Point Forecast: Mc Lean VA  38.95N 77.19W (Elev. 253 ft)	Last Update: 4:53 am EDT May 13, 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: 5am Wed, May 13 20266am Wed, May 13 20267am Wed, May 13 20268am Wed, May 13 20269am Wed, May 13 202610am Wed, May 13 202611am Wed, May 13 202612pm Wed, May 13 20261pm Wed, May 13 20262pm Wed, May 13 20263pm Wed, May 13 20264pm Wed, May 13 20265pm Wed, May 13 20266pm Wed, May 13 20267pm Wed, May 13 20268pm Wed, May 13 20269pm Wed, May 13 202610pm Wed, May 13 202611pm Wed, May 13 202612am Thu, May 14 20261am Thu, May 14 20262am Thu, May 14 20263am Thu, May 14 20264am Thu, May 14 20265am Thu, May 14 20266am Thu, May 14 20267am Thu, May 14 20268am Thu, May 14 20269am Thu, May 14 202610am Thu, May 14 202611am Thu, May 14 202612pm Thu, May 14 20261pm Thu, May 14 20262pm Thu, May 14 20263pm Thu, May 14 20264pm Thu, May 14 20265pm Thu, May 14 20266pm Thu, May 14 20267pm Thu, May 14 20268pm Thu, May 14 20269pm Thu, May 14 202610pm Thu, May 14 202611pm Thu, May 14 202612am Fri, May 15 20261am Fri, May 15 20262am Fri, May 15 20263am Fri, May 15 20264am Fri, May 15 20265am Fri, May 15 20266am Fri, May 15 20267am Fri, May 15 20268am Fri, May 15 20269am Fri, May 15 202610am Fri, May 15 202611am Fri, May 15 202612pm Fri, May 15 20261pm Fri, May 15 20262pm Fri, May 15 20263pm Fri, May 15 20264pm Fri, May 15 20265pm Fri, May 15 20266pm Fri, May 15 20267pm Fri, May 15 20268pm Fri, May 15 20269pm Fri, May 15 202610pm Fri, May 15 202611pm Fri, May 15 202612am Sat, May 16 20261am Sat, May 16 20262am Sat, May 16 20263am Sat, May 16 20264am Sat, May 16 20265am Sat, May 16 20266am Sat, May 16 20267am Sat, May 16 20268am Sat, May 16 20269am Sat, May 16 202610am Sat, May 16 202611am Sat, May 16 202612pm Sat, May 16 20261pm Sat, May 16 20262pm Sat, May 16 20263pm Sat, May 16 20264pm Sat, May 16 20265pm Sat, May 16 20266pm 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 2026

Date	05/13																			05/14
Hour (EDT)	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04
Temperature (°F)	59	57	57	60	64	67	70	72	74	75	76	73	72	71	69	67	64	63	61	60	58	57	56	55
Dewpoint (°F)	41	41	42	43	44	45	46	47	47	47	49	50	52	53	54	55	55	56	57	56	55	54	53	52
Heat Index (°F)										75	76
Surface Wind (mph)	13	13	13	14	15	15	15	14	14	14	13	11	11	10	9	9	7	6	5	5	3	3	5	7
Wind Dir	S	S	S	S	SW	SW	S	S	S	S	SW	SW	W	SW	S	SW	SW	SW	SW	SW	W	W	NW	NW
Gust	21	21	23	26	28	26	26	25	25	24	23	22	22	20
Sky Cover (%)	10	15	36	42	9	30	44	51	64	55	54	66	70	78	66	83	89	96	82	72	63	40	38	25
Precipitation Potential (%)	0	1	1	0	0	0	1	3	4	11	22	41	53	40	38	74	82	93	72	53	35	16	12	7
Relative Humidity (%)	51	55	57	53	48	45	42	41	38	37	39	44	49	53	59	65	73	78	87	87	90	90	90	90
Rain	--	--	--	--	--	--	--	--	--	--	SChc	Chc	Chc	Chc	Chc	Lkly	Ocnl	Ocnl	Lkly	Chc	Chc	SChc	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	Chc	Chc	Chc	--	--	--	--	--	--
Date																				05/15
Hour (EDT)	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04
Temperature (°F)	54	54	53	55	56	59	61	61	62	63	64	64	64	65	63	61	58	56	55	54	53	52	51	51
Dewpoint (°F)	50	49	48	48	49	49	48	48	47	46	46	46	45	45	45	45	44	44	44	44	44	44	44	44
Heat Index (°F)
Surface Wind (mph)	8	9	9	10	11	13	13	14	14	14	14	14	14	14	13	11	11	11	10	10	10	10	10	10
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				18	20	21	21	22	22	22	23	23	23	22	21	20	18				18	20	20	20
Sky Cover (%)	27	26	23	19	11	14	17	41	54	56	52	62	56	52	59	48	33	30	27	27	27	27	28	29
Precipitation Potential (%)	5	2	1	0	2	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1
Relative Humidity (%)	86	83	83	77	77	69	62	62	58	54	52	52	50	48	52	56	59	64	66	69	71	74	77	77
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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