Frost dates for Olathe Johnson County Exec Airport, Kansas
Half of years have their last spring frost by April 8, but 1 year in 10 still frosts after April 23.
A frost date is really a percentile from 30 years of records at a nearby weather station: in about half of years a frost still comes after the median date. Both numbers are below, so you can choose the risk yourself.
The odds
Last spring frost
How often a frost still comes on or after each date.
- 1 year in 10
- April 23
- 1 year in 5
- April 18
- 3 years in 10
- April 15
- 2 years in 5
- April 11
- Half of years (the median)
- April 8
First fall freeze
How often the first freeze comes on or before each date.
- 1 year in 10
- October 15
- 1 year in 5
- October 20
- 3 years in 10
- October 23
- 2 years in 5
- October 26
- Half of years (the median)
- October 29
- Growing season
- about 204 days
- Hardiness zone nearby
- 6b
- Summer days
- a usual high of about 30 °C86 °F
- Lettuce and spinach run to seed
- June to September, in hot, long days (how we know)
Summer and rain
A growing garden needs about 25 mm1 in of water a week, rain and watering together. Here is what a normal month brings.
Month by month
- January
- high ~4 °C39 °F · low ~-6 °C21 °F · rain ~27 mm1.1 in
- February
- high ~7 °C44 °F · low ~-4 °C25 °F · rain ~36 mm1.4 in
- March
- high ~13 °C55 °F · low ~2 °C35 °F · rain ~58 mm2.3 in
- April
- high ~18 °C65 °F · low ~7 °C45 °F · rain ~98 mm3.9 in
- May
- high ~23 °C74 °F · low ~13 °C55 °F · rain ~137 mm5.4 in
- June
- high ~28 °C83 °F · low ~18 °C65 °F · rain ~131 mm5.1 in
- July
- high ~31 °C87 °F · low ~20 °C69 °F · rain ~107 mm4.2 in
- August
- high ~30 °C87 °F · low ~20 °C67 °F · rain ~111 mm4.4 in
- September
- high ~26 °C78 °F · low ~15 °C59 °F · rain ~90 mm3.5 in
- October
- high ~19 °C67 °F · low ~8 °C47 °F · rain ~76 mm3 in
- November
- high ~12 °C53 °F · low ~2 °C35 °F · rain ~52 mm2 in
- December
- high ~6 °C42 °F · low ~-4 °C25 °F · rain ~36 mm1.4 in
Where these numbers come from
NOAA NCEI 1991–2020 Climate Normals, the Olathe Johnson County Exec Airport station (listed by NOAA as Olathe Johnson Co Exec Ap, USW00003967), at 38.85, -94.74. These are that station’s own records, unshifted. The further your garden is from it, the less exactly they describe your ground. The planner finds the nearest station to your garden and lowers its confidence with distance, so no number is presented as if it were measured in your garden.
Cold air also pools in low ground on the clear, still nights when frost happens, so a hollow can freeze while a slope a few hundred feet away does not. No table can know that about your garden. A few seasons of your own logged frosts can.
ZIP codes nearest this station
64012, 64030, 64114, 64131, 64145, 64146, 64147, 64734, 66013, 66018, 66021, 66030…
+25 moreShow fewer
66031, 66053, 66061, 66062, 66071, 66083, 66085, 66206, 66207, 66209, 66210, 66211, 66212, 66213, 66214, 66215, 66217, 66218, 66219, 66220, 66221, 66223, 66224, 66226, 66227.
Nearby stations
The nearest stations and how their last-frost dates compare. Together they show how frost varies across your area.
- Kansas City Downtown Airport, MO, last frost by April 4
- Pleasant Hill, MO, last frost by April 8
- Topeka NWS, KS, last frost by April 16
Other stations in Kansas.
- Wichita Jabara Airport, KS, last frost by April 10
When do I plant? · Where the dates come from
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