Point Forecast: Chicago/Romeoville, Lewis University Airport IL  41.61N 88.1W	Last Update: 8:41 pm CDT Jul 19, 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: 11pm Sun, Jul 19 202612am Mon, Jul 20 20261am Mon, Jul 20 20262am Mon, Jul 20 20263am Mon, Jul 20 20264am Mon, Jul 20 20265am Mon, Jul 20 20266am Mon, Jul 20 20267am Mon, Jul 20 20268am Mon, Jul 20 20269am Mon, Jul 20 202610am Mon, Jul 20 202611am Mon, Jul 20 202612pm Mon, Jul 20 20261pm Mon, Jul 20 20262pm Mon, Jul 20 20263pm Mon, Jul 20 20264pm Mon, Jul 20 20265pm Mon, Jul 20 20266pm Mon, Jul 20 20267pm Mon, Jul 20 20268pm Mon, Jul 20 20269pm Mon, Jul 20 202610pm Mon, Jul 20 202611pm Mon, Jul 20 202612am Tue, Jul 21 20261am Tue, Jul 21 20262am Tue, Jul 21 20263am Tue, Jul 21 20264am Tue, Jul 21 20265am Tue, Jul 21 20266am Tue, Jul 21 20267am Tue, Jul 21 20268am Tue, Jul 21 20269am Tue, Jul 21 202610am Tue, Jul 21 202611am Tue, Jul 21 202612pm Tue, Jul 21 20261pm Tue, Jul 21 20262pm Tue, Jul 21 20263pm Tue, Jul 21 20264pm Tue, Jul 21 20265pm Tue, Jul 21 20266pm Tue, Jul 21 20267pm Tue, Jul 21 20268pm Tue, Jul 21 20269pm Tue, Jul 21 202610pm Tue, Jul 21 202611pm Tue, Jul 21 202612am Wed, Jul 22 20261am Wed, Jul 22 20262am Wed, Jul 22 20263am Wed, Jul 22 20264am Wed, Jul 22 20265am Wed, Jul 22 20266am Wed, Jul 22 20267am Wed, Jul 22 20268am Wed, Jul 22 20269am Wed, Jul 22 202610am Wed, Jul 22 202611am Wed, Jul 22 202612pm Wed, Jul 22 20261pm Wed, Jul 22 20262pm Wed, Jul 22 20263pm Wed, Jul 22 20264pm Wed, Jul 22 20265pm Wed, Jul 22 20266pm Wed, Jul 22 20267pm Wed, Jul 22 20268pm Wed, Jul 22 20269pm Wed, Jul 22 202610pm Wed, Jul 22 202611pm Wed, Jul 22 202612am Thu, Jul 23 20261am Thu, Jul 23 20262am Thu, Jul 23 20263am Thu, Jul 23 20264am Thu, Jul 23 20265am Thu, Jul 23 20266am Thu, Jul 23 20267am Thu, Jul 23 20268am Thu, Jul 23 20269am Thu, Jul 23 202610am Thu, Jul 23 202611am Thu, Jul 23 202612pm Thu, Jul 23 20261pm Thu, Jul 23 20262pm Thu, Jul 23 20263pm Thu, Jul 23 20264pm Thu, Jul 23 20265pm Thu, Jul 23 20266pm Thu, Jul 23 20267pm Thu, Jul 23 20268pm Thu, Jul 23 20269pm Thu, Jul 23 202610pm Thu, Jul 23 202611pm Thu, Jul 23 202612am Fri, Jul 24 20261am Fri, Jul 24 20262am Fri, Jul 24 20263am Fri, Jul 24 20264am Fri, Jul 24 20265am Fri, Jul 24 20266am Fri, Jul 24 20267am Fri, Jul 24 20268am Fri, Jul 24 20269am Fri, Jul 24 202610am Fri, Jul 24 2026

Date	07/19	07/20
Hour (CDT)	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22
Temperature (°F)	68	66	66	65	64	64	63	64	66	71	74	78	80	82	83	84	85	86	85	85	84	82	80	76
Dewpoint (°F)	58	59	59	60	60	60	60	60	61	62	63	63	63	63	63	63	64	64	66	66	68	68	69	69
Heat Index (°F)												78	82	83	84	86	86	87	87	88	87	85	83	76
Surface Wind (mph)	3	2	1	1	1	1	1	1	3	5	6	7	7	8	9	11	13	14	14	14	14	13	13	13
Wind Dir	E	E	E	ESE	SE	SSE	SSE	S	S	S	SSW	SSW	SSW	SSW	SSW	SSW	SW	SW	SW	SW	SSW	SSW	SSW	SSW
Gust														13	15	17	21	23	23	23	22	22	21	21
Sky Cover (%)	40	40	40	40	40	40	40	40	40	40	40	43	46	55	42	42	74	71	37	55	51	45	47	64
Precipitation Potential (%)	0	0	0	0	0	0	0	0	0	0	0	1	1	1	3	3	3	7	7	7	21	21	21	43
Relative Humidity (%)	71	77	81	83	87	89	89	89	83	74	67	60	56	53	51	49	49	49	52	54	59	64	70	79
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	Chc
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	Chc
Date		07/21
Hour (CDT)	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15	16	17	18	19	20	21	22
Temperature (°F)	76	75	75	74	74	73	73	73	73	76	78	80	82	83	84	85	85	84	84	82	80	78	76	73
Dewpoint (°F)	70	70	71	71	70	70	70	70	70	70	71	70	70	69	68	68	67	67	66	65	64	64	64	64
Heat Index (°F)	76	75	75							76	78	83	85	87	87	88	88	87	86	84	82	78	76
Surface Wind (mph)	13	13	13	11	11	11	11	11	11	11	13	14	15	16	16	17	17	17	17	16	16	14	13	13
Wind Dir	SW	SW	SW	SW	WSW	WSW	WSW	WSW	W	W	W	WNW	WNW	WNW	WNW	WNW	NW	NW	NW	NNW	NNW	NNW	N	N
Gust	21	21	21	20	20	20	18	17	17	18	20	22	23	24	25	26	28	28	25	25	22	20	18
Sky Cover (%)	69	72	49	65	82	71	59	49	44	44	34	23	23	23	23	24	25	26	25	24	23	25	26	28
Precipitation Potential (%)	43	43	73	73	73	52	52	52	9	9	9	5	5	5	4	4	4	4	4	4	10	10	10	10
Relative Humidity (%)	82	85	87	88	89	91	91	91	89	84	78	73	67	62	59	56	56	56	56	57	59	63	68	73
Rain	Chc	Chc	Lkly	Lkly	Lkly	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Thunder	Chc	Chc	Lkly	Lkly	Lkly	Chc	Chc	Chc	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--

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