Point Forecast: St. Charles County Smartt Airport MO  38.94N 90.45W (Elev. 427 ft)	Last Update: 4:11 pm CDT Sep 13, 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 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: 4pm Sun, Sep 13 20265pm Sun, Sep 13 20266pm Sun, Sep 13 20267pm Sun, Sep 13 20268pm Sun, Sep 13 20269pm Sun, Sep 13 202610pm Sun, Sep 13 202611pm Sun, Sep 13 202612am Mon, Sep 14 20261am Mon, Sep 14 20262am Mon, Sep 14 20263am Mon, Sep 14 20264am Mon, Sep 14 20265am Mon, Sep 14 20266am Mon, Sep 14 20267am Mon, Sep 14 20268am Mon, Sep 14 20269am Mon, Sep 14 202610am Mon, Sep 14 202611am Mon, Sep 14 202612pm Mon, Sep 14 20261pm Mon, Sep 14 20262pm Mon, Sep 14 20263pm Mon, Sep 14 20264pm Mon, Sep 14 20265pm Mon, Sep 14 20266pm Mon, Sep 14 20267pm Mon, Sep 14 20268pm Mon, Sep 14 20269pm Mon, Sep 14 202610pm Mon, Sep 14 202611pm Mon, Sep 14 202612am Tue, Sep 15 20261am Tue, Sep 15 20262am Tue, Sep 15 20263am Tue, Sep 15 20264am Tue, Sep 15 20265am Tue, Sep 15 20266am Tue, Sep 15 20267am Tue, Sep 15 20268am Tue, Sep 15 20269am Tue, Sep 15 202610am Tue, Sep 15 202611am Tue, Sep 15 202612pm Tue, Sep 15 20261pm Tue, Sep 15 20262pm Tue, Sep 15 20263pm Tue, Sep 15 20264pm Tue, Sep 15 20265pm Tue, Sep 15 20266pm Tue, Sep 15 20267pm Tue, Sep 15 20268pm Tue, Sep 15 20269pm Tue, Sep 15 202610pm Tue, Sep 15 202611pm Tue, Sep 15 202612am Wed, Sep 16 20261am Wed, Sep 16 20262am Wed, Sep 16 20263am Wed, Sep 16 20264am Wed, Sep 16 20265am Wed, Sep 16 20266am Wed, Sep 16 20267am Wed, Sep 16 20268am Wed, Sep 16 20269am Wed, Sep 16 202610am Wed, Sep 16 202611am Wed, Sep 16 202612pm Wed, Sep 16 20261pm Wed, Sep 16 20262pm Wed, Sep 16 20263pm Wed, Sep 16 20264pm Wed, Sep 16 20265pm Wed, Sep 16 20266pm Wed, Sep 16 20267pm Wed, Sep 16 20268pm Wed, Sep 16 20269pm Wed, Sep 16 202610pm Wed, Sep 16 202611pm Wed, Sep 16 202612am Thu, Sep 17 20261am Thu, Sep 17 20262am Thu, Sep 17 20263am Thu, Sep 17 20264am Thu, Sep 17 20265am Thu, Sep 17 20266am Thu, Sep 17 20267am Thu, Sep 17 20268am Thu, Sep 17 20269am Thu, Sep 17 202610am Thu, Sep 17 202611am Thu, Sep 17 202612pm Thu, Sep 17 20261pm Thu, Sep 17 20262pm Thu, Sep 17 20263pm Thu, Sep 17 20264pm Thu, Sep 17 20265pm Thu, Sep 17 20266pm Thu, Sep 17 20267pm Thu, Sep 17 20268pm Thu, Sep 17 20269pm Thu, Sep 17 202610pm Thu, Sep 17 202611pm Thu, Sep 17 202612am Fri, Sep 18 20261am Fri, Sep 18 20262am Fri, Sep 18 20263am Fri, Sep 18 2026

Date	09/13								09/14
Hour (CDT)	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15
Temperature (°F)	88	87	84	80	76	72	71	70	69	68	66	66	65	64	63	63	65	68	71	74	77	80	82	83
Dewpoint (°F)	58	58	58	57	57	56	55	55	55	55	54	54	54	53	53	52	54	54	53	55	56	57	59	60
Heat Index (°F)	87	86	84	80	76																77	80	82	83
Surface Wind (mph)	10	10	10	8	9	8	8	8	7	8	8	8	9	9	10	10	11	11	11	13	13	13	13	13
Wind Dir	N	N	N	NE	NE	NE	NE	NE	NE	NE	NE	NE	E	E	E	E	E	E	E	SE	SE	SE	SE	SE
Gust																							20	20
Sky Cover (%)	9	20	32	43	50	32	55	63	68	75	70	64	60	44	43	50	41	35	50	71	66	36	41	33
Precipitation Potential (%)	4	4	5	7	9	9	9	10	11	9	8	5	3	3	3	6	8	11	16	21	17	13	10	6
Relative Humidity (%)	36	38	41	45	52	57	57	59	61	63	65	65	68	67	70	67	68	61	53	51	48	45	46	46
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	SChc	SChc	SChc	--	--	--
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--
Date									09/15
Hour (CDT)	16	17	18	19	20	21	22	23	00	01	02	03	04	05	06	07	08	09	10	11	12	13	14	15
Temperature (°F)	85	85	84	83	79	77	76	75	74	74	72	72	72	71	71	71	75	80	86	90	93	96	96	97
Dewpoint (°F)	61	63	65	65	67	68	68	68	69	69	69	69	69	69	69	69	70	70	70	70	70	70	70	69
Heat Index (°F)	85	86	86	85	79	77	76	75									75	83	91	96	99	103	103	103
Surface Wind (mph)	13	13	13	11	13	13	13	11	10	10	10	10	9	9	9	9	9	9	10	11	11	11	10	8
Wind Dir	SE	SE	SE	SE	SE	SE	SE	SE	SE	SE	S	S	S	S	S	S	S	S	S	SW	SW	SW	SW	SW
Gust						20
Sky Cover (%)	23	23	23	9	2	1	3	2	3	1	4	8	18	20	13	11	2	9	15	15	15	15	19	24
Precipitation Potential (%)	3	2	0	0	0	0	0	0	0	0	0	0	0	0	3	6	6	6	6	6	6	38	38	38
Relative Humidity (%)	45	48	53	55	67	74	76	79	84	84	90	90	90	93	93	93	84	72	59	52	47	43	43	40
Rain	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	Chc	Chc	Chc
Thunder	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	--	Chc	Chc	Chc

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