Olathe averages 33.2 days a year above 90°F, with May the wettest month at 5.38 in of normal rain. The hottest day on record was 110°F on Aug 2, 2011; the coldest, −13°F on Feb 16, 2021. The single biggest 24-hour rain event recorded was 4.61 in on Sep 13, 1998.
Climate and Average Weather Year Round in Olathe
Year-round temperature
In Olathe, the warmest months are June through September, with average daily highs between 78°F and 88°F. The coldest stretch runs December through February, with highs between 39°F and 44°F and overnight lows reaching 21°F.
Rainfall through the year
Rainfall in Olathe averages 3.1 in per month over the long run. May is the wettest at 5.4 in, while January is the driest at 1.1 in.
Days at 90 °F or hotter
Olathe averages 33.2 days per year at 90 °F or hotter. The hottest year on record saw 62 such days (2012); the coolest just 3 (2026).
Precipitation this year
As of May 28, Olathe has received 18.7 in of precipitation this year — 39% above the long-term normal for this point in the year (13.5 in).