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Weather on April 21

San Bernardino, CA

55 Years of Data

Avg High
78°F
Avg Low
50°F
Warmest
2009
80°F avg
Coldest
2010
49°F avg

About This Date

April 21st in San Bernardino, CA typically brings pleasant spring weather, with average highs around 78°F and lows near 50°F — a 28°F daily swing. Over 49 years of records, the warmest April 21st was in 2009 (80°F average), while the coldest was 2010 (49°F) — a 31°F range across recorded history. Rain or other precipitation has occurred on about 16% of April 21st dates historically, with the wettest April 21st recording 1.32" of rain.

Planning for April 21st in San Bernardino, CA? Great weather for outdoor activities.

Warming Trend
0.9°F per decade on this date
YearHighLowAvgPrecipSnow
202677°52°65°
202581°51°66°
201786°62°74°
201682°55°69°
201577°50°64°
201487°56°71°
201391°52°71°
201297°57°77°
201170°54°62°
2010coldest56°43°49°0.3"
2009warmest100°60°80°
200874°42°58°
200763°44°53°0.94"
200680°47°63°
200585°44°64°
200470°48°59°
200368°44°56°
200285°45°65°
200159°45°52°1.3"
200066°51°59°
199981°54°67°
199893°56°74°
199788°57°72°
199674°46°60°
199571°43°57°
199474°56°65°
199388°55°71°
199280°53°67°
199171°49°60°0.03"
199074°56°65°
198977°55°66°
198862°45°53°0.23"
198791°51°71°
198689°55°72°
198557°49°53°
198481°58°69°
198367°50°58°1.32"
198275°58°66°
198185°47°66°0.03"
198071°56°63°
197984°46°65°
197869°51°60°
197785°45°65°
197686°50°68°
197576°48°62°
197485°44°64°
197378°44°61°
197283°42°62°
197158°47°52°0.1"
49 years of data from NORTON AFB

San Bernardino, CA Temperature Range by Month

Average monthly highs and lows. The shaded band shows the typical daily temperature range.

30°50°70°90°110°JFMAMJJASOND
Avg high Avg low

San Bernardino, CA Monthly Precipitation

Average rainfall and snowfall per month, in inches.

0"5.8"11.6"JFMAMJJASOND0.1"0"
Rain (in) Snow (in)

San Bernardino, CA Daily Temperature Calendar

Average daily high temperature for every day of the year. Each cell is the climatological mean for that calendar day across 55 years of NOAA data.

151015202531JanFebMarAprMayJunJulAugSepOctNovDec
Cooler
Hotter
20°40°60°80°100°

Best Time to Visit San Bernardino, CA

San Bernardino, CA has no months that meet our "pleasant" threshold — every season has tradeoffs.

Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Pleasant (65-82°F, ≤2.5" rain) Mild Less ideal

Browse Weather History

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

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