Point Forecast: Markham IL  41.6N 87.7W	Last Update: 8:56 pm CDT Sep 5, 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: 9pm 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 202610pm Tue, Sep 8 202611pm Tue, Sep 8 202612am Wed, Sep 9 20261am Wed, Sep 9 20262am Wed, Sep 9 20263am Wed, Sep 9 20264am Wed, Sep 9 20265am Wed, Sep 9 20266am Wed, Sep 9 20267am Wed, Sep 9 20268am Wed, Sep 9 20269am Wed, Sep 9 202610am Wed, Sep 9 202611am Wed, Sep 9 202612pm Wed, Sep 9 20261pm Wed, Sep 9 20262pm Wed, Sep 9 20263pm Wed, Sep 9 20264pm Wed, Sep 9 20265pm Wed, Sep 9 20266pm Wed, Sep 9 20267pm Wed, Sep 9 20268pm Wed, Sep 9 20269pm Wed, Sep 9 202610pm Wed, Sep 9 202611pm Wed, Sep 9 202612am Thu, Sep 10 20261am Thu, Sep 10 20262am Thu, Sep 10 20263am Thu, Sep 10 20264am Thu, Sep 10 20265am Thu, Sep 10 20266am Thu, Sep 10 20267am Thu, Sep 10 20268am Thu, Sep 10 2026

Date	09/05			09/06
Hour (CDT)	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20
Temperature (°F)	74	74	73	73	72	72	71	70	69	68	68	70	72	75	76	77	78	78	77	76	75	74	73	72
Dewpoint (°F)	68	68	68	68	67	67	65	65	64	64	63	62	60	59	57	56	55	55	55	57	58	59	59	60
Heat Index (°F)														75	76	77	78	78	77	76	75
Surface Wind (mph)	9	8	8	7	6	6	5	5	5	5	5	6	7	8	8	9	9	10	10	10	9	9	8	7
Wind Dir	NNE	NE	NE	ENE	ENE	ENE	ENE	ENE	ENE	ENE	ENE	E	ENE	ENE	ENE	ENE	ENE	ENE	ENE	NE	ENE	NE	NE	NE
Gust	20	18	17	15	13	11	10								13	14	14	15	15		14
Sky Cover (%)	79	72	62	58	52	47	39	30	20	13	9	10	12	13	15	16	18	19	25	24	23	27	24	23
Precipitation Potential (%)	1	0	0	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Relative Humidity (%)	82	83	84	84	85	85	84	85	85	86	85	76	67	57	53	48	45	45	46	50	55	59	63	66
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date				09/07
Hour (CDT)	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20
Temperature (°F)	71	70	69	68	67	67	65	64	63	62	63	66	69	72	75	77	79	80	80	80	80	78	77	75
Dewpoint (°F)	61	61	61	61	61	60	60	60	59	59	58	59	59	59	59	58	58	59	59	59	60	60	60	60
Heat Index (°F)															75	77	79	81	81	81	81	78	77	75
Surface Wind (mph)	6	5	5	3	3	3	3	3	3	3	3	5	6	6	7	7	7	7	7	7	7	7	7	7
Wind Dir	ENE	ENE	ENE	E	E	E	E	ESE	ESE	ESE	ESE	E	ESE	ESE	ESE	E	E	E	E	E	E	E	E	E
Gust
Sky Cover (%)	29	34	42	42	33	27	30	32	22	17	16	17	16	16	18	21	24	25	26	27	29	31	33	32
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 (%)	70	73	76	78	79	80	84	85	87	90	85	79	71	63	57	53	50	48	48	48	51	53	56	60
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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