Point Forecast: Mount St Helens WA  46.18N 122.18W (Elev. 1891 m)	Last Update: 10:42 am PDT May 10, 2026

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Weather Elements Weather/Precipitation Fire Weather Temperature (°C) Dewpoint (°C) Heat Index (°C) Surface Wind  ktmphkm/hm/s Sky Cover (%) Precipitation Potential (%) Relative Humidity (%) Rain Thunder Fog Mixing Height  x100ftx100m Trans. Wind  ktmphkm/hm/s

48-Hour Period Starting: 11am Sun, May 10 202612pm Sun, May 10 20261pm Sun, May 10 20262pm Sun, May 10 20263pm Sun, May 10 20264pm Sun, May 10 20265pm Sun, May 10 20266pm Sun, May 10 20267pm Sun, May 10 20268pm Sun, May 10 20269pm Sun, May 10 202610pm Sun, May 10 202611pm Sun, May 10 202612am Mon, May 11 20261am Mon, May 11 20262am Mon, May 11 20263am Mon, May 11 20264am Mon, May 11 20265am Mon, May 11 20266am Mon, May 11 20267am Mon, May 11 20268am Mon, May 11 20269am Mon, May 11 202610am Mon, May 11 202611am Mon, May 11 202612pm Mon, May 11 20261pm Mon, May 11 20262pm Mon, May 11 20263pm Mon, May 11 20264pm Mon, May 11 20265pm Mon, May 11 20266pm Mon, May 11 20267pm Mon, May 11 20268pm Mon, May 11 20269pm Mon, May 11 202610pm Mon, May 11 202611pm Mon, May 11 202612am Tue, May 12 20261am Tue, May 12 20262am Tue, May 12 20263am Tue, May 12 20264am Tue, May 12 20265am Tue, May 12 20266am Tue, May 12 20267am Tue, May 12 20268am Tue, May 12 20269am Tue, May 12 202610am Tue, May 12 202611am Tue, May 12 202612pm Tue, May 12 20261pm Tue, May 12 20262pm Tue, May 12 20263pm Tue, May 12 20264pm Tue, May 12 20265pm Tue, May 12 20266pm Tue, May 12 20267pm Tue, May 12 20268pm Tue, May 12 20269pm Tue, May 12 202610pm Tue, May 12 202611pm Tue, May 12 202612am Wed, May 13 20261am Wed, May 13 20262am Wed, May 13 20263am Wed, May 13 20264am Wed, May 13 20265am Wed, May 13 20266am Wed, May 13 20267am Wed, May 13 20268am Wed, May 13 20269am Wed, May 13 202610am Wed, May 13 202611am Wed, May 13 202612pm Wed, May 13 20261pm Wed, May 13 20262pm Wed, May 13 20263pm Wed, May 13 20264pm Wed, May 13 20265pm Wed, May 13 20266pm Wed, May 13 20267pm Wed, May 13 20268pm Wed, May 13 20269pm Wed, May 13 202610pm Wed, May 13 202611pm Wed, May 13 202612am Thu, May 14 20261am Thu, May 14 20262am Thu, May 14 20263am Thu, May 14 20264am Thu, May 14 20265am Thu, May 14 20266am Thu, May 14 20267am Thu, May 14 20268am Thu, May 14 20269am Thu, May 14 202610am Thu, May 14 202611am Thu, May 14 202612pm Thu, May 14 20261pm Thu, May 14 20262pm Thu, May 14 20263pm Thu, May 14 20264pm Thu, May 14 20265pm Thu, May 14 20266pm Thu, May 14 20267pm Thu, May 14 20268pm Thu, May 14 20269pm Thu, May 14 202610pm Thu, May 14 2026

Date	05/10													05/11
Hour (PDT)	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10
Temperature (°C)	7	7	7	7	7	7	6	6	6	5	4	4	3	3	3	2	2	2	1	2	3	4	7	8
Dewpoint (°C)	2	3	3	3	2	3	1	1	2	1	1	0	0	1	1	0	0	-1	-2	-2	-2	-2	-2	-2
Heat Index (°C)
Surface Wind (mph)	14	16	17	18	21	23	24	24	23	18	15	13	9	9	9	9	10	10	9	9	9	6	6	6
Wind Dir	WSW	W	W	W	W	WNW	WNW	WNW	WNW	WNW	NW	NW	WNW	NW	NW	NNW	NNW	NNW	N	N	N	ENE	ENE	ENE
Gust						29	30	30	29
Sky Cover (%)	80	78	57	44	42	46	48	55	49	33	28	17	19	32	28	29	27	39	38	38	38	25	25	25
Precipitation Potential (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	73	75	76	75	70	72	70	71	72	74	76	77	80	86	85	86	84	82	80	76	70	65	54	50
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date														05/12
Hour (PDT)	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10
Temperature (°C)	9	11	11	11	12	12	12	12	12	11	10	9	9	8	8	8	8	8	8	8	9	11	12	13
Dewpoint (°C)	-2	-1	-1	-2	-2	-1	-1	-1	1	2	1	-1	-2	-3	-3	-4	-5	-6	-7	-6	-5	-4	-4	-3
Heat Index (°C)
Surface Wind (mph)	7	7	7	8	8	8	8	8	8	7	7	7	13	13	13	15	15	15	17	17	17	18	18	18
Wind Dir	SE	SE	SE	S	S	S	SSW	SSW	SSW	N	N	N	NE	NE	NE	ENE	ENE	ENE	ENE	ENE	ENE	E	E	E
Gust
Sky Cover (%)	13	13	13	8	8	8	13	13	13	10	10	10	15	15	15	28	28	28	43	43	43	44	44	44
Precipitation Potential (%)	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	45	45	43	41	39	39	39	42	47	52	52	49	46	45	43	42	40	37	35	35	35	35	34	34
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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