United States · 1991–2020

Best time to visit
Caldwell.

April leads for comfortable weather in Caldwell: typically 26.3°C by day, 12.3°C at night, with 87 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortApril

Typical high26.3°C

Typical low12.3°C

Rain in April87 mm

Comfort

April

April · March · November

78climate match

Beach

July

July · June · September

72climate match

Outdoors

March

March · February · November

78climate match

The weakest month is August, scoring 38 against April’s 78 — days average 36.5°C, 13° 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

4416.9° / 2°

Feb

5518.6° / 4.3°

Mar

7522.6° / 8.4°

Apr

7826.3° / 12.3°

May

5930.4° / 17.3°

Jun

4334.1° / 21°

Jul

4435.9° / 22.3°

Aug

3836.5° / 22.1°

Sep

5233.5° / 18.7°

Oct

6828.6° / 13°

Nov

7022.3° / 7.6°

Dec

4918° / 3.4°

Monthly climate evidence for Caldwell — daylight is calculated from latitude, everything else is measured
Month	Day	Night	Rain	Wet days	Daylight	Comfort	Coverage
January	16.9°C	2°C	78 mm	6.9	10 h 22	44	Strong coverage
February	18.6°C	4.3°C	71 mm	6.7	11 h 04	55	Strong coverage
March	22.6°C	8.4°C	80 mm	6.1	11 h 54	75	Strong coverage
April	26.3°C	12.3°C	87 mm	5.3	12 h 52	78	Strong coverage
May	30.4°C	17.3°C	124 mm	6.7	13 h 41	59	Strong coverage
June	34.1°C	21°C	103 mm	6.5	14 h 06	43	Strong coverage
July	35.9°C	22.3°C	48 mm	4.7	13 h 56	44	Strong coverage
August	36.5°C	22.1°C	81 mm	4.9	13 h 15	38	Strong coverage
September	33.5°C	18.7°C	89 mm	5.8	12 h 19	52	Strong coverage
October	28.6°C	13°C	113 mm	5.7	11 h 23	68	Strong coverage
November	22.3°C	7.6°C	97 mm	6.2	10 h 34	70	Strong coverage
December	18°C	3.4°C	88 mm	6.8	10 h 11	49	Strong coverage

What has changed

Caldwell runs +2.2°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

+2.8

Feb

+2.5

Mar

+2.4

Apr

+1.5

May

+2.1

Jun

+2.3

Jul

+1.5

Aug

+2.1

Sep

+2.6

Oct

+2.5

Nov

+1.7

Dec

+2.1

April daytime highs, 2012–2025. Last recorded: 28.7°C.

Records at SOMERVILLE DAM, 1963–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	31.7°C3 Jan 2000	-13.9°C9 Jan 2010	64 mm20 Jan 1989	285 mm1991 · driest 1 mm in 2018	61
February	35.6°C22 Feb 1996	-11.7°C5 Feb 2011	96 mm21 Feb 2003	221 mm1992 · driest 0 mm in 2026	58
March	32.8°C23 Mar 1971	-8.9°C3 Mar 2002	113 mm29 Mar 2018	180 mm2007 · driest 2 mm in 2011	61
April	35.6°C18 Apr 2006	-1.7°C7 Apr 2009	169 mm13 Apr 1969	249 mm1969 · driest 0 mm in 2022	58
May	43.3°C30 May 1996	-0.6°C4 May 2011	300 mm27 May 2016	499 mm2016 · driest 12 mm in 1996	60
June	42.8°C26 Jun 2009	11.1°C1 Jun 1988	125 mm24 Jun 1968	413 mm1968 · driest 0 mm in 1967	61
July	42.2°C11 Jul 2022	12.8°C25 Jul 2019	88 mm9 Jul 1968	207 mm2024 · driest 0 mm in 2000	62
August	42.8°C28 Aug 2011	13.3°C15 Aug 1989	150 mm27 Aug 2017	423 mm2017 · driest 0 mm in 2023	61
September	45.6°C5 Sep 2000	5.6°C27 Sep 2000	127 mm13 Sep 1974	269 mm1968 · driest 3 mm in 2005	58
October	37.2°C5 Oct 2019	-3.9°C31 Oct 2019	387 mm17 Oct 1994	481 mm1994 · driest 0 mm in 2024	60
November	32.8°C4 Nov 2016	-8.9°C27 Nov 2010	128 mm17 Nov 2015	237 mm2004 · driest 3 mm in 1966	61
December	29.4°C5 Dec 1993	-16.1°C23 Dec 1989	127 mm13 Dec 2015	217 mm2015 · driest 1 mm in 2023	62

Typical days per month at SOMERVILLE DAM, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	2	0	12	2
February	4	<1	6	2
March	12	1	3	3
April	21	5	<1	3
May	28	19	0	3
June	29	27	0	3
July	31	30	0	2
August	31	30	0	2
September	29	26	0	3
October	24	14	<1	3
November	11	2	3	3
December	3	0	10	2

The best month has moved. On the 1961–1990 numbers the strongest month here was April (scoring 87); on 2011–2025 it is March (85). Both are scored the same way, from the same station — only the climate underneath changed.

How often, not how much — every day in SOMERVILLE DAM’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	27%	23%	8%	25%	12.4–19.3°C
February	38%	23%	7%	22%	14.8–21.5°C
March	60%	21%	8%	18%	20.2–25.2°C
April	78%	17%	8%	16%	24.0–27.9°C
May	77%	22%	11%	23%	27.7–31.9°C
June	79%	21%	9%	22%	31.2–36.2°C
July	84%	16%	5%	15%	33.1–37.4°C
August	85%	15%	7%	13%	33.4–38.0°C
September	80%	20%	9%	17%	30.3–34.5°C
October	79%	19%	9%	21%	26.0–30.4°C
November	56%	20%	9%	20%	19.2–25.5°C
December	33%	22%	7%	24%	14.9–20.3°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.

1966Each stripe is one year’s mean temperature against the 51-year average. Warmest: 2024. Coolest: 2010.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 4678111
NOAA station: USC00418446 · SOMERVILLE DAM
Station distance: 26.1 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 27 usable years
Daylight: Calculated from latitude 30.53°, 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 SOMERVILLE DAM is what differs

Somerville→Burton→Carmine→Big Creek→Birch→Center Line→

Or put two places side by side: Caldwell vs Somerville

Best time to visitCaldwell.

April

July

March

The whole year,without the guesswork.

Caldwell runs +2.2°Con the 1961–1990 baseline.

Nearby, measured,and named.

Best time to visit
Caldwell.

The whole year,
without the guesswork.

Caldwell runs +2.2°C
on the 1961–1990 baseline.

Nearby, measured,
and named.