FrostDateByZip

Frost dates for 60513Brookfield, IL

The average last spring frost in Brookfield is April 11 and the average first fall frost is October 31, giving a typical growing season of about 201 days. Dates are based on NOAA 1991-2020 climate normals.

Average last spring frost
Apr 11

Safer after Apr 27 (1-in-10 risk)

Average first fall frost
Oct 31

Possible by Oct 20 (1-in-10 risk)

Growing season
201 days

First frost typically in 2 days

Frost risk by date

NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.

Spring dates: chance of a frost AFTER the date. Fall dates: chance of a frost BEFORE the date.
TemperatureLast spring: 90% / 50% / 10% chanceFirst fall: 10% / 50% / 90% chanceGrowing season (50%)Years with at least one
Light frost (36°F)Apr 9 · Apr 23 · May 8Oct 8 · Oct 21 · Nov 1180 days100%
Frost / freeze (32°F)Mar 30 · Apr 11 · Apr 27Oct 20 · Oct 31 · Nov 14201 days100%
Hard freeze (28°F)Mar 15 · Apr 1 · Apr 14Oct 31 · Nov 11 · Nov 26225 days100%

Planting calendar for Brookfield

Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.

CropTaskWindow
TomatoesStart seeds indoorsMar 11 – May 17
TomatoesTransplant outdoorsApr 27 – Jul 11
PeppersStart seeds indoorsMar 11 – Apr 11
PeppersTransplant outdoorsMay 11 – Jun 11
EggplantStart seeds indoorsMar 28 – Apr 26
EggplantTransplant outdoorsMay 11 – Jun 11
CucumbersSow outdoorsMay 11 – Jul 21
Summer squashSow outdoorsApr 27 – Jun 11
Winter squash & pumpkinsSow outdoorsMay 11 – Jun 11
Snap beansSow outdoorsApr 27 – Aug 13
Sweet cornSow outdoorsApr 27 – Jul 11
Watermelon & cantaloupeSow outdoorsMay 11 – Jun 11
OkraSow outdoorsMay 4 – May 27
PeasSow outdoors (spring)Mar 11 – Apr 26
PotatoesPlant outdoors (spring)Mar 11 – May 11
OnionsStart seeds indoors (spring)Jan 28 – Feb 24
OnionsTransplant outdoors (spring)Mar 28 – Apr 26
BroccoliStart seeds indoors (spring)Feb 21 – Mar 27
BroccoliTransplant outdoors (spring)Mar 28 – Apr 26
BroccoliStart seeds indoors (fall)Jul 1 – Jul 11
BroccoliTransplant outdoors (fall)Jul 31 – Aug 11
CabbageStart seeds indoors (spring)Feb 11 – Mar 11
CabbageTransplant outdoors (spring)Mar 11 – Apr 11
CabbageStart seeds indoors (fall)Jun 21 – Jul 21
CabbageTransplant outdoors (fall)Jul 21 – Aug 21
Leaf lettuceSow outdoors (spring)Mar 11 – May 27
Leaf lettuceSow outdoors (fall)Jul 21 – Sep 6
SpinachSow outdoors (spring)Mar 4 – Apr 17
SpinachSow outdoors (fall)Aug 7 – Sep 11
RadishesSow outdoors (spring)Mar 11 – May 1
RadishesSow outdoors (fall)Jul 21 – Sep 21
KaleSow outdoors (spring)Mar 28 – Apr 17
KaleSow outdoors (fall)Jul 14 – Aug 21
CarrotsSow outdoors (spring)Apr 11 – May 27
CarrotsSow outdoors (fall)Jun 21 – Aug 6
GarlicPlant outdoors (fall)Oct 21 – Nov 21

Where these dates come from

ZIP code 60513 is matched to the NOAA station Chicago Midway Ap, IL, 9 km away, at 612 ft elevation (8 ft lower than the ZIP code's center). Nearby stations for comparison:

StationElevationAvg last frostAvg first frost
Chicago Midway Ap, IL (used)612 ftApr 11Oct 31
Chicago Midway Ap 3Sw, IL620 ftApr 10Nov 1
Little Red School Hse, IL715 ftApr 19Oct 22
Wheaton 3 Se, IL680 ftApr 27Oct 17

Frost dates near Brookfield

Frequently asked questions

When is the last frost in Brookfield, IL?
For ZIP code 60513, the average last spring frost (32°F) is April 11, based on NOAA 1991-2020 climate normals for the Chicago Midway Ap, IL weather station. There is a 1-in-10 chance of a frost after April 27.
When is the first frost in Brookfield, IL?
The average first fall frost (32°F) is October 31. There is a 1-in-10 chance of frost by October 20, so tender plants are at risk from that point on.
How long is the growing season in 60513?
In half of years, the frost-free season (between the last and first 32°F frost) is at least 201 days long.
Are these frost dates a forecast?
No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.