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Weather on April 21 at Gateway Arch

Gateway Arch National Park

MOMidwest450 ft elevation
Avg High70°F
Avg Low47°F
Warmest198575°F
Coldest202142°F

Based on 56 years of data from St. Louis, MO

Planning Your Visit

April 21st in Gateway Arch National Park (via St. Louis, MO) typically brings pleasant spring weather, with average highs around 70°F and lows near 47°F. Over 56 years of records, the warmest April 21st was in 1985 (75°F average), while the coldest was 2021 (42°F) — a 33°F range across recorded history. Rain or other precipitation has occurred on about 43% of April 21st dates historically, with the wettest April 21st recording 1.3" of rain. The last decade has been 3.9°F cooler on this date compared to 20-30 years ago.

The last decade has been 3.9°F cooler on this date compared to 20-30 years ago.

Planning for April 21st in Gateway Arch? Great weather for outdoor activities. Consider bringing rain gear or an umbrella.

Year by Year History

YearHighLowPrecipSnow
202683°F49°F0"0"
202568°F50°F0"0"
202461°F37°F0"0"
202367°F48°F0"0"
202276°F53°F0.03"0"
202152°F31°F0"0"
202066°F40°F0"0"
201980°F38°F0"0"
201869°F36°F0"0"
201783°F49°F0.03"0"
201669°F58°F0.79"0"
201559°F45°F0"0"
201481°F63°F0.1"0"
201356°F42°F0"0"
201257°F42°F0.15"--
201156°F41°F0"0"
201069°F41°F0"0"
200965°F41°F0"0"
200871°F50°F0"0"
200770°F44°F0"0"
200676°F52°F0"0"
200582°F58°F0.61"0"
200481°F56°F0.38"0"
200366°F51°F0"0"
200260°F51°F0.33"0"
200172°F64°F0.05"0"
200075°F42°F0"0"
199972°F53°F1.04"0"
199869°F48°F0"0"
199760°F49°F1.14"0"
199672°F42°F0"0"
199567°F48°F0"0"
199468°F50°F0.28"0"
199357°F37°F0.1"0"
199269°F42°F0.03"0"
199158°F36°F0"0"
199073°F45°F0.94"0"
198980°F45°F0"0"
198874°F45°F0"0"
198786°F54°F0"0"
198657°F34°F0.28"0"
198585°F66°F0"0"
198460°F48°F1.27"0"
198358°F37°F0"0"
198263°F34°F0"0"
198155°F42°F0"0"
198085°F56°F0"0"
197983°F56°F0.15"0"
197846°F39°F0"0"
197779°F59°F0.86"0"
197676°F54°F0.51"0"
197565°F37°F0"0"
197482°F58°F1.27"0"
197380°F65°F0.13"0"
197269°F54°F1.17"0"
197187°F52°F1.3"0"

April 21 at Nearby Parks

Holiday Weather at Gateway Arch

Official NPS WebsiteVisit nps.gov/jeff for park information, alerts, and reservations

Explore More at Gateway Arch

See historical weather for other dates

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