United States · 1991–2020

Best time to visit
Sunnyslope.

April leads for comfortable weather in Sunnyslope: typically 24.1°C by day, 9.5°C at night, with 17 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortApril

Typical high24.1°C

Typical low9.5°C

Rain in April17 mm

Comfort

April

April · November · May

90climate match

Beach

June

June · July · October

78climate match

Outdoors

January

January · December · March

91climate match

The weakest month is August, scoring 59 against April’s 90 — days average 34.9°C, 11° above 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

7120.4° / 6.3°

Feb

6820.2° / 6.5°

Mar

8222.4° / 8.1°

Apr

9024.1° / 9.5°

May

8627° / 12.5°

Jun

7830.6° / 14.9°

Jul

6134.3° / 17.7°

Aug

5934.9° / 17.8°

Sep

6733.2° / 16.3°

Oct

8228.3° / 12.8°

Nov

8723.7° / 8.4°

Dec

6719.6° / 5.8°

Monthly climate evidence for Sunnyslope — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	20.4°C	6.3°C	39 mm	3.5	10 h 07	71	Good coverage
February	20.2°C	6.5°C	51 mm	5	10 h 55	68	Good coverage
March	22.4°C	8.1°C	24 mm	3.4	11 h 52	82	Good coverage
April	24.1°C	9.5°C	17 mm	2.9	12 h 59	90	Good coverage
May	27°C	12.5°C	3 mm	0.8	13 h 55	86	Good coverage
June	30.6°C	14.9°C	1 mm	0.1	14 h 24	78	Good coverage
July	34.3°C	17.7°C	3 mm	0.4	14 h 13	61	Good coverage
August	34.9°C	17.8°C	1 mm	0.2	13 h 25	59	Good coverage
September	33.2°C	16.3°C	3 mm	0.3	12 h 21	67	Good coverage
October	28.3°C	12.8°C	9 mm	1.3	11 h 16	82	Good coverage
November	23.7°C	8.4°C	15 mm	2.4	10 h 21	87	Good coverage
December	19.6°C	5.8°C	37 mm	4.2	9 h 54	67	Good coverage

Records at RIVERSIDE MUNI AP, 1998–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	38.3°C27 Jan 2003	-4.3°C17 Jan 2007	61 mm9 Jan 2005	153 mm2005 · driest 0 mm in 2014	27
February	33.9°C27 Feb 2026	-1.1°C3 Feb 2002	68 mm14 Feb 2019	176 mm2024 · driest 0 mm in 2021	27
March	38.9°C20 Mar 2026	-1.1°C4 Mar 2002	51 mm15 Mar 2003	108 mm2023 · driest 1 mm in 2009	27
April	38.9°C26 Apr 2004	0.0°C2 Apr 1999	34 mm14 Apr 2003	67 mm2020 · driest 0 mm in 2013	28
May	40.6°C28 May 2003	3.9°C10 May 2003	11 mm4 May 2023	15 mm2015 · driest 0 mm in 2009	27
June	45.6°C20 Jun 2016	6.1°C5 Jun 1999	8 mm2 Jun 1999	8 mm1999 · driest 0 mm in 2000	27
July	47.8°C6 Jul 2018	11.1°C24 Jul 1999	34 mm19 Jul 2015	49 mm2015 · driest 0 mm in 2006	27
August	44.4°C31 Aug 2017	11.7°C31 Aug 1999	47 mm20 Aug 2023	51 mm2023 · driest 0 mm in 2008	27
September	47.2°C6 Sep 2020	9.4°C25 Sep 2005	47 mm15 Sep 2015	48 mm2015 · driest 0 mm in 2009	27
October	41.7°C1 Oct 2012	5.0°C29 Oct 2006	38 mm27 Oct 2004	65 mm2004 · driest 0 mm in 2003	27
November	37.8°C3 Nov 2010	-2.8°C30 Nov 2004	37 mm28 Nov 2019	64 mm2025 · driest 0 mm in 2021	27
December	31.7°C1 Dec 2021	-3.9°C24 Dec 1998	63 mm22 Dec 2010	175 mm2010 · driest 0 mm in 2017	27

Typical days per month at RIVERSIDE MUNI AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	7	<1	1	1
February	6	1	<1	2
March	10	3	<1	<1
April	13	5	0	<1
May	20	9	0	0
June	27	18	0	0
July	31	28	0	<1
August	31	29	0	0
September	29	23	0	0
October	22	13	0	<1
November	12	4	<1	<1
December	5	<1	1	1

How often, not how much — every day in RIVERSIDE MUNI 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	52%	12%	4%	10%	17.7–22.7°C
February	49%	17%	6%	20%	17.5–23.5°C
March	63%	12%	3%	8%	19.0–25.8°C
April	78%	8%	1%	4%	21.4–26.3°C
May	94%	3%	<1%	0%	24.7–28.8°C
June	99%	<1%	0%	0%	28.1–32.9°C
July	99%	1%	<1%	0%	32.5–36.5°C
August	99%	<1%	<1%	0%	33.9–36.5°C
September	99%	1%	<1%	0%	30.9–35.0°C
October	93%	4%	<1%	1%	25.6–31.2°C
November	76%	8%	1%	3%	21.4–25.6°C
December	47%	14%	4%	12%	17.8–22.0°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.

1999Each stripe is one year’s mean temperature against the 25-year average. Warmest: 2014. Coolest: 2001.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5400065
NOAA station: USW00003171 · RIVERSIDE MUNI AP
Station distance: 6.6 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 21 usable years
Daylight: Calculated from latitude 34.01°, 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 RIVERSIDE MUNI AP is what differs

Jurupa Valley→Glen Avon→Pedley→Home Gardens→El Cerrito Corona→Ailsa (historical)→

Or put two places side by side: Sunnyslope vs Jurupa Valley

Best time to visitSunnyslope.