Point Forecast: 2 Miles ESE Great Falls VA  39N 77.26W (Elev. 259 ft)	Last Update: 10:53 am EDT Sep 4, 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: 11am Fri, Sep 4 202612pm Fri, Sep 4 20261pm Fri, Sep 4 20262pm Fri, Sep 4 20263pm Fri, Sep 4 20264pm Fri, Sep 4 20265pm Fri, Sep 4 20266pm Fri, Sep 4 20267pm Fri, Sep 4 20268pm Fri, Sep 4 20269pm Fri, Sep 4 202610pm Fri, Sep 4 202611pm Fri, Sep 4 202612am Sat, Sep 5 20261am Sat, Sep 5 20262am Sat, Sep 5 20263am Sat, Sep 5 20264am Sat, Sep 5 20265am Sat, Sep 5 20266am Sat, Sep 5 20267am Sat, Sep 5 20268am Sat, Sep 5 20269am Sat, Sep 5 202610am Sat, Sep 5 202611am Sat, Sep 5 202612pm Sat, Sep 5 20261pm Sat, Sep 5 20262pm Sat, Sep 5 20263pm Sat, Sep 5 20264pm Sat, Sep 5 20265pm Sat, Sep 5 20266pm Sat, Sep 5 20267pm Sat, Sep 5 20268pm Sat, Sep 5 20269pm Sat, Sep 5 202610pm Sat, Sep 5 202611pm Sat, Sep 5 202612am Sun, Sep 6 20261am Sun, Sep 6 20262am Sun, Sep 6 20263am Sun, Sep 6 20264am Sun, Sep 6 20265am Sun, Sep 6 20266am Sun, Sep 6 20267am Sun, Sep 6 20268am Sun, Sep 6 20269am Sun, Sep 6 202610am Sun, Sep 6 202611am Sun, Sep 6 202612pm Sun, Sep 6 20261pm Sun, Sep 6 20262pm Sun, Sep 6 20263pm Sun, Sep 6 20264pm Sun, Sep 6 20265pm Sun, Sep 6 20266pm Sun, Sep 6 20267pm Sun, Sep 6 20268pm Sun, Sep 6 20269pm Sun, Sep 6 202610pm Sun, Sep 6 202611pm Sun, Sep 6 202612am Mon, Sep 7 20261am Mon, Sep 7 20262am Mon, Sep 7 20263am Mon, Sep 7 20264am Mon, Sep 7 20265am Mon, Sep 7 20266am Mon, Sep 7 20267am Mon, Sep 7 20268am Mon, Sep 7 20269am Mon, Sep 7 202610am Mon, Sep 7 202611am Mon, Sep 7 202612pm Mon, Sep 7 20261pm Mon, Sep 7 20262pm Mon, Sep 7 20263pm Mon, Sep 7 20264pm Mon, Sep 7 20265pm Mon, Sep 7 20266pm Mon, Sep 7 20267pm Mon, Sep 7 20268pm Mon, Sep 7 20269pm Mon, Sep 7 202610pm Mon, Sep 7 202611pm Mon, Sep 7 202612am Tue, Sep 8 20261am Tue, Sep 8 20262am Tue, Sep 8 20263am Tue, Sep 8 20264am Tue, Sep 8 20265am Tue, Sep 8 20266am Tue, Sep 8 20267am Tue, Sep 8 20268am Tue, Sep 8 20269am Tue, Sep 8 202610am Tue, Sep 8 202611am Tue, Sep 8 202612pm Tue, Sep 8 20261pm Tue, Sep 8 20262pm Tue, Sep 8 20263pm Tue, Sep 8 20264pm Tue, Sep 8 20265pm Tue, Sep 8 20266pm Tue, Sep 8 20267pm Tue, Sep 8 20268pm Tue, Sep 8 20269pm Tue, Sep 8 202610pm Tue, Sep 8 2026

Date	09/04													09/05
Hour (EDT)	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 (°F)	84	86	88	88	87	86	84	82	81	79	78	77	76	75	74	74	73	73	73	72	71	73	73	76
Dewpoint (°F)	74	74	74	74	74	73	73	72	72	71	71	71	71	71	70	71	70	70	70	69	69	70	71	70
Heat Index (°F)	91	94	97	97	95	93	90	87	85	79	78	77	76	75										76
Surface Wind (mph)	7	7	8	8	8	8	8	7	6	5	3	3	3	3	3	3	3	5	5	5	3	3	5	5
Wind Dir	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	W	NW	NW	NW	NW	NW	NW	N	N	N	N	N
Gust					18		18
Sky Cover (%)	18	27	41	62	72	70	67	67	71	74	75	71	70	65	65	60	45	49	64	68	72	77	75	76
Precipitation Potential (%)	1	1	2	11	21	55	43	53	43	37	23	16	10	7	8	4	5	6	7	0	15	12	16	11
Relative Humidity (%)	72	68	63	63	65	65	70	72	74	77	79	82	85	87	87	90	90	90	90	90	93	90	93	82
Rain	--	--	--	--	SChc	Lkly	Chc	Chc	Chc	Chc	SChc	SChc	--	--	--	--	--	--	--	--	SChc	--	SChc	--
Thunder	--	--	--	--	SChc	SChc	Chc	Chc	Chc	SChc	SChc	SChc	--	--	--	--	--	--	--	--	SChc	--	--	--
Date														09/06
Hour (EDT)	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 (°F)	78	79	80	81	81	82	81	80	79	75	73	72	71	70	69	68	67	66	66	65	64	65	68	71
Dewpoint (°F)	70	71	71	71	71	71	71	70	69	68	67	66	66	65	65	64	64	63	63	63	63	63	64	64
Heat Index (°F)	78	79	83	85	85	86	85	83	79	75
Surface Wind (mph)	5	6	5	6	6	5	6	5	5	3	2	2	2	2	3	3	3	5	5	5	6	6	6	6
Wind Dir	N	N	N	N	N	N	N	N	N	N	NE	NE	NE	NE	N	N	N	N	N	N	NE	NE	NE	NE
Gust
Sky Cover (%)	65	60	63	64	56	65	63	58	61	39	58	52	45	41	37	33	33	33	33	29	25	21	23	24
Precipitation Potential (%)	6	6	3	0	10	18	21	37	41	10	10	10	10	10	10	2	2	2	2	2	2	3	3	3
Relative Humidity (%)	76	77	74	72	72	69	72	72	72	79	81	81	84	84	87	87	90	90	90	93	97	93	87	79
Rain	--	--	--	--	--	SChc	SChc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	SChc	SChc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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