Photo: Jeffrey Beall · CC BY 3.0Hartman reaches 100° on about 15 days a year, more than 93% of U.S. towns
The depth of winter brings overnight lows near 17°. A year here swings 76° from midwinter lows to midsummer highs. Its yearly precipitation falls short of 92% of U.S. towns. Tender plants can go out after about May 1; in half of years the first frost comes by October 12.
A year in Hartman at a glance
Each month’s typical high and low, and what it brings.
What stands out about Hartman’s climate
Compared with towns across the U.S., with Hartman’s place in Colorado beside it.
What a year in Hartman feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 163 frost-free days a year
In half of years the last 32° night comes by May 1 and the first by October 12. Frost and day counts come from NOAA’s station at Holly, CO, 7 miles from the town’s center, 180 ft lower.
The 2023 USDA map puts Hartman’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −9°. 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 22 inches of snow a winter
Snow, measured at Holly, CO, falls mostly in March. Precipitation (rain plus melted snow) adds up to 16 inches a year; July is the wettest month and January the driest. Rain or snow falls on about 60 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Hartman
82% of the work is heating. 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 Holly, CO.
Living with Hartman’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
163 frost-free days in zone 6a. The last frost comes by May 1 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 12.
Months with highs of 62–84° and lows of 40° or more: May and September.
Parks & trails →Of the yearly building losses FEMA expects in Hartman from natural hazards, drought is the largest share (29%); heat waves, cold waves, winter storms and ice storms together are 16%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Hartman and similar climates
TownRatings has no climate map of the towns around Hartman yet.
Climates most like Hartman’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 |
|---|---|---|---|---|
| Hartman, CO | 17° | 94° | 16" | 22" |
| Vineyard, UT | 20° | 92° | 15" | 26" |
| Weiser, ID | 22° | 94° | 13" | 15" |
| McCook, NE | 15° | 92° | 21" | 20" |
| Hereford, TX | 23° | 92° | 19" | 14" |
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 Hartman averaged 1.1° warmer than the 1900s. The biggest change is in March (+2.9°).
A smaller shift than in 70% 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 Hartman compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Hartman’s place among Colorado’s.
Hartman weather by month
Highs, lows and precipitation from NOAA’s grid at Hartman’s center; snow, wet days and snow on the ground from Holly, CO. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 46° | 17° | 0.3" | 4.2" | 2 | 5 | 17° – 39° |
| February | 50° | 20° | 0.3" | 3.4" | 3 | 5 | 24° – 42° |
| March | 60° | 29° | 0.8" | 4.7" | 4 | 2 | 39° – 52° |
| April | 68° | 37° | 1.4" | 1.4" | 6 | 0 | 46° – 57° |
| May | 78° | 48° | 2.0" | 0.7" | 8 | 0 | 57° – 69° |
| June | 89° | 58° | 2.4" | 0.0" | 8 | 0 | 69° – 79° |
| July | 94° | 64° | 3.0" | 0.0" | 8 | 0 | 74° – 84° |
| August | 91° | 62° | 2.7" | 0.0" | 7 | 0 | 71° – 81° |
| September | 84° | 53° | 1.1" | 0.0" | 5 | 0 | 62° – 74° |
| October | 71° | 39° | 1.2" | 1.0" | 4 | 1 | 47° – 60° |
| November | 57° | 26° | 0.5" | 3.2" | 3 | 1 | 34° – 47° |
| December | 47° | 18° | 0.4" | 2.9" | 3 | 5 | 24° – 37° |
| Year | 70° | 39° | 16.0" | 21.5" | 60 | 18 |
How much a month can swing
A normal is an average. January swings the most: from 1991 to 2020 its average ranged from 17° to 39°. August is the most reliable, staying within 10°.
Where Hartman’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 Hartman’s center.
- Snow: Holly, CO.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Holly, CO, 7 miles from the town’s center, 180 ft lower; 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 Hartman’s climate
What is the weather like in Hartman?
A typical July afternoon reaches 94°, a January night drops to 17°, and about 22 inches of snow falls in a normal winter. Colder January nights than 73% of U.S. towns; hotter July afternoons than 92% of U.S. towns.
How cold does it get in Hartman in winter?
January nights average 17°. About 161 nights a year reach 32° or below and 4 reach 0° or below. In the coldest January of the last 30 years the month averaged 17°.
How much snow does Hartman get?
About 22 inches in a normal winter at Holly, CO, most of it in March, with snow on the ground about 18 days a year.
How hot does it get in Hartman?
July, with a typical high of 94° and a low of 64°. About 73 days a year reach 90° and 15 reach 100° (Holly, CO).
When is the first and last frost in Hartman?
In half of years the last spring frost (32°) comes by May 1 and the first fall frost by October 12, about 163 frost-free days, at Holly, CO.
What growing zone is Hartman in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −9°.
What is the best time of year to visit Hartman?
By one simple rule (highs of 62–84° and lows of 40° or more), May and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Hartman getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 70% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Hartman.
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.