United States · 1991–2020

Best time to visit
Walnut.

September leads for comfortable weather in Walnut: typically 27.6°C by day, 15.1°C at night, with 123 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high27.6°C

Typical low15.1°C

Rain in September123 mm

Comfort

September

September · May · October

73climate match

Beach

July

July · August · June

75climate match

Outdoors

October

October · April · November

76climate match

The weakest month is January, scoring 5 against September’s 73 — days reach only 5.7°C, 18° below the 24°C the score treats as ideal, and nights drop to -5.2°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

55.7° / -5.2°

Feb

148.6° / -3.1°

Mar

3214.4° / 2.1°

Apr

5319.8° / 7.5°

May

6724.7° / 13.4°

Jun

5329.9° / 18.6°

Jul

5032.4° / 20.9°

Aug

5232.1° / 19.9°

Sep

7327.6° / 15.1°

Oct

6421.1° / 8.4°

Nov

3713.7° / 2.1°

Dec

97.6° / -2.9°

Monthly climate evidence for Walnut — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	5.7°C	-5.2°C	44 mm	4.7	9 h 50	5	Strong coverage
February	8.6°C	-3.1°C	47 mm	4.6	10 h 44	14	Good coverage
March	14.4°C	2.1°C	91 mm	8.4	11 h 50	32	Strong coverage
April	19.8°C	7.5°C	136 mm	9.1	13 h 07	53	Good coverage
May	24.7°C	13.4°C	184 mm	10.9	14 h 10	67	Strong coverage
June	29.9°C	18.6°C	148 mm	9.1	14 h 45	53	Good coverage
July	32.4°C	20.9°C	92 mm	7.1	14 h 31	50	Good coverage
August	32.1°C	19.9°C	104 mm	6.2	13 h 36	52	Good coverage
September	27.6°C	15.1°C	123 mm	6.3	12 h 23	73	Good coverage
October	21.1°C	8.4°C	108 mm	7.4	11 h 09	64	Good coverage
November	13.7°C	2.1°C	64 mm	5.1	10 h 06	37	Good coverage
December	7.6°C	-2.9°C	56 mm	5.2	9 h 35	9	Good coverage

What has changed

Walnut runs +0.0°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

-0.8

Mar

+0.3

Apr

-1.4

May

-0.9

Jun

+0.4

Jul

-0.1

Aug

-0.4

Sep

+0.9

Oct

-0.2

Nov

+0.2

Dec

+1.7

September daytime highs, 2011–2025. Last recorded: 28.3°C.

Records at GIRARD, 1957–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	23.3°C29 Jan 2013	-24.4°C20 Jan 1985	75 mm4 Jan 2005	148 mm2005 · driest 0 mm in 1986	68
February	28.3°C21 Feb 1996	-26.7°C16 Feb 2021	76 mm23 Feb 1985	153 mm1987 · driest 0 mm in 2006	68
March	35.0°C22 Mar 2026	-21.1°C4 Mar 2014	105 mm10 Mar 1974	290 mm1973 · driest 0 mm in 1979	67
April	36.1°C12 Apr 1972	-6.7°C12 Apr 1957	107 mm10 Apr 1994	335 mm1994 · driest 3 mm in 1989	68
May	35.6°C11 May 1963	0.0°C3 May 1976	104 mm1 May 2019	495 mm2019 · driest 35 mm in 1988	69
June	39.4°C27 Jun 1980	8.3°C1 Jun 1983	122 mm20 Jun 1967	324 mm1977 · driest 17 mm in 2020	68
July	43.3°C13 Jul 1980	10.6°C3 Jul 1959	143 mm11 Jul 1958	390 mm1992 · driest 8 mm in 1970	68
August	41.7°C3 Aug 2011	8.9°C25 Aug 1958	117 mm22 Aug 1985	259 mm2003 · driest 1 mm in 2000	69
September	41.1°C2 Sep 2000	0.0°C21 Sep 1995	237 mm24 Sep 1993	545 mm1993 · driest 13 mm in 1979	68
October	34.4°C1 Oct 1979	-7.2°C30 Oct 1993	180 mm12 Oct 1969	327 mm1986 · driest 0 mm in 1958	69
November	28.9°C9 Nov 2006	-15.0°C14 Nov 1959	91 mm20 Nov 1979	209 mm1992 · driest 0 mm in 1995	69
December	26.1°C26 Dec 2025	-27.8°C22 Dec 1989	81 mm27 Dec 2015	178 mm2015 · driest 0 mm in 1981	67

Typical days per month at GIRARD, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	26	1	1
February	<1	0	20	2	<1
March	2	<1	12	3	<1
April	7	<1	3	4	0
May	16	4	0	5	0
June	27	17	0	4	0
July	30	25	0	3	0
August	29	23	0	3	0
September	22	11	0	3	0
October	9	1	1	3	0
November	<1	0	11	3	<1
December	0	0	22	2	<1

How often, not how much — every day in GIRARD’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%	15%	5%	9%	2.4–8.8°C
February	8%	16%	6%	11%	4.6–12.6°C
March	21%	25%	10%	27%	11.0–17.6°C
April	45%	28%	13%	29%	17.9–23.0°C
May	61%	31%	16%	37%	22.9–27.6°C
June	70%	29%	15%	28%	28.3–31.9°C
July	78%	22%	10%	16%	30.6–35.2°C
August	78%	21%	10%	21%	30.1–34.6°C
September	74%	23%	12%	18%	25.5–30.4°C
October	52%	22%	11%	21%	18.9–24.3°C
November	19%	19%	9%	12%	10.2–16.8°C
December	3%	17%	7%	12%	4.4–10.8°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.

1958Each stripe is one year’s mean temperature against the 62-year average. Warmest: 2012. Coolest: 1989.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4281149
NOAA station: USC00143074 · GIRARD
Station distance: 23.5 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 21 usable years
Daylight: Calculated from latitude 37.60°, 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 GIRARD is what differs

Girard→Arma→McCune→Franklin→Hepler→Radley→

Or put two places side by side: Walnut vs Girard

Best time to visitWalnut.