Daylight through the yearLongest day (Jun 21): 15 h 1 min5:33 am – 8:33 pmShortest day (Dec 21): 9 h 20 min7:19 am – 4:39 pm
Sun todaySunrise –Sunset –
Natural hazardsOverall risk Relatively ModerateDelaware County, PA, compared with all US countiesHigher-risk hazardsWinter weather Very HighStrong wind Relatively HighHeat wave Relatively HighLightning Relatively HighSource: FEMA National Risk Index (county level)
Air quality65% of days had good air in 2025238 of 365 days measured124 moderate, 2 unhealthy for sensitive groups, 1 unhealthy daysMedian index 44, worst day 153main pollutant: fine particles (PM2.5)Source: US EPA Air Quality Index, Delaware County monitors, PA
Drinking waterChester Water Authorityserves 140,437 people from surface waterNo health-based violations since 2021Source: US EPA Safe Drinking Water Information System, largest system in the county
