Mount Sumon

守門岳

Sanjō-shi, Niigata · Elevation 1,537 m

Mount Sumon is a Quaternary volcanic massif straddling Uonuma, Sanjō, and Nagaoka Cities in Niigata Prefecture, consisting of three peaks — Hakama-dake (the 1,537.2 m summit), Aogumo-dake, and Ō-dake — that together form one of Echigo's signature ranges. It is listed in the Nihon Nihyaku Meizan, the Shin Hana no Hyakumeizan, and the Echigo 100 Meizan, and its slopes carry a beech forest with trees over 300 years old. In early summer the upper ridges fill with Himesayuri lilies, Nikkō-kisuge day lilies, and Shirane-aoi. From late winter into spring, the northeast face of Ō-dake develops a vast cornice often called the largest in East Asia, drawing photographers and ski-mountaineers. The principal trailheads — Hokyūrei, Futakuchi, and Ōhara on the Uonuma side, Yoshigahira on the Sanjō side, and Iri-shiokawa on the Tochio (Nagaoka) side — typically open between late May and June each year.

Mount Sumon at a glance

Weather: The most settled day in the next 7 days is Wed, November 4: clear, gusts up to 7 m/s. Fri, Nov 6, Sat, Nov 7: strong wind (gusts up to 22 m/s).
Route: The shortest is Mount Sumon (Mount Hakama) Return from Hokkure via Mount Odake and Mount Seiun: about 6 h 27 min, 9.7 km, about 1,090 m of climbing.

Mount Sumon weather (hourly, 14 days)

Sunrise today 06:09, sunset 16:45

		Tue, 11/3					Wed, 11/4										Thu, 11/5								Fri, 11/6								Sat, 11/7								Sun, 11/8								Mon, 11/9						Tue, 11/10				Wed, 11/11				Thu, 11/12				Fri, 11/13				Sat, 11/14				Sun, 11/15				Mon, 11/16				Tue, 11/17
Japan time		15	17	19	21	23	1	3	5	7	9	11	13	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	12	15	18	21	0	3	6	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15	21	3	9	15

Temperature	°C	4°	0°	0°	-2°	-3°	-3°	-2°	-2°	0°	5°	7°	9°	8°	3°	2°	2°	2°	3°	5°	7°	9°	5°	7°	5°	4°	5°	6°	6°	6°	3°	2°	0°	0°	-2°	-2°	-2°	-2°	-3°	-3°	-3°	-3°	-3°	-1°	1°	0°	-1°	-2°	-2°	-3°	-3°	0°	1°	-2°	-5°	1°	7°	1°	-4°	-1°	-1°	-2°	-2°	0°	1°	-3°	-1°	-1°	-1°	-2°	-3°	1°	4°	-4°	-4°	5°	7°	2°	2°	5°	2°	-3°	-4°	-1°	1°
Precipitation	mm																	6	11	2.4	1.3				0.2		2.3	3.8	5	0.9	1.7	3.0	3.7	5	8	7	4.1	1.8	1.3	1.1	0.8	1.5	1.1	0.7	0.9	0.5	0.2	0.2	0.3	0.9	0.7	0.1		0.1				1.4	12	5	3.0	1.8	0.5	0.4	0.9		2.7	14	0.2									4.2	4.8	3.9	7	4.6	0.2
New snow	cm																																			<.1	<.1	<.1	<.1																				1.9	3.6
Snow depth	cm	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	2	<1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Wind	m/s	3	1	0	0	0	0	0	0	0	1	1	2	3	3	3	3	3	2	3	2	1	1	2	1	0	2	4	5	6	5	5	3	4	5	5	6	6	5	5	4	4	3	3	5	3	1	0	1	1	2	1	2	1	1	2	2	2	2	4	5	2	1	2	3	1	3	3	4	2	0	0	2	1	1	1	1	3	2	3	6	4	1	1	2
Wind gusts	m/s	12	10	5	4	3	3	3	3	2	4	5	6	7	8	7	9	9	9	9	7	6	4	6	5	4	7	14	17	18	19	16	16	17	17	18	21	22	19	16	15	14	13	11	14	14	9	4	3	3	4	4	8	7	3	7	8	10	16	22	20	15	8	7	10	9	13	11	13	12	6	3	7	6	3	4	5	9	7	9	16	17	12	5	7
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