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Point Forecast: Herndon VA  38.97N 77.38W (Elev. 354 ft)	Last Update: 10:30 pm EDT Jul 19, 2019

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Weather Elements Weather/Precipitation Fire 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)

48-Hour Period Starting: 11pm Fri, Jul 19 201912am Sat, Jul 20 20191am Sat, Jul 20 20192am Sat, Jul 20 20193am Sat, Jul 20 20194am Sat, Jul 20 20195am Sat, Jul 20 20196am Sat, Jul 20 20197am Sat, Jul 20 20198am Sat, Jul 20 20199am Sat, Jul 20 201910am Sat, Jul 20 201911am Sat, Jul 20 201912pm Sat, Jul 20 20191pm Sat, Jul 20 20192pm Sat, Jul 20 20193pm Sat, Jul 20 20194pm Sat, Jul 20 20195pm Sat, Jul 20 20196pm Sat, Jul 20 20197pm Sat, Jul 20 20198pm Sat, Jul 20 20199pm Sat, Jul 20 201910pm Sat, Jul 20 201911pm Sat, Jul 20 201912am Sun, Jul 21 20191am Sun, Jul 21 20192am Sun, Jul 21 20193am Sun, Jul 21 20194am Sun, Jul 21 20195am Sun, Jul 21 20196am Sun, Jul 21 20197am Sun, Jul 21 20198am Sun, Jul 21 20199am Sun, Jul 21 201910am Sun, Jul 21 201911am Sun, Jul 21 201912pm Sun, Jul 21 20191pm Sun, Jul 21 20192pm Sun, Jul 21 20193pm Sun, Jul 21 20194pm Sun, Jul 21 20195pm Sun, Jul 21 20196pm Sun, Jul 21 20197pm Sun, Jul 21 20198pm Sun, Jul 21 20199pm Sun, Jul 21 201910pm Sun, Jul 21 201911pm Sun, Jul 21 201912am Mon, Jul 22 20191am Mon, Jul 22 20192am Mon, Jul 22 20193am Mon, Jul 22 20194am Mon, Jul 22 20195am Mon, Jul 22 20196am Mon, Jul 22 20197am Mon, Jul 22 20198am Mon, Jul 22 20199am Mon, Jul 22 201910am Mon, Jul 22 201911am Mon, Jul 22 201912pm Mon, Jul 22 20191pm Mon, Jul 22 20192pm Mon, Jul 22 20193pm Mon, Jul 22 20194pm Mon, Jul 22 20195pm Mon, Jul 22 20196pm Mon, Jul 22 20197pm Mon, Jul 22 20198pm Mon, Jul 22 20199pm Mon, Jul 22 201910pm Mon, Jul 22 201911pm Mon, Jul 22 201912am Tue, Jul 23 20191am Tue, Jul 23 20192am Tue, Jul 23 20193am Tue, Jul 23 20194am Tue, Jul 23 20195am Tue, Jul 23 20196am Tue, Jul 23 20197am Tue, Jul 23 20198am Tue, Jul 23 20199am Tue, Jul 23 201910am Tue, Jul 23 201911am Tue, Jul 23 201912pm Tue, Jul 23 20191pm Tue, Jul 23 20192pm Tue, Jul 23 20193pm Tue, Jul 23 20194pm Tue, Jul 23 20195pm Tue, Jul 23 20196pm Tue, Jul 23 20197pm Tue, Jul 23 20198pm Tue, Jul 23 20199pm Tue, Jul 23 201910pm Tue, Jul 23 201911pm Tue, Jul 23 201912am Wed, Jul 24 20191am Wed, Jul 24 20192am Wed, Jul 24 20193am Wed, Jul 24 20194am Wed, Jul 24 20195am Wed, Jul 24 20196am Wed, Jul 24 20197am Wed, Jul 24 20198am Wed, Jul 24 20199am Wed, Jul 24 201910am Wed, Jul 24 2019

Date	07/19	07/20
Hour (EDT)	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22
Temperature (°F)	84	83	82	80	79	78	77	77	79	82	85	89	93	96	97	99	100	100	99	96	93	90	88	86
Dewpoint (°F)	72	72	72	73	73	73	73	74	74	74	74	75	76	75	74	74	73	72	72	71	70	71	71	72
Heat Index (°F)	90	88	87	84	79	78	77	77	79	88	93	99	106	108	109	111	111	110	109	104	99	96	94	92
Surface Wind (mph)	6	6	5	3	3	5	3	3	3	5	6	7	7	7	7	7	7	8	8	8	7	6	6	5
Wind Dir	W	W	W	W	W	SW	W	W	W	W	W	W	NW	W	W	W	W	W	W	W	W	W	W	SW
Gust
Sky Cover (%)	48	40	23	15	17	20	21	23	27	26	29	35	38	37	34	32	34	39	41	42	44	45	46	49
Precipitation Potential (%)	7	7	7	3	3	3	3	3	3	5	5	5	5	5	5	10	10	10	10	10	10	14	14	14
Relative Humidity (%)	67	70	72	79	82	85	87	90	85	77	70	64	58	51	48	45	42	41	42	45	47	54	57	63
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date		07/21
Hour (EDT)	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22
Temperature (°F)	84	83	82	81	80	79	79	79	82	85	87	90	93	94	96	97	98	98	98	96	93	90	87	85
Dewpoint (°F)	73	73	73	73	73	74	74	74	75	75	75	74	74	73	73	72	71	71	71	71	72	72	72	72
Heat Index (°F)	90	89	87	86	84	79	79	79	89	94	96	99	103	103	106	106	106	106	106	104	101	97	94	91
Surface Wind (mph)	5	5	3	3	3	5	5	5	5	5	6	6	7	7	6	6	6	7	7	6	6	5	5	5
Wind Dir	SW	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W	W
Gust
Sky Cover (%)	50	47	41	38	36	33	31	31	31	31	31	31	31	35	42	46	49	54	56	57	58	58	65	78
Precipitation Potential (%)	14	14	14	3	3	3	3	3	3	12	12	12	12	12	12	29	29	29	29	29	29	37	37	37
Relative Humidity (%)	70	72	74	77	79	85	85	85	79	72	68	60	54	51	48	45	42	42	42	45	51	56	61	65
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc

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