Point Forecast: Markham IL  41.6N 87.7W	Last Update: 12:06 pm CDT Aug 11, 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: 12pm Tue, Aug 11 20261pm Tue, Aug 11 20262pm Tue, Aug 11 20263pm Tue, Aug 11 20264pm Tue, Aug 11 20265pm Tue, Aug 11 20266pm Tue, Aug 11 20267pm Tue, Aug 11 20268pm Tue, Aug 11 20269pm Tue, Aug 11 202610pm Tue, Aug 11 202611pm Tue, Aug 11 202612am Wed, Aug 12 20261am Wed, Aug 12 20262am Wed, Aug 12 20263am Wed, Aug 12 20264am Wed, Aug 12 20265am Wed, Aug 12 20266am Wed, Aug 12 20267am Wed, Aug 12 20268am Wed, Aug 12 20269am Wed, Aug 12 202610am Wed, Aug 12 202611am Wed, Aug 12 202612pm Wed, Aug 12 20261pm Wed, Aug 12 20262pm Wed, Aug 12 20263pm Wed, Aug 12 20264pm Wed, Aug 12 20265pm Wed, Aug 12 20266pm Wed, Aug 12 20267pm Wed, Aug 12 20268pm Wed, Aug 12 20269pm Wed, Aug 12 202610pm Wed, Aug 12 202611pm Wed, Aug 12 202612am Thu, Aug 13 20261am Thu, Aug 13 20262am Thu, Aug 13 20263am Thu, Aug 13 20264am Thu, Aug 13 20265am Thu, Aug 13 20266am Thu, Aug 13 20267am Thu, Aug 13 20268am Thu, Aug 13 20269am Thu, Aug 13 202610am Thu, Aug 13 202611am Thu, Aug 13 202612pm Thu, Aug 13 20261pm Thu, Aug 13 20262pm Thu, Aug 13 20263pm Thu, Aug 13 20264pm Thu, Aug 13 20265pm Thu, Aug 13 20266pm Thu, Aug 13 20267pm Thu, Aug 13 20268pm Thu, Aug 13 20269pm Thu, Aug 13 202610pm Thu, Aug 13 202611pm Thu, Aug 13 202612am Fri, Aug 14 20261am Fri, Aug 14 20262am Fri, Aug 14 20263am Fri, Aug 14 20264am Fri, Aug 14 20265am Fri, Aug 14 20266am Fri, Aug 14 20267am Fri, Aug 14 20268am Fri, Aug 14 20269am Fri, Aug 14 202610am Fri, Aug 14 202611am Fri, Aug 14 202612pm Fri, Aug 14 20261pm Fri, Aug 14 20262pm Fri, Aug 14 20263pm Fri, Aug 14 20264pm Fri, Aug 14 20265pm Fri, Aug 14 20266pm Fri, Aug 14 20267pm Fri, Aug 14 20268pm Fri, Aug 14 20269pm Fri, Aug 14 202610pm Fri, Aug 14 202611pm Fri, Aug 14 202612am Sat, Aug 15 20261am Sat, Aug 15 20262am Sat, Aug 15 20263am Sat, Aug 15 20264am Sat, Aug 15 20265am Sat, Aug 15 20266am Sat, Aug 15 20267am Sat, Aug 15 20268am Sat, Aug 15 20269am Sat, Aug 15 202610am Sat, Aug 15 202611am Sat, Aug 15 202612pm Sat, Aug 15 20261pm Sat, Aug 15 20262pm Sat, Aug 15 20263pm Sat, Aug 15 20264pm Sat, Aug 15 20265pm Sat, Aug 15 20266pm Sat, Aug 15 20267pm Sat, Aug 15 20268pm Sat, Aug 15 20269pm Sat, Aug 15 202610pm Sat, Aug 15 202611pm Sat, Aug 15 2026

Date	08/11												08/12
Hour (CDT)	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11
Temperature (°F)	78	79	79	79	81	79	79	79	76	75	74	73	72	72	72	71	70	70	69	70	72	74	76	78
Dewpoint (°F)	73	72	72	72	72	72	72	72	72	72	71	71	70	70	70	70	70	70	69	70	71	72	72	73
Heat Index (°F)	78	82	82	79	85	83	83	79	76	75													76	78
Surface Wind (mph)	7	7	6	6	6	6	5	3	3	3	3	3	2	3	2	3	3	3	2	2	2	3	3	3
Wind Dir	SSW	S	SSW	S	S	E	S	SSE	SSE	E	ESE	SE	SSE	SSE	SSE	E	SE	SSE	ESE	SSE	SSE	SSE	SE	WNW
Gust			11	11
Sky Cover (%)	77	81	80	82	90	74	53	64	75	64	62	55	55	61	67	70	68	70	64	75	83	83	77	58
Precipitation Potential (%)	93	85	72	57	49	51	42	40	37	46	47	35	33	53	54	48	28	23	13	17	36	28	43	51
Relative Humidity (%)	84	80	79	80	75	78	79	81	87	90	91	93	93	94	96	99	99	100	100	98	95	93	87	85
Rain	Ocnl	Ocnl	Lkly	Lkly	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	SChc	--	SChc	Chc	Chc	Chc	Chc
Thunder	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	Chc	SChc	SChc	SChc	Chc	Chc	Chc	SChc	SChc	--	SChc	Chc	Chc	SChc	SChc
Date													08/13
Hour (CDT)	12	13	14	15	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11
Temperature (°F)	79	79	80	81	79	79	79	77	76	75	74	73	72	72	70	70	70	69	69	70	72	74	75	76
Dewpoint (°F)	72	72	72	72	72	72	72	72	72	71	71	70	70	70	70	70	70	69	69	70	70	71	72	72
Heat Index (°F)	79	83	83	85	79	82	79	77	76	75													75	76
Surface Wind (mph)	5	5	5	5	5	5	5	5	3	3	3	3	2	2	2	3	2	2	2	2	3	5	5	5
Wind Dir	SSE	SSW	SE	ESE	WSW	NE	SSE	S	NNE	E	E	E	ENE	ENE	E	E	E	E	E	ESE	ESE	ESE	ESE	ESE
Gust
Sky Cover (%)	61	66	66	60	68	67	57	47	51	57	49	54	59	64	77	85	68	84	81	62	73	73	73	77
Precipitation Potential (%)	45	46	28	45	47	13	14	23	24	7	1	1	2	20	8	42	49	41	48	55	55	55	55	55
Relative Humidity (%)	81	79	78	75	79	77	80	84	86	89	91	92	93	94	99	99	99	100	99	98	95	92	89	87
Rain	Chc	Chc	Chc	Chc	Chc	--	--	SChc	SChc	--	--	--	--	SChc	--	Chc	Chc	Chc	Chc	Lkly	Lkly	Lkly	Lkly	Lkly
Thunder	SChc	SChc	SChc	SChc	SChc	--	--	SChc	SChc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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