PlainClimate
NOAA 1991–2020 normals Incorporated place · exact Census match 1 NOAA station · Primary-station record

Fairfield, CA 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 Fairfield's primary NOAA station, FAIRFIELD.

The climate verdict for Fairfield

A compact 25.4°F seasonal swing gives Fairfield, California a steadier-than-extreme annual shape. NOAA reports an annual average of 62°F. It scores 100/100 for climate comfort (excellent), putting it in the top third of station-mapped location scores and exceeding 99% of them.

62°F
yearly average temperature, NOAA normal
100/100
comfort score, above 99% of station-mapped location scores
24.5"
annual precipitation
333 days
growing season, frost-free days

Fairfield: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.

Normals record plate

Sheet USC00042934 · Fairfield, CA 62°F mean · 24.5" precip

TEMP-MILD · RANK-UPPER · PHOTO-FINISH · PRCP-DRY · SWING-NARROW · COMF-TOP · LOAD-HEAT · STN-1 · BOOK-FULL

Nearest mean-temperature peer: Cloverdale, 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 CA station list.

Climate Living Index · Fairfield

Fairfield: 87/100 · grade A

Fairfield publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.

A
87/100Climate Living Index

PlainClimate-derived for Fairfield, not an official NOAA rating. Rankings still use Comfort Score 100/100 (separate formula). Breakpoints and limits.

Fairfield Living Index dimension scores
DimensionStation valueScore
Frost-free season 333 days/year 100/100 · A
Normal heat + freeze calendar 0 calendar days 100/100 · A
Snowfall burden 0.0 inches/year 90/100 · A
Annual temperature balance 61.7°F · 5.8° from 67.5°F 82/100 · B
Precipitation balance 24.5 in · 10.5 from 35 in 63/100 · C

Fairfield · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.

Fairfield is a temperate Köppen climate: Csa

Coldest-month mean 48.4°F and warmest-month mean 73.8°F place this station in temperate, dry-summer, hot summer climates (Csa). Class Csa is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, dry-summer, hot summer.

Köppen code
Csa
Group
Temperate
Warmest month
73.8°F
Coldest month
48.4°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 Fairfield sits across the climate record

Three NOAA fields for Fairfield's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.

Annual temperature
Top 21% warmest
Among 6,861 stations, Fairfield sits in the warmer third of annual means.
Annual precipitation
34th percentile wetness
Neither arid nor torrential versus 6,352 station totals.
Seasonal temperature swing
Narrower than 94%
Warmest-to-coldest month gap for Fairfield is compact versus 6,861 complete station-years.

How Fairfield compares across U.S. station-mapped locations

Fairfield's comfort score vs. all station-mapped locations

PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals

100 Top 1% score exceeds 99% 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%). Below this entry. 60–70: 1,236 station-mapped locations (20%). Below this entry. 70–80: 650 station-mapped locations (11%). Below this entry. 80–90: 921 station-mapped locations (15%). Below this entry. 90–100: 564 station-mapped locations (9%). This entry sits in this band. This location 0 100 every station-mapped location, bucketed by value
  1. 0–10: 0 station-mapped locations (0%). Below this entry.
  2. 10–20: 0 station-mapped locations (0%). Below this entry.
  3. 20–30: 96 station-mapped locations (2%). Below this entry.
  4. 30–40: 280 station-mapped locations (5%). Below this entry.
  5. 40–50: 1,113 station-mapped locations (18%). Below this entry.
  6. 50–60: 1,329 station-mapped locations (21%). Below this entry.
  7. 60–70: 1,236 station-mapped locations (20%). Below this entry.
  8. 70–80: 650 station-mapped locations (11%). Below this entry.
  9. 80–90: 921 station-mapped locations (15%). Below this entry.
  10. 90–100: 564 station-mapped locations (9%). This entry sits in this band.

Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020

Each bar is a band; taller bars hold more station-mapped locations. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.

Fairfield's measured station temperature trend

Methodology

Across 38 complete annual observations from 1951 to 2024, FAIRFIELD warmed at a fitted rate of 0.23°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.

Fairfield fitted annual mean temperature change, 1951-2024 Fitted station-temperature change from 1951 to 2024, relative to the fitted first year. The linear trend warmed at 0.23 °C per decade. -0.3°C +0.2°C +0.7°C +1.2°C +1.7°C 1960198020002020
  • Fairfield primary station fitted change +0.23 °C/decade
Source: NOAA GHCN-M v4, quality-controlled monthly mean temperature. PlainClimate fits ordinary least squares over complete calendar years; minimum 30 years, record must reach 2015 or later.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 57°F (14°C) 40°F (5°C) 49°F (9°C)
February 62°F (16°C) 43°F (6°C) 52°F (11°C)
March 66°F (19°C) 45°F (7°C) 56°F (13°C)
April 71°F (22°C) 48°F (9°C) 60°F (15°C)
May 78°F (25°C) 52°F (11°C) 65°F (18°C)
June 85°F (30°C) 56°F (13°C) 71°F (22°C)
July 90°F (32°C) 58°F (14°C) 74°F (23°C)
August 89°F (32°C) 58°F (14°C) 74°F (23°C)
September 87°F (31°C) 57°F (14°C) 72°F (22°C)
October 78°F (26°C) 52°F (11°C) 65°F (18°C)
November 66°F (19°C) 45°F (7°C) 55°F (13°C)
December 57°F (14°C) 40°F (5°C) 48°F (9°C)

The year, day by day

The calendar barely moves in Fairfield: no date carries a normal high of 90°F or a normal low at freezing. The year runs between 40°F near December 22 and 90°F near July 16.

Normal daily high and low temperature for Fairfield, January through December Peaks 90°F around July 16. Bottoms 40°F around December 22. 35 45 55 65 75 85 95 JanFebMarAprMayJunJulAugSepOctNovDec
Normal daily high and low across the calendar year. NOAA 1991–2020 daily normals, FAIRFIELD.

No freezing date

Not one calendar date in the 1991–2020 record carries a normal low at or below 32°F. The coldest normal low of the year is 40°F around December 22.

Where the wet dates fall

The likeliest wet date is February 18, when 36% of years recorded at least a hundredth of an inch. The driest is July 14 at 0%. Summed across the calendar, that is about 59 wet dates a year.

The widest day

July 11 carries the biggest normal gap between afternoon and dawn, 32°F between the normal high and the normal low.

Look up any date

Any date's 1991–2020 normal for Fairfield.

Monthly Precipitation

Average monthly rainfall and snowfall

January 4.7"

10.4 days with precipitation

February 5.0"

10.0 days with precipitation

March 3.3"

9.4 days with precipitation

April 1.5"

5.1 days with precipitation

May 0.7"

3.2 days with precipitation

June 0.2"

0.8 days with precipitation

July 0.0"

0.0 days with precipitation

August 0.0"

0.2 days with precipitation

September 0.1"

0.6 days with precipitation

October 1.1"

2.7 days with precipitation

November 2.5"

6.5 days with precipitation

December 5.4"

10.1 days with precipitation

Fairfield's wet season runs through the cold months

December, January and February carry 61% of the year's precipitation here, while June through August contribute 1%. 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 an unusually narrow 25.4°F seasonal spread.

Wettest month
December, 5.4"
Driest month
July, 0.0"
Wettest three months
December, February, January (61% 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.

When it rains in Fairfield, it arrives in quantity

24.5" of precipitation falls across only about 59 wet days here, averaging 0.42 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.

Days with measurable precipitation
about 59 a year, 16% of all days
Average depth per wet day
0.42 inches
Most wet days
January, about 10
Fewest wet days
July, about 0

A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.

Fairfield's record shows no measurable snowfall

This station measured snowfall across the 1991-2020 period and recorded none: the annual normal is 0.0 inches. That is a measured zero rather than missing data, which is a meaningful distinction here , most stations in the database simply do not report snow at all, and those pages say nothing about it.

A thirty-year normal of zero describes the typical year at this station. It is not a claim that snow has never fallen in the area.

Frost Dates & Growing Season

First Fall Freeze

December 14

50% probability date

Last Spring Freeze

January 15

50% probability date

Growing Season

333 days

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

2,307

Higher = more heating needed

Cooling Degree Days

1,113

Higher = more cooling needed

Warmest Month

July

Coldest Month

December

Nationwide similar cities

Other rankable U.S. places outside CA closest to Fairfield 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 (62°F here).

Closest by annual precipitation

Nearest out-of-state peers by annual precipitation (24.5" here), excluding temperature-peer places.

California climate overview →

Data-derived climate profile

How Fairfield's climate pattern fits together

heating led · moderate · low swing

Heating is the larger measured load in Fairfield, at 2,307 degree days versus 1,113 for cooling. Unlike a strongly continental record, however, its 25.4°F month-to-month range is compact; persistent cool-season demand matters more than a dramatic summer-to-winter reversal.

The frost-free window extends for about 333 days. That is a long calendar measure, but it is not a forecast and does not combine heat, rainfall, soil, or local elevation into a planting recommendation.

Temperature varies within a narrow 25.4°F band across the normal year. July and December mark the typical warm and cold ends of the calendar. The annual average is 62°F. Monthly rows still matter, but they refine a steady profile rather than reveal two climatic extremes.

Fairfield's 24.5 inches of annual precipitation falls in PlainClimate's middle band, so “wet” or “dry” is not the leading description. Recorded annual snowfall is negligible. Temperature balance and the calendar distribution carry more information than the annual moisture label alone.

These labels group NOAA 1991-2020 normals from Fairfield's primary station, so the winter figures are a thirty-year average and not a floor: a single hard season can run well below them. Treat each band as a descriptive range for Fairfield, not an official NOAA class or a year-ahead forecast.

Questions about Fairfield's climate

How much rain does Fairfield get?
Fairfield receives 24.5 inches of precipitation. Based on NOAA 30-year climate normals (1991-2020).
How many days above 90°F does Fairfield get?
Fairfield averages about 60 days a year at or above 90°F, concentrated in July and the months either side of it. That is a count of days reaching the threshold, not a measure of how far above it they go.
How much energy does heating and cooling require in Fairfield?
Fairfield has 2,307 heating degree days and 1,113 cooling degree days annually, a heating-dominated climate. Degree-day definitions: reading weather data.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Fairfield's primary station: FAIRFIELD (USC00042934). 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 0623182). Match rule for Fairfield: exact normalized name + state only, no fuzzy expansion, so nearby differently spelled facilities stay unmatched.

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate

On this page every temperature, precipitation, and derived score for Fairfield 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.