Point Forecast: Ashton-Sandy Spring MD  39.15N 77.01W (Elev. 449 ft)	Last Update: 10:53 am EDT Sep 11, 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: 1pm Fri, Sep 11 20262pm Fri, Sep 11 20263pm Fri, Sep 11 20264pm Fri, Sep 11 20265pm Fri, Sep 11 20266pm Fri, Sep 11 20267pm Fri, Sep 11 20268pm Fri, Sep 11 20269pm Fri, Sep 11 202610pm Fri, Sep 11 202611pm Fri, Sep 11 202612am Sat, Sep 12 20261am Sat, Sep 12 20262am Sat, Sep 12 20263am Sat, Sep 12 20264am Sat, Sep 12 20265am Sat, Sep 12 20266am Sat, Sep 12 20267am Sat, Sep 12 20268am Sat, Sep 12 20269am Sat, Sep 12 202610am Sat, Sep 12 202611am Sat, Sep 12 202612pm Sat, Sep 12 20261pm Sat, Sep 12 20262pm Sat, Sep 12 20263pm Sat, Sep 12 20264pm Sat, Sep 12 20265pm Sat, Sep 12 20266pm Sat, Sep 12 20267pm Sat, Sep 12 20268pm Sat, Sep 12 20269pm Sat, Sep 12 202610pm Sat, Sep 12 202611pm Sat, Sep 12 202612am Sun, Sep 13 20261am Sun, Sep 13 20262am Sun, Sep 13 20263am Sun, Sep 13 20264am Sun, Sep 13 20265am Sun, Sep 13 20266am Sun, Sep 13 20267am Sun, Sep 13 20268am Sun, Sep 13 20269am Sun, Sep 13 202610am Sun, Sep 13 202611am Sun, Sep 13 202612pm Sun, Sep 13 20261pm Sun, Sep 13 20262pm Sun, Sep 13 20263pm Sun, Sep 13 20264pm Sun, Sep 13 20265pm Sun, Sep 13 20266pm Sun, Sep 13 20267pm Sun, Sep 13 20268pm Sun, Sep 13 20269pm Sun, Sep 13 202610pm Sun, Sep 13 202611pm Sun, Sep 13 202612am Mon, Sep 14 20261am Mon, Sep 14 20262am Mon, Sep 14 20263am Mon, Sep 14 20264am Mon, Sep 14 20265am Mon, Sep 14 20266am Mon, Sep 14 20267am Mon, Sep 14 20268am Mon, Sep 14 20269am Mon, Sep 14 202610am Mon, Sep 14 202611am Mon, Sep 14 202612pm Mon, Sep 14 20261pm Mon, Sep 14 20262pm Mon, Sep 14 20263pm Mon, Sep 14 20264pm Mon, Sep 14 20265pm Mon, Sep 14 20266pm Mon, Sep 14 20267pm Mon, Sep 14 20268pm Mon, Sep 14 20269pm Mon, Sep 14 202610pm Mon, Sep 14 202611pm Mon, Sep 14 202612am Tue, Sep 15 20261am Tue, Sep 15 20262am Tue, Sep 15 20263am Tue, Sep 15 20264am Tue, Sep 15 20265am Tue, Sep 15 20266am Tue, Sep 15 20267am Tue, Sep 15 20268am Tue, Sep 15 20269am Tue, Sep 15 202610am Tue, Sep 15 202611am Tue, Sep 15 202612pm Tue, Sep 15 20261pm Tue, Sep 15 20262pm Tue, Sep 15 20263pm Tue, Sep 15 20264pm Tue, Sep 15 20265pm Tue, Sep 15 20266pm Tue, Sep 15 20267pm Tue, Sep 15 20268pm Tue, Sep 15 20269pm Tue, Sep 15 202610pm Tue, Sep 15 202611pm Tue, Sep 15 202612am Wed, Sep 16 2026

Date	09/11											09/12
Hour (EDT)	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12
Temperature (°F)	76	76	78	78	78	77	76	73	69	67	67	66	66	66	65	66	66	66	66	67	70	73	75	76
Dewpoint (°F)	65	64	64	64	64	65	65	65	65	64	64	64	65	65	65	65	65	65	66	66	66	67	68	69
Heat Index (°F)	76	76	78	78	78	77	76																75	76
Surface Wind (mph)	3	3	2	2	2	2	2	2	1	1	1	1	1	1	1	1	2	2	2	3	5	7	8	8
Wind Dir	NE	NE	NE	NE	E	E	E	E	E	E	E	E	E	E	E	E	E	E	E	E	E	SE	SE	SE
Gust
Sky Cover (%)	84	83	73	85	76	68	60	47	50	48	44	49	58	70	79	82	74	82	83	82	74	63	71	73
Precipitation Potential (%)	8	4	3	3	3	3	3	3	3	2	3	5	12	19	18	17	16	14	23	30	28	19	4	5
Relative Humidity (%)	69	66	62	62	62	67	69	76	87	90	90	93	97	97	100	97	97	97	100	97	87	81	79	79
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	SChc	--	SChc	Chc	Chc	SChc	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date												09/13
Hour (EDT)	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12
Temperature (°F)	78	77	78	79	78	77	76	73	71	70	70	70	70	70	70	70	69	69	69	69	72	74	77	79
Dewpoint (°F)	69	70	70	71	71	71	71	71	71	70	70	70	70	70	70	70	69	69	69	69	71	73	74	74
Heat Index (°F)	78	77	78	79	78	77	76																77	79
Surface Wind (mph)	8	8	8	7	7	6	6	5	5	3	3	2	2	1	1	1	1	1	1	2	3	5	6	6
Wind Dir	SE	SE	SE	SE	SE	SE	SE	SE	SE	SE	S	S	S	S	S	SW	SW	SW	W	W	W	NW	NW	NW
Gust
Sky Cover (%)	80	72	74	79	84	80	83	91	91	91	91	91	91	86	84	82	80	79	77	76	69	62	55	49
Precipitation Potential (%)	7	47	56	68	49	33	70	86	86	86	86	86	86	59	59	59	59	59	59	13	13	13	13	13
Relative Humidity (%)	74	79	76	77	79	82	85	93	100	100	100	100	100	100	100	100	100	100	100	100	97	97	90	85
Rain	--	Chc	Lkly	Lkly	Chc	Chc	Lkly	Ocnl	Ocnl	Ocnl	Ocnl	Ocnl	Ocnl	Lkly	Lkly	Lkly	Lkly	Lkly	Lkly	--	--	--	--	--
Thunder	--	SChc	SChc	SChc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--

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