United States · 1991–2020

Best time to visit
Eureka.

September leads for comfortable weather in Eureka: typically 27.9°C by day, 13.8°C at night, with 99 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high27.9°C

Typical low13.8°C

Rain in September99 mm

Comfort

September

September · May · October

73climate match

Beach

August

August · July · June

70climate match

Outdoors

April

April · October · March

78climate match

The weakest month is January, scoring 5 against September’s 73 — days reach only 6.2°C, 18° below the 24°C the score treats as ideal, and nights drop to -6.8°C.

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

56.2° / -6.8°

Feb

149.1° / -4.7°

Mar

3714.9° / 0.3°

Apr

5920.1° / 5.8°

May

7124.4° / 11.9°

Jun

5929.5° / 17.4°

Jul

4932.5° / 19.8°

Aug

5532.2° / 18.6°

Sep

7327.9° / 13.8°

Oct

6821.6° / 6.8°

Nov

3614.2° / 0.2°

Dec

87.8° / -4.9°

Monthly climate evidence for Eureka — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	6.2°C	-6.8°C	25 mm	3.6	9 h 48	5	Strong coverage
February	9.1°C	-4.7°C	39 mm	4.2	10 h 44	14	Strong coverage
March	14.9°C	0.3°C	64 mm	5.4	11 h 50	37	Strong coverage
April	20.1°C	5.8°C	91 mm	6.9	13 h 07	59	Strong coverage
May	24.4°C	11.9°C	152 mm	9.2	14 h 11	71	Strong coverage
June	29.5°C	17.4°C	138 mm	7.6	14 h 46	59	Strong coverage
July	32.5°C	19.8°C	113 mm	7.1	14 h 32	49	Strong coverage
August	32.2°C	18.6°C	96 mm	6.2	13 h 37	55	Strong coverage
September	27.9°C	13.8°C	99 mm	5.8	12 h 23	73	Strong coverage
October	21.6°C	6.8°C	85 mm	5.7	11 h 09	68	Strong coverage
November	14.2°C	0.2°C	61 mm	4.4	10 h 05	36	Strong coverage
December	7.8°C	-4.9°C	42 mm	4.3	9 h 33	8	Strong coverage

What has changed

Eureka runs -0.4°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

+0.5

Feb

-0.7

Mar

-0.3

Apr

-2.1

May

-1.9

Jun

-0.1

Jul

-1.0

Aug

-0.8

Sep

+0.6

Oct

-0.4

Nov

+0.3

Dec

+1.4

September daytime highs, 2011–2025. Last recorded: 26.9°C.

Records at EUREKA 1E, 1909–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	25.6°C29 Jan 2015	-30.0°C19 Jan 1943	51 mm3 Jan 1971	85 mm2021 · driest 0 mm in 1914	107
February	30.0°C12 Feb 1962	-28.9°C11 Feb 2011	72 mm21 Feb 1997	118 mm1911 · driest 0 mm in 1991	108
March	35.0°C22 Mar 2026	-23.3°C7 Mar 1943	91 mm5 Mar 2004	230 mm1973 · driest 3 mm in 1936	104
April	37.2°C12 Apr 1972	-11.7°C3 Apr 1936	93 mm19 Apr 1927	282 mm1927 · driest 2 mm in 1989	107
May	38.3°C29 May 1913	-2.8°C1 May 1909	175 mm21 May 2019	606 mm2019 · driest 12 mm in 1994	106
June	43.3°C27 Jun 1980	4.4°C10 Jun 1913	177 mm30 Jun 2007	397 mm2007 · driest 6 mm in 1918	107
July	48.9°C18 Jul 1936	7.8°C3 Jul 1924	177 mm1 Jul 2007	395 mm2007 · driest 0 mm in 1975	109
August	46.1°C9 Aug 1936	5.6°C31 Aug 1915	151 mm24 Aug 2005	387 mm2005 · driest 6 mm in 2000	104
September	42.8°C3 Sep 2000	-2.2°C30 Sep 1984	172 mm13 Sep 1961	374 mm1961 · driest 2 mm in 1939	107
October	36.7°C5 Oct 1963	-11.7°C30 Oct 1917	133 mm11 Oct 1973	205 mm2018 · driest 5 mm in 1938	106
November	35.0°C7 Nov 1914	-17.8°C27 Nov 1975	123 mm1 Nov 1998	280 mm1998 · driest 0 mm in 1954	107
December	27.8°C24 Dec 1955	-27.8°C22 Dec 1989	72 mm26 Dec 1936	121 mm1913 · driest 0 mm in 1922	106

Typical days per month at EUREKA 1E, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	28	<1	2
February	<1	0	23	1	1
March	3	<1	16	2	<1
April	8	1	5	3	<1
May	16	4	<1	5	0
June	27	15	0	4	0
July	30	24	0	3	0
August	30	22	0	3	0
September	22	12	0	3	0
October	11	2	4	2	<1
November	2	<1	16	2	<1
December	0	0	27	2	1

The best month has moved. On the 1961–1990 numbers the strongest month here was May (scoring 76); on 2011–2025 it is September (76). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in EUREKA 1E’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	2%	13%	3%	9%	2.0–9.6°C
February	9%	15%	4%	10%	5.0–13.2°C
March	27%	18%	7%	15%	11.4–18.8°C
April	48%	23%	10%	23%	17.8–23.3°C
May	64%	29%	14%	34%	22.7–27.2°C
June	72%	28%	13%	31%	27.5–32.5°C
July	79%	21%	9%	18%	31.0–36.4°C
August	78%	22%	10%	22%	30.0–35.8°C
September	76%	22%	10%	21%	25.7–31.2°C
October	59%	18%	8%	17%	19.4–24.7°C
November	22%	14%	6%	10%	11.1–17.2°C
December	3%	13%	4%	9%	4.0–10.6°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.

1909Each stripe is one year’s mean temperature against the 85-year average. Warmest: 1931. Coolest: 2008.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4271159
NOAA station: USC00142622 · EUREKA 1E
Station distance: 2.2 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 29 usable years
Daylight: Calculated from latitude 37.82°, mid-month, sunrise to sunset including refraction. Not a station measurement.
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 1E is what differs

Hamilton→Climax→Belleview (historical)→Beaumont→Bisbee→Burkett→

Or put two places side by side: Eureka vs Hamilton

Best time to visitEureka.