Weather on August 21

Riverside, CA

55 Years of Data

Avg High
93°F
Avg Low
62°F
Warmest
1982
89°F avg
Coldest
1989
69°F avg

About This Date

August 21st in Riverside, CA typically brings hot summer weather, with average highs around 93°F and lows near 62°F — a 31°F daily swing. Over 55 years of records, the warmest August 21st was in 1982 (89°F average), while the coldest was 1989 (69°F) — a 20°F range across recorded history. Rain or other precipitation has occurred on about 2% of August 21st dates historically. The last decade has been 3.0°F warmer on this date compared to 20-30 years ago.

The last decade has been 3.0°F warmer on this date compared to 20-30 years ago.

Planning for August 21st in Riverside, CA? Stay hydrated and seek shade during peak afternoon hours.

Warming Trend
0.7°F per decade on this date
YearHighLowAvgPrecipSnow
2025104°70°87°
2024100°66°83°
202385°63°74°0.33"
202289°65°77°
202177°64°71°
2020102°73°88°
2019101°62°81°
201892°67°79°
201790°63°76°
201694°63°78°
201586°67°76°
201492°64°78°
2013101°65°83°
201295°69°82°
201194°59°76°
201098°66°82°
200988°63°75°
200888°62°75°
2007102°62°82°
200698°59°79°
200599°60°79°
200486°60°73°
200390°67°78°
200283°60°71°
200188°59°73°
200091°58°74°
199999°61°80°
1998101°60°80°
199798°62°80°
199697°56°76°
199595°69°82°
199492°61°76°
199393°56°74°
199299°65°82°
199199°59°79°
199089°55°72°
1989coldest81°57°69°
198887°60°74°
198789°56°72°
1986101°67°84°
198595°52°73°
198489°70°79°
198382°65°73°
1982warmest105°74°89°
1981104°64°84°
198090°57°73°
197990°60°75°
197895°57°76°
197795°66°81°
197690°58°74°
197584°56°70°
197484°57°71°
197395°66°81°
197292°58°75°
197190°62°76°
55 years of data from RIVERSIDE CITRUS EXP

Browse Weather History

Weather data provided by NOAA Climate Data Online. Not for critical planning.