Point Forecast: Herndon VA  38.97N 77.38W (Elev. 354 ft)	Last Update: 7:31 am EDT Sep 7, 2024

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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 Haines Index Lightning Activity Level 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: 7am Sat, Sep 7 20248am Sat, Sep 7 20249am Sat, Sep 7 202410am Sat, Sep 7 202411am Sat, Sep 7 202412pm Sat, Sep 7 20241pm Sat, Sep 7 20242pm Sat, Sep 7 20243pm Sat, Sep 7 20244pm Sat, Sep 7 20245pm Sat, Sep 7 20246pm Sat, Sep 7 20247pm Sat, Sep 7 20248pm Sat, Sep 7 20249pm Sat, Sep 7 202410pm Sat, Sep 7 202411pm Sat, Sep 7 202412am Sun, Sep 8 20241am Sun, Sep 8 20242am Sun, Sep 8 20243am Sun, Sep 8 20244am Sun, Sep 8 20245am Sun, Sep 8 20246am Sun, Sep 8 20247am Sun, Sep 8 20248am Sun, Sep 8 20249am Sun, Sep 8 202410am Sun, Sep 8 202411am Sun, Sep 8 202412pm Sun, Sep 8 20241pm Sun, Sep 8 20242pm Sun, Sep 8 20243pm Sun, Sep 8 20244pm Sun, Sep 8 20245pm Sun, Sep 8 20246pm Sun, Sep 8 20247pm Sun, Sep 8 20248pm Sun, Sep 8 20249pm Sun, Sep 8 202410pm Sun, Sep 8 202411pm Sun, Sep 8 202412am Mon, Sep 9 20241am Mon, Sep 9 20242am Mon, Sep 9 20243am Mon, Sep 9 20244am Mon, Sep 9 20245am Mon, Sep 9 20246am Mon, Sep 9 20247am Mon, Sep 9 20248am Mon, Sep 9 20249am Mon, Sep 9 202410am Mon, Sep 9 202411am Mon, Sep 9 202412pm Mon, Sep 9 20241pm Mon, Sep 9 20242pm Mon, Sep 9 20243pm Mon, Sep 9 20244pm Mon, Sep 9 20245pm Mon, Sep 9 20246pm Mon, Sep 9 20247pm Mon, Sep 9 20248pm Mon, Sep 9 20249pm Mon, Sep 9 202410pm Mon, Sep 9 202411pm Mon, Sep 9 202412am Tue, Sep 10 20241am Tue, Sep 10 20242am Tue, Sep 10 20243am Tue, Sep 10 20244am Tue, Sep 10 20245am Tue, Sep 10 20246am Tue, Sep 10 20247am Tue, Sep 10 20248am Tue, Sep 10 20249am Tue, Sep 10 202410am Tue, Sep 10 202411am Tue, Sep 10 202412pm Tue, Sep 10 20241pm Tue, Sep 10 20242pm Tue, Sep 10 20243pm Tue, Sep 10 20244pm Tue, Sep 10 20245pm Tue, Sep 10 20246pm Tue, Sep 10 20247pm Tue, Sep 10 20248pm Tue, Sep 10 20249pm Tue, Sep 10 202410pm Tue, Sep 10 202411pm Tue, Sep 10 202412am Wed, Sep 11 20241am Wed, Sep 11 20242am Wed, Sep 11 20243am Wed, Sep 11 20244am Wed, Sep 11 20245am Wed, Sep 11 20246am Wed, Sep 11 20247am Wed, Sep 11 20248am Wed, Sep 11 20249am Wed, Sep 11 202410am Wed, Sep 11 202411am Wed, Sep 11 202412pm Wed, Sep 11 20241pm Wed, Sep 11 20242pm Wed, Sep 11 20243pm Wed, Sep 11 20244pm Wed, Sep 11 20245pm Wed, Sep 11 20246pm Wed, Sep 11 2024

Date	09/07																	09/08
Hour (EDT)	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06
Temperature (°F)	65	65	65	68	69	67	67	68	66	67	67	66	65	62	60	59	57	56	55	54	53	51	50	49
Dewpoint (°F)	62	63	64	64	62	61	59	58	58	57	56	55	53	52	51	50	50	49	49	48	48	47	47	47
Heat Index (°F)
Surface Wind (mph)	6	6	6	8	10	10	10	10	10	9	9	8	7	7	7	8	8	8	8	8	8	8	8	7
Wind Dir	S	S	SW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW
Gust						18	20	21	21	18
Sky Cover (%)	77	79	81	83	85	85	86	86	73	61	48	37	27	16	12	8	4	4	3	2	2	2	2	1
Precipitation Potential (%)	0	0	2	3	22	18	25	23	16	6	4	3	1	1	1	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	90	93	97	87	78	81	75	70	75	70	68	68	65	70	72	72	77	77	80	80	83	86	89	93
Rain	--	--	--	--	SChc	SChc	Chc	SChc	SChc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date																		09/09
Hour (EDT)	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06
Temperature (°F)	48	50	54	58	61	64	67	68	70	71	71	69	66	63	60	57	54	52	50	49	47	47	47	47
Dewpoint (°F)	47	46	45	44	43	42	41	40	40	40	40	41	42	43	43	44	44	43	43	43	43	42	42	42
Heat Index (°F)
Surface Wind (mph)	6	6	7	7	8	8	7	7	7	6	6	5	5	3	3	2	2	2	2	2	2	2	2	2
Wind Dir	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW	NW
Gust
Sky Cover (%)	1	1	1	1	1	2	2	2	2	3	3	3	2	2	2	2	2	2	2	2	2	2	2	2
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 (%)	96	86	71	59	51	45	39	36	33	32	32	36	42	48	53	62	69	71	77	80	86	83	83	83
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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