Point Forecast: Mount St Helens WA  46.18N 122.18W (Elev. 1891 m)	Last Update: 11:41 am PDT May 18, 2024

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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 Haines Index Lightning Activity Level Trans. Wind  ktmphkm/hm/s

48-Hour Period Starting: 12pm Sat, May 18 20241pm Sat, May 18 20242pm Sat, May 18 20243pm Sat, May 18 20244pm Sat, May 18 20245pm Sat, May 18 20246pm Sat, May 18 20247pm Sat, May 18 20248pm Sat, May 18 20249pm Sat, May 18 202410pm Sat, May 18 202411pm Sat, May 18 202412am Sun, May 19 20241am Sun, May 19 20242am Sun, May 19 20243am Sun, May 19 20244am Sun, May 19 20245am Sun, May 19 20246am Sun, May 19 20247am Sun, May 19 20248am Sun, May 19 20249am Sun, May 19 202410am Sun, May 19 202411am Sun, May 19 202412pm Sun, May 19 20241pm Sun, May 19 20242pm Sun, May 19 20243pm Sun, May 19 20244pm Sun, May 19 20245pm Sun, May 19 20246pm Sun, May 19 20247pm Sun, May 19 20248pm Sun, May 19 20249pm Sun, May 19 202410pm Sun, May 19 202411pm Sun, May 19 202412am Mon, May 20 20241am Mon, May 20 20242am Mon, May 20 20243am Mon, May 20 20244am Mon, May 20 20245am Mon, May 20 20246am Mon, May 20 20247am Mon, May 20 20248am Mon, May 20 20249am Mon, May 20 202410am Mon, May 20 202411am Mon, May 20 202412pm Mon, May 20 20241pm Mon, May 20 20242pm Mon, May 20 20243pm Mon, May 20 20244pm Mon, May 20 20245pm Mon, May 20 20246pm Mon, May 20 20247pm Mon, May 20 20248pm Mon, May 20 20249pm Mon, May 20 202410pm Mon, May 20 202411pm Mon, May 20 202412am Tue, May 21 20241am Tue, May 21 20242am Tue, May 21 20243am Tue, May 21 20244am Tue, May 21 20245am Tue, May 21 20246am Tue, May 21 20247am Tue, May 21 20248am Tue, May 21 20249am Tue, May 21 202410am Tue, May 21 202411am Tue, May 21 202412pm Tue, May 21 20241pm Tue, May 21 20242pm Tue, May 21 20243pm Tue, May 21 20244pm Tue, May 21 20245pm Tue, May 21 20246pm Tue, May 21 20247pm Tue, May 21 20248pm Tue, May 21 20249pm Tue, May 21 202410pm Tue, May 21 202411pm Tue, May 21 202412am Wed, May 22 20241am Wed, May 22 20242am Wed, May 22 20243am Wed, May 22 20244am Wed, May 22 20245am Wed, May 22 20246am Wed, May 22 20247am Wed, May 22 20248am Wed, May 22 20249am Wed, May 22 202410am Wed, May 22 202411am Wed, May 22 202412pm Wed, May 22 20241pm Wed, May 22 20242pm Wed, May 22 20243pm Wed, May 22 20244pm Wed, May 22 20245pm Wed, May 22 20246pm Wed, May 22 20247pm Wed, May 22 20248pm Wed, May 22 20249pm Wed, May 22 202410pm Wed, May 22 202411pm Wed, May 22 2024

Date	05/18												05/19
Hour (PDT)	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11
Temperature (°C)	-1	-1	-1	-1	0	-1	-2	-2	-2	-2	-3	-3	-3	-3	-3	-3	-3	-3	-3	-2	-2	-2	-2	-2
Dewpoint (°C)	-4	-3	-3	-3	-2	-3	-3	-3	-4	-4	-4	-5	-4	-5	-6	-6	-6	-7	-6	-6	-6	-5	-5	-4
Heat Index (°C)
Surface Wind (mph)	5	17	17	18	21	25	26	31	25	23	25	23	23	23	20	20	20	17	17	17	15	15	15	14
Wind Dir	NW	WNW	WNW	WNW	WNW	WNW	WNW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW
Gust				29	29
Sky Cover (%)	58	68	75	83	87	83	72	68	62	70	62	61	64	62	67	67	66	65	64	67	70	67	65	59
Precipitation Potential (%)	12	28	46	68	74	74	55	46	32	24	18	12	9	8	8	9	12	15	14	18	17	18	19	24
Relative Humidity (%)	77	80	82	83	87	86	94	88	88	87	87	84	88	86	81	82	82	79	82	79	78	79	82	83
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	SChc	SChc	SChc	SChc	SChc	SChc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date													05/20
Hour (PDT)	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11
Temperature (°C)	-1	0	1	1	1	1	1	1	0	0	-1	-1	-1	-1	-1	-1	-1	-1	-1	-1	0	1	2	3
Dewpoint (°C)	-3	-3	-3	-3	-3	-2	-2	-3	-3	-4	-4	-4	-4	-5	-5	-6	-6	-6	-6	-5	-4	-4	-3	-3
Heat Index (°C)
Surface Wind (mph)	14	14	16	16	16	17	17	17	16	16	16	14	14	14	17	17	17	15	15	15	8	8	8	11
Wind Dir	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NNW	NNW	NNW	NNW	NNW	NNW	NW	NW	NW	WNW
Gust
Sky Cover (%)	58	61	67	63	61	52	52	52	54	54	54	30	30	30	23	23	23	32	32	32	31	31	31	17
Precipitation Potential (%)	35	42	51	45	41	6	6	6	6	6	6	0	0	0	0	0	0	0	0	0	0	0	0	3
Relative Humidity (%)	86	82	79	76	76	77	81	79	79	76	77	79	78	76	74	73	73	73	72	72	71	70	69	68
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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