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Weather on June 18

Rialto, CA

55 Years of Data

Avg High
89°F
Avg Low
58°F
Warmest
1981
86°F avg
Coldest
1975
58°F avg

About This Date

June 18th in Rialto, CA typically brings warm summer weather, with average highs around 89°F and lows near 58°F — a 31°F daily swing. Over 48 years of records, the warmest June 18th was in 1981 (86°F average), while the coldest was 1975 (58°F) — a 28°F range across recorded history. Rain or other precipitation has occurred on about 4% of June 18th dates historically.

Planning for June 18th in Rialto, CA? Stay hydrated and seek shade during peak afternoon hours.

Warming Trend
0.5°F per decade on this date
YearHighLowAvgPrecipSnow
202599°66°82°
201796°66°81°
201694°63°78°
201594°64°79°
201479°53°66°
201385°60°72°
201287°62°75°
201178°55°67°
201079°54°66°
200985°56°70°
200899°71°85°
200788°58°73°
200690°63°76°
200578°53°66°
200485°54°69°
200384°54°69°
200291°61°76°
200195°64°80°
200087°55°71°
199994°60°77°
199890°54°72°
199797°61°79°
199697°61°79°
199583°52°67°
199493°57°75°
199395°57°76°
199279°53°66°
199181°56°68°
199085°55°70°
1989101°63°82°
198890°54°72°
198786°55°71°
198688°58°73°
198595°60°78°
198493°60°77°
198387°56°71°
198266°58°62°0.08"
1981warmest107°64°86°
198092°57°74°
197978°56°67°
1978100°63°81°
197791°55°73°
197696°57°77°
1975coldest63°53°58°0.23"
197485°52°68°
1973100°54°77°
197289°59°74°
197196°56°76°
48 years of data from DEVORE CALIFORNIA

Rialto, 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

Rialto, CA Monthly Precipitation

Average rainfall and snowfall per month, in inches.

0"6.7"13.3"JFMAMJJASOND0.1"0"
Rain (in) Snow (in)

Rialto, 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 Rialto, CA

Rialto, 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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