United States · 1991–2020

Best time to visit
Bonny Doon.

May leads for comfortable weather in Bonny Doon: typically 25.4°C by day, 7.5°C at night, with 31 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortMay

Typical high25.4°C

Typical low7.5°C

Rain in May31 mm

Comfort

May

May · June · July

82climate match

Beach

July

July · June · August

67climate match

Outdoors

May

May · April · June

79climate match

The weakest month is December, scoring 13 against May’s 82 — 274 mm of rain falls, and days reach only 16.6°C, 7° below the 24°C the score treats as ideal.

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

1617.2° / 2.9°

Feb

2418.4° / 3.7°

Mar

4420.6° / 4.3°

Apr

7123° / 5.4°

May

8225.4° / 7.5°

Jun

7428.6° / 8.9°

Jul

7230.1° / 10.4°

Aug

6930.8° / 10.2°

Sep

6830.6° / 9.1°

Oct

7127.3° / 6.6°

Nov

5421° / 4.1°

Dec

1316.6° / 2.6°

Monthly climate evidence for Bonny Doon — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 19 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	17.2°C	2.9°C	273 mm	10.1	12.6°C	9 h 52	16	Strong coverage
February	18.4°C	3.7°C	254 mm	10.5	12.6°C	10 h 46	24	Strong coverage
March	20.6°C	4.3°C	177 mm	9.7	12.5°C	11 h 51	44	Strong coverage
April	23°C	5.4°C	82 mm	5.4	12.1°C	13 h 05	71	Strong coverage
May	25.4°C	7.5°C	31 mm	3.1	12.1°C	14 h 08	82	Strong coverage
June	28.6°C	8.9°C	5 mm	0.9	12.7°C	14 h 41	74	Strong coverage
July	30.1°C	10.4°C	0 mm	0	13.8°C	14 h 28	72	Strong coverage
August	30.8°C	10.2°C	1 mm	0.2	14.5°C	13 h 35	69	Strong coverage
September	30.6°C	9.1°C	3 mm	0.5	14.7°C	12 h 22	68	Strong coverage
October	27.3°C	6.6°C	57 mm	2.6	14.4°C	11 h 10	71	Strong coverage
November	21°C	4.1°C	128 mm	6.4	13.7°C	10 h 08	54	Strong coverage
December	16.6°C	2.6°C	274 mm	10.5	12.9°C	9 h 38	13	Strong coverage

What has changed

Bonny Doon runs +2.4°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

+2.3

Feb

+2.3

Mar

+2.4

Apr

+2.3

May

+1.6

Jun

+2.1

Jul

+1.8

Aug

+3.1

Sep

+3.4

Oct

+3.8

Nov

+2.6

Dec

+1.2

May daytime highs, 2011–2025. Last recorded: 25.7°C.

Records at BEN LOMOND #4, 1972–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	30.6°C17 Jan 2014	-6.7°C15 Jan 2007	291 mm4 Jan 1982	831 mm2017 · driest 0 mm in 2015	53
February	32.8°C9 Feb 2018	-6.7°C7 Feb 1989	133 mm17 Feb 1986	711 mm1998 · driest 2 mm in 2020	52
March	37.2°C19 Mar 2026	-3.9°C16 Mar 2016	152 mm10 Mar 2023	574 mm1983 · driest 2 mm in 1988	53
April	37.8°C30 Apr 1996	-3.9°C16 Apr 2015	96 mm11 Apr 2006	345 mm2006 · driest 1 mm in 2021	53
May	41.1°C24 May 2022	-1.1°C5 May 2015	78 mm16 May 1996	152 mm1998 · driest 0 mm in 1974	53
June	45.0°C17 Jun 2021	-0.6°C19 Jun 2015	58 mm4 Jun 2011	75 mm2011 · driest 0 mm in 1986	54
July	44.4°C22 Jul 2006	4.4°C12 Jul 1981	22 mm8 Jul 1974	42 mm1974 · driest 0 mm in 2006	54
August	45.0°C15 Aug 2020	-0.6°C26 Aug 2014	20 mm15 Aug 1976	44 mm1976 · driest 0 mm in 2018	53
September	49.4°C6 Sep 2020	-2.2°C10 Sep 2014	50 mm19 Sep 1977	63 mm1977 · driest 0 mm in 1974	53
October	44.4°C8 Oct 1996	-2.8°C21 Oct 2015	219 mm13 Oct 2009	267 mm2009 · driest 0 mm in 1978	52
November	35.6°C5 Nov 2012	-3.9°C28 Nov 2015	147 mm18 Nov 1982	419 mm1983 · driest 3 mm in 1986	53
December	29.4°C8 Dec 2020	-9.4°C23 Dec 1990	229 mm13 Dec 2021	663 mm2022 · driest 2 mm in 1989	54

Typical days per month at BEN LOMOND #4, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	3	<1	9	6
February	4	<1	6	7
March	8	2	4	5
April	11	4	1	3
May	16	6	<1	1
June	23	12	<1	<1
July	28	16	0	0
August	29	18	0	0
September	26	16	<1	<1
October	20	11	<1	1
November	7	2	5	3
December	<1	0	11	6

The best month has moved. On the 1961–1990 numbers the strongest month here was May (scoring 83); on 2011–2025 it is April (78). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in BEN LOMOND #4’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	27%	32%	18%	39%	14.4–20.6°C
February	35%	35%	22%	47%	15.6–21.9°C
March	46%	33%	18%	38%	16.5–23.9°C
April	64%	19%	8%	17%	19.8–25.3°C
May	83%	8%	3%	7%	22.3–29.2°C
June	95%	3%	<1%	<1%	25.3–31.4°C
July	99%	<1%	<1%	0%	27.5–32.5°C
August	99%	1%	<1%	<1%	27.8–33.1°C
September	96%	3%	1%	2%	27.4–33.1°C
October	85%	10%	5%	9%	24.0–30.4°C
November	51%	23%	12%	28%	17.6–23.6°C
December	24%	32%	19%	42%	14.4–20.0°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.

1973Each stripe is one year’s mean temperature against the 48-year average. Warmest: 2020. Coolest: 1994.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5330003
NOAA station: USC00040673 · BEN LOMOND #4
Station distance: 7.9 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 27 usable years
Daylight: Calculated from latitude 37.04°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 19 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 BEN LOMOND #4 is what differs

Ben Lomond→Boulder Creek→Felton→Brookdale→Lompico→Mount Hermon→

Or put two places side by side: Bonny Doon vs Ben Lomond

Best time to visitBonny Doon.

May

July

May

The whole year,without the guesswork.

Bonny Doon runs +2.4°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Bonny Doon.

The whole year,
without the guesswork.

Bonny Doon runs +2.4°C
on the 1961–1990 baseline.

Nearby, measured,
and named.