St. Mary, MO Weather - Forecast & Monthly Averages

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TEMPERATURE	46
HUMIDITY	74
PRESSURE	101659.39
WIND COND.	210 5.5

Weather Quick Facts

The highest monthly average temperature in St. Mary for July is 78 degrees
The lowest monthly average temperature in St. Mary for January is 32.9 degrees
The most monthly precipitation in St. Mary occurs in August with 10.7 inches
The air quality index in St. Mary is 28% worse than the national average
The pollution index in St. Mary is 72% better than the national average

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St. Mary Average Temperature

In the event that the weather data was unavailable for this city, estimates based upon nearby cities were used.
Month	Temp. _(min)	Temp. _(max)	Temp. _(avg)	Precipitation
January	25°F	42°F	33°F	4.6"
February	27°F	45°F	35°F	2.4"
March	39°F	58°F	48°F	3.7"
April	48°F	69°F	58°F	6.6"
May	57°F	77°F	66°F	10.0"
June	66°F	86°F	76°F	8.8"
July	69°F	88°F	78°F	6.8"
August	67°F	87°F	76°F	10.7"
September	59°F	81°F	69°F	7.4"
October	48°F	70°F	58°F	9.0"
November	38°F	57°F	47°F	6.5"
December	30°F	45°F	37°F	7.7"

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St. Mary air quality index & pollution index

In the event that the air quality/pollution data was unavailable for this city, estimates based upon nearby cities were used.
Index	St. Mary	Missouri	National
Air quality index	54	97	42
Pollution index	753,473	1,630,255	2,726,193

St. Mary air quality

Measurement	Total
Days measured	365
Days with good air quality	134
Days with moderate air quality	221
Days w/ poor A.Q. for sensitive groups	8
Days with unhealthy air quality	2

Air quality details

Pollutant	Total
Arsenic	0.001%
Benzene	0.010%
Carbon Tetrachloride	0.001%
Lead	0.020%
Mercury	0.020%

Average monthly St. Mary temperature with heat index

St. Mary monthly precipitation with daily maximum

St. Mary monthly snow depth with daily maximum

St. Mary monthly wind speed information

Nearby cities with good air quality

City	Population	Air Quality Index	National Avg.
Longtown, MO	127	43	14.0%
Rockwood, IL	25	43	14.0%
Perryville, MO	8,500	54	8.0%
Lithium, MO	88	54	8.0%
Kaskaskia, IL	29	54	8.0%
St. Mary, MO	261	54	8.0%

Cities with similar population

City	Population	Air Quality Index	National Avg.
Moro, AR	261	45	10.0%
Acampo, CA	261	45	10.0%
Lineville, IA	261	39	22.0%
Shamrock Lakes, IN	261	35	30.0%
Belfry, KY	261	42	16.0%
St. Mary, MO	261	54	8.0%

Source: The St. Mary, MO weather data displayed above is derived from the NOAA (National Oceanic and Atmospheric). Air quality and pollution data is derived from the EPA (United States Environmental Protection Agency). Air quality and pollution levels measured in a particular area may not be representative of the entire county.