Dry weather: only 34 inches of rain and melted snow a year in Onaga, less than in 80% of U.S. towns
July afternoons average 89°. Only 73° separates winter nights from summer afternoons. By January nights alone, it runs colder than 77% of U.S. towns. Tender plants can go out after about April 19; in half of years the first frost comes by October 19.
A year in Onaga at a glance
Each month’s typical high and low, and what it brings.
What stands out about Onaga’s climate
Compared with towns across the U.S., with Onaga’s place in Kansas beside it.
What a year in Onaga feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 182 frost-free days a year
In half of years the last 32° night comes by April 19 and the first by October 19. Frost and day counts come from NOAA’s station at Centralia, KS, 16 miles from the town’s center, 190 ft higher.
The 2023 USDA map puts Onaga’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −6°. 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 15 inches of snow a winter
Snow, measured at Onaga, KS, falls mostly in December. Precipitation (rain plus melted snow) adds up to 34 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 66 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Onaga
80% of the work is heating. Months averaging under 55° run from November 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 Centralia, KS.
Living with Onaga’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
182 frost-free days in zone 6a. The last frost comes by Apr 19 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 19.
Months with highs of 62–84° and lows of 40° or more: April, May, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Onaga from natural hazards, river flooding is the largest share (35%); heat waves, cold waves, winter storms and ice storms together are 12%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Onaga and similar climates
TownRatings has no climate map of the towns around Onaga yet.
Climates most like Onaga’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 |
|---|---|---|---|---|
| Onaga, KS | 17° | 89° | 34" | 15" |
| Boonville, MO | 21° | 88° | 41" | 13" |
| Jacksonville, IL | 19° | 87° | 39" | 16" |
| Fort Madison, IA | 17° | 86° | 39" | 18" |
| Kearney, NE | 14° | 87° | 26" | 22" |
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 Onaga averaged 0.7° warmer than the 1900s. The biggest change is in January (+2.0°).
A smaller shift than in 94% 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 Onaga compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Onaga’s place among Kansas’.
Onaga weather by month
Highs, lows and precipitation from NOAA’s grid at Onaga’s center; snow, wet days and snow on the ground from Onaga, KS. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 38° | 17° | 0.7" | 3.8" | 3 | 22° – 39° |
| February | 43° | 21° | 1.1" | 4.1" | 3 | 24° – 41° |
| March | 55° | 31° | 2.0" | 1.1" | 6 | 36° – 57° |
| April | 66° | 41° | 3.4" | 0.0" | 8 | 45° – 59° |
| May | 75° | 52° | 4.9" | 0.0" | 8 | 58° – 72° |
| June | 85° | 63° | 4.7" | 0.0" | 8 | 69° – 79° |
| July | 89° | 67° | 4.3" | 0.0" | 8 | 72° – 84° |
| August | 88° | 64° | 4.0" | 0.0" | 6 | 70° – 83° |
| September | 80° | 55° | 3.2" | 0.0" | 6 | 62° – 74° |
| October | 68° | 43° | 2.6" | 0.1" | 6 | 48° – 60° |
| November | 53° | 30° | 1.6" | 0.4" | 4 | 35° – 50° |
| December | 42° | 21° | 1.2" | 5.4" | 2 | 19° – 37° |
| Year | 65° | 42° | 33.6" | 14.9" | 66 |
How much a month can swing
A normal is an average. March swings the most: from 1991 to 2020 its average ranged from 36° to 57°. June is the most reliable, staying within 10°.
Where Onaga’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 Onaga’s center.
- Snow: Onaga, KS (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Centralia, KS, 16 miles from the town’s center, 190 ft higher; 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 Onaga’s climate
What is the weather like in Onaga?
A typical July afternoon reaches 89°, a January night drops to 17°, and about 15 inches of snow falls in a normal winter. Colder January nights than 77% of U.S. towns; hotter July afternoons than 74% of U.S. towns.
How cold does it get in Onaga in winter?
January nights average 17°. About 123 nights a year reach 32° or below and 6 reach 0° or below. In the coldest January of the last 30 years the month averaged 22°.
How much snow does Onaga get?
About 15 inches in a normal winter at Onaga, KS, most of it in December.
How hot does it get in Onaga?
July, with a typical high of 89° and a low of 67°. About 37 days a year reach 90° and 4 reach 100° (Centralia, KS).
When is the first and last frost in Onaga?
In half of years the last spring frost (32°) comes by April 19 and the first fall frost by October 19, about 182 frost-free days, at Centralia, KS.
What growing zone is Onaga in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −6°.
What is the best time of year to visit Onaga?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Onaga getting warmer?
Yes: 1991–2020 averaged 0.7° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 94% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Onaga.
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.