Point Forecast: 2 Miles ESE Great Falls VA  39N 77.26W (Elev. 259 ft)	Last Update: 7:53 am EDT Aug 7, 2026

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Weather Elements Fire Weather Aviation Weather Temperature (°F) Dewpoint (°F) Heat Index (°F) Surface Wind  ktmphkm/hm/s Sky Cover (%) Precipitation Potential (%) Relative Humidity (%) Rain Thunder Fog Mixing Height  x100ftx100m Trans. Wind  ktmphkm/hm/s Vent Rate (x1000 mph-ft) Atmospheric Dispersion Index Low Visibility Occurrence Risk Index Ceiling Height Visibility

48-Hour Period Starting: 8am Fri, Aug 7 20269am Fri, Aug 7 202610am Fri, Aug 7 202611am Fri, Aug 7 202612pm Fri, Aug 7 20261pm Fri, Aug 7 20262pm Fri, Aug 7 20263pm Fri, Aug 7 20264pm Fri, Aug 7 20265pm Fri, Aug 7 20266pm Fri, Aug 7 20267pm Fri, Aug 7 20268pm Fri, Aug 7 20269pm Fri, Aug 7 202610pm Fri, Aug 7 202611pm Fri, Aug 7 202612am Sat, Aug 8 20261am Sat, Aug 8 20262am Sat, Aug 8 20263am Sat, Aug 8 20264am Sat, Aug 8 20265am Sat, Aug 8 20266am Sat, Aug 8 20267am Sat, Aug 8 20268am Sat, Aug 8 20269am Sat, Aug 8 202610am Sat, Aug 8 202611am Sat, Aug 8 202612pm Sat, Aug 8 20261pm Sat, Aug 8 20262pm Sat, Aug 8 20263pm Sat, Aug 8 20264pm Sat, Aug 8 20265pm Sat, Aug 8 20266pm Sat, Aug 8 20267pm Sat, Aug 8 20268pm Sat, Aug 8 20269pm Sat, Aug 8 202610pm Sat, Aug 8 202611pm Sat, Aug 8 202612am Sun, Aug 9 20261am Sun, Aug 9 20262am Sun, Aug 9 20263am Sun, Aug 9 20264am Sun, Aug 9 20265am Sun, Aug 9 20266am Sun, Aug 9 20267am Sun, Aug 9 20268am Sun, Aug 9 20269am Sun, Aug 9 202610am Sun, Aug 9 202611am Sun, Aug 9 202612pm Sun, Aug 9 20261pm Sun, Aug 9 20262pm Sun, Aug 9 20263pm Sun, Aug 9 20264pm Sun, Aug 9 20265pm Sun, Aug 9 20266pm Sun, Aug 9 20267pm Sun, Aug 9 20268pm Sun, Aug 9 20269pm Sun, Aug 9 202610pm Sun, Aug 9 202611pm Sun, Aug 9 202612am Mon, Aug 10 20261am Mon, Aug 10 20262am Mon, Aug 10 20263am Mon, Aug 10 20264am Mon, Aug 10 20265am Mon, Aug 10 20266am Mon, Aug 10 20267am Mon, Aug 10 20268am Mon, Aug 10 20269am Mon, Aug 10 202610am Mon, Aug 10 202611am Mon, Aug 10 202612pm Mon, Aug 10 20261pm Mon, Aug 10 20262pm Mon, Aug 10 20263pm Mon, Aug 10 20264pm Mon, Aug 10 20265pm Mon, Aug 10 20266pm Mon, Aug 10 20267pm Mon, Aug 10 20268pm Mon, Aug 10 20269pm Mon, Aug 10 202610pm Mon, Aug 10 202611pm Mon, Aug 10 202612am Tue, Aug 11 20261am Tue, Aug 11 20262am Tue, Aug 11 20263am Tue, Aug 11 20264am Tue, Aug 11 20265am Tue, Aug 11 20266am Tue, Aug 11 20267am Tue, Aug 11 20268am Tue, Aug 11 20269am Tue, Aug 11 202610am Tue, Aug 11 202611am Tue, Aug 11 202612pm Tue, Aug 11 20261pm Tue, Aug 11 20262pm Tue, Aug 11 20263pm Tue, Aug 11 20264pm Tue, Aug 11 20265pm Tue, Aug 11 20266pm Tue, Aug 11 20267pm Tue, Aug 11 2026

Date	08/07																08/08
Hour (EDT)	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07
Temperature (°F)	75	77	80	83	85	87	89	88	88	88	86	83	80	79	77	77	75	75	74	73	73	72	72	73
Dewpoint (°F)	71	72	73	73	72	71	71	71	71	71	71	72	72	73	72	72	71	72	72	72	72	71	72	72
Heat Index (°F)	75	77	84	89	91	93	95	94	94	94	91	88	84	79	77	77	75	75
Surface Wind (mph)	2	2	3	3	5	5	6	7	7	7	7	5	3	2	2	2	2	2	2	2	2	2	2	2
Wind Dir	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	W	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW
Gust
Sky Cover (%)	40	40	44	37	38	39	38	51	63	66	69	61	67	64	53	57	64	53	42	52	46	45	50	43
Precipitation Potential (%)	4	4	3	4	5	10	20	26	44	46	43	34	22	13	8	7	6	5	0	0	0	0	0	1
Relative Humidity (%)	87	85	79	72	65	59	56	57	57	57	61	70	77	82	85	85	87	90	93	97	97	97	100	97
Rain	--	--	--	--	--	--	SChc	Chc	Chc	Chc	Chc	Chc	SChc	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	SChc	Chc	Chc	Chc	Chc	Chc	SChc	--	--	--	--	--	--	--	--	--	--	--
Date																	08/09
Hour (EDT)	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07
Temperature (°F)	74	77	80	84	86	88	89	89	88	88	85	84	81	79	78	76	75	75	75	74	74	73	73	74
Dewpoint (°F)	72	74	74	74	74	74	73	73	73	73	73	72	73	73	72	72	72	71	71	71	71	71	71	72
Heat Index (°F)		77	84	91	94	97	97	97	96	96	92	90	86	79	78	76	75	75	75
Surface Wind (mph)	2	2	3	5	6	7	7	7	7	7	6	6	5	5	3	3	3	2	1	1	1	2	2	3
Wind Dir	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	SW	W	SW	SW	W	W	W	W
Gust
Sky Cover (%)	38	34	31	33	42	51	60	71	63	64	68	64	46	51	47	46	39	36	32	35	38	40	37	34
Precipitation Potential (%)	3	3	0	0	1	1	36	57	43	29	34	43	13	13	13	13	13	13	1	1	1	1	1	1
Relative Humidity (%)	93	90	82	72	68	63	59	59	61	61	67	67	77	82	82	87	90	87	87	90	90	93	93	93
Rain	--	--	--	--	--	--	Chc	Lkly	Chc	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	Chc	Chc	Chc	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--

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