Temperature, precipitation, air quality, natural hazards, and monthly weather data.
Ryūmaichō enjoys a temperate climate with an average annual temperature of 58°F (15°C). Winters average 38°F in January while summers reach 77°F in July. The area gets 247 sunny days per year, above the national average. Annual precipitation totals 48.9 inches (wetter than the 38-inch national average). The city sits at an elevation of 128 feet.
Temperature
38°F Jan (4°C)77°F Jul (25°C)
Annual Average
58.1°F
8% above US avg
January Average
38°F (4°C)
July Average
77°F (25°C)
Sunny Days
247 days/yr
Geography
Elevation
128 ft (39 m)
Area
67.4 sq mi (174.5 km²)
Population Density
130/sq mi
Coordinates
36.2833°N, 139.4167°W
Timezone
Asia/Tokyo
Precipitation & Snow
Annual Rainfall48.9"
29% above US avg
Snowfall0.0"
Wettest Month (Sep)7.28"
Driest Month (Jan)1.46"
Air Quality
Earthquake History
2,068 earthquakes (M2.5+) recorded within 150 km since 1990.
Strongest on record: M6.6.
Apr 11, 2011
17 km SSW of Ishikawa, Japan
M6.6
119 km
11 km
Jun 1, 1990
near the east coast of Honshu, Japan
M6.3
119 km
67 km
Mar 11, 2011
13 km E of Arai, Japan
M6.2
123 km
9 km
Apr 11, 2011
23 km SE of T?gane, Japan
M6.2
142 km
15 km
Apr 21, 2011
6 km WNW of T?gane, Japan
M6.2
112 km
43 km
Jun 3, 2000
6 km SE of Narut?, Japan
M6.2
125 km
62 km
May 26, 2023
12 km SE of Narutō, Japan
M6.1
131 km
42 km
Aug 5, 1990
43 km E of ?arai, Japan
M6.1
148 km
27 km
Mar 14, 2012
5 km SE of Asahi, Japan
M6.0
133 km
10 km
Apr 3, 2004
37 km ESE of Hitachi, Japan
M6.0
143 km
31 km
Jul 20, 2000
31 km ESE of Hitachi, Japan
M6.0
142 km
47 km
Mar 11, 2011
4 km ESE of Hasaki, Japan
M6.0
146 km
48 km
Mar 15, 2011
6 km NNW of Fujinomiya, Japan
M6.0
135 km
9 km
Jul 23, 2005
9 km WSW of Ichihara, Japan
M5.9
101 km
61 km
Apr 10, 2005
near the east coast of Honshu, Japan
M5.9
116 km
43 km
Apr 12, 2011
8 km WSW of Ishikawa, Japan
M5.9
125 km
11 km
Feb 1, 1992
4 km SSE of Miura, Japan
M5.8
133 km
100 km
Apr 16, 2011
6 km ENE of Tanuma, Japan
M5.8
24 km
77 km
Feb 25, 2013
29 km NE of Numata, Japan
M5.8
64 km
10 km
May 20, 2011
3 km NNE of Hasaki, Japan
M5.8
141 km
29 km
Source: USGS Earthquake Catalog (M2.5+, 1990-2025). Sorted by magnitude.
Hurricane History
31 hurricanes (Category 1+) recorded within 500 km since 1980.
Strongest on record: Category 3.
Year
Name
Category
Max Wind
Closest
2024
Ampil
Category 3
98 mph
274 km
2024
Jebi
Category 1
75 mph
289 km
2019
Faxai
Category 3
98 mph
96 km
2019
Hagibis
Category 2
92 mph
76 km
2018
Jebi
Category 1
81 mph
275 km
2018
Shanshan
Category 1
75 mph
225 km
2018
Jongdari
Category 1
81 mph
253 km
2016
Lionrock
Category 1
75 mph
289 km
2016
Mindulle
Category 1
75 mph
221 km
2014
Phanfone
Category 1
81 mph
179 km
2011
Roke
Category 2
92 mph
47 km
2007
Fitow
Category 1
81 mph
78 km
2005
Mawar
Category 2
81 mph
103 km
2004
Ma-on
Category 3
92 mph
84 km
2003
Etau
Category 1
52 mph
299 km
2002
Higos
Category 2
86 mph
61 km
2001
Danas
Category 1
81 mph
69 km
2000
Kirogi
Category 1
86 mph
159 km
1998
Vicki
Category 2
69 mph
178 km
1998
Stella
Category 1
69 mph
27 km
Source: NOAA IBTrACS (Category 1+, 1980-2026).
Tsunami History
9 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
132 km
1495
KAMAKURA, SAGAMI BAY, TOKAIDO
Earthquake
5.0 m
200
132 km
1896
KASHIMA, JAPAN
Earthquake
0.3 m
-
144 km
1855
TOKAIDO
Earthquake
-
6,757
78 km
1782
ODAWARA, SAGAMI BAY
Eruption + Earthquake
-
-
134 km
1633
SAGAMI BAY
Earthquake
-
150
122 km
1257
SAGAMI BAY, JAPAN
Earthquake
-
-
121 km
1241
KAMAKURA, SAGAMI BAY
Earthquake
-
-
121 km
818
TOKAIDO
Eruption + Earthquake
-
-
121 km
Source: NOAA/NCEI Historical Tsunami Database.
Nearby Volcanoes
15 volcanoes within 200 km.
Closest: Akagisan (37 km).
Name
Type
Elevation
Last Eruption
Distance
Akagisan
Stratovolcano
1,828 m (5,997 ft)
Unknown
37 km
Nantaisan
Stratovolcano
2,486 m (8,156 ft)
-9540
54 km
Harunasan
Stratovolcano
1,449 m (4,754 ft)
550
55 km
Nikko-Shiranesan
Shield
2,578 m (8,458 ft)
1952
58 km
Omanago Group
Lava dome(s)
2,341 m (7,680 ft)
-3050
58 km
Hiuchigatake
Stratovolcano
2,356 m (7,730 ft)
1544
76 km
Takaharayama
Stratovolcano
1,795 m (5,889 ft)
-4570
76 km
Asamayama
Complex
2,568 m (8,425 ft)
2019
81 km
Kusatsu-Shiranesan
Stratovolcano(es)
2,165 m (7,103 ft)
2018
88 km
Shiga
Shield(s)
2,041 m (6,696 ft)
Unknown
92 km
Yokodake
Stratovolcano(es)
2,480 m (8,136 ft)
1200
101 km
Nasudake
Stratovolcano(es)
1,915 m (6,283 ft)
1963
106 km
Fujisan
Stratovolcano
3,776 m (12,388 ft)
1708
120 km
Hakoneyama
Complex
1,438 m (4,718 ft)
2015
122 km
Numazawa
Shield
835 m (2,740 ft)
-3400
130 km
Source: Smithsonian Institution Global Volcanism Program (GVP).
Monthly Weather
Month
Avg Temperature
Precipitation
Summary
January
38°F (4°C)
1.5 in
Coldest, Driest
February
40°F (4°C)
2.0 in
March
45°F (7°C)
2.7 in
April
56°F (13°C)
3.6 in
May
64°F (18°C)
4.3 in
June
70°F (21°C)
6.5 in
July
77°F (25°C)
5.6 in
August
79°F (26°C)
6.2 in
Warmest
September
72°F (22°C)
7.3 in
Wettest
October
62°F (16°C)
5.2 in
November
52°F (11°C)
2.6 in
December
43°F (6°C)
1.5 in
Ryūmaichō has a seasonal temperature swing of 41°F / from 38°F in January to 79°F in August. Total annual precipitation is 49.0 inches, with September being the wettest month (7.3") and January the driest (1.5").