January: normal high 43°F (6°C), low 18°F (-8°C) 43° 18° February: normal high 46°F (8°C), low 20°F (-7°C) March: normal high 52°F (11°C), low 24°F (-4°C) April: normal high 59°F (15°C), low 28°F (-2°C) May: normal high 68°F (20°C), low 35°F (2°C) June: normal high 79°F (26°C), low 43°F (6°C) July: normal high 82°F (28°C), low 51°F (11°C) 82° 51° August: normal high 79°F (26°C), low 51°F (11°C) September: normal high 74°F (23°C), low 43°F (6°C) October: normal high 64°F (18°C), low 32°F (0°C) November: normal high 52°F (11°C), low 23°F (-5°C) December: normal high 43°F (6°C), low 17°F (-8°C) JFMAMJJASOND

Bars run from the normal low to the normal high for each month.

How rainy is Flagstaff?

August has the most wet days (about 13); the year brings about 21 in of precipitation.

January: 7 wet days February: 8 wet days March: 7 wet days April: 5 wet days May: 5 wet days June: 2 wet days 2 July: 12 wet days August: 13 wet days 13 September: 8 wet days October: 5 wet days November: 4 wet days December: 7 wet days JFMAMJJASOND

Wet day: at least 0.01 in of rain or melted snow, counted from daily records 1991-2020.

How much does it snow?

Normal snowfall is 90.1 in a year, most of it in January.

January: 20.9 in of snow 20.9 February: 19.3 in of snow March: 15.6 in of snow April: 5.0 in of snow May: 1.1 in of snow June: 0.0 in of snow 0.0 July: 0.0 in of snow August: 0.0 in of snow September: 0.0 in of snow October: 1.5 in of snow November: 8.2 in of snow December: 18.5 in of snow JFMAMJJASOND

How humid is Flagstaff?

Humidity data is not available for this location.

How much daylight?

Daylight ranges from about 9.8 hours in December to 14.5 hours in June.

January: 10.1 hours of daylight February: 10.9 hours of daylight March: 12.0 hours of daylight April: 13.1 hours of daylight May: 14.0 hours of daylight June: 14.5 hours of daylight 14.5 July: 14.3 hours of daylight August: 13.4 hours of daylight September: 12.4 hours of daylight October: 11.3 hours of daylight November: 10.3 hours of daylight December: 9.8 hours of daylight 9.8 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Flagstaff, 1991-2020
MonthHighLowPrecip.Wet daysSnowDaylight
January 43°F18°F 2.0 in7 20.9 in 10.1 h
February 46°F20°F 2.2 in8 19.3 in 10.9 h
March 52°F24°F 1.9 in7 15.6 in 12.0 h
April 59°F28°F 0.9 in5 5.0 in 13.1 h
May 68°F35°F 0.8 in5 1.1 in 14.0 h
June 79°F43°F 0.3 in2 0.0 in 14.5 h
July 82°F51°F 2.6 in12 0.0 in 14.3 h
August 79°F51°F 3.0 in13 0.0 in 13.4 h
September 74°F43°F 1.8 in8 0.0 in 12.4 h
October 64°F32°F 1.5 in5 1.5 in 11.3 h
November 52°F23°F 1.6 in4 8.2 in 10.3 h
December 43°F17°F 1.9 in7 18.5 in 9.8 h

High and low: NOAA 1991-2020 normal daily high and low. Wet days: at least 0.01 in of rain or melted snow. Muggy days: daily mean dew point 65°F or higher.

Best months to visit Flagstaff

By our comfort score, the best months are May and September.

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 360412
Feb 40059
Mar 49244
Apr 65921
May 822020
Jun 771511
Jul 671162
Aug 721771
Sep 822440
Oct 691631
Nov 47334
Dec 360413

Score = 40 × share of comfortable days + 25 × share of days without notable rain + 20 × share of days neither hot (90°F+) nor cold (high 40°F or below) + 15 × daylight. Comfortable days here are judged by temperature only (no humidity station nearby). How the score works.

Frost dates in Flagstaff

The last spring frost typically comes around Jun 4, and the first fall frost around Sep 28, leaving 115 frost-free days in a typical year.

Frost and freeze dates for Flagstaff
Typical date1 year in 10
Last spring frost (32°F)Jun 4after Jun 19
First fall frost (32°F)Sep 28before Sep 16
Last hard freeze (28°F)May 20after Jun 6
First hard freeze (28°F)Oct 9before Sep 28
Frost-free season115 daysunder 96 days

"Typical" is the date with a 50% chance of a later spring frost (or earlier fall frost). Planting after the "1 year in 10" spring date gives a 90% chance of no further frost. The Old Farmer's Almanac publishes 30% dates, which fall between our typical and 1-in-10 dates.

Station: Flagstaff Pulliam Airport (USW00003103), NOAA 1991-2020 freeze probabilities. Frost dates for every city in Arizona.

Hottest and coldest readings, 1991-2020

The highest reading was 96°F (June 28, 2013); the lowest was -19°F (January 1, 2011).

From the temperature station's daily records with NOAA quality flags removed. Not an all-time record.

Near Flagstaff

Similar climates elsewhere

Where the numbers come from

  • Temperature, rain, snowfall and frost dates: Flagstaff Pulliam Airport (USW00003103), 3.8 mi SSW of the city center, 7,003 ft (103 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Snow depth: Sunset Crater Nm (USC00028329), 13 mi NNE of the city center, 6,980 ft (80 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour: Grand Canyon NP Airport (USW00003195), 59 mi NNW of the city center, 6,606 ft (294 ft lower than the city). NOAA normals and daily records, 1991-2020.
  • Not available for this location: cloud cover and daily humidity and wind (no station close enough or similar enough in elevation).

Distances from the city center (USGS). Methodology · Report an error