United States · 1991–2020

Best time to visit
Boyes Hot Springs.

May leads for comfortable weather in Boyes Hot Springs: typically 24.5°C by day, 8.8°C at night, with 27 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortMay
Typical high24.5°C
Typical low8.8°C
Rain in May27 mm
Comfort

May

May · October · June

87climate match
Beach

June

June · July · August

70climate match
Outdoors

April

April · May · October

86climate match

The weakest month is December, scoring 24 against May’s 87days reach only 14.2°C, 10° below the 24°C the score treats as ideal, and nights drop to 3.5°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
2714.5° / 3.5°
Feb
3717° / 4.5°
Mar
5219.1° / 5.5°
Apr
7321.2° / 6.7°
May
8724.5° / 8.8°
Jun
7728.8° / 10.7°
Jul
7330.6° / 12°
Aug
7230.6° / 11.8°
Sep
7329.8° / 10.6°
Oct
8325.6° / 8.6°
Nov
5819° / 5.4°
Dec
2414.2° / 3.5°
Monthly climate evidence for Boyes Hot Springs — daylight is calculated from latitude, everything else is measured
MonthDayNightRainWet daysDaylightComfortCoverage
January14.5°C3.5°C140 mm9.99 h 4627Strong coverage
February17°C4.5°C142 mm9.310 h 4237Strong coverage
March19.1°C5.5°C101 mm911 h 5052Strong coverage
April21.2°C6.7°C43 mm5.413 h 0873Strong coverage
May24.5°C8.8°C27 mm3.314 h 1487Strong coverage
June28.8°C10.7°C6 mm0.914 h 4977Strong coverage
July30.6°C12°C0 mm014 h 3573Strong coverage
August30.6°C11.8°C1 mm0.113 h 3972Strong coverage
September29.8°C10.6°C2 mm0.512 h 2373Strong coverage
October25.6°C8.6°C39 mm2.911 h 0883Strong coverage
November19°C5.4°C75 mm6.110 h 0258Strong coverage
December14.2°C3.5°C153 mm10.19 h 3124Strong coverage

What has changed

Boyes Hot Springs runs -0.8°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
+1.0
Feb
-0.4
Mar
-0.8
Apr
-0.6
May
-1.3
Jun
-1.0
Jul
-2.1
Aug
-1.8
Sep
-1.2
Oct
-0.9
Nov
-0.1
Dec
0.0
May daytime highs, 20112025. Last recorded: 26.1°C.
Records at SONOMA, 1893–2026
MonthRecord highRecord lowWettest dayWettest / driest monthYears
January28.9°C8 Jan 1962-6.7°C2 Jan 1960172 mm4 Jan 1982490 mm1995 · driest 0 mm in 201579
February36.7°C26 Feb 1894-6.7°C7 Feb 1989100 mm14 Feb 1986480 mm1998 · driest 0 mm in 202080
March32.2°C7 Mar 1894-4.4°C21 Mar 189474 mm9 Mar 1995350 mm1983 · driest 1 mm in 200778
April37.8°C28 Apr 1981-6.7°C12 Apr 189471 mm27 Apr 1953175 mm1958 · driest 0 mm in 196279
May40.6°C31 May 2001-2.8°C5 May 195242 mm27 May 199099 mm1998 · driest 0 mm in 196278
June44.4°C14 Jun 1961-0.6°C12 Jun 195246 mm2 Jun 196760 mm2011 · driest 0 mm in 198179
July46.7°C13 Jul 19721.7°C22 Jul 189426 mm8 Jul 197428 mm1974 · driest 0 mm in 201177
August42.2°C3 Aug 19982.2°C23 Aug 197925 mm20 Aug 199726 mm1997 · driest 0 mm in 201279
September43.3°C13 Sep 19711.1°C20 Sep 196569 mm18 Sep 195969 mm1959 · driest 0 mm in 201076
October41.7°C2 Oct 1980-1.1°C24 Oct 1956111 mm12 Oct 1962232 mm1962 · driest 0 mm in 199575
November32.8°C1 Nov 1985-5.6°C13 Nov 1985137 mm21 Nov 1977329 mm1973 · driest 0 mm in 195976
December26.7°C26 Dec 1967-10.6°C22 Dec 1990111 mm31 Dec 2005429 mm1955 · driest 0 mm in 198976
Typical days per month at SONOMA, 1991–2020
MonthDays 25°C+Days 30°C+Frost nightsHeavy rain (10 mm+)
January<1074
February<1035
March3<1<14
April61<11
May12501
June21110<1
July251400
August251400
September231200
October15501
November2<123
December0075
How often, not how much — every day in SONOMA’s record sorted by what it was actually like, rather than averaged
MonthWarm & dry daysWet daysWashoutsWeek with 3+ wet daysDaytime mean has ranged
January5%32%16%39%12.3–16.3°C
February23%31%16%41%15.2–19.5°C
March40%30%13%33%16.5–22.1°C
April60%18%5%17%19.3–24.1°C
May84%9%2%6%21.8–27.8°C
June96%3%<1%<1%25.8–31.3°C
July100%<1%0%0%28.9–33.6°C
August99%1%<1%<1%28.3–33.3°C
September97%3%<1%1%27.6–32.0°C
October86%10%4%10%23.4–28.3°C
November36%24%11%30%17.0–20.9°C
December4%31%15%36%12.3–16.2°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.

1952Each stripe is one year’s mean temperature against the 68-year average. Warmest: 1997. Coolest: 1954.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity
GeoNames 5330427
NOAA station
USC00048351 · SONOMA
Station distance
2.4 km from the place centre
Climate period
1991–2020
Minimum month coverage
28 usable years
Daylight
Calculated from latitude 38.31°, 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 SONOMA is what differs

Agua CalienteSonomaFetters Hot Springs-Agua CalienteEl VeranoYountvilleTemelec