Weather in Koshima

14-day forecast · updated today, Thursday, October 29, at 2:42 pm (GMT+9)

Now · partly cloudy 75 °F

Feels like: 75 °F
Low / high: 61 / 75 °F
Rain: 5%
Wind: 6 mph SSE

↘ 30.17 inHg · falling

Today in Koshima: overcast, 61 °F to 75 °F, with a 5% chance of rain and a light breeze from the south-southeast (6 mph). Tomorrow, light drizzle, 69 °F to 77 °F and a 75% chance of rain. The warmest day of the week is Friday 30, at 77 °F.

Temperatures for the next 14 days

75° 61°
Today
77° 69°
Fri 30
75° 62°
Sat 31
73° 57°
Sun 1
77° 67°
Mon 2
74° 63°
Tue 3
75° 65°
Wed 4
76° 66°
Thu 5
73° 60°
Fri 6
69° 60°
Sat 7
69° 63°
Sun 8
66° 57°
Mon 9
66° 57°
Tue 10
67° 56°
Wed 11

Day by day

Day	Sky	Low / high	Rain	Max wind	Max wave	High tides	Model
Today · 29	Overcast	61 / 75 °F	5%	7 mph SE	4.4 ft	8:22 am · 7:34 pm	ECMWF
Fri 30	Light drizzle	69 / 77 °F	75% · 0.04 in	7 mph W	3.9 ft	9:13 am · 8:15 pm	ECMWF
Sat 31	Mainly clear	62 / 75 °F	10%	6 mph NNW	5.2 ft	10:14 am · 9:04 pm	ECMWF
Sun 1	Overcast	57 / 73 °F	0%	7 mph SSE	8.5 ft	11:31 am · 10:16 pm	ECMWF
Mon 2	Light rain	67 / 77 °F	77% · 0.27 in	13 mph WSW	8.1 ft	1:03 pm	ECMWF
Tue 3	Light drizzle	63 / 74 °F	20% · 0.06 in	5 mph ESE	8.5 ft	12:07 am · 2:17 pm	ECMWF
Wed 4	Overcast	65 / 75 °F	14%	8 mph ENE	9.4 ft	1:58 am · 3:06 pm	ECMWF
Thu 5	Drizzle	66 / 76 °F	55% · 0.14 in	5 mph E	10 ft	3:17 am · 3:43 pm	ECMWF
Fri 6	Partly cloudy	60 / 73 °F	37%	8 mph N	8.5 ft	4:15 am · 4:15 pm	ECMWF
Sat 7	Overcast	60 / 69 °F	18%	6 mph NE	6.0 ft	5:03 am · 4:44 pm	ECMWF
Sun 8	Drizzle	63 / 69 °F	33% · 0.19 in	6 mph NNE	5.4 ft	5:45 am · 5:12 pm	ECMWF
Mon 9	Overcast	57 / 66 °F	43%	6 mph N	6.0 ft	6:23 am · 5:39 pm	ECMWF
Tue 10	Overcast	57 / 66 °F	27%	5 mph NNE	4.8 ft	6:59 am · 6:06 pm	ECMWF
Wed 11	Overcast	56 / 67 °F	30%	5 mph S	4.4 ft	7:34 am · 6:34 pm	ECMWF

Each day comes from the best model covering this spot: regional ones first (HRRR and NBM in the U.S., AROME, ICON-EU), then ECMWF; day 16, NOAA GFS. Waves: Météo-France up to day 10, then ECMWF WAM, coarser and further offshore. High tides: our own tide calculation.

Today, every 3 hours

Time	12:00 am	3:00 am	6:00 am	9:00 am	12:00 pm	3:00 pm	6:00 pm	9:00 pm
Sky	Clear	Partly cloudy	Mainly clear	Partly cloudy	Mainly clear	Partly cloudy	Mainly clear	Overcast
Temperature	62°	62°	61°	71°	74°	75°	70°	71°
Chance of rain	0%	0%	0%	0%	0%	0%	0%	0%
Rain	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in	0.00 in
Wind (mph)	4 NE	5 NE	4 NE	7 SE	6 SE	6 SSE	5 SSE	5 SSE
Humidity	88%	88%	92%	68%	59%	57%	74%	76%
UV	0	0	0	2	5	1	0	0
Model	ECMWF	ECMWF	ECMWF	ECMWF	ECMWF	ECMWF	ECMWF	ECMWF

Do the models agree?

Low confidence

They don't agree on rain tomorrow: it may change, so check again closer to the day.

What 4 forecast models say for the next few days. The closer they are, the more reliable the forecast.

HighRainWind

Do the models agree? · High
High (°F)	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	75°	77°	75°	73°	77°	74°	75°
AIFS	81°	81°	78°	80°	81°	77°	80°
GFS	74°	79°	78°	75°	78°	76°	73°
ICON	75°	75°	72°	75°	78°	72°	74°
Confidence	medium	medium	medium	medium	high	medium	medium

Do the models agree? · Rain
Rain	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	0	0.04 in	0	0	0.27 in	0.06 in	0
AIFS	0.01 in	0.30 in	0	0	0.12 in	0	0.03 in
GFS	0.02 in	0.03 in	0	0	0.09 in	0	0
ICON	0	0.11 in	0.01 in	0	0	0	0
Confidence	high	low	high	high	medium	medium	high

Do the models agree? · Wind
Wind (mph)	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF	717	724	620	718	1333	521	822
AIFS	13	16	18	14	21	21	23
GFS	710	714	915	712	1120	914	1014
ICON	618	839	1040	520	1038	1026	1230
Confidence	high	medium	medium	medium	medium	low	low

Chance of rain from the ensemble models

Model	Today	Fri 30	Sat 31	Sun 1	Mon 2	Tue 3	Wed 4
ECMWF (51 scenarios)	5%	75%	10%	0%	77%	20%	14%
GFS (GEFS, 31 scenarios)	0%	52%	3%	0%	55%	3%	12%

Each model's day runs midnight to midnight local time; models that reach fewer days are left blank. Rain: daily total. Wind: the day's highest average wind and, in small type, the strongest gust. Highlighted: values that stand out from the rest. The chance of rain comes from many runs of the same model with slightly different starting data.

Outlook

How the coming weeks and months compare with what is normal for the time of year. It is a trend, not a day-by-day forecast.

Next few weeks, compared with normal: normal temperatures, normal rain and a slightly warmer sea.

Next 6 weeks

When	TemperatureTemp.	Rain	Sea	Typical high / low
Nov 2 – Nov 8Nov 2–Nov 8	Normal +0.5 °F	A bit below −47%	A bit above +1.4 °F	—
Nov 9 – Nov 15Nov 9–Nov 15	Normal +0.4 °F	Normal	A bit above +1.3 °F	—
Nov 16 – Nov 22Nov 16–Nov 22	A bit above +0.9 °F	Normal	A bit above +0.9 °F	70° / 68°
Nov 23 – Nov 29Nov 23–Nov 29	A bit above +1.6 °F	A bit above +21%	A bit above +0.7 °F	69° / 67°
Nov 30 – Dec 6Nov 30–Dec 6	A bit above +1.8 °F	Normal	A bit above +0.5 °F	67° / 65°

Coming months

When	TemperatureTemp.	Rain	Sea
November	A bit above +1.6 °F	A bit above +24%	A bit above +1.3 °F
December	A bit above +1.6 °F	Above +50%	A bit above +1.3 °F
January	A bit above +1.8 °F	A bit above +28%	A bit above +1.3 °F
February	A bit above +2.5 °F	A bit above +32%	A bit above +1.4 °F
March	A bit above +1.8 °F	A bit above +29%	A bit above +1.3 °F

Weeks: ECMWF 46-day (average of its scenarios), against the normal of the last 20 years for those dates. Months: ECMWF SEAS5. Rain: total against normal. The further ahead, the closer it gets to normal and the less detail it can give.

Koshima climate by monthClimate by month

Normal weather for each month (1991–2020 averages)

The best time to visit Koshima is from June to October: highs of 69 °F to 79 °F, about 17 rainy days a month and 5 hours of sunshine a day.

Typhoon season: from July to October, peaking in September. In the last 30 years (1996–2025), 44 tropical cyclones passed within 93 mi of Koshima, one or two a year; 26 of them with hurricane-force winds (74 mph or more). The most recent: Peipah, in September 2025.

49° 39°

JanJ
50° 40°

FebF
55° 44°

MarM
62° 51°

AprA
68° 57°

MayM
73° 63°

JunJ
79° 69°

JulJ
79° 69°

AugA
76° 66°

SepS
69° 59°

OctO
61° 51°

NovN
53° 42°

DecD

Highs and lows
Monthly rainfall
Best time

Month	High	Low	Rain	Rainy daysDays	Sun (h/day)	Water	Waves	Cyclones
JanuaryJan	49°	39°	5.86 in	12	3.9	69°	5.1 ft	–
FebruaryFeb	50°	40°	6.99 in	12	4.6	68°	5.0 ft	–
MarchMar	55°	44°	8.77 in	15	5.4	69°	4.6 ft	–
AprilApr	62°	51°	10.10 in	13	5.7	71°	4.0 ft	–
MayMay	68°	57°	13.02 in	13	5.6	74°	3.4 ft	3
JuneJun	73°	63°	24.70 in	21	3.7	77°	3.5 ft	4
JulyJul	79°	69°	16.02 in	17	6.3	82°	3.7 ft	8
AugustAug	79°	69°	10.16 in	17	7.1	84°	4.1 ft	9
SeptemberSep	76°	66°	11.73 in	15	5.7	82°	4.2 ft	14
OctoberOct	69°	59°	7.86 in	12	5.2	79°	4.7 ft	6
NovemberNov	61°	51°	7.89 in	11	4.5	76°	4.1 ft	–
DecemberDec	53°	42°	6.04 in	11	3.8	72°	5.1 ft	–

Month	Water	Waves	Cyclones
Jan	69°	5.1 ft	–
Feb	68°	5.0 ft	–
Mar	69°	4.6 ft	–
Apr	71°	4.0 ft	–
May	74°	3.4 ft	3
Jun	77°	3.5 ft	4
Jul	82°	3.7 ft	8
Aug	84°	4.1 ft	9
Sep	82°	4.2 ft	14
Oct	79°	4.7 ft	6
Nov	76°	4.1 ft	–
Dec	72°	5.1 ft	–

Days: rainy days in the month. Sun: hours a day.

A normal year brings 129.13 in of rain on about 167 days and about 1,850 hours of sunshine.

Cyclones: how many tropical cyclones (tropical storms, hurricanes and typhoons) passed within 93 mi in each month from 1996 to 2025, according to IBTrACS (NOAA).

1991–2020 averages. Highs, lows and rainfall: TerraClimate; rainy days (0.04 in or more): NASA POWER (MERRA-2); sunshine hours: estimated from solar radiation; water: NOAA OISST; waves (average height): ERA5, 2011–2020. Normals are not a forecast: any given year can turn out very different. Sources and licenses

Temperature

Now75 °Ffeels like 75 °F

Tomorrow69 / 77 °F

It's 75 °F now (feels like 75 °F). Today, 61 °F to 75 °F; tomorrow, 69 °F to 77 °F.

Chance of rain

Today 5%
Fri 30 75% 0.04 in
Sat 31 10%
Sun 1 0%
Mon 2 77% 0.27 in
Tue 3 20% 0.06 in
Wed 4 14%

Today the chance of rain reaches 5%. The next day with likely rain is Friday 30: 75% and 0.04 in.

Recent rain: last 24 hours, 0.00 in; last 3 days, 0.26 in; last 7 days, 3.20 in.

Humidity and dew point

Humidity57%

Dew point59 °F

Humidity is 57% now and the dew point is 59 °F.

The dew point is the temperature at which the air becomes saturated: the higher it is, the heavier the air feels.

Visibility and fog

Now15 migood

Clouds69%

Visibility is good now (15 mi). No fog expected today.

The model gives visibility up to about 15 mi: beyond that, the horizon is clear.

UV index

Now2

Today's peak5moderate

Fri 30: 5 · Sat 31: 6 · Sun 1: 6

Index	Level	What to do
0–2	low	No special protection needed.
3–5	moderate	Hat, sunglasses and sunscreen around midday.
6–7	high	Sunscreen, hat and shade between 12 and 4 pm.
8–10	very high	Avoid the midday sun; reflection off the water adds to it.
11+	extreme	Avoid the sun between 11 am and 5 pm; protect yourself even if it is cloudy.

Reflection off water and sand adds radiation: protect yourself more on a boat or at the beach.

Barometric pressure

↗ Rising Anglers say fish bite less for a while
→ Steady Anglers expect normal activity
↘ Falling · now Anglers say fish feed more before the change

30.0030.1030.2030.30 30.04

Falling now (−0.05 inHg in 3 hours). Over the next 48 hours: −0.03 inHg. Falling pressure: anglers say fish feed more before the change. Fast changes, either way, tend to affect fishing.

Air and pollen

Air qualityModerate · 43

Saharan dustNo

Previous days

The weather over the last 30 days, as the models analyzed it. Tap a day to see it hour by hour.

Day	Sky	Low / high	Rain	Max wind
Wed 28	Partly cloudy	63 / 74 °F	0	8 mph NNE
Tue 27	Light drizzle	69 / 78 °F	0.16 in	12 mph NNW
Mon 26	Light rain	74 / 83 °F	0.70 in	12 mph WSW
Sun 25	Light rain	77 / 82 °F	1.08 in	12 mph SSE
Sat 24	Heavy drizzle	76 / 82 °F	0.35 in	15 mph SE
Fri 23	Light rain	73 / 78 °F	0.88 in	15 mph E
Thu 22	Drizzle	69 / 79 °F	0.09 in	9 mph NE

Show all 30 days

Day	Sky	Low / high	Rain	Max wind
Wed 21	Light drizzle	72 / 85 °F	0.02 in	10 mph NW
Tue 20	Overcast	74 / 83 °F	0	6 mph S
Mon 19	Light drizzle	75 / 84 °F	0.04 in	6 mph SE
Sun 18	Light drizzle	70 / 81 °F	0.03 in	11 mph E
Sat 17	Mainly clear	68 / 80 °F	0	9 mph ENE
Fri 16	Overcast	64 / 80 °F	0	8 mph ENE
Thu 15	Drizzle	65 / 76 °F	0.09 in	7 mph ENE
Wed 14	Light drizzle	65 / 79 °F	0.04 in	9 mph NNW
Tue 13	Light drizzle	72 / 81 °F	0.06 in	8 mph SSE
Mon 12	Partly cloudy	71 / 81 °F	0	8 mph E
Sun 11	Drizzle	73 / 81 °F	0.11 in	10 mph E
Sat 10	Rain	73 / 77 °F	2.10 in	12 mph E
Fri 9	Light rain	67 / 82 °F	0.35 in	10 mph ENE
Thu 8	Drizzle	66 / 77 °F	0.14 in	5 mph NE
Wed 7	Mainly clear	67 / 78 °F	0	7 mph N
Tue 6	Light drizzle	70 / 77 °F	0.02 in	13 mph NNW
Mon 5	Partly cloudy	72 / 82 °F	0	9 mph N
Sun 4	Drizzle	69 / 83 °F	0.11 in	5 mph N
Sat 3	Light drizzle	72 / 82 °F	0.11 in	10 mph ENE
Fri 2	Heavy drizzle	73 / 84 °F	0.26 in	5 mph ESE
Thu 1	Light drizzle	74 / 85 °F	0.04 in	6 mph NNW
Wed 30	Heavy drizzle	75 / 85 °F	0.11 in	4 mph SSW
Tue 29	Heavy drizzle	77 / 85 °F	0.25 in	7 mph W

These are the models at the start of each day (ECMWF and GFS; waves from Météo-France), not readings from a weather station: there can be differences at specific spots.

Questions about the weather in KoshimaQuestions

What's the weather like today in Koshima?

Overcast, from 61 °F to 75 °F, with a light breeze from the south-southeast (6 mph) and a 5% chance of rain.

Will it rain tomorrow in Koshima?

On Friday 30 the chance of rain is 75% (0.04 in): light drizzle.

How warm will it be this week?

Between a low of 57 °F and a high of 77 °F; the warmest day, Friday 30.

What's the UV index today?

It reaches 5 (moderate). Hat, sunglasses and sunscreen around midday.

Is the pressure rising or falling?

It's 30.17 inHg and falling: +0.04 inHg over the last 24 hours.

When is the best time to visit Koshima?

The best time to visit Koshima is from June to October: highs of 69 °F to 79 °F, about 17 rainy days a month and 5 hours of sunshine a day.

What is the weather like in Koshima in October?

In October, Koshima normally sees highs of 69 °F and lows of 59 °F, with about 12 rainy days (7.86 in for the month) and 5 hours of sunshine a day. The sea is around 79 °F. These are 1991–2020 averages.

What are the warmest and wettest months in Koshima?

The warmest is July, with average highs of 79 °F, and the coldest January, with lows of 39 °F. The wettest is June (24.70 in) and the driest, January.

When is typhoon season in Koshima?

Typhoon season: from July to October, peaking in September. In the last 30 years (1996–2025), 44 tropical cyclones passed within 93 mi of Koshima, one or two a year; 26 of them with hurricane-force winds (74 mph or more). The most recent: Peipah, in September 2025.

More about Koshima today

Weather near Koshima

Only places with a different forecast: spots a few miles apart share the same model cell and wouldn't add anything.

Learn more

Weather: Open-Meteo, CC BY 4.0, with the best model for each spot and lead time (NOAA HRRR and NBM in the U.S., Météo-France AROME, DWD ICON-EU, ECMWF IFS and NOAA GFS); ECMWF grid point 2.4 mi away. The comparison also uses ICON (DWD), AIFS (ECMWF) and ARPEGE (Météo-France). Outlook: ECMWF 46-day and SEAS5. Chance of rain from ensemble models (ECMWF, GEFS and NBM). UV, air quality and pollen: CAMS (Copernicus).

Forecast from Open-Meteo (CC BY 4.0) with models from ECMWF, NOAA, Météo-France, DWD, Copernicus Marine and CAMS. Updated at 2:42 pm (local time).

Spotted a mistake? Tell us · Where the weather and sea data come from