Point Forecast: Arlington Heights IL  42.09N 87.98W	Last Update: 9:46 am CDT Sep 4, 2026

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Weather Elements Fire Weather Probabilistic Forecasts (Experimental) Description | Survey 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 20ft Wind  ktmphkm/hm/s Vent Rate (x1000 mph-ft) Quantitative Precipitation  3-hr6-hr12-hr24-hr   info     0.100.250.501.00 Snowfall  3-hr6-hr12-hr24-hr   info     0.1in1in3in6in12in

48-Hour Period Starting: 10am Fri, Sep 4 202611am 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 2026

Date	09/04														09/05
Hour (CDT)	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09
Temperature (°F)	80	82	83	85	89	92	92	91	89	86	85	84	82	80	79	78	78	77	76	75	75	74	76	78
Dewpoint (°F)	72	72	72	72	71	72	73	73	73	74	73	73	73	72	72	72	72	72	72	71	71	72	73	74
Heat Index (°F)	83	87	89	91	96	100	101	100	97	94	92	90	88	85	83	78	78	77	76	75	75		76	78
Surface Wind (mph)	11	11	11	10	9	8	8	8	9	6	5	3	5	5	5	5	5	5	5	5	5	5	5	5
Wind Dir	NE	NE	NE	E	SSE	S	SSW	WSW	WSW	WSW	W	W	WSW	W	W	W	W	WNW	WNW	NW	NW	NNW	NNW	NNE
Gust	18	18	18	15	14	13		13	14
Sky Cover (%)	47	39	36	18	19	12	25	32	25	34	43	38	57	71	58	51	41	46	35	24	39	50	37	46
Precipitation Potential (%)	24	15	7	2	1	1	3	4	4	8	13	15	19	23	25	27	27	27	18	18	18	3	3	3
Relative Humidity (%)	79	74	69	64	56	52	53	56	60	66	69	71	72	77	79	82	83	84	86	87	89	92	90	89
Rain	SChc	SChc	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	Chc	Chc	Chc	Chc	SChc	SChc	SChc	--	--	--
Thunder	SChc	SChc	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	Chc	Chc	Chc	Chc	SChc	SChc	SChc	--	--	--
Date															09/06
Hour (CDT)	10	11	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09
Temperature (°F)	80	82	83	84	84	83	82	80	78	75	74	73	72	71	70	70	70	70	69	68	67	68	70	73
Dewpoint (°F)	75	75	75	74	73	73	72	72	71	70	70	70	70	69	69	69	69	68	68	67	67	67	67	68
Heat Index (°F)	84	88	90	91	91	89	87	84	78	75
Surface Wind (mph)	5	6	7	7	8	8	9	9	9	9	9	8	7	6	6	5	5	5	5	3	3	3	5	5
Wind Dir	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NE	NNE	NNE	NE	NE	NE	NE	NE	ENE	ENE	ENE	ENE	E	E	E	E
Gust					13	14	14	14	15	15	14	14	13	11
Sky Cover (%)	49	55	61	51	41	33	45	54	70	67	61	48	35	36	36	37	37	38	38	34	30	26	28	29
Precipitation Potential (%)	2	2	2	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	1	1	1
Relative Humidity (%)	86	81	76	72	70	71	72	74	80	83	86	89	93	95	96	95	95	95	96	99	100	98	92	83
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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