Japan · 1991–2020

Best time to visit
Koga.

October leads for comfortable weather in Koga: typically 23.6°C by day, 15.6°C at night, with 125 mm of rain. Based on measured 1991–2020 NOAA station history.

Best comfortOctober

Typical high23.6°C

Typical low15.6°C

Rain in October125 mm

Comfort

October

October · May · April

81climate match

Beach

September

September · October · May

61climate match

Outdoors

November

November · April · October

78climate match

The weakest month is July, scoring 5 against October’s 81 — 360 mm of rain falls.

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

1810.2° / 3.5°

Feb

2911.6° / 3.9°

Mar

3515° / 6.5°

Apr

6019.8° / 11.2°

May

7624.3° / 15.7°

Jun

3727.1° / 19.9°

Jul

531.2° / 24.4°

Aug

1732.5° / 25.2°

Sep

4428.5° / 21.3°

Oct

8123.6° / 15.6°

Nov

5918.1° / 10.1°

Dec

3112.8° / 5.2°

Monthly climate evidence for Koga — daylight is calculated from latitude, everything else is measured, sea temperature from the nearest open water 18 km away
Month	Day	Night	Rain	Wet days	Sea	Daylight	Comfort	Coverage
January	10.2°C	3.5°C	98 mm	11.2	15.6°C	10 h 08	18	Good coverage
February	11.6°C	3.9°C	70 mm	9	14.1°C	10 h 55	29	Good coverage
March	15°C	6.5°C	126 mm	11.5	14.1°C	11 h 52	35	Good coverage
April	19.8°C	11.2°C	126 mm	9.8	15.4°C	12 h 59	60	Good coverage
May	24.3°C	15.7°C	149 mm	9.7	17.9°C	13 h 53	76	Good coverage
June	27.1°C	19.9°C	289 mm	12.6	20.9°C	14 h 23	37	Good coverage
July	31.2°C	24.4°C	360 mm	13.7	24.6°C	14 h 11	5	Good coverage
August	32.5°C	25.2°C	241 mm	11.7	26.9°C	13 h 24	17	Good coverage
September	28.5°C	21.3°C	192 mm	11	25.5°C	12 h 20	44	Good coverage
October	23.6°C	15.6°C	125 mm	7.5	22.8°C	11 h 17	81	Good coverage
November	18.1°C	10.1°C	91 mm	8.2	20.4°C	10 h 22	59	Good coverage
December	12.8°C	5.2°C	88 mm	11	17.9°C	9 h 55	31	Good coverage

Records at FUKUOKA, 1951–2026
Month	Record high	Record low	Wettest day	Wettest / driest month	Years
January	20.4°C29 Jan 1957	-4.6°C5 Jan 1970	48 mm26 Jan 2002	193 mm1972 · driest 0 mm in 2026	75
February	23.8°C21 Feb 2004	-5.2°C16 Feb 1977	61 mm15 Feb 1968	175 mm1951 · driest 0 mm in 2026	75
March	26.9°C25 Mar 2025	-3.7°C2 Mar 1994	102 mm25 Mar 1958	218 mm1958 · driest 0 mm in 2026	75
April	29.9°C22 Apr 2004	0.1°C6 Apr 1965	216 mm15 Apr 1955	361 mm1955 · driest 0 mm in 2025	75
May	32.3°C22 May 1998	4.8°C1 May 1965	138 mm14 May 1995	496 mm1963 · driest 0 mm in 2025	75
June	37.3°C20 Jun 2004	10.8°C3 Jun 1959	308 mm25 Jun 1953	1056 mm1953 · driest 0 mm in 2025	75
July	38.3°C20 Jul 2018	13.8°C4 Jul 1966	253 mm25 Jul 2009	886 mm1980 · driest 0 mm in 2025	75
August	38.1°C21 Aug 2018	15.4°C26 Aug 1956	230 mm14 Aug 2021	881 mm2021 · driest 0 mm in 2025	74
September	36.5°C1 Sep 1990	9.8°C29 Sep 1965	217 mm25 Sep 1954	603 mm2016 · driest 0 mm in 2025	74
October	31.9°C11 Oct 1999	4.8°C23 Oct 1955	172 mm14 Oct 1951	290 mm2017 · driest 0 mm in 2025	74
November	27.5°C8 Nov 2015	-0.6°C21 Nov 1953	186 mm2 Nov 2024	355 mm2024 · driest 0 mm in 2025	74
December	26.0°C4 Dec 2018	-3.1°C13 Dec 1964	87 mm5 Dec 2004	143 mm2016 · driest 0 mm in 2025	74

Typical days per month at FUKUOKA, 1991–2020
Month	Days 25°C+	Days 30°C+	Frost nights	Heavy rain (10 mm+)
January	0	0	1	2
February	0	0	<1	2
March	0	0	0	4
April	2	0	0	4
May	13	<1	0	4
June	22	4	0	5
July	28	20	0	6
August	29	24	0	5
September	26	9	0	4
October	9	<1	0	3
November	<1	0	0	3
December	0	0	<1	2

How often, not how much — every day in FUKUOKA’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%	33%	8%	39%	8.3–11.4°C
February	1%	35%	9%	44%	8.5–13.2°C
March	5%	36%	13%	43%	12.8–15.8°C
April	29%	36%	16%	42%	18.2–21.0°C
May	60%	34%	16%	37%	22.6–25.2°C
June	58%	42%	22%	55%	25.2–27.9°C
July	62%	39%	21%	44%	28.7–32.8°C
August	67%	34%	18%	42%	30.3–33.8°C
September	62%	38%	18%	44%	26.4–29.7°C
October	66%	26%	10%	25%	21.9–24.6°C
November	20%	30%	10%	32%	16.4–19.5°C
December	<1%	32%	7%	35%	10.7–14.0°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.

1951Each stripe is one year’s mean temperature against the 41-year average. Warmest: 2025. Coolest: 1965.2025

The evidence behind this page

Nearby, measured,
and named.

Place identity: GeoNames 1859094
NOAA station: JA000047807 · FUKUOKA
Station distance: 18.4 km from the place centre
Climate period: 1991–2020
Minimum month coverage: 15 usable years
Daylight: Calculated from latitude 33.73°, mid-month, sunrise to sunset including refraction. Not a station measurement.
Sea temperature: NOAA OISST v2.1 1991–2020 monthly climatology, nearest open water 18 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 FUKUOKA is what differs

Fukuoka→Iizuka→Kasuga→Chikushino-shi→Ōnojō→Itoshima→

Or put two places side by side: Koga vs Fukuoka

Best time to visitKoga.