United States · 1991–2020

Best time to visit
Richardson.

August leads for comfortable weather in Richardson: typically 22.6°C by day, 9.6°C at night, with 16 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortAugust

Typical high22.6°C

Typical low9.6°C

Rain in August16 mm

Comfort

August

August · July · June

86climate match

Beach

August

August · July · June

49climate match

Outdoors

June

June · September · July

95climate match

The weakest month is December, scoring 12 against August’s 86 — days reach only 7.6°C, 16° 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

138° / 2.4°

Feb

218.7° / 1.9°

Mar

3010.9° / 3°

Apr

4413.7° / 4.1°

May

5917.1° / 6.3°

Jun

7319.7° / 8.5°

Jul

8422.3° / 9.5°

Aug

8622.6° / 9.6°

Sep

7219.7° / 8.4°

Oct

4514.3° / 6.2°

Nov

2210.1° / 3.9°

Dec

127.6° / 2.2°

Monthly climate evidence for Richardson — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 9 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	8°C	2.4°C	65 mm	11.5	8.0°C	8 h 43	13	Good coverage
February	8.7°C	1.9°C	36 mm	8	7.9°C	10 h 06	21	Good coverage
March	10.9°C	3°C	33 mm	8.6	8.2°C	11 h 44	30	Good coverage
April	13.7°C	4.1°C	24 mm	5.3	8.9°C	13 h 36	44	Good coverage
May	17.1°C	6.3°C	25 mm	5.6	9.9°C	15 h 11	59	Good coverage
June	19.7°C	8.5°C	16 mm	4	11.0°C	16 h 05	73	Good coverage
July	22.3°C	9.5°C	8 mm	2.2	11.8°C	15 h 44	84	Good coverage
August	22.6°C	9.6°C	16 mm	2.4	12.1°C	14 h 20	86	Good coverage
September	19.7°C	8.4°C	24 mm	4.8	11.5°C	12 h 31	72	Good coverage
October	14.3°C	6.2°C	53 mm	8.6	10.2°C	10 h 43	45	Good coverage
November	10.1°C	3.9°C	69 mm	11.5	9.3°C	9 h 08	22	Good coverage
December	7.6°C	2.2°C	61 mm	10.9	8.5°C	8 h 20	12	Good coverage

Records at FRIDAY HARBOR AP, 1998–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	16.7°C29 Jan 2024	-12.1°C12 Jan 2024	31 mm17 Jan 2005	119 mm2002 · driest 3 mm in 2023	29
February	21.7°C27 Feb 2025	-8.2°C25 Feb 2011	44 mm15 Feb 2016	102 mm2016 · driest 9 mm in 2023	29
March	24.4°C17 Mar 2024	-7.1°C10 Mar 2009	19 mm11 Mar 2002	100 mm2026 · driest 2 mm in 2015	29
April	27.2°C25 Apr 2025	-2.7°C1 Apr 2008	20 mm1 Apr 2009	61 mm2011 · driest 0 mm in 2015	29
May	31.7°C13 May 2023	-1.1°C7 May 2002	27 mm21 May 2024	71 mm2011 · driest 0 mm in 2015	29
June	38.3°C28 Jun 2021	2.2°C1 Jun 1999	21 mm21 Jun 2025	49 mm1999 · driest 0 mm in 2015	29
July	36.1°C4 Jul 2023	4.4°C3 Jul 2000	18 mm3 Jul 1998	30 mm1998 · driest 0 mm in 2021	29
August	33.9°C12 Aug 2021	5.6°C24 Aug 2003	35 mm24 Aug 2004	89 mm2004 · driest 0 mm in 2015	28
September	31.7°C3 Sep 2017	2.2°C23 Sep 2000	15 mm28 Sep 2013	78 mm2010 · driest 0 mm in 2012	28
October	25.6°C7 Oct 2023	-3.3°C31 Oct 2003	62 mm16 Oct 2003	174 mm2003 · driest 7 mm in 2013	28
November	18.9°C8 Nov 2016	-11.0°C23 Nov 2010	48 mm15 Nov 2021	227 mm2021 · driest 11 mm in 2019	28
December	15.0°C29 Dec 2023	-13.2°C20 Dec 2008	64 mm21 Dec 2020	168 mm2025 · driest 9 mm in 2013	28

Typical days per month at FRIDAY HARBOR AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	8	2
February	0	0	9	<1
March	0	0	6	<1
April	0	0	2	<1
May	<1	0	<1	<1
June	3	<1	0	<1
July	7	1	0	0
August	7	<1	0	<1
September	2	<1	0	<1
October	0	0	<1	1
November	0	0	5	2
December	0	0	9	1

How often, not how much — every day in FRIDAY HARBOR AP’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%	36%	5%	48%	6.6–9.6°C
February	<1%	29%	2%	35%	7.0–10.8°C
March	<1%	28%	2%	35%	9.2–12.5°C
April	4%	17%	<1%	14%	12.3–15.4°C
May	20%	18%	1%	16%	15.3–19.7°C
June	43%	13%	<1%	10%	17.8–21.6°C
July	79%	7%	<1%	2%	20.3–24.9°C
August	81%	8%	2%	5%	21.5–24.4°C
September	46%	16%	2%	16%	18.5–21.2°C
October	4%	28%	4%	40%	13.4–16.1°C
November	0%	40%	7%	57%	8.9–11.5°C
December	0%	37%	5%	54%	5.8–9.0°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.

1998Each stripe is one year’s mean temperature against the 28-year average. Warmest: 2024. Coolest: 2008.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5555281
NOAA station: USW00094276 · FRIDAY HARBOR AP
Station distance: 12.1 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 22 usable years
Daylight: Calculated from latitude 48.45°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 9 km from the place centre. A sheltered bay can run warmer than the open sea it is measured from.
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 FRIDAY HARBOR AP is what differs

Friday Harbor→Argyle→Deer Harbor→Islandale→Lakedale→Lopez Island→

Or put two places side by side: Richardson vs Friday Harbor

Best time to visitRichardson.

August

August

June

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
Richardson.

The whole year,
without the guesswork.

Nearby, measured,
and named.