TODAY MAY29
TEMPERATURE69
HUMIDITY45
PRESSURE30.13
WIND COND.320 15
  • 7154Sat
  • 7060Sun
  • 8269Mon30%
  • 9171Tue
  • 8967Wed30%
daynightWeather update from Des Moines, Des Moines International Airport at
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St. Marys Average Temperature

In the event that the weather data was unavailable for this city, estimates based upon nearby cities were used.
MonthTemp. (min)Temp. (max)Temp. (avg)Precipitation
January14°F35°F23°F0.9"
February17°F39°F26°F1.2"
March30°F54°F41°F2.2"
April41°F67°F53°F4.9"
May51°F76°F63°F4.9"
June62°F86°F74°F6.5"
July66°F89°F77°F4.2"
August64°F87°F75°F5.1"
September56°F81°F68°F3.7"
October43°F68°F55°F3.2"
November31°F54°F42°F1.8"
December18°F38°F27°F2.1"

Did you know?

  • The highest monthly average temperature in St. Marys for July is 77 degrees.
  • The lowest monthly average temperature in St. Marys for January is 23 degrees.
  • The most monthly precipitation in St. Marys occurs in June with 6.5 inches.
  • The air quality index in St. Marys is 18% better than the national average.
  • The pollution index in St. Marys is 93% better than the national average.

Compare St. Marys, IA Weather To Other Cities

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      St. Marys 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.
      IndexSt. MarysIowaNational
      Air quality index413950
      Pollution index376,1481,643,8365,066,862

      St. Marys air quality information

      MeasurementTotal
      Days measured365
      Days with good air quality267
      Days with moderate air quality98
      Days w/ poor A.Q. for sensitive groups
      Days with unhealthy air quality

      St. Marys air quality information

      PollutantTotal
      Arsenic0.000%
      Benzene0.010%
      Carbon Tetrachloride0.001%
      Lead0.001%
      Mercury0.000%

      Average monthly St. Marys temperature with heat index

      St. Marys monthly precipitation with daily maximum

      St. Marys monthly snow depth with daily maximum

      St. Marys monthly wind speed information

      Nearby cities with good air quality

      City, StatePopulationAir Quality IndexNational Avg.
      Carlisle, IA4,0314118%
      Martensdale, IA4524118%
      St. Charles, IA7654118%
      Cumming, IA4154118%
      New Virginia, IA5534118%
      St. Marys, IA2104118%

      Cities with similar population

      City, StatePopulationAir Quality IndexNational Avg.
      Edna, CA2105612%
      Detroit, AL2103530%
      Lowrys, SC2103628%
      Wortham, MO2106020%
      Cable, WI2103726%
      St. Marys, IA2104118%
      Source: The St. Marys, IA 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.