United States · 1991–2020

Best time to visit
Hidden Valley Lake.

May leads for comfortable weather in Hidden Valley Lake: typically 23.8°C by day, 7.3°C at night, with 31 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortMay

Typical high23.8°C

Typical low7.3°C

Rain in May31 mm

Comfort

May

May · October · June

85climate match

Beach

June

June · July · August

70climate match

Outdoors

May

May · April · October

83climate match

The weakest month is December, scoring 9 against May’s 85 — days reach only 13°C, 11° below the 24°C the score treats as ideal, and nights drop to 0.4°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

1113.4° / 0.2°

Feb

1814.6° / 1°

Mar

4017° / 2.1°

Apr

6119.7° / 4°

May

8523.8° / 7.3°

Jun

7728.6° / 10.6°

Jul

6533.3° / 12.9°

Aug

6632.4° / 11.8°

Sep

6930.4° / 9.6°

Oct

8324.2° / 5.8°

Nov

4417.2° / 1.8°

Dec

913° / 0.4°

Monthly climate evidence for Hidden Valley Lake — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	13.4°C	0.2°C	172 mm	11.9	9 h 43	11	Good coverage
February	14.6°C	1°C	172 mm	10.6	10 h 41	18	Good coverage
March	17°C	2.1°C	104 mm	8	11 h 50	40	Good coverage
April	19.7°C	4°C	53 mm	6.2	13 h 09	61	Good coverage
May	23.8°C	7.3°C	31 mm	3.6	14 h 16	85	Good coverage
June	28.6°C	10.6°C	6 mm	1.1	14 h 52	77	Good coverage
July	33.3°C	12.9°C	0 mm	0.1	14 h 38	65	Good coverage
August	32.4°C	11.8°C	3 mm	0.2	13 h 41	66	Good coverage
September	30.4°C	9.6°C	5 mm	0.6	12 h 23	69	Good coverage
October	24.2°C	5.8°C	28 mm	2.8	11 h 07	83	Good coverage
November	17.2°C	1.8°C	75 mm	7.2	10 h 00	44	Good coverage
December	13°C	0.4°C	184 mm	11.1	9 h 28	9	Good coverage

Records at CLEARLAKE 4 SE, 1954–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	26.7°C16 Jan 2014	-13.3°C5 Jan 1974	164 mm9 Jan 1995	659 mm1995 · driest 0 mm in 2025	56
February	27.2°C15 Feb 1977	-10.6°C17 Feb 1984	119 mm3 Feb 1998	560 mm1998 · driest 1 mm in 1971	56
March	33.9°C21 Mar 2026	-8.3°C3 Mar 1966	134 mm9 Mar 1995	399 mm1995 · driest 1 mm in 2026	58
April	34.4°C30 Apr 1981	-5.0°C24 Apr 1964	69 mm12 Apr 2006	218 mm2006 · driest 0 mm in 1964	59
May	38.3°C29 May 1984	-2.2°C18 May 1974	52 mm28 May 1990	152 mm1998 · driest 0 mm in 1959	60
June	45.6°C30 Jun 1977	1.1°C11 Jun 1972	29 mm2 Jun 1967	35 mm1967 · driest 0 mm in 2009	61
July	45.0°C16 Jul 1972	3.9°C27 Jul 1965	18 mm8 Jul 1974	18 mm1974 · driest 0 mm in 1962	59
August	44.4°C9 Aug 1978	4.4°C22 Aug 1968	31 mm18 Aug 1965	50 mm1965 · driest 0 mm in 2024	60
September	45.0°C7 Sep 2022	-1.1°C19 Sep 1965	71 mm17 Sep 1989	104 mm1989 · driest 0 mm in 1988	60
October	38.9°C3 Oct 2024	-4.4°C31 Oct 1971	78 mm23 Oct 1989	188 mm1962 · driest 0 mm in 1966	56
November	33.3°C1 Nov 1966	-7.2°C27 Nov 1956	78 mm14 Nov 1965	265 mm1983 · driest 0 mm in 2013	55
December	25.6°C16 Dec 1980	-14.4°C22 Dec 1990	160 mm12 Dec 1995	454 mm2002 · driest 0 mm in 1989	56

Typical days per month at CLEARLAKE 4 SE, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	<1	0	13	4
February	0	0	9	5
March	2	0	7	3
April	5	<1	2	1
May	13	5	0	1
June	22	12	0	<1
July	28	23	0	0
August	28	22	0	<1
September	23	16	0	0
October	15	4	<1	1
November	1	0	8	2
December	<1	0	12	5

How often, not how much — every day in CLEARLAKE 4 SE’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	6%	31%	14%	40%	10.6–15.2°C
February	14%	30%	15%	40%	12.1–17.4°C
March	29%	26%	9%	29%	13.8–19.7°C
April	51%	18%	5%	19%	16.5–23.3°C
May	77%	8%	2%	7%	21.8–27.5°C
June	94%	3%	<1%	<1%	27.5–32.0°C
July	99%	<1%	<1%	0%	31.4–36.1°C
August	99%	1%	<1%	<1%	31.3–35.8°C
September	95%	4%	<1%	3%	27.6–32.8°C
October	76%	10%	4%	9%	21.8–27.3°C
November	28%	24%	9%	32%	14.2–20.2°C
December	5%	30%	13%	38%	10.6–15.1°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.

1955Each stripe is one year’s mean temperature against the 44-year average. Warmest: 2025. Coolest: 1965.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5356767
NOAA station: USC00041806 · CLEARLAKE 4 SE
Station distance: 12.9 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 16 usable years
Daylight: Calculated from latitude 38.81°, 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 CLEARLAKE 4 SE is what differs

Clearlake→Kelseyville→Clear Lake Riviera→Lucerne→Clearlake Oaks→Middletown→

Or put two places side by side: Hidden Valley Lake vs Clearlake

Best time to visitHidden Valley Lake.

May

June

May

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Hidden Valley Lake.

The whole year,
without the guesswork.

Nearby, measured,
and named.