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Weather on May 13

Ontario, CA

55 Years of Data

Avg High
82°F
Avg Low
55°F
Warmest
2013
86°F avg
Coldest
1983
54°F avg

About This Date

May 13th in Ontario, CA typically brings warm spring weather, with average highs around 82°F and lows near 55°F — a 27°F daily swing. Over 42 years of records, the warmest May 13th was in 2013 (86°F average), while the coldest was 1983 (54°F) — a 32°F range across recorded history. This date has historically been dry, with little recorded precipitation. The last decade has been 1.6°F cooler on this date compared to 20-30 years ago.

The last decade has been 1.6°F cooler on this date compared to 20-30 years ago.

Planning for May 13th in Ontario, CA? Stay hydrated and seek shade during peak afternoon hours.

Warming Trend
0.5°F per decade on this date
YearHighLowAvgPrecipSnow
202679°58°68°
202569°54°61°
202478°55°67°
202387°54°70°
202293°55°74°
202180°55°68°
202075°55°65°
201978°62°70°
201871°55°63°
201777°56°66°
201688°57°72°
201572°52°62°
201493°57°75°
2013warmest103°69°86°
201285°54°69°
201179°56°67°
201079°56°67°
200981°55°68°
200884°51°68°
200780°51°66°
200682°59°71°
200590°58°74°
200487°55°71°
200377°59°68°
200295°59°77°
200175°55°65°
200085°49°67°
199970°56°63°
198495°53°74°
1983coldest63°46°54°
198274°48°61°
198177°55°66°
198070°43°56°
197997°58°77°
197896°62°79°
197766°44°55°
197698°58°78°
197584°49°66°
197467°52°59°
197369°48°59°
197299°57°78°
197181°50°65°
42 years of data from ONTARIO INTL AP

Ontario, CA Temperature Range by Month

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

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

Ontario, CA Monthly Precipitation

Average rainfall per month, in inches.

0"6.3"12.5"JFMAMJJASOND
Rain (in)

Ontario, 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 Ontario, CA

Ontario, 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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