Point Forecast: Lewistown MT  47.07N 109.43W (Elev. 3898 ft)	Last Update: 5:21 pm MDT May 16, 2026

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Weather Elements Fire Weather Aviation Weather Temperature (°F) Dewpoint (°F) Wind Chill (°F) Surface Wind  ktmphkm/hm/s Sky Cover (%) Precipitation Potential (%) Relative Humidity (%) Rain Thunder Snow Freezing Rain Sleet Fog Mixing Height  x100ftx100m Trans. Wind  ktmphkm/hm/s Vent Rate (x1000 mph-ft) Grassland Fire Danger Index Ceiling Height Visibility

48-Hour Period Starting: 6pm Sat, May 16 20267pm Sat, May 16 20268pm Sat, May 16 20269pm Sat, May 16 202610pm Sat, May 16 202611pm Sat, May 16 202612am Sun, May 17 20261am Sun, May 17 20262am Sun, May 17 20263am Sun, May 17 20264am Sun, May 17 20265am Sun, May 17 20266am Sun, May 17 20267am Sun, May 17 20268am Sun, May 17 20269am Sun, May 17 202610am Sun, May 17 202611am Sun, May 17 202612pm Sun, May 17 20261pm Sun, May 17 20262pm Sun, May 17 20263pm Sun, May 17 20264pm Sun, May 17 20265pm Sun, May 17 20266pm Sun, May 17 20267pm Sun, May 17 20268pm Sun, May 17 20269pm Sun, May 17 202610pm Sun, May 17 202611pm Sun, May 17 202612am Mon, May 18 20261am Mon, May 18 20262am Mon, May 18 20263am Mon, May 18 20264am Mon, May 18 20265am Mon, May 18 20266am Mon, May 18 20267am Mon, May 18 20268am Mon, May 18 20269am Mon, May 18 202610am Mon, May 18 202611am Mon, May 18 202612pm Mon, May 18 20261pm Mon, May 18 20262pm Mon, May 18 20263pm Mon, May 18 20264pm Mon, May 18 20265pm Mon, May 18 20266pm Mon, May 18 20267pm Mon, May 18 20268pm Mon, May 18 20269pm Mon, May 18 202610pm Mon, May 18 202611pm Mon, May 18 202612am Tue, May 19 20261am Tue, May 19 20262am Tue, May 19 20263am Tue, May 19 20264am Tue, May 19 20265am Tue, May 19 20266am Tue, May 19 20267am Tue, May 19 20268am Tue, May 19 20269am Tue, May 19 202610am Tue, May 19 202611am Tue, May 19 202612pm Tue, May 19 20261pm Tue, May 19 20262pm Tue, May 19 20263pm Tue, May 19 20264pm Tue, May 19 20265pm Tue, May 19 20266pm Tue, May 19 20267pm Tue, May 19 20268pm Tue, May 19 20269pm Tue, May 19 202610pm Tue, May 19 202611pm Tue, May 19 202612am Wed, May 20 20261am Wed, May 20 20262am Wed, May 20 20263am Wed, May 20 20264am Wed, May 20 20265am Wed, May 20 20266am Wed, May 20 20267am Wed, May 20 20268am Wed, May 20 20269am Wed, May 20 202610am Wed, May 20 202611am Wed, May 20 202612pm Wed, May 20 20261pm Wed, May 20 20262pm Wed, May 20 20263pm Wed, May 20 20264pm Wed, May 20 20265pm Wed, May 20 20266pm Wed, May 20 20267pm Wed, May 20 20268pm Wed, May 20 20269pm Wed, May 20 202610pm Wed, May 20 202611pm Wed, May 20 202612am Thu, May 21 20261am Thu, May 21 20262am Thu, May 21 20263am Thu, May 21 20264am Thu, May 21 20265am Thu, May 21 2026

Date	05/16						05/17
Hour (MDT)	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17
Temperature (°F)	45	42	40	38	37	37	36	36	36	37	34	34	34	31	34	34	36	37	38	38	38	38	39	38
Dewpoint (°F)	39	36	36	35	35	35	34	34	33	34	31	31	31	29	32	32	33	32	33	32	32	32	33	32
Wind Chill (°F)	40	38	36	34	33	33	33	32	32	32	28	27	27	22	25	25	27	28	30	29	29	30	30	29
Surface Wind (mph)	9	7	6	5	5	5	3	5	5	6	7	8	8	10	13	14	14	15	14	16	16	14	16	16
Wind Dir	NNW	N	NNW	WNW	WNW	W	WNW	W	W	W	W	W	W	W	WNW	WNW	WNW	WNW	WNW	WNW	NW	NW	NW	NW
Gust														20	22	22	23	24	23	24	24	23	24	25
Sky Cover (%)	97	92	93	94	95	95	89	93	93	94	85	89	93	88	96	94	82	80	80	80	90	85	91	92
Precipitation Potential (%)	84	85	86	85	92	92	65	63	57	65	66	59	58	58	56	51	53	55	57	59	61	56	69	71
Relative Humidity (%)	78	79	84	89	93	93	93	92	90	90	89	89	90	93	93	91	87	83	81	79	80	79	79	80
Rain	Ocnl	Ocnl	--	--	--	--	Lkly	Lkly	Lkly	--	Lkly	Lkly	Lkly	Lkly	Lkly	Chc	Chc	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Snow	--	Ocnl	Ocnl	Ocnl	Ocnl	Ocnl	SChc	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly	Chc	Chc	--	Lkly	SChc	Lkly	--	Lkly	Lkly
Freezing Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Sleet	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date							05/18
Hour (MDT)	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17
Temperature (°F)	37	37	36	35	34	33	33	33	32	31	31	31	29	30	31	33	35	37	39	40	42	43	44	45
Dewpoint (°F)	31	31	31	31	31	31	31	31	30	29	30	30	28	29	30	30	31	31	31	30	31	31	31	31
Wind Chill (°F)	29	29	28	27	26	25	25	25	24	24	24	24	22	23	24	27	29	32	34	35	38	40	41	43
Surface Wind (mph)	13	13	13	10	10	10	9	9	9	7	7	7	7	7	7	7	7	7	7	7	7	5	5	5
Wind Dir	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NNW	NNW	NNW	NNW	NNW	NNW
Gust	22	22	22
Sky Cover (%)	97	97	97	91	91	91	87	87	87	95	95	95	100	100	100	89	89	89	75	75	75	72	72	72
Precipitation Potential (%)	63	63	62	37	37	37	45	45	45	52	52	51	39	39	39	39	39	39	20	20	20	20	20	20
Relative Humidity (%)	79	79	82	85	90	92	92	92	94	94	95	96	96	97	95	90	84	78	72	68	65	63	60	58
Rain	Lkly	Lkly	Lkly	Chc	Chc	Chc	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	SChc	SChc	SChc
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Snow	Lkly	Lkly	Lkly	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	SChc	SChc	SChc	--	--	--
Freezing Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Sleet	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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