Green Castle has colder winter nights than 80% of U.S. towns
In July the day’s top temperature is typically 86°. Expect the heaviest rain or snow in May and the lightest in January. Precipitation is light here, less than falls on 60% of U.S. towns. Homes need heating from November to March, the months averaging under 50°.
A year in Green Castle at a glance
Each month’s typical high and low, and what it brings.
What stands out about Green Castle’s climate
Compared with towns across the U.S., with Green Castle’s place in Missouri beside it.
What a year in Green Castle feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 169 frost-free days a year
In half of years the last 32° night comes by April 26 and the first by October 14. Frost and day counts come from NOAA’s station at Green City 5n, MO, 7 miles from the town’s center, at about the same height.
The 2023 USDA map puts Green Castle’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −11°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
90° days by month
Average days at 90° or more
About 19 inches of snow a winter
Snow, measured at Kirksville, MO, falls mostly in January. Precipitation (rain plus melted snow) adds up to 40 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 104 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Green Castle
88% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through April.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Green City 5n, MO.
Living with Green Castle’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
169 frost-free days in zone 5b. The last frost comes by Apr 26 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Oct 14.
Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Green Castle from natural hazards, river flooding is the largest share (31%); heat waves, cold waves, winter storms and ice storms together are 24%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Green Castle and similar climates
TownRatings has no climate map of the towns around Green Castle yet.
Climates most like Green Castle’s, farther away
TownRatings’ own comparison of NOAA 1991–2020 normals, not a NOAA product: places of 5,000+ at least 150 miles away, one per state, closest on January low, July high, precipitation and snow.
| Town | Jan. low | July high | Precip. | Snow |
|---|---|---|---|---|
| Green Castle, MO | 16° | 86° | 40" | 19" |
| Clinton, IL | 18° | 85° | 39" | 19" |
| Logansport, IN | 18° | 84° | 41" | 19" |
| Van Wert, OH | 19° | 84° | 39" | 17" |
| Lock Haven, PA | 19° | 86° | 41" | 30" |
Temperatures and precipitation come from NOAA’s 5 km grid; snow and day counts from the stations named on this page.
Warmer than it used to be
The last 30 years in Green Castle averaged 0.6° warmer than the 1900s. The biggest change is in December (+2.0°).
A smaller shift than in 96% of U.S. towns.
Change by month
The two periods overlap (1991–2000 is in both), which makes the gap a little smaller than it would be between separate periods.
How Green Castle compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Green Castle’s place among Missouri’s.
Green Castle weather by month
Highs, lows and precipitation from NOAA’s grid at Green Castle’s center; snow, wet days and snow on the ground from Kirksville, MO. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 34° | 16° | 1.3" | 6.0" | 6 | 18° – 36° |
| February | 39° | 20° | 1.6" | 4.6" | 7 | 18° – 41° |
| March | 51° | 30° | 2.5" | 2.2" | 8 | 33° – 54° |
| April | 63° | 41° | 3.9" | 0.8" | 11 | 44° – 58° |
| May | 72° | 52° | 5.7" | 0.0" | 12 | 57° – 71° |
| June | 82° | 61° | 5.2" | 0.0" | 11 | 68° – 75° |
| July | 86° | 65° | 4.5" | 0.0" | 9 | 70° – 83° |
| August | 84° | 63° | 4.3" | 0.0" | 9 | 68° – 79° |
| September | 77° | 55° | 4.1" | 0.0" | 8 | 60° – 72° |
| October | 65° | 43° | 3.1" | 0.1" | 9 | 47° – 59° |
| November | 51° | 31° | 2.3" | 1.3" | 8 | 32° – 50° |
| December | 38° | 21° | 1.7" | 4.0" | 7 | 15° – 38° |
| Year | 62° | 42° | 40.1" | 19.0" | 104 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 15° to 38°. June is the most reliable, staying within 8°.
Where Green Castle’s numbers come from
Normals are 30-year averages, not a forecast. How TownRatings reads climate data →
- Temperatures and precipitation: NOAA’s gridded 1991–2020 normals for the 5 km cell at Green Castle’s center.
- Snow: Kirksville, MO.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Green City 5n, MO, 7 miles from the town’s center, at about the same height; the nearest station that passes our checks for distance, height and agreement with the grid.
- Growing zone: USDA Plant Hardiness Zone Map, 2023. USDA Agricultural Research Service and PRISM Group, Oregon State University, prism.oregonstate.edu/phzm, accessed 8 Oct 2026.
- Then and now: NOAA’s gridded normals for 1901–2000 at the same cell.
- Storms and extremes: FEMA National Risk Index (expected annual losses to buildings).
Common questions about Green Castle’s climate
What is the weather like in Green Castle?
A typical July afternoon reaches 86°, a January night drops to 16°, and about 19 inches of snow falls in a normal winter. Colder January nights than 80% of U.S. towns; hotter July afternoons than 54% of U.S. towns.
How cold does it get in Green Castle in winter?
January nights average 16°. About 139 nights a year reach 32° or below and 12 reach 0° or below. In the coldest January of the last 30 years the month averaged 18°.
How much snow does Green Castle get?
About 19 inches in a normal winter at Kirksville, MO, most of it in January.
How hot does it get in Green Castle?
July, with a typical high of 86° and a low of 65°. About 25 days a year reach 90° and 1 reach 100° (Green City 5n, MO).
When is the first and last frost in Green Castle?
In half of years the last spring frost (32°) comes by April 26 and the first fall frost by October 14, about 169 frost-free days, at Green City 5n, MO.
What growing zone is Green Castle in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −11°.
What is the best time of year to visit Green Castle?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Green Castle getting warmer?
Yes: 1991–2020 averaged 0.6° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 96% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Green Castle.
Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000; USDA/PRISM 2023 hardiness zones; FEMA National Risk Index. Today’s forecast: National Weather Service.