Daylight through the yearLongest day (Jun 21): 14 h 49 min5:40 am – 8:28 pmShortest day (Dec 21): 9 h 31 min7:15 am – 4:46 pm
Sun todaySunrise –Sunset –
People48 residentsin the ZIP code areaMedian age 62.831 households100% of homes owner-occupiedSource: US Census Bureau, American Community Survey 2020-2024
ClimateWarmest month July: highs 86°F, lows 67°FColdest month January: highs 40°F, lows 21°F45 in of rain a year, on about 73 dayswettest month May12 in of snow a year, on about 9 days23 days above 90°F, 103 nights below freezing in a typical yearSource: NOAA 1991-2020 Climate Normals, Potosi 4 Sw station, 14 mi away
Parks and public landsWashington State Parkstate park · 2.5 mi · 1,784 acresMo Dnr (Washington State Park Access)state park · 3.4 miWashington State Park Hardwoods Natural Areastate conservation land · 3.4 mi · 63 acresKingston Accessstate recreation area · 4.7 mi · 56 acresSaint Francois State Parkstate park · 7.6 mi · 2,530 acresMerrill Horse Accessstate recreation area · 8.9 mi · 80 acresSource: USGS Protected Areas Database (PAD-US)
Earthquakes9 of magnitude 3 or more within 50 miles since 19701 of magnitude 4+, 0 of magnitude 5+Largest: magnitude 4.2 on 11 Dec 197623 mi away, near Sullivan, MissouriMost recent: magnitude 3.9 on 7 Jun 201114 mi awaySource: USGS Earthquake Catalog
Natural hazardsOverall risk Relatively LowWashington County, MO, compared with all US countiesHighest-rated hazardsHeat wave Relatively ModerateCold wave Relatively ModerateSource: FEMA National Risk Index (county level)
Air quality73% of days had good air in 2025268 of 365 days measured93 moderate, 4 unhealthy for sensitive groups daysMedian index 42, worst day 150main pollutant: fine particles (PM2.5)Source: US EPA Air Quality Index, nearest monitors: Jefferson County, MO, 17 mi away
Internet at home100% of households have a broadband subscription65% have cable, fibre or DSL0% rely on a mobile data plan alone0% have no internet at homeSource: US Census Bureau, American Community Survey 2020-2024
Drinking waterPotosi PWSserves 2,527 people from ground waterNo health-based violations since 20213 monitoring or reporting violations since 2021Source: US EPA Safe Drinking Water Information System, largest system in the county
Elevation791 ft241 m above sea levelSource: USGS 3D Elevation Program
Local servicesHospitalWashington County Memorial Hospital9.8 miPost officeTiff Post Office1.3 miTown hallDe Soto City Hall9.1 miPoliceTerre Du Lac Police Department8.2 miFire stationPotosi Fire Protection District House 33.6 miSource: USGS National Structures Dataset
Getting aroundAirportSt. Louis Lambert International Airport STL52 miInterstateI-5518 miUS highwayUS 677.8 miAmtrakArcadia, MO ACD31 miSources: OurAirports; US Census Bureau TIGER roads; Bureau of Transportation Statistics NTAD
Distances in these cards are measured from the centre of the 63674 ZIP area.
