Climateby Month

Pomona, CA climate by month

NOAA 1991-2020 normals · 849 ft elevation

Pomona has hot summers and mild winters. Highs peak at 95°F in August and fall to 67°F in December. The wettest month is February (about 8 wet days) and the driest is August (about 0). Snow is rare. By our comfort score the best months are March, April and May.

Warmest month
95°F
August normal high
Coldest month
44°F
December normal low
Wet days a year
45
22.5 in of precipitation
Hot days a year
93
90°F or hotter

How warm is Pomona?

Normal highs range from 67°F in December to 95°F in August.

40°60°80°100° January: normal high 68°F (20°C), low 45°F (7°C) February: normal high 68°F (20°C), low 46°F (8°C) March: normal high 72°F (22°C), low 49°F (9°C) April: normal high 76°F (24°C), low 51°F (11°C) May: normal high 80°F (27°C), low 56°F (13°C) June: normal high 86°F (30°C), low 60°F (16°C) July: normal high 94°F (34°C), low 65°F (18°C) August: normal high 95°F (35°C), low 65°F (18°C) 95° 65° September: normal high 91°F (33°C), low 64°F (18°C) October: normal high 83°F (28°C), low 57°F (14°C) November: normal high 75°F (24°C), low 49°F (9°C) December: normal high 67°F (19°C), low 44°F (7°C) 67° 44° JFMAMJJASOND

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

How rainy is Pomona?

February has the most wet days (about 8); the year brings about 23 in of precipitation.

January: 7 wet days February: 8 wet days 8 March: 7 wet days April: 4 wet days May: 4 wet days June: 2 wet days July: 1 wet days August: 0 wet days 0 September: 1 wet days October: 3 wet days November: 4 wet days December: 6 wet days JFMAMJJASOND

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

How humid is Pomona?

Humidity data is not available for this location.

How much daylight?

Daylight ranges from about 9.9 hours in December to 14.4 hours in June.

January: 10.2 hours of daylight February: 11.0 hours of daylight March: 12.0 hours of daylight April: 13.1 hours of daylight May: 13.9 hours of daylight June: 14.4 hours of daylight 14.4 July: 14.2 hours of daylight August: 13.4 hours of daylight September: 12.4 hours of daylight October: 11.3 hours of daylight November: 10.4 hours of daylight December: 9.9 hours of daylight 9.9 JFMAMJJASOND
See all numbers
Monthly climate normals and day counts for Pomona, 1991-2020
MonthHighLowPrecip.Wet daysDaylight
January 68°F45°F 5.2 in7 10.2 h
February 68°F46°F 5.7 in8 11.0 h
March 72°F49°F 3.4 in7 12.0 h
April 76°F51°F 1.3 in4 13.1 h
May 80°F56°F 0.8 in4 13.9 h
June 86°F60°F 0.2 in2 14.4 h
July 94°F65°F 0.09 in1 14.2 h
August 95°F65°F 0.0 in0 13.4 h
September 91°F64°F 0.2 in1 12.4 h
October 83°F57°F 1.1 in3 11.3 h
November 75°F49°F 1.3 in4 10.4 h
December 67°F44°F 3.3 in6 9.9 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 Pomona

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

Comfort score by month (0-100) and its parts, in days per month
MonthScoreComfortableNotable rainHot or cold
Jan 651650
Feb 621260
Mar 701741
Apr 731623
May 731625
Jun 607111
Jul 441023
Aug 421024
Sep 474118
Oct 611318
Nov 691822
Dec 641540

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 Pomona

The last spring frost typically comes around Jan 8, and the first fall frost around Dec 28, leaving 354 frost-free days in a typical year.

Frost and freeze dates for Pomona
Typical date1 year in 10
Last spring frost (32°F)Jan 8after Feb 18
First fall frost (32°F)Dec 28before Dec 5
Hard freeze (28°F)in about 7% of years; no typical date
Frost-free season354 daysunder 315 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: Pomona/Fairplex (USC00047050), NOAA 1991-2020 freeze probabilities. Frost dates for every city in California.

Hottest and coldest readings, 1991-2020

The highest reading was 118°F (September 5, 2020); the lowest was 25°F (January 14, 2007).

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

Near Pomona

Similar climates elsewhere

Where the numbers come from

  • Temperature: Ontario Intl Airport (USW00003102), 8.7 mi E of the city center, 949 ft (100 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Rain: San Gabriel Canyon PH (USC00047776), 11 mi NW of the city center, 744 ft (105 ft lower than the city). NOAA normals and daily records, 1991-2020.
  • Snowfall and snow depth: Covina City Yard Fc387b (USC00042090), 7.7 mi WNW of the city center, 607 ft (242 ft lower than the city). NOAA normals and daily records, 1991-2020.
  • Frost dates: Pomona/Fairplex (USC00047050), 2.0 mi NNW of the city center, 999 ft (150 ft higher than the city). NOAA normals and daily records, 1991-2020.
  • Humidity and wind by hour and cloud cover: Burbank Glendale Pasadena Airport (USW00023152), 36 mi WNW of the city center, 741 ft (108 ft lower than the city). NOAA normals and daily records, 1991-2020.
  • Not available for this location: daily humidity and wind (no station close enough or similar enough in elevation).

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