United States · 1991–2020

Best time to visit
Potomac Park.

September leads for comfortable weather in Potomac Park: typically 26.7°C by day, 12.7°C at night, with 92 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortSeptember

Typical high26.7°C

Typical low12.7°C

Rain in September92 mm

Comfort

September

September · May · June

74climate match

Beach

August

August · July · June

69climate match

Outdoors

October

October · April · May

82climate match

The weakest month is January, scoring 5 against September’s 74 — days reach only 4.9°C, 19° 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

54.9° / -5°

Feb

57.2° / -4.1°

Mar

2212.5° / -0.4°

Apr

5620.1° / 5.1°

May

7224.5° / 10.4°

Jun

6828.8° / 15.3°

Jul

5831.4° / 17.7°

Aug

6430.4° / 16.8°

Sep

7426.7° / 12.7°

Oct

6220° / 6.2°

Nov

3012.9° / 0.9°

Dec

56.7° / -2.6°

Monthly climate evidence for Potomac Park — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	4.9°C	-5°C	71 mm	7.9	9 h 39	5	Strong coverage
February	7.2°C	-4.1°C	60 mm	7.2	10 h 38	5	Strong coverage
March	12.5°C	-0.4°C	87 mm	8.8	11 h 49	22	Strong coverage
April	20.1°C	5.1°C	87 mm	9.7	13 h 11	56	Strong coverage
May	24.5°C	10.4°C	107 mm	11.6	14 h 20	72	Strong coverage
June	28.8°C	15.3°C	99 mm	10.1	14 h 57	68	Strong coverage
July	31.4°C	17.7°C	95 mm	8.5	14 h 42	58	Strong coverage
August	30.4°C	16.8°C	87 mm	8.4	13 h 43	64	Strong coverage
September	26.7°C	12.7°C	92 mm	8.2	12 h 24	74	Strong coverage
October	20°C	6.2°C	71 mm	7.4	11 h 05	62	Strong coverage
November	12.9°C	0.9°C	66 mm	6.6	9 h 56	30	Strong coverage
December	6.7°C	-2.6°C	77 mm	7.7	9 h 23	5	Strong coverage

What has changed

Potomac Park 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

+0.5

Feb

+0.2

Mar

-0.5

Apr

0.0

May

-0.9

Jun

-0.5

Jul

+0.9

Aug

-0.3

Sep

+0.3

Oct

+0.4

Nov

-0.7

Dec

+0.4

September daytime highs, 2011–2025. Last recorded: 27.0°C.

Records at CUMBERLAND 2, 1974–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	23.9°C7 Jan 2008	-25.6°C19 Jan 1994	45 mm8 Jan 1996	211 mm1996 · driest 9 mm in 1981	51
February	28.3°C21 Feb 2018	-20.6°C1 Feb 2026	56 mm6 Feb 2010	124 mm1998 · driest 8 mm in 2002	52
March	32.2°C30 Mar 1998	-16.1°C9 Mar 1984	47 mm5 Mar 1993	181 mm1993 · driest 19 mm in 2006	52
April	35.6°C18 Apr 1976	-6.7°C6 Apr 1982	45 mm16 Apr 1993	212 mm1993 · driest 22 mm in 1997	52
May	36.7°C30 May 2006	-3.9°C8 May 1977	62 mm30 May 1975	263 mm2025 · driest 27 mm in 2007	52
June	39.4°C30 Jun 2012	3.9°C8 Jun 1977	59 mm17 Jun 1989	211 mm2018 · driest 21 mm in 1990	52
July	40.6°C22 Jul 2011	7.8°C4 Jul 1979	71 mm14 Jul 2005	178 mm1989 · driest 14 mm in 1983	52
August	40.6°C20 Aug 2005	3.3°C28 Aug 1982	105 mm5 Aug 1978	204 mm1978 · driest 31 mm in 1986	51
September	38.9°C2 Sep 2010	-0.6°C30 Sep 1993	118 mm7 Sep 1996	343 mm2018 · driest 2 mm in 1985	50
October	34.4°C4 Oct 2019	-6.7°C27 Oct 1976	68 mm30 Oct 2012	206 mm1976 · driest 14 mm in 1994	50
November	30.6°C2 Nov 1982	-12.2°C30 Nov 1976	80 mm28 Nov 1993	192 mm1985 · driest 2 mm in 1998	51
December	26.7°C5 Dec 2001	-22.2°C24 Dec 1983	65 mm2 Dec 1974	148 mm2009 · driest 17 mm in 1998	52

Typical days per month at CUMBERLAND 2, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)	Snow days
January	0	0	25	3	4
February	<1	0	23	2	4
March	2	<1	17	3	2
April	8	2	4	3	<1
May	15	6	<1	4	0
June	26	13	0	4	0
July	30	21	0	3	0
August	29	19	0	3	0
September	20	8	0	3	0
October	7	1	3	2	<1
November	<1	0	14	2	<1
December	<1	0	22	3	2

The best month has moved. On the 1961–1990 numbers the strongest month here was September (scoring 82); on 2011–2025 it is May (81). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in CUMBERLAND 2’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%	25%	7%	25%	1.6–8.1°C
February	4%	25%	7%	28%	2.9–10.9°C
March	15%	28%	10%	35%	9.4–16.1°C
April	39%	32%	9%	40%	17.6–22.3°C
May	55%	37%	12%	48%	22.0–27.0°C
June	68%	31%	10%	38%	27.3–30.3°C
July	71%	30%	9%	36%	29.4–33.5°C
August	73%	27%	9%	29%	28.5–32.2°C
September	70%	26%	9%	30%	24.5–28.9°C
October	43%	24%	8%	24%	18.3–21.8°C
November	13%	23%	8%	24%	9.9–15.8°C
December	2%	25%	8%	24%	4.1–10.5°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.

1976Each stripe is one year’s mean temperature against the 48-year average. Warmest: 2006. Coolest: 1996.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4366030
NOAA station: USC00182282 · CUMBERLAND 2
Station distance: 5.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 29 usable years
Daylight: Calculated from latitude 39.61°, 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 CUMBERLAND 2 is what differs

Cumberland→Cresaptown→La Vale→Fort Ashby→Bel Air→Bowling Green→

Or put two places side by side: Potomac Park vs Cumberland

Best time to visitPotomac Park.