Photo: Jguy10218 · CC BY-SA 4.0Highlands Ranch’s winters are colder and snowier than most of the U.S.
A typical July afternoon reaches 87°, a January night drops to 20°, and about 64 inches of snow falls in a normal winter.
A year in Highlands Ranch at a glance
Each month’s typical high and low, and what it brings.
What stands out about Highlands Ranch’s climate
Compared with towns across the U.S., with Highlands Ranch’s place in Colorado beside it.
What a year in Highlands Ranch feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 143 frost-free days a year
In half of years the last 32° night comes by May 9 and the first by October 2. Frost and day counts come from NOAA’s station at Castle Rock, CO, 10 miles from the city’s center point, 390 ft higher.
The 2023 USDA map puts Highlands Ranch’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −10°. 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 64 inches of snow a winter
Snow, measured at Highlands Ranch 3.2 Ese, CO, falls mostly in February and April. Precipitation (rain plus melted snow) adds up to 17 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 93 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Highlands Ranch
92% 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 Castle Rock, CO.
Living with Highlands Ranch’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
143 frost-free days in zone 6a. The last frost comes by May 9 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 2.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 39 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Highlands Ranch from natural hazards, river flooding is the largest share (40%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Highlands Ranch and its neighbors
Littleton the hottest July afternoons (89°, 2° warmer). Differences under a degree are within what the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Highlands Ranch’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 |
|---|---|---|---|---|
| Highlands Ranch, CO | 20° | 87° | 17" | 64" |
| Pocatello, ID | 19° | 87° | 15" | 64" |
| Doney Park, AZ | 17° | 86° | 16" | 52" |
| Altamont, OR | 22° | 86° | 13" | 52" |
| Suncrest, WA | 23° | 87° | 16" | 48" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Highlands Ranch averaged 1.4° warmer than the 1900s. The biggest change is in March (+3.3°).
A bigger shift than in 52% 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. In a city of 102,000 people, part of the change is the city itself: pavement and buildings hold heat (the urban heat island).
How Highlands Ranch compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Highlands Ranch’s place among Colorado’s.
Highlands Ranch weather by month
Highs, lows and precipitation from NOAA’s grid at Highlands Ranch’s center; snow, wet days and snow on the ground from Highlands Ranch 3.2 Ese, CO. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 46° | 20° | 0.6" | 8.1" | 5 | 22 | 24° – 38° |
| February | 48° | 21° | 0.7" | 11.6" | 6 | 19 | 29° – 41° |
| March | 55° | 28° | 1.5" | 9.9" | 6 | 11 | 36° – 48° |
| April | 61° | 34° | 2.3" | 10.9" | 9 | 5 | 42° – 53° |
| May | 70° | 43° | 2.4" | 2.5" | 12 | 1 | 50° – 60° |
| June | 82° | 52° | 1.9" | 0.0" | 8 | 0 | 63° – 72° |
| July | 87° | 58° | 2.1" | 0.0" | 11 | 0 | 69° – 76° |
| August | 85° | 56° | 2.0" | 0.0" | 10 | 0 | 67° – 74° |
| September | 78° | 48° | 1.5" | 0.0" | 7 | 0 | 57° – 68° |
| October | 65° | 36° | 1.2" | 6.3" | 7 | 4 | 43° – 56° |
| November | 54° | 27° | 0.8" | 6.1" | 5 | 8 | 32° – 48° |
| December | 46° | 19° | 0.7" | 8.6" | 6 | 19 | 26° – 37° |
| Year | 65° | 37° | 17.4" | 64.0" | 93 | 87 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 32° to 48°. July is the most reliable, staying within 7°.
Where Highlands Ranch’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 Highlands Ranch’s center.
- Snow: Highlands Ranch 3.2 Ese, CO.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Castle Rock, CO, 10 miles from the city’s center point, 390 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 Highlands Ranch’s climate
What is the weather like in Highlands Ranch?
A typical July afternoon reaches 87°, a January night drops to 20°, and about 64 inches of snow falls in a normal winter. Colder January nights than 60% of U.S. towns; hotter July afternoons than 63% of U.S. towns.
How cold does it get in Highlands Ranch in winter?
December nights average 19°. About 167 nights a year reach 32° or below and 7 reach 0° or below. In the coldest December of the last 30 years the month averaged 26°.
How much snow does Highlands Ranch get?
About 64 inches in a normal winter at Highlands Ranch 3.2 Ese, CO, most of it in February and April, with snow on the ground about 87 days a year.
How hot does it get in Highlands Ranch?
July, with a typical high of 87° and a low of 58°. About 23 days a year reach 90° (Castle Rock, CO).
When is the first and last frost in Highlands Ranch?
In half of years the last spring frost (32°) comes by May 9 and the first fall frost by October 2, about 143 frost-free days, at Castle Rock, CO.
What growing zone is Highlands Ranch in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −10°.
What is the best time of year to visit Highlands Ranch?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Highlands Ranch getting warmer?
Yes: 1991–2020 averaged 1.4° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 52% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Highlands Ranch.
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.