Current Conditions

Isumi, Chiba

76°F24°C

Showers

Wind

E 11 mph17 km/h

Humidity

76%

Cloud Cover

86%

As of Wednesday, September 23, 2026 at 4:15 PM GMT+9

Today's Outlook

Day

Partly cloudy and warm, with a high of 79°F26°C and morning low of 74°F23°C. Light wind from the WNW around 5 mph7 km/h. 67% chance of showers throughout the day. Heavy, humid air.

Night

Mostly cloudy, with a low around 74°F23°C. Breezy from the ESE at 6 to 8 mph9 to 13 km/h. 82% chance of showers overnight.

7-Day Forecast

Condition	High (°F)	Low (°F)	Precip (mm)	Cloud Cover (%)	Wind (mph)
Showers	High 79°F26°C	Low 74°F23°C	Precip 0.09 in2.3 mm82%	Cloud 52%	Wind ESE 5 mph8 km/h	Thursday: Partly cloudy and warm, with a high of 79°F26°C and morning low of 74°F23°C. Light wind from the WNW around 5 mph7 km/h. 67% chance of showers throughout the day. Heavy, humid air. Thursday Night: Mostly cloudy, with a low around 74°F23°C. Breezy from the ESE at 6 to 8 mph9 to 13 km/h. 82% chance of showers overnight.
Drizzle	High 76°F24°C	Low 73°F23°C	Precip 0.02 in0.4 mm14%	Cloud 67%	Wind NE 9 mph15 km/h	Friday: Mostly cloudy and warm, with a high of 76°F24°C. Breezy from the NE at 10 to 11 mph16 to 17 km/h. Humid. Friday Night: Mostly cloudy, with a low around 74°F23°C. Breezy from the NE at 8 to 9 mph13 to 15 km/h. 14% chance of drizzle in the evening.
Rain	High 73°F23°C	Low 70°F21°C	Precip 0.98 in24.9 mm97%	Cloud 99%	Wind NE 10 mph16 km/h	Saturday: Overcast and warm, with a high of 71°F22°C. Breezy from the NE at 11 mph17 km/h. 97% chance of rain throughout the day. Humid. Saturday Night: Overcast, with a low around 70°F21°C. Breezy from the NNE at 9 to 11 mph14 to 17 km/h. 93% chance of rain throughout the night.
Rain	High 73°F23°C	Low 70°F21°C	Precip 0.67 in16.9 mm69%	Cloud 98%	Wind NNE 8 mph14 km/h	Sunday: Overcast and warm, with a high of 73°F23°C. Breezy from the NNE at 8 to 10 mph13 to 16 km/h. 69% chance of rain throughout the day. Humid. Sunday Night: Overcast, with a low around 70°F21°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 69% chance of rain throughout the night.
Light Rain	High 77°F25°C	Low 73°F23°C	Precip 0.5 in12.7 mm58%	Cloud 94%	Wind SW 10 mph16 km/h	Monday: Overcast and warm, with a high of 77°F25°C. Breezy from the SW at 11 to 12 mph17 to 20 km/h. 44% chance of light rain throughout the day. Heavy, humid air. Monday Night: Overcast, with a low around 73°F23°C. Breezy from the WSW at 9 to 11 mph14 to 17 km/h. 58% chance of light rain throughout the night.
Light Rain	High 75°F24°C	Low 73°F23°C	Precip 0.43 in11 mm45%	Cloud 87%	Wind SW 8 mph13 km/h	Tuesday: Overcast and warm, with a high of 75°F24°C. Breezy from the SW at 8 mph13 km/h. 45% chance of light rain throughout the day. Humid. Tuesday Night: Overcast, with a low around 74°F23°C. Breezy from the SW at 8 to 9 mph14 to 15 km/h. 42% chance of light rain throughout the night.
Showers	High 77°F25°C	Low 74°F23°C	Precip 0.39 in10 mm45%	Cloud 65%	Wind SW 12 mph20 km/h	Wednesday: Mostly cloudy and warm, with a high of 77°F25°C. Breezy from the SW at 13 to 14 mph21 to 23 km/h. 39% chance of showers throughout the day. Heavy, humid air. Wednesday Night: Mostly cloudy, with a low around 74°F23°C. Breezy from the SW at 12 to 14 mph19 to 22 km/h. 45% chance of showers throughout the night.

15-Day Forecast

	Day	High	Low	Precip	Cloud Cover	Condition	Wind
	ThursdaySep 24	79°F26°C	74°F23°C	0.09 in2.3 mm· 82%	52%	Showers	ESE 5 mph8 km/h
DayPartly cloudy and warm, with a high of 79°F26°C and morning low of 74°F23°C. Light wind from the WNW around 5 mph7 km/h. 67% chance of showers throughout the day. Heavy, humid air. NightMostly cloudy, with a low around 74°F23°C. Breezy from the ESE at 6 to 8 mph9 to 13 km/h. 82% chance of showers overnight.
	FridaySep 25	76°F24°C	73°F23°C	0.02 in0.4 mm· 14%	67%	Drizzle	NE 9 mph15 km/h
DayMostly cloudy and warm, with a high of 76°F24°C. Breezy from the NE at 10 to 11 mph16 to 17 km/h. Humid. NightMostly cloudy, with a low around 74°F23°C. Breezy from the NE at 8 to 9 mph13 to 15 km/h. 14% chance of drizzle in the evening.
	SaturdaySep 26	73°F23°C	70°F21°C	0.98 in24.9 mm· 97%	99%	Rain	NE 10 mph16 km/h
DayOvercast and warm, with a high of 71°F22°C. Breezy from the NE at 11 mph17 km/h. 97% chance of rain throughout the day. Humid. NightOvercast, with a low around 70°F21°C. Breezy from the NNE at 9 to 11 mph14 to 17 km/h. 93% chance of rain throughout the night.
	SundaySep 27	73°F23°C	70°F21°C	0.67 in16.9 mm· 69%	98%	Rain	NNE 8 mph14 km/h
DayOvercast and warm, with a high of 73°F23°C. Breezy from the NNE at 8 to 10 mph13 to 16 km/h. 69% chance of rain throughout the day. Humid. NightOvercast, with a low around 70°F21°C. Breezy from the NNE at 9 to 10 mph14 to 17 km/h. 69% chance of rain throughout the night.
	MondaySep 28	77°F25°C	73°F23°C	0.5 in12.7 mm· 58%	94%	Light Rain	SW 10 mph16 km/h
DayOvercast and warm, with a high of 77°F25°C. Breezy from the SW at 11 to 12 mph17 to 20 km/h. 44% chance of light rain throughout the day. Heavy, humid air. NightOvercast, with a low around 73°F23°C. Breezy from the WSW at 9 to 11 mph14 to 17 km/h. 58% chance of light rain throughout the night.
	TuesdaySep 29	75°F24°C	73°F23°C	0.43 in11 mm· 45%	87%	Light Rain	SW 8 mph13 km/h
DayOvercast and warm, with a high of 75°F24°C. Breezy from the SW at 8 mph13 km/h. 45% chance of light rain throughout the day. Humid. NightOvercast, with a low around 74°F23°C. Breezy from the SW at 8 to 9 mph14 to 15 km/h. 42% chance of light rain throughout the night.
	WednesdaySep 30	77°F25°C	74°F23°C	0.39 in10 mm· 45%	65%	Showers	SW 12 mph20 km/h
DayMostly cloudy and warm, with a high of 77°F25°C. Breezy from the SW at 13 to 14 mph21 to 23 km/h. 39% chance of showers throughout the day. Heavy, humid air. NightMostly cloudy, with a low around 74°F23°C. Breezy from the SW at 12 to 14 mph19 to 22 km/h. 45% chance of showers throughout the night.
	ThursdayOct 1	75°F24°C	72°F22°C	0.46 in11.6 mm· 42%	60%	Showers	SW 12 mph20 km/h
DayMostly cloudy and warm, with a high of 75°F24°C. Breezy from the NNW at 12 mph19 km/h. 42% chance of showers throughout the day. Humid. NightMostly cloudy, with a low around 72°F22°C. Breezy from the SW at 13 to 14 mph20 to 23 km/h. 35% chance of showers throughout the night.
	FridayOct 2	71°F22°C	68°F20°C	0.22 in5.6 mm· 36%	63%	Showers	NE 14 mph22 km/h
DayMostly cloudy and warm, with a high of 71°F21°C. Windy from the NE at 15 to 16 mph24 to 26 km/h. 34% chance of showers throughout the day. NightMostly cloudy, with a low around 69°F21°C. Breezy from the NE at 13 to 14 mph21 to 23 km/h. 36% chance of showers throughout the night.
	SaturdayOct 3	72°F22°C	68°F20°C	0.22 in5.7 mm· 23%	61%	Showers	NE 12 mph19 km/h
DayMostly cloudy and warm, with a high of 72°F22°C. Breezy from the NE at 12 mph19 km/h. 22% chance of showers throughout the day. NightMostly cloudy, with a low around 69°F20°C. Breezy from the NE at 11 to 12 mph18 to 19 km/h. 23% chance of showers throughout the night.
	SundayOct 4	72°F22°C	69°F20°C	0.25 in6.3 mm· 28%	59%	Showers	NE 12 mph19 km/h
DayMostly cloudy and warm, with a high of 72°F22°C. Breezy from the NE at 13 mph20 km/h. 28% chance of showers throughout the day. NightMostly cloudy, with a low around 69°F21°C. Breezy from the NE at 11 to 12 mph18 to 20 km/h. 24% chance of showers throughout the night.
	MondayOct 5	72°F22°C	68°F20°C	0.21 in5.4 mm· 23%	54%	Showers	NNE 13 mph21 km/h
DayMostly cloudy and warm, with a high of 72°F22°C. Breezy from the NNE at 13 to 14 mph22 to 22 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 69°F20°C. Breezy from the NE at 13 mph20 km/h. 22% chance of showers throughout the night.
	TuesdayOct 6	72°F22°C	68°F20°C	0.34 in8.7 mm· 23%	52%	Showers	NNE 14 mph22 km/h
DayMostly cloudy and warm, with a high of 72°F22°C. Breezy from the NNE at 14 mph22 km/h. 23% chance of showers throughout the day. NightMostly cloudy, with a low around 69°F20°C. Breezy from the NNE at 13 to 14 mph21 to 22 km/h. 23% chance of showers throughout the night.
	WednesdayOct 7	71°F22°C	68°F20°C	0.33 in8.5 mm· 27%	58%	Showers	NNE 14 mph22 km/h
DayMostly cloudy and warm, with a high of 71°F22°C. Breezy from the NNE at 14 mph23 km/h. 27% chance of showers throughout the day. NightMostly cloudy, with a low around 68°F20°C. Breezy from the NE at 14 mph22 km/h. 26% chance of showers throughout the night.
	ThursdayOct 8	71°F22°C	68°F20°C	0.26 in6.5 mm· 28%	58%	Showers	NNE 14 mph22 km/h
DayMostly cloudy and warm, with a high of 71°F22°C. Breezy from the NNE at 14 mph22 km/h. 28% chance of showers throughout the day. NightMostly cloudy, with a low around 68°F20°C. Breezy from the NNE at 13 mph22 km/h. 28% chance of showers throughout the night.

Nearby Cities

Ōhara1 mi2 km Katsuura8 mi12 km Mobara15 mi24 km Kamogawa20 mi31 km Ōamishirasato20 mi32 km Ōami20 mi33 km

About This Forecast

This forecast is powered by WeatherMesh, the world's most advanced and accurate weather model powered by AI. WeatherMesh is built on proprietary data from WindBorne's Global Sounding Balloon constellation — the world's largest fleet of autonomous, long-duration weather balloons — collecting observations across 100% of Earth, including over oceans and remote regions where no other data exists.

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Coordinates: 35.2300°N, 140.4049°E·Elevation: 1m·Timezone: Asia/Tokyo·Population: 35,544