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Weather on September 20

San Bernardino, CA

55 Years of Data

Avg High
88°F
Avg Low
59°F
Warmest
2015
85°F avg
Coldest
1988
57°F avg

About This Date

September 20th in San Bernardino, CA typically brings warm fall weather, with average highs around 88°F and lows near 59°F — a 29°F daily swing. Over 48 years of records, the warmest September 20th was in 2015 (85°F average), while the coldest was 1988 (57°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 4% of September 20th dates historically.

Planning for September 20th in San Bernardino, CA? Stay hydrated and seek shade during peak afternoon hours.

YearHighLowAvgPrecipSnow
202591°64°78°
201772°60°66°
201681°67°74°
2015warmest99°71°85°
201482°62°72°
201378°61°69°
2012102°64°83°
201195°60°78°
201092°54°73°
200994°59°76°
200885°58°71°
200771°56°63°
200687°53°70°
200578°64°71°0.46"
200477°53°65°
200399°59°79°
200296°58°77°
200191°57°74°
200088°63°75°
199995°51°73°
199874°60°67°
199787°60°74°
199691°59°75°
199595°59°77°
199489°57°73°
199378°56°67°
199297°59°78°
199191°65°78°
199078°62°70°
198982°50°66°
1988coldest60°54°57°0.15"
198795°60°78°
198673°53°63°
198591°56°73°
198499°69°84°
198385°67°76°
198294°55°74°
198196°
198087°55°71°
1979103°64°83°
197884°65°74°
197781°53°67°
197678°63°70°
197595°62°79°
197496°59°78°
197382°54°68°
197297°51°74°
197190°49°69°
48 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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