United States · 1991–2020

Best time to visit
Fairfax.

June leads for comfortable weather in Fairfax: typically 25°C by day, 11.8°C at night, with 4 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJune

Typical high25°C

Typical low11.8°C

Rain in June4 mm

Comfort

June

June · October · July

91climate match

Beach

August

August · July · September

71climate match

Outdoors

May

May · April · October

94climate match

The weakest month is January, scoring 19 against June’s 91 — days reach only 13.2°C, 11° below the 24°C the score treats as ideal, and 193 mm of rain falls.

Month by month

The whole year,
without the guesswork.

The bars show the comfort score. Day and night temperatures come from daily observed highs and lows; rain is the historical monthly estimate.

Jan

1913.2° / 5.8°

Feb

3315.7° / 6.6°

Mar

5017.7° / 7.4°

Apr

6919.4° / 8.4°

May

8421.9° / 10.1°

Jun

9125° / 11.8°

Jul

8726.8° / 12.6°

Aug

8627° / 12.9°

Sep

8726.4° / 12.3°

Oct

8923.3° / 10.7°

Nov

5517.6° / 7.7°

Dec

2113.4° / 5.6°

Monthly climate evidence for Fairfax — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 13 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	13.2°C	5.8°C	193 mm	10.3	11.6°C	9 h 48	19	Good coverage
February	15.7°C	6.6°C	174 mm	8.9	11.9°C	10 h 43	33	Strong coverage
March	17.7°C	7.4°C	113 mm	8.4	12.0°C	11 h 50	50	Strong coverage
April	19.4°C	8.4°C	51 mm	4.6	11.5°C	13 h 08	69	Strong coverage
May	21.9°C	10.1°C	21 mm	2.4	11.7°C	14 h 12	84	Strong coverage
June	25°C	11.8°C	4 mm	0.8	12.1°C	14 h 47	91	Strong coverage
July	26.8°C	12.6°C	0 mm	0	13.4°C	14 h 33	87	Strong coverage
August	27°C	12.9°C	1 mm	0.1	14.2°C	13 h 38	86	Strong coverage
September	26.4°C	12.3°C	2 mm	0.4	14.4°C	12 h 23	87	Good coverage
October	23.3°C	10.7°C	38 mm	2.8	13.7°C	11 h 09	89	Strong coverage
November	17.6°C	7.7°C	91 mm	5.9	12.9°C	10 h 04	55	Good coverage
December	13.4°C	5.6°C	186 mm	9.7	12.0°C	9 h 32	21	Good coverage

What has changed

Fairfax runs +0.3°C
on the 1961–1990 baseline.

Each bar compares the 2011–2025 daytime average for that month against the same month in 1961–1990, measured at the same station. Months where the older record is too thin to compare are left blank.

Jan

+1.1

Feb

+0.2

Mar

-0.4

Apr

+0.2

May

-0.2

Jun

+0.3

Jul

0.0

Aug

+0.3

Sep

+0.2

Oct

+0.7

Nov

+0.2

Dec

+0.6

June daytime highs, 2011–2025. Last recorded: 27.9°C.

Records at SAN RAFAEL-CIVIC CTR, 1894–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	27.8°C9 Jan 1962	-5.0°C1 Jan 1895	190 mm21 Jan 1967	612 mm1995 · driest 0 mm in 2015	71
February	28.3°C23 Feb 2021	-6.1°C15 Feb 1993	161 mm12 Feb 1904	577 mm1998 · driest 0 mm in 1953	76
March	33.3°C20 Mar 2026	-4.4°C14 Mar 1977	101 mm19 Mar 1953	406 mm1904 · driest 0 mm in 1988	75
April	33.3°C30 Apr 1996	-2.2°C24 Apr 1894	94 mm27 Apr 1953	210 mm1958 · driest 0 mm in 1985	75
May	37.8°C13 May 1976	-2.8°C7 May 1993	51 mm18 May 1957	140 mm1957 · driest 0 mm in 1973	77
June	43.3°C15 Jun 1961	-0.6°C12 Jun 1894	50 mm2 Jun 1967	59 mm1967 · driest 0 mm in 1986	78
July	42.8°C13 Jul 1972	1.1°C2 Jul 1975	35 mm8 Jul 1974	40 mm1974 · driest 0 mm in 2011	75
August	40.6°C3 Aug 1998	4.4°C27 Aug 1992	19 mm11 Aug 1965	27 mm1997 · driest 0 mm in 2006	71
September	43.3°C1 Sep 2017	0.0°C30 Sep 1894	112 mm18 Sep 1959	156 mm1904 · driest 0 mm in 1987	76
October	42.2°C7 Oct 2024	-2.2°C28 Oct 1894	145 mm13 Oct 2009	199 mm1957 · driest 0 mm in 2013	75
November	31.1°C4 Nov 1980	-3.9°C21 Nov 1894	165 mm21 Nov 1977	475 mm1973 · driest 0 mm in 2004	76
December	26.1°C26 Dec 1967	-6.7°C22 Dec 1990	222 mm11 Dec 1995	576 mm1955 · driest 0 mm in 1989	74

Typical days per month at SAN RAFAEL-CIVIC CTR, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	<1	5
February	<1	0	<1	5
March	2	0	0	4
April	4	<1	0	2
May	8	3	0	<1
June	14	6	0	0
July	20	7	0	0
August	21	8	0	<1
September	17	8	0	0
October	11	3	0	1
November	<1	0	<1	2
December	0	0	1	5

How often, not how much — every day in SAN RAFAEL-CIVIC CTR’s record sorted by what it was actually like, rather than averaged
Month	Warm & dry days	Wet days	Washouts	Week with 3+ wet days	Daytime mean has ranged
January	3%	31%	17%	39%	11.7–15.7°C
February	16%	30%	16%	38%	13.9–18.7°C
March	30%	26%	12%	31%	15.5–20.3°C
April	50%	15%	5%	15%	17.5–22.9°C
May	70%	7%	2%	4%	20.3–25.2°C
June	90%	2%	<1%	<1%	23.2–27.8°C
July	98%	<1%	0%	0%	25.8–29.1°C
August	98%	<1%	<1%	<1%	26.0–29.0°C
September	94%	3%	<1%	2%	25.1–29.1°C
October	80%	9%	4%	9%	21.8–26.3°C
November	32%	20%	10%	26%	16.2–20.8°C
December	4%	29%	15%	36%	11.9–16.5°C

A warm and dry day reaches 20°C with under 1 mm of rain; a wet day gets 1 mm or more; a washout gets 10 mm or more. The week column is the share of seven-day stretches in that month, across the station’s whole daily record, that contained three or more wet days — the odds a week-long trip is rained on repeatedly, counted rather than modelled. The last column is the 10th to 90th percentile of that month’s daytime average across individual years: a narrow band means the average is what you will get, a wide one means the average is a midpoint between years that felt quite different.

1904Each stripe is one year’s mean temperature against the 55-year average. Warmest: 2014. Coolest: 1994.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5347322
NOAA station: USC00047880 · SAN RAFAEL-CIVIC CTR
Station distance: 4.7 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 24 usable years
Daylight: Calculated from latitude 37.99°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 13 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
Important limit: Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.

These places read the same station, so their numbers are identical — distance from SAN RAFAEL-CIVIC CTR is what differs

Novato→Lucas Valley-Marinwood→Santa Venetia→Sleepy Hollow→Lagunitas-Forest Knolls→Woodacre→

Or put two places side by side: Fairfax vs Novato

Best time to visitFairfax.

June

August

May

The whole year,without the guesswork.

Fairfax runs +0.3°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Fairfax.

The whole year,
without the guesswork.

Fairfax runs +0.3°C
on the 1961–1990 baseline.

Nearby, measured,
and named.