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Olathe weather by month: averages, rainfall & climate trends

Olathe swings through a wide annual range, with 50.3°F between the monthly means of its warmest and coldest months. The heavier rain months run from March to October. Olathe weather by month: average temperatures, rainfall, extremes and how the climate has changed since 1940.

Today vs average

+14.8°Fhigh well above average

78° / 55°Today
63° / 44°Average
see today in detail →

How it's changed

+3.1°Faverage temperature, 2016–2025 vs 1940–1949average temperature vs 1940–4984frost days a year now (2016–2025) · 104 in the 1940sfrost days a year · 104 in the 1940s68days above 86°F a year now (2016–2025) · 47 in the 1940sdays above 86°F · 47 in the 1940s+3.1°F vs the 1940s · see how it's changed →
Weather by montha typical year, averaged over the full recordJanuary, rain 1.6 incheshigh 38°low 21°February, rain 1.8 incheshigh 44°low 25°March, rain 3.3 incheshigh 55°low 35°April, rain 4.4 incheshigh 66°low 46°May, rain 5.2 incheshigh 75°low 56°June, rain 4.9 incheshigh 84°low 66°July, rain 3.4 incheshigh 88°low 70°August, rain 3.3 incheshigh 87°low 68°September, rain 3.7 incheshigh 79°low 60°October, rain 3.4 incheshigh 68°low 49°November, rain 2.3 incheshigh 54°low 36°December, rain 1.8 incheshigh 42°low 26°wettest month May, 5.2 inches · 39.1 inches a yearsee month by month →

Right now

What it's doing today vs the historical average for this date.
Overcast

Right now

64.2°

62°feels like
63%humidity
51°dew point
6 mphfrom SE
UV index0.0
sunrise07:39sunset18:27day length10h 48m
SunMostly clear78°55°
TodayClear77°57°
TueOvercast71°58°
WedClear77°58°
ThuOvercast78°61°
FriDrizzle73°61°
SatDrizzle61°55°

On this date: October 26

Today (forecast)
78° / 55°
Average for October 26
63° / 44°

High well above average · +14.8°F

  • Highest since 1940: 84.8° · 2014
  • Lowest since 1940: 26.7° · 1942
  • One year ago: 54° / 52°

Every October 26 in history, coldest to hottest

▲ Daily highs▼ Daily lows

Dots show daily highs (top) and lows (bottom) for each October 26 on record (n = 87). Outlined dots are today's forecast.

Area we sample

Each city's history comes from one ERA5 grid cell, about 28 km across, shown by the dashed box. Near mountains or coasts, conditions can vary across the cell.

Location & data

Historical weather for Olathe is sampled from the ECMWF ERA5 reanalysis at 38.88°N, 94.82°W, with daily records since 1940.

Coordinates
38.88°N, 94.82°W
Time zone
America/Chicago
Period
1940–2026
Data source
ERA5 (ECMWF)

Last 30 days

24 of the last 31 days were warmer than the historical average for that date. Average difference: +6.3°F.

Each bar is one day, from morning low to afternoon high. Warm-colored bars are days whose mean ran above average; cool bars ran below. The dot inside the bar is the daily mean. The shaded band is the typical 10–90% range expected for that date. Average = the day's mean temperature averaged across every year of record (1940–2026) for that calendar date.

This date over the years

One dot per year, showing the mean temperature on this calendar date. Dots are warmer or cooler than the long-term average (dashed line); the shaded band is the typical 10–90% range, and the highlighted dot is today's forecast. Based on ERA5 reanalysis: modelled estimates, not station readings.

Weather by month

Average temperatures and rainfall for each month: a typical year, from the full record.

Climate overview

The year peaks in July, at around 88.3°F by mid-afternoon, with nights around 69.9°F. On about 65 nights a year, the temperature never drops below 68°F. The coolest month is January, when afternoons reach about 38.2°F and overnight lows sit around 21.2°F. Around 85 days a year dip below freezing.

The yearly total for Olathe comes to about 39.1 inches; monthly amounts range from 1.6 inches in January up to 5.2 inches in May.

The record here starts in 1940, and since then the annual mean in Olathe has climbed 3.1°F from the first ten years to the last ten. The count of days past 86°F has risen from roughly 45 a year to 70 between the record's first and last decades.

Climate graph (climograph)

July is the warmest month, January the coolest: a yearly swing of 50°F. Wettest month: May (~5.2 in). Whole year averages ~39.1 inches of rain.

Bars = average monthly rainfall (right axis). Lines = average daily high and low (left axis). Average = each month's value averaged across every year of record (1940–2026).

Rainy days by month

About 85 rainy days a year: most in May (~11), fewest in January (~5).

Bars = average number of days with ≥ 0.08 in per month. Hover for the monthly rainfall total.

Monthly wind

Average daily peak wind at 10 m, by month.

Monthly solar energy

Average daily incoming solar energy in megajoules per square metre: the record's own proxy for how sunny the month is.

Olathe month by month: what to expect

Typical conditions for each month, averaged across the full record (since 1940). Daylight is the time from sunrise to sunset. Highest and Lowest are the most extreme values in the ERA5 dataset (modelled since 1940), so they can differ from official weather-station readings.

MonthAvg highAvg lowRainRainy daysDaylightHighestLowest
January38.2°21.2°1.6 in59.6 h72.8° (2013)−20.4° (1947)
February43.6°25.5°1.8 in510.5 h77.9° (1972)−15.9° (1982)
March54.5°34.9°3.3 in811.7 h84.7° (1986)−10.0° (1948)
April66.1°45.7°4.4 in1013.0 h90.2° (1987)15.2° (1975)
May74.7°56.1°5.2 in1114.1 h94.8° (1956)29.5° (1976)
June83.9°65.8°4.9 in1014.7 h104.0° (1980)45.5° (2012)
July88.3°69.9°3.4 in714.5 h108.4° (1954)49.5° (1972)
August87.1°68.1°3.3 in713.5 h106.0° (2011)47.0° (1950)
September79.3°59.6°3.7 in712.2 h101.1° (1954)32.0° (1942)
October68.1°48.5°3.4 in711.0 h93.3° (2006)19.3° (1993)
November53.5°36.3°2.3 in59.8 h80.0° (2006)−1.4° (1952)
December42.2°26.1°1.8 in59.3 h72.3° (2021)−25.8° (1989)

How it's changed

Year-by-year signals from 1940 to today.

Climate stripes

Annual mean shifted from 1940–1949 to 2016–2025 by +3.1°F.

Each vertical stripe is one year. Color encodes how much that year's annual mean differed from the long-term average. Average = each year's annual mean compared to the average of all years (1940–2026). cooler ← → warmer

Annual mean temperature

Long-term trend: +0.31°F per decade.

One point per year, showing the temperature averaged across the whole year. The dashed line is the least-squares long-term trend. Based on ERA5 reanalysis: modelled estimates, not station readings.

Seasonal warming

Mar–May is warming fastest: +0.50°F per decade.

Each faint line is one three-month period's average per year; the bold dashed line is its long-term trend. Different parts of the year often warm at different rates. Based on ERA5 reanalysis: modelled estimates, not station readings.

Hot days vs frost days

Days ≥ 86°F per year: 46.5 early in the record → 68.2 recently. Frost days: 104 → 84.

Thin lines are raw yearly counts; thick lines are the smoothed trend that removes year-to-year noise. The hot-day threshold is auto-picked per city so the line actually moves. Average = a centered 5-year rolling average to smooth weather noise.

Yearly hot & cold extremes

Hottest day since 1940 in 1954, coldest in 1989: 108.4°F / −25.8°F.

One point per year: the single hottest and coldest day recorded that year.

Annual rainfall

~39.1 in/year on average. Last decade: +5% vs that average. Long-term trend: +0.73 in per decade.

One bar per year of total rainfall. Dashed line is the long-term average. Average = the average annual rainfall across every year of record (1940–2026).

Day-by-day grid

Each tiny square is one calendar day across the full record, about 30,000 days per city. Use the mode switch above the chart: Anomaly colors each day by how far it ran from the historical average for that date (red = warmer, blue = cooler), Daily mean temp shows the absolute mean temperature for the day (useful to see seasons and heatwaves), and Precipitation shows daily rainfall (useful to spot wet/dry seasons and droughts). Average = the long-term average for that calendar date (1940–2026).

Frequently asked questions about Olathe

Which is the warmest month in Olathe?
On long-term average, the warmest month in Olathe is July (mean daily temperature of about 78.5°F) and the coolest is January (about 28.2°F).
How does today's temperature in Olathe compare to the historical average?
On October 26, 2026, Olathe is forecast to reach a high of 77.7°F and a low of 54.5°F. The long-term average for this date (the full record since 1940) is a high of 62.9°F and a low of 44.5°F, so today's high is 14.8°F warmer than that average.
How much has Olathe warmed since 1940?
Comparing the first decade of the record (1940–1949) with the most recent (2016–2025), the annual mean temperature in Olathe is about 3.1°F warmer.
How much does it rain in Olathe?
Olathe receives about 39.1 inches of precipitation per year on long-term average, with May typically the wettest month.
What is the average temperature in Olathe?
Over the full record (since 1940), the annual mean temperature in Olathe is about 54.7°F. The warmest month is July and the coolest is January.
What are the average temperatures in Olathe by month?
Average daily highs and lows for each month in Olathe (°F, full record since 1940): January 38°/21°, February 44°/25°, March 55°/35°, April 66°/46°, May 75°/56°, June 84°/66°, July 88°/70°, August 87°/68°, September 79°/60°, October 68°/49°, November 54°/36°, December 42°/26°.
What is the weather like in Olathe in summer?
June to August is summer in Olathe, and it is hot. Daytime highs sit at 84–88°F and nights at 66–70°F; July is the warmest month. Rain is steady at around 3.8 inches a month, spread over roughly 8 days.
What is the weather like in Olathe in winter?
In winter, December through February, Olathe is cold. Afternoons run 38–44°F and nights 21–26°F; January is the coldest month. Rain and snow fall on about 5 days a month, adding up to around 1.7 inches. No season is drier.
What is the weather like in Olathe in spring?
March to May is spring in Olathe, and it is wet and mild. March is still 55°F in the afternoon and 35°F at night, May already 75°F and 56°F. Rain picks up through the season: 8 rainy days and 3.3 inches in March, 11 days and 5.2 inches in May.
What is the weather like in Olathe in autumn?
September to November is autumn in Olathe, and it is mild. September still brings 79°F afternoons and 60°F nights, November only 54°F and 36°F. Rain falls off from 3.7 inches on 7 days in September to 2.3 inches on 5 days in November.
How many days a year does it rain in Olathe?
On long-term average, Olathe has about 85 days a year with at least 0.08 inches of rain or snow. The annual total is roughly 39.1 inches.

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