United States · 1991–2020

Best time to visit
Helena Valley West Central.

June leads for comfortable weather in Helena Valley West Central: typically 23.8°C by day, 9.2°C at night, with 55 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortJune

Typical high23.8°C

Typical low9.2°C

Rain in June55 mm

Comfort

June

June · September · August

81climate match

Beach

July

July · August · June

71climate match

Outdoors

September

September · May · June

84climate match

The weakest month is January, scoring 5 against June’s 81 — days reach only 0.3°C, 24° 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

50.3° / -10.5°

Feb

52.9° / -8.5°

Mar

148.7° / -4.3°

Apr

3713.7° / 0.1°

May

6019.2° / 5°

Jun

8123.8° / 9.2°

Jul

7330.1° / 12.6°

Aug

7529.3° / 11.4°

Sep

8123° / 6.7°

Oct

4114.3° / 0.6°

Nov

56° / -5.4°

Dec

50.5° / -9.9°

Monthly climate evidence for Helena Valley West Central — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	0.3°C	-10.5°C	10 mm	3.2	8 h 56	5	Strong coverage
February	2.9°C	-8.5°C	12 mm	3.3	10 h 14	5	Strong coverage
March	8.7°C	-4.3°C	13 mm	3.5	11 h 45	14	Strong coverage
April	13.7°C	0.1°C	26 mm	5.8	13 h 30	37	Strong coverage
May	19.2°C	5°C	48 mm	7.4	14 h 59	60	Strong coverage
June	23.8°C	9.2°C	55 mm	8.5	15 h 49	81	Strong coverage
July	30.1°C	12.6°C	27 mm	5.2	15 h 29	73	Strong coverage
August	29.3°C	11.4°C	26 mm	4.5	14 h 12	75	Strong coverage
September	23°C	6.7°C	25 mm	4	12 h 29	81	Strong coverage
October	14.3°C	0.6°C	20 mm	4.2	10 h 48	41	Strong coverage
November	6°C	-5.4°C	15 mm	3.5	9 h 19	5	Strong coverage
December	0.5°C	-9.9°C	11 mm	3.2	8 h 34	5	Strong coverage

What has changed

Helena Valley West Central runs +1.3°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

+2.1

Feb

-1.6

Mar

+1.7

Apr

+0.5

May

+0.7

Jun

+1.2

Jul

+2.5

Aug

+2.1

Sep

+3.0

Oct

-0.1

Nov

+0.8

Dec

+2.3

June daytime highs, 2011–2025. Last recorded: 24.9°C.

Records at HELENA AP ASOS, 1938–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	17.2°C25 Jan 2015	-41.1°C25 Jan 1957	18 mm18 Jan 2012	71 mm1969 · driest 0 mm in 1987	88
February	20.6°C24 Feb 1995	-41.1°C2 Feb 1996	15 mm7 Feb 2024	59 mm2019 · driest 1 mm in 1991	88
March	25.6°C30 Mar 2004	-34.4°C25 Mar 1955	18 mm23 Mar 1945	41 mm1982 · driest 1 mm in 1999	88
April	30.0°C28 Apr 1939	-17.2°C2 Apr 1954	25 mm25 Apr 1975	76 mm1975 · driest 3 mm in 1977	89
May	33.9°C24 May 2001	-8.3°C2 May 1954	52 mm3 May 1964	155 mm1981 · driest 7 mm in 2014	89
June	40.0°C14 Jun 2021	-1.1°C10 Jun 1999	45 mm18 Jun 1979	120 mm1944 · driest 2 mm in 1985	89
July	40.6°C12 Jul 2002	2.2°C4 Jul 1971	35 mm30 Jul 1975	119 mm1993 · driest 0 mm in 2018	89
August	40.6°C24 Aug 1969	-2.2°C25 Aug 1992	46 mm21 Aug 1983	108 mm1974 · driest 0 mm in 2017	88
September	38.9°C7 Sep 2022	-7.8°C14 Sep 1970	41 mm11 Sep 1980	86 mm1965 · driest 0 mm in 2012	88
October	31.7°C4 Oct 2024	-22.2°C30 Oct 1991	20 mm23 Oct 1954	68 mm1975 · driest 0 mm in 2024	88
November	24.4°C5 Nov 2020	-39.4°C16 Nov 1959	22 mm8 Nov 2012	45 mm2012 · driest 0 mm in 1939	88
December	21.1°C1 Dec 2021	-38.9°C17 Dec 1964	16 mm29 Dec 2017	47 mm2017 · driest 0 mm in 2007	88

Typical days per month at HELENA AP ASOS, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	29	<1	6
February	0	0	26	<1	5
March	0	0	25	0	3
April	1	0	15	<1	2
May	6	1	3	1	<1
June	13	5	<1	2	<1
July	27	18	0	<1	0
August	26	17	0	<1	<1
September	13	4	2	<1	0
October	2	<1	14	<1	2
November	0	0	25	<1	4
December	0	0	30	<1	5

The best month has moved. On the 1961–1990 numbers the strongest month here was June (scoring 86); on 2011–2025 it is September (88). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in HELENA AP ASOS’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%	13%	<1%	9%	-5.8–3.7°C
February	<1%	12%	<1%	9%	-3.3–6.8°C
March	3%	14%	<1%	10%	2.7–11.5°C
April	16%	18%	1%	13%	10.6–16.3°C
May	38%	24%	4%	29%	16.3–21.5°C
June	60%	28%	5%	30%	20.5–26.1°C
July	82%	16%	2%	12%	26.4–31.9°C
August	82%	15%	2%	10%	25.3–30.7°C
September	62%	15%	3%	12%	18.8–26.0°C
October	23%	12%	1%	7%	12.0–17.8°C
November	<1%	11%	<1%	7%	2.4–9.7°C
December	0%	12%	<1%	9%	-3.9–4.1°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.

1939Each stripe is one year’s mean temperature against the 87-year average. Warmest: 2024. Coolest: 1951.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 7261424
NOAA station: USW00024144 · HELENA AP ASOS
Station distance: 8.5 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 30 usable years
Daylight: Calculated from latitude 46.66°, 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 HELENA AP ASOS is what differs

Helena→Helena Valley Southeast→Helena Valley Northwest→Helena Valley Northeast→Montana City→East Helena→

Or put two places side by side: Helena Valley West Central vs Helena

Best time to visitHelena Valley West Central.