Point Forecast: Markham IL  41.6N 87.7W	Last Update: 5:41 pm CDT Jul 16, 2025

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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: 5pm Wed, Jul 16 20256pm Wed, Jul 16 20257pm Wed, Jul 16 20258pm Wed, Jul 16 20259pm Wed, Jul 16 202510pm Wed, Jul 16 202511pm Wed, Jul 16 202512am Thu, Jul 17 20251am Thu, Jul 17 20252am Thu, Jul 17 20253am Thu, Jul 17 20254am Thu, Jul 17 20255am Thu, Jul 17 20256am Thu, Jul 17 20257am Thu, Jul 17 20258am Thu, Jul 17 20259am Thu, Jul 17 202510am Thu, Jul 17 202511am Thu, Jul 17 202512pm Thu, Jul 17 20251pm Thu, Jul 17 20252pm Thu, Jul 17 20253pm Thu, Jul 17 20254pm Thu, Jul 17 20255pm Thu, Jul 17 20256pm Thu, Jul 17 20257pm Thu, Jul 17 20258pm Thu, Jul 17 20259pm Thu, Jul 17 202510pm Thu, Jul 17 202511pm Thu, Jul 17 202512am Fri, Jul 18 20251am Fri, Jul 18 20252am Fri, Jul 18 20253am Fri, Jul 18 20254am Fri, Jul 18 20255am Fri, Jul 18 20256am Fri, Jul 18 20257am Fri, Jul 18 20258am Fri, Jul 18 20259am Fri, Jul 18 202510am Fri, Jul 18 202511am Fri, Jul 18 202512pm Fri, Jul 18 20251pm Fri, Jul 18 20252pm Fri, Jul 18 20253pm Fri, Jul 18 20254pm Fri, Jul 18 20255pm Fri, Jul 18 20256pm Fri, Jul 18 20257pm Fri, Jul 18 20258pm Fri, Jul 18 20259pm Fri, Jul 18 202510pm Fri, Jul 18 202511pm Fri, Jul 18 202512am Sat, Jul 19 20251am Sat, Jul 19 20252am Sat, Jul 19 20253am Sat, Jul 19 20254am Sat, Jul 19 20255am Sat, Jul 19 20256am Sat, Jul 19 20257am Sat, Jul 19 20258am Sat, Jul 19 20259am Sat, Jul 19 202510am Sat, Jul 19 202511am Sat, Jul 19 202512pm Sat, Jul 19 20251pm Sat, Jul 19 20252pm Sat, Jul 19 20253pm Sat, Jul 19 20254pm Sat, Jul 19 20255pm Sat, Jul 19 20256pm Sat, Jul 19 20257pm Sat, Jul 19 20258pm Sat, Jul 19 20259pm Sat, Jul 19 202510pm Sat, Jul 19 202511pm Sat, Jul 19 202512am Sun, Jul 20 20251am Sun, Jul 20 20252am Sun, Jul 20 20253am Sun, Jul 20 20254am Sun, Jul 20 20255am Sun, Jul 20 20256am Sun, Jul 20 20257am Sun, Jul 20 20258am Sun, Jul 20 20259am Sun, Jul 20 202510am Sun, Jul 20 202511am Sun, Jul 20 202512pm Sun, Jul 20 20251pm Sun, Jul 20 20252pm Sun, Jul 20 20253pm Sun, Jul 20 20254pm Sun, Jul 20 20255pm Sun, Jul 20 20256pm Sun, Jul 20 20257pm Sun, Jul 20 20258pm Sun, Jul 20 20259pm Sun, Jul 20 202510pm Sun, Jul 20 202511pm Sun, Jul 20 202512am Mon, Jul 21 20251am Mon, Jul 21 20252am Mon, Jul 21 20253am Mon, Jul 21 20254am Mon, Jul 21 2025

Date	07/16							07/17
Hour (CDT)	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16
Temperature (°F)	73	77	80	81	78	73	73	74	74	74	74	73	71	70	71	71	73	74	75	76	76	76	75	75
Dewpoint (°F)	70	70	71	71	71	71	70	70	69	69	68	68	67	66	66	65	64	64	63	63	63	63	62	62
Heat Index (°F)		77	83	84	78														75	76	76	76	75	75
Surface Wind (mph)	15	15	15	14	13	13	11	11	8	8	7	7	7	8	8	8	8	8	8	9	10	10	11	11
Wind Dir	SW	WSW	WSW	SW	SW	WSW	WSW	WSW	W	WNW	WNW	NW	NW	NNW	NNW	NNW	N	N	N	NNE	NNE	NNE	NE	NE
Gust	22	23	23	23	21	21	21	21	13						13	13	13	13	13	14	15	16	17	18
Sky Cover (%)	37	43	54	59	62	74	67	61	56	61	67	73	77	80	84	81	79	77	76	74	74	73	73	73
Precipitation Potential (%)	23	18	14	14	14	14	12	11	9	10	10	10	10	10	7	7	8	8	8	8	6	6	6	8
Relative Humidity (%)	93	81	74	72	78	91	91	88	85	82	83	84	87	87	83	81	74	70	67	65	65	64	64	64
Rain	SChc	SChc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	SChc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date								07/18
Hour (CDT)	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16
Temperature (°F)	73	72	70	70	68	67	66	65	64	64	63	63	63	64	65	68	70	73	76	78	80	81	82	82
Dewpoint (°F)	62	61	60	60	60	59	59	59	58	58	58	58	58	59	60	60	60	61	61	61	62	62	62	63
Heat Index (°F)																			76	78	81	82	83	84
Surface Wind (mph)	11	13	11	11	10	9	8	7	7	7	6	6	6	6	5	5	5	5	6	6	6	6	7	7
Wind Dir	NE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NNE	NE	NE	ENE	ENE	E	E	E	E	E	E	E	E
Gust	20	20	20	18	16	14
Sky Cover (%)	68	63	58	59	61	63	57	51	46	45	44	43	38	34	29	29	28	28	32	35	39	37	34	32
Precipitation Potential (%)	8	8	3	3	3	3	3	3	4	4	4	4	4	4	4	4	4	4	4	4	8	8	8	8
Relative Humidity (%)	67	69	71	71	76	77	78	79	80	82	83	84	85	84	82	76	71	65	60	56	54	52	51	51
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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