United States · 1991–2020

Best time to visit
South Whittier.

May leads for comfortable weather in South Whittier: typically 24.5°C by day, 14.6°C at night, with 7 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortMay

Typical high24.5°C

Typical low14.6°C

Rain in May7 mm

Comfort

May

May · April · November

98climate match

Beach

July

July · August · September

93climate match

Outdoors

March

March · December · January

92climate match

The weakest month is December, scoring 71 against May’s 98 — nights drop to 7.5°C, and days reach only 20.3°C, 4° 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

7421° / 8°

Feb

7220.7° / 8.7°

Mar

8522° / 10.6°

Apr

9223.2° / 12°

May

9824.5° / 14.6°

Jun

8926.4° / 16.8°

Jul

7529.4° / 18.8°

Aug

7230.4° / 19°

Sep

7629.8° / 17.8°

Oct

8927.1° / 14.7°

Nov

9123.7° / 10.5°

Dec

7120.3° / 7.5°

Monthly climate evidence for South Whittier — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 32 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	21°C	8°C	55 mm	4	14.9°C	10 h 07	74	Good coverage
February	20.7°C	8.7°C	65 mm	5.3	14.8°C	10 h 55	72	Good coverage
March	22°C	10.6°C	29 mm	3.7	14.8°C	11 h 52	85	Good coverage
April	23.2°C	12°C	17 mm	2.3	15.1°C	12 h 59	92	Good coverage
May	24.5°C	14.6°C	7 mm	1	16.6°C	13 h 54	98	Good coverage
June	26.4°C	16.8°C	1 mm	0.2	18.2°C	14 h 24	89	Good coverage
July	29.4°C	18.8°C	1 mm	0.2	19.7°C	14 h 12	75	Good coverage
August	30.4°C	19°C	0 mm	0.1	20.2°C	13 h 25	72	Good coverage
September	29.8°C	17.8°C	4 mm	0.4	20.0°C	12 h 21	76	Good coverage
October	27.1°C	14.7°C	14 mm	1.7	19.0°C	11 h 16	89	Good coverage
November	23.7°C	10.5°C	19 mm	2.4	17.3°C	10 h 21	91	Good coverage
December	20.3°C	7.5°C	47 mm	4.4	15.6°C	9 h 54	71	Good coverage

Records at FULLERTON MUNI AP, 1998–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	34.4°C31 Jan 2003	-2.1°C14 Jan 2007	70 mm22 Jan 2017	181 mm2017 · driest 0 mm in 2003	28
February	34.4°C27 Feb 2026	1.7°C3 Feb 2011	64 mm21 Feb 2005	250 mm2024 · driest 3 mm in 2002	28
March	37.8°C17 Mar 2026	2.2°C12 Mar 2006	52 mm15 Mar 2003	190 mm2023 · driest 1 mm in 2008	28
April	38.9°C8 Apr 2022	3.9°C10 Apr 1999	30 mm4 Apr 2006	59 mm2020 · driest 0 mm in 2023	29
May	40.0°C15 May 2014	7.8°C1 May 1999	19 mm22 May 2006	32 mm2019 · driest 0 mm in 2007	28
June	42.8°C20 Jun 2016	11.1°C5 Jun 1999	6 mm2 Jun 1999	11 mm1999 · driest 0 mm in 2024	28
July	46.7°C6 Jul 2018	14.4°C24 Jul 1999	6 mm19 Jul 2015	12 mm2015 · driest 0 mm in 2013	29
August	41.7°C18 Aug 2020	13.3°C12 Aug 2010	51 mm20 Aug 2023	56 mm2023 · driest 0 mm in 2004	28
September	45.0°C6 Sep 2024	12.2°C30 Sep 2019	33 mm15 Sep 2015	33 mm2015 · driest 0 mm in 2008	28
October	41.7°C23 Oct 2017	7.2°C29 Oct 2009	49 mm20 Oct 2004	116 mm2004 · driest 0 mm in 2019	28
November	37.2°C3 Nov 2010	1.1°C30 Nov 2021	55 mm15 Nov 2025	137 mm2025 · driest 0 mm in 2021	28
December	30.6°C9 Dec 2017	-0.6°C24 Dec 1998	50 mm24 Dec 2025	234 mm2010 · driest 0 mm in 2024	28

Typical days per month at FULLERTON MUNI AP, 1991–2020
Month	Days 25°C+	Days 30°C+	Heavy rain (10 mm+)
January	7	1	2
February	6	2	2
March	7	2	1
April	10	3	<1
May	12	3	<1
June	20	4	0
July	29	13	0
August	30	16	0
September	26	13	<1
October	20	9	<1
November	11	3	<1
December	5	<1	2

How often, not how much — every day in FULLERTON 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%	13%	7%	13%	19.0–23.6°C
February	50%	19%	7%	23%	18.7–23.5°C
March	63%	13%	4%	10%	19.1–24.3°C
April	78%	7%	1%	2%	20.8–25.5°C
May	92%	3%	<1%	1%	22.1–27.0°C
June	99%	<1%	0%	<1%	24.3–28.5°C
July	99%	<1%	0%	0%	27.6–30.8°C
August	100%	<1%	<1%	0%	28.4–32.1°C
September	99%	1%	<1%	<1%	27.5–32.4°C
October	93%	5%	1%	2%	23.9–30.1°C
November	80%	8%	2%	5%	21.3–25.5°C
December	49%	14%	5%	13%	18.7–22.1°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.

1999Each stripe is one year’s mean temperature against the 27-year average. Warmest: 2014. Coolest: 1999.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 5397841
NOAA station: USW00003166 · FULLERTON MUNI AP
Station distance: 10 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 22 usable years
Daylight: Calculated from latitude 33.95°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 32 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 FULLERTON MUNI AP is what differs

Fullerton→Norwalk→Westminster→Whittier→Buena Park→La Habra→

Or put two places side by side: South Whittier vs Fullerton

Best time to visitSouth Whittier.

May

July

March

The whole year,without the guesswork.

Nearby, measured,and named.

Best time to visit
South Whittier.

The whole year,
without the guesswork.

Nearby, measured,
and named.