Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Nagasao enjoys a temperate climate with an average annual temperature of 58°F (14°C). Winters average 39°F in January while summers reach 75°F in July. The area gets 240 sunny days per year, above the national average. Annual precipitation totals 52.9 inches (wetter than the 38-inch national average). The city sits at an elevation of 20 feet.
Temperature
39°F Jan (4°C)75°F Jul (24°C)
Annual Average
57.7°F
7% above US avg
January Average
39°F (4°C)
July Average
75°F (24°C)
Sunny Days
240 days/yr
Geography
Elevation
20 ft (6 m)
Area
28.2 sq mi (72.9 km²)
Population Density
292/sq mi
Coordinates
35.8833°N, 140.2833°W
Timezone
Asia/Tokyo
Precipitation & Snow
Annual Rainfall52.9"
39% above US avg
Snowfall0.0"
Wettest Month (Sep)7.24"
Driest Month (Jan)1.69"
Air Quality
Earthquake History
3,600 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M7.9.
Mar 11, 2011
47 km E of ?arai, Japan
M7.9
87 km
43 km
May 7, 2008
78 km NE of Hasaki, Japan
M6.9
116 km
27 km
Apr 11, 2011
17 km SSW of Ishikawa, Japan
M6.6
125 km
11 km
Mar 11, 2011
81 km NE of Hasaki, Japan
M6.5
119 km
7 km
Mar 11, 2011
92 km ENE of Hasaki, Japan
M6.3
138 km
21 km
Jul 30, 2011
13 km SSE of Iwaki, Japan
M6.3
132 km
38 km
Jun 1, 1990
near the east coast of Honshu, Japan
M6.3
41 km
67 km
May 7, 2008
80 km NE of Hasaki, Japan
M6.2
118 km
19 km
Jun 3, 2000
6 km SE of Narut?, Japan
M6.2
40 km
62 km
Mar 11, 2011
70 km ESE of Kitaibaraki, Japan
M6.2
132 km
40 km
Apr 21, 2011
6 km WNW of T?gane, Japan
M6.2
34 km
43 km
Apr 11, 2011
23 km SE of T?gane, Japan
M6.2
58 km
15 km
Sep 11, 1996
23 km SSE of Hasaki, Japan
M6.2
71 km
55 km
Aug 5, 1990
43 km E of ?arai, Japan
M6.1
85 km
27 km
May 26, 2023
12 km SE of Narutō, Japan
M6.1
45 km
42 km
Jun 5, 2012
75 km ESE of ?hara, Japan
M6.1
130 km
15 km
Mar 13, 2011
72 km E of Hasaki, Japan
M6.1
123 km
8 km
Sep 15, 2011
68 km E of ?arai, Japan
M6.1
104 km
28 km
May 7, 2008
95 km ENE of Hasaki, Japan
M6.1
136 km
23 km
Mar 14, 2012
5 km SE of Asahi, Japan
M6.0
43 km
10 km
Source: USGS Earthquake Catalog (M2.5+, 1990–2025). Sorted by magnitude.
Hurricane History
39 hurricanes (Category 1+) recorded within 500 km since 1980.
Strongest on record: Category 3.
Year
Name
Category
Max Wind
Closest
2025
Nakri
Category 1
—
287 km
2024
Ampil
Category 3
98 mph
184 km
2024
Jebi
Category 1
75 mph
209 km
2021
Mindulle
Category 1
86 mph
280 km
2019
Faxai
Category 3
98 mph
9 km
2019
Hagibis
Category 2
92 mph
86 km
2018
Jongdari
Category 2
86 mph
224 km
2018
Shanshan
Category 1
81 mph
141 km
2016
Mindulle
Category 1
75 mph
190 km
2016
Lionrock
Category 1
81 mph
209 km
2014
Phanfone
Category 1
75 mph
203 km
2011
Roke
Category 1
92 mph
98 km
2009
Krovanh
Category 1
69 mph
267 km
2007
Fitow
Category 1
81 mph
103 km
2005
Saola
Category 2
86 mph
251 km
2005
Mawar
Category 2
81 mph
20 km
2004
Ma-on
Category 3
92 mph
54 km
2003
Choi-wan
Category 3
81 mph
270 km
2002
Higos
Category 2
86 mph
35 km
2002
Phanfone
Category 1
75 mph
295 km
Source: NOAA IBTrACS (Category 1+, 1980–2026).
Tsunami History
20 tsunamis recorded within 500 km.
Highest wave on record: 13.0 m (43 ft).
Year
Location
Cause
Max Wave
Deaths
Distance
1923
SAGAMI BAY
Earthquake
13.0 m
105,385
112 km
1703
OFF SW BOSO PENINSULA
Earthquake
11.7 m
5,233
139 km
1677
OFF SE. BOSO PENINSULA
Earthquake
8.0 m
500
148 km
1495
KAMAKURA, SAGAMI BAY, TOKAIDO
Earthquake
5.0 m
200
112 km
1732
KUJUKURI BEACH, JAPAN
Earthquake
2.0 m
—
89 km
1670
BOSO, JAPAN
Earthquake
2.0 m
—
78 km
1433
OFF IZU-OSHIMA
Earthquake
2.0 m
—
130 km
1938
JAPAN TRENCH
Earthquake
0.8 m
—
135 km
1982
IBARAKI, JAPAN
Earthquake
0.4 m
—
132 km
1961
KASHIMA, JAPAN
Earthquake
0.4 m
—
146 km
1961
KASHIMA, JAPAN
Earthquake
0.4 m
—
150 km
1923
KASHIMA, JAPAN
Earthquake
0.4 m
—
147 km
1923
RYUKYU ISLANDS
Earthquake
0.3 m
—
110 km
1896
KASHIMA, JAPAN
Earthquake
0.3 m
—
94 km
1935
JAPAN
Earthquake
0.2 m
—
128 km
1855
TOKAIDO
Earthquake
—
6,757
51 km
1782
ODAWARA, SAGAMI BAY
Eruption + Earthquake
—
—
102 km
1642
BOSO, JAPAN
Earthquake
—
—
81 km
1633
SAGAMI BAY
Earthquake
—
150
124 km
1602
BOSO, JAPAN
Eruption + Earthquake
—
—
89 km
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
15 volcanoes within 200 km.
Closest: Nantaisan (121 km).
Name
Type
Elevation
Last Eruption
Distance
Nantaisan
Stratovolcano
2,486 m (8,156 ft)
-9540
121 km
Takaharayama
Stratovolcano
1,795 m (5,889 ft)
-4570
122 km
Omanago Group
Lava dome(s)
2,341 m (7,680 ft)
-3050
123 km
Akagisan
Stratovolcano
1,828 m (5,997 ft)
Unknown
123 km
Nikko-Shiranesan
Shield
2,578 m (8,458 ft)
1952
130 km
Hakoneyama
Complex
1,438 m (4,718 ft)
2015
135 km
Nasudake
Stratovolcano(es)
1,915 m (6,283 ft)
1963
141 km
Harunasan
Stratovolcano
1,449 m (4,754 ft)
550
145 km
Hiuchigatake
Stratovolcano
2,356 m (7,730 ft)
1544
149 km
Izu-Oshima
Stratovolcano
758 m (2,487 ft)
1990
152 km
Fujisan
Stratovolcano
3,776 m (12,388 ft)
1708
152 km
Izu-Tobu
Pyroclastic cone(s)
1,406 m (4,613 ft)
1989
153 km
Asamayama
Complex
2,568 m (8,425 ft)
2019
168 km
Toshima
Stratovolcano
508 m (1,667 ft)
-4550
177 km
Kusatsu-Shiranesan
Stratovolcano(es)
2,165 m (7,103 ft)
2018
177 km
Source: Smithsonian Institution Global Volcanism Program (GVP).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
39°F (4°C)
1.7 in
Coldest, Driest
February
40°F (4°C)
2.5 in
March
45°F (7°C)
3.8 in
April
55°F (13°C)
4.5 in
May
63°F (17°C)
4.7 in
June
69°F (20°C)
6.2 in
July
75°F (24°C)
5.0 in
August
78°F (26°C)
5.0 in
Warmest
September
72°F (22°C)
7.2 in
Wettest
October
62°F (17°C)
6.9 in
November
52°F (11°C)
3.5 in
December
43°F (6°C)
1.9 in
Nagasao has a seasonal temperature swing of 40°F / from 39°F in January to 78°F in August. Total annual precipitation is 52.9 inches, with September being the wettest month (7.2") and January the driest (1.7").