United States · 1991–2020

Best time to visit
Arcata.

August leads for comfortable weather in Arcata: typically 18.1°C by day, 12°C at night, with 5 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortAugust

Typical high18.1°C

Typical low12°C

Rain in August5 mm

Comfort

August

August · July · September

75climate match

Beach

August

August · July · September

42climate match

Outdoors

September

September · August · June

93climate match

The weakest month is December, scoring 11 against August’s 75 — days reach only 12.9°C, 11° below the 24°C the score treats as ideal, and 205 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

1713.1° / 5.2°

Feb

2413.3° / 5.5°

Mar

2513.6° / 6.1°

Apr

3914.3° / 7.1°

May

5715.6° / 9.1°

Jun

6816.9° / 10.3°

Jul

7317.5° / 11.6°

Aug

7518.1° / 12°

Sep

7218° / 10.6°

Oct

5916.7° / 8.5°

Nov

3414.6° / 6.5°

Dec

1112.9° / 4.7°

Monthly climate evidence for Arcata — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 4 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	13.1°C	5.2°C	169 mm	14.3	11.0°C	9 h 32	17	Strong coverage
February	13.3°C	5.5°C	143 mm	12.5	10.9°C	10 h 34	24	Strong coverage
March	13.6°C	6.1°C	146 mm	13.5	10.8°C	11 h 49	25	Strong coverage
April	14.3°C	7.1°C	92 mm	10.9	11.0°C	13 h 14	39	Strong coverage
May	15.6°C	9.1°C	42 mm	6.7	11.3°C	14 h 26	57	Strong coverage
June	16.9°C	10.3°C	18 mm	3	11.7°C	15 h 05	68	Strong coverage
July	17.5°C	11.6°C	5 mm	0.8	12.3°C	14 h 50	73	Strong coverage
August	18.1°C	12°C	5 mm	1	12.9°C	13 h 48	75	Strong coverage
September	18°C	10.6°C	17 mm	2.3	12.8°C	12 h 25	72	Strong coverage
October	16.7°C	8.5°C	59 mm	5.6	12.0°C	11 h 02	59	Strong coverage
November	14.6°C	6.5°C	124 mm	11.4	11.7°C	9 h 50	34	Strong coverage
December	12.9°C	4.7°C	205 mm	14.4	11.4°C	9 h 15	11	Strong coverage

What has changed

Arcata runs +0.6°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

+0.6

Feb

-0.6

Mar

+0.1

Apr

+0.7

May

+0.7

Jun

+1.0

Jul

+0.8

Aug

+1.2

Sep

+1.1

Oct

+0.8

Nov

+0.3

Dec

+0.2

August daytime highs, 2011–2025. Last recorded: 18.5°C.

Records at EUREKA WFO WOODLEY IS, 1941–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	25.6°C12 Jan 1986	-3.9°C13 Jan 2007	94 mm17 Jan 1953	353 mm1969 · driest 17 mm in 1985	85
February	26.7°C7 Feb 1987	-2.8°C27 Feb 1962	123 mm14 Feb 1959	367 mm2019 · driest 13 mm in 2022	85
March	24.4°C31 Mar 1987	-1.1°C31 Mar 2008	74 mm17 Mar 1975	306 mm2012 · driest 12 mm in 2026	85
April	26.7°C9 Apr 1989	0.0°C6 Apr 2012	59 mm12 Apr 1963	285 mm2003 · driest 8 mm in 1956	85
May	28.3°C16 May 2008	1.7°C8 May 2002	55 mm30 May 1943	154 mm1960 · driest 1 mm in 1955	85
June	29.4°C17 Jun 1945	4.4°C8 Jun 1999	30 mm15 Jun 1954	78 mm2005 · driest 0 mm in 1945	85
July	25.0°C28 Jul 2015	7.2°C3 Jul 2018	25 mm26 Jul 1947	30 mm1947 · driest 0 mm in 1973	85
August	27.8°C30 Aug 1968	7.2°C31 Aug 2021	40 mm30 Aug 1983	87 mm1983 · driest 0 mm in 1958	84
September	30.6°C28 Sep 2020	5.0°C29 Sep 2007	66 mm24 Sep 2014	85 mm1977 · driest 0 mm in 1965	84
October	30.6°C26 Oct 1993	0.0°C29 Oct 1971	128 mm29 Oct 1950	331 mm1950 · driest 1 mm in 1978	84
November	25.6°C19 Nov 1987	-1.7°C19 Nov 1994	111 mm21 Nov 1998	421 mm1973 · driest 7 mm in 1959	84
December	25.0°C30 Dec 1963	-6.1°C9 Dec 1972	173 mm27 Dec 2002	592 mm2002 · driest 13 mm in 1976	85

Typical days per month at EUREKA WFO WOODLEY IS, 1991–2020
Month	Days 25°C+	Frost nights	Heavy rain (10 mm+)
January	0	2	6
February	0	1	5
March	0	<1	5
April	0	<1	3
May	<1	0	1
June	<1	0	<1
July	0	0	<1
August	<1	0	<1
September	<1	0	<1
October	<1	0	2
November	0	<1	4
December	0	3	7

How often, not how much — every day in EUREKA WFO WOODLEY IS’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	<1%	44%	18%	58%	10.5–14.4°C
February	2%	42%	18%	57%	11.1–15.0°C
March	1%	44%	16%	57%	11.4–14.9°C
April	2%	32%	9%	41%	12.0–15.1°C
May	3%	20%	5%	21%	13.3–16.6°C
June	3%	11%	1%	7%	14.5–17.6°C
July	6%	3%	<1%	<1%	15.2–18.4°C
August	12%	4%	<1%	2%	15.5–18.8°C
September	14%	9%	2%	7%	15.7–19.4°C
October	9%	21%	8%	27%	14.9–17.5°C
November	3%	39%	16%	56%	12.9–16.0°C
December	<1%	46%	19%	60%	10.9–14.4°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.

1942Each stripe is one year’s mean temperature against the 84-year average. Warmest: 1983. Coolest: 1955.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5558953
NOAA station: USW00024213 · EUREKA WFO WOODLEY IS
Station distance: 9.1 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 30 usable years
Daylight: Calculated from latitude 40.87°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 4 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 EUREKA WFO WOODLEY IS is what differs

Eureka→Bayside→Myrtletown→Humboldt Hill→Pine Hills→Cutten→

Or put two places side by side: Arcata vs Eureka

Best time to visitArcata.

August

August

September

The whole year,without the guesswork.

Arcata runs +0.6°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Arcata.

The whole year,
without the guesswork.

Arcata runs +0.6°C
on the 1961–1990 baseline.

Nearby, measured,
and named.