United States · 1991–2020

Best time to visit
Keystone.

June leads for comfortable weather in Keystone: typically 24.6°C by day, 8.2°C at night, with 22 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJune

Typical high24.6°C

Typical low8.2°C

Rain in June22 mm

Comfort

June

June · September · August

85climate match

Beach

August

August · July · September

71climate match

Outdoors

May

May · June · September

87climate match

The weakest month is January, scoring 5 against June’s 85 — days reach only 2.1°C, 22° 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

52.1° / -4.5°

Feb

55.5° / -3.4°

Mar

2310.5° / -1.2°

Apr

4415.4° / 1°

May

6920.6° / 5.1°

Jun

8524.6° / 8.2°

Jul

7330.4° / 11.9°

Aug

7430° / 11.8°

Sep

8524.8° / 7.9°

Oct

5016.4° / 2.5°

Nov

97.3° / -1.8°

Dec

51.8° / -4.8°

Monthly climate evidence for Keystone — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	2.1°C	-4.5°C	42 mm	8.9	8 h 52	5	Strong coverage
February	5.5°C	-3.4°C	29 mm	7	10 h 11	5	Strong coverage
March	10.5°C	-1.2°C	34 mm	7	11 h 45	23	Strong coverage
April	15.4°C	1°C	24 mm	5.5	13 h 32	44	Strong coverage
May	20.6°C	5.1°C	30 mm	5.5	15 h 03	69	Strong coverage
June	24.6°C	8.2°C	22 mm	4.2	15 h 54	85	Strong coverage
July	30.4°C	11.9°C	10 mm	1.9	15 h 34	73	Strong coverage
August	30°C	11.8°C	8 mm	1.8	14 h 14	74	Strong coverage
September	24.8°C	7.9°C	11 mm	2.6	12 h 30	85	Strong coverage
October	16.4°C	2.5°C	28 mm	5.4	10 h 47	50	Strong coverage
November	7.3°C	-1.8°C	39 mm	8.6	9 h 15	9	Strong coverage
December	1.8°C	-4.8°C	45 mm	9.4	8 h 30	5	Strong coverage

What has changed

Keystone 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

+1.0

Feb

-0.9

Mar

-0.1

Apr

-0.2

May

+0.7

Jun

-0.1

Jul

+1.2

Aug

+1.0

Sep

+0.8

Oct

-0.1

Nov

+0.6

Dec

+0.5

June daytime highs, 2011–2025. Last recorded: 27.5°C.

Records at RITZVILLE 1 SSE, 1916–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	15.6°C2 Jan 1918	-30.6°C26 Jan 1957	27 mm18 Jan 2015	106 mm2006 · driest 4 mm in 1949	110
February	18.9°C21 Feb 1995	-31.1°C1 Feb 1950	28 mm1 Feb 1963	95 mm1940 · driest 0 mm in 2005	111
March	25.0°C29 Mar 1923	-17.8°C3 Mar 1989	25 mm27 Mar 2005	78 mm2016 · driest 1 mm in 2021	109
April	33.3°C29 Apr 1926	-11.7°C20 Apr 1927	23 mm17 Apr 1925	77 mm1917 · driest 1 mm in 1924	110
May	37.2°C30 May 1983	-6.1°C1 May 2013	41 mm10 May 2005	81 mm2005 · driest 1 mm in 2021	110
June	43.3°C30 Jun 2021	-1.7°C1 Jun 1984	39 mm1 Jun 1923	101 mm1948 · driest 0 mm in 1919	111
July	43.9°C26 Jul 1928	0.6°C29 Jul 1917	44 mm23 Jul 1993	97 mm1993 · driest 0 mm in 1929	111
August	44.4°C5 Aug 1961	0.0°C29 Aug 1965	35 mm21 Aug 1959	47 mm1990 · driest 0 mm in 1955	110
September	39.4°C4 Sep 1988	-6.7°C24 Sep 1926	24 mm7 Sep 1927	115 mm1927 · driest 0 mm in 1989	108
October	33.9°C11 Oct 1934	-15.0°C31 Oct 1935	26 mm10 Oct 2016	123 mm2016 · driest 0 mm in 1987	110
November	21.1°C1 Nov 1988	-25.6°C24 Nov 1985	24 mm23 Nov 2024	107 mm1973 · driest 1 mm in 1936	109
December	16.7°C18 Dec 1917	-29.4°C12 Dec 1919	25 mm14 Dec 1977	97 mm1996 · driest 0 mm in 1916	107

Typical days per month at RITZVILLE 1 SSE, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	27	<1	5
February	0	0	24	<1	3
March	0	0	21	<1	1
April	1	0	13	<1	<1
May	6	2	4	<1	0
June	14	5	<1	<1	0
July	27	18	0	<1	0
August	27	17	0	<1	0
September	15	6	<1	<1	0
October	2	<1	9	<1	<1
November	0	0	21	<1	2
December	0	0	28	1	5

The best month has moved. On the 1961–1990 numbers the strongest month here was September (scoring 84); on 2011–2025 it is June (85). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in RITZVILLE 1 SSE’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	0%	26%	2%	29%	-3.5–4.4°C
February	0%	24%	2%	23%	1.8–8.3°C
March	3%	20%	1%	18%	8.3–13.1°C
April	20%	16%	1%	12%	13.7–18.8°C
May	53%	15%	2%	11%	18.3–23.5°C
June	78%	13%	2%	10%	22.7–28.1°C
July	94%	6%	<1%	2%	28.4–33.2°C
August	93%	6%	<1%	4%	27.5–32.1°C
September	77%	10%	1%	6%	21.5–27.9°C
October	28%	16%	2%	17%	14.6–19.6°C
November	<1%	28%	3%	35%	4.7–9.7°C
December	0%	30%	3%	37%	-0.8–4.6°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.

1917Each stripe is one year’s mean temperature against the 101-year average. Warmest: 1934. Coolest: 1985.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5799698
NOAA station: USC00457059 · RITZVILLE 1 SSE
Station distance: 21.5 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 30 usable years
Daylight: Calculated from latitude 47.24°, 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 RITZVILLE 1 SSE is what differs

Ritzville→Ashby→Carlmar→Emden→Hillcrest→Marcellus→

Or put two places side by side: Keystone vs Ritzville

Best time to visitKeystone.

June

August

May

The whole year,without the guesswork.

Keystone runs +0.4°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Keystone.

The whole year,
without the guesswork.

Keystone runs +0.4°C
on the 1961–1990 baseline.

Nearby, measured,
and named.