Hartrandt sits near the bottom of U.S. towns for precipitation, with 12 inches a year
On a normal July day the thermometer tops out near 88°. Winter nights are cold: in January they are colder than in 85% of U.S. towns. Compared with 1901–2000, the average now sits 1.7° higher. If you like long walks, June and September offer highs of 76–79°.
A year in Hartrandt at a glance
Each month’s typical high and low, and what it brings.
What stands out about Hartrandt’s climate
Compared with towns across the U.S., with Hartrandt’s place in Wyoming beside it.
What a year in Hartrandt feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 117 frost-free days a year
In half of years the last 32° night comes by May 26 and the first by September 22. Frost and day counts come from NOAA’s station at Casper Natrona Co Airport, 6 miles from the town’s center, at about the same height.
The 2023 USDA map puts Hartrandt’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −18°. 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 72 inches of snow a winter
Snow, measured at Casper Natrona Co Airport, falls mostly in February, March, April and December. Precipitation (rain plus melted snow) adds up to 12 inches a year; May is the wettest month and January the driest. Rain or snow falls on about 91 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Hartrandt
94% of the work is heating, so the furnace matters far more than the air conditioner. Months averaging under 55° run from October through May.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Casper Natrona Co Airport.
Living with Hartrandt’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
117 frost-free days in zone 5a. The last frost comes by May 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 Sep 22.
Months with highs of 62–84° and lows of 40° or more: June and September.
Parks & trails →Of the yearly building losses FEMA expects in Hartrandt from natural hazards, river flooding is the largest share (51%); heat waves, cold waves, winter storms and ice storms together are 18%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Hartrandt and its neighbors
Every town next door is within a degree of Hartrandt in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Hartrandt’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 |
|---|---|---|---|---|
| Hartrandt, WY | 15° | 88° | 12" | 72" |
| Heber, UT | 12° | 88° | 15" | 75" |
| Erie, CO | 18° | 89° | 14" | 65" |
| Preston, ID | 14° | 89° | 15" | 52" |
| Billings, MT | 15° | 89° | 14" | 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 Hartrandt averaged 1.7° warmer than the 1900s. The biggest change is in March (+4.0°).
A bigger shift than in 69% 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 Hartrandt compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Hartrandt’s place among Wyoming’s.
Hartrandt weather by month
Highs, lows and precipitation from NOAA’s grid at Hartrandt’s center; snow, wet days and snow on the ground from Casper Natrona Co Airport. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 37° | 15° | 0.5" | 9.0" | 6 | 17 | 20° – 32° |
| February | 39° | 16° | 0.5" | 10.9" | 7 | 12 | 20° – 34° |
| March | 50° | 24° | 0.8" | 10.3" | 8 | 6 | 28° – 44° |
| April | 57° | 29° | 1.4" | 10.5" | 10 | 3 | 37° – 49° |
| May | 67° | 38° | 2.2" | 2.6" | 11 | 1 | 47° – 59° |
| June | 79° | 47° | 1.3" | 0.1" | 9 | 0 | 56° – 69° |
| July | 88° | 54° | 1.0" | 0.0" | 7 | 0 | 64° – 75° |
| August | 86° | 52° | 0.8" | 0.0" | 6 | 0 | 64° – 73° |
| September | 76° | 43° | 1.0" | 1.5" | 7 | 0 | 54° – 65° |
| October | 60° | 32° | 1.1" | 7.0" | 8 | 2 | 38° – 53° |
| November | 46° | 22° | 0.6" | 8.9" | 6 | 7 | 22° – 43° |
| December | 37° | 15° | 0.5" | 11.0" | 7 | 16 | 17° – 30° |
| Year | 60° | 32° | 11.7" | 71.8" | 91 | 64 |
How much a month can swing
A normal is an average. November swings the most: from 1991 to 2020 its average ranged from 22° to 43°. August is the most reliable, staying within 9°.
Where Hartrandt’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 Hartrandt’s center.
- Snow: Casper Natrona Co Airport.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Casper Natrona Co Airport, 6 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 Hartrandt’s climate
What is the weather like in Hartrandt?
A typical July afternoon reaches 88°, a January night drops to 15°, and about 72 inches of snow falls in a normal winter. Colder January nights than 85% of U.S. towns; hotter July afternoons than 70% of U.S. towns.
How cold does it get in Hartrandt in winter?
December nights average 15°. About 183 nights a year reach 32° or below and 15 reach 0° or below. In the coldest December of the last 30 years the month averaged 17°.
How much snow does Hartrandt get?
About 72 inches in a normal winter at Casper Natrona Co Airport, most of it in February, March, April and December, with snow on the ground about 64 days a year.
How hot does it get in Hartrandt?
July, with a typical high of 88° and a low of 54°. About 38 days a year reach 90° and 1 reach 100° (Casper Natrona Co Airport).
When is the first and last frost in Hartrandt?
In half of years the last spring frost (32°) comes by May 26 and the first fall frost by September 22, about 117 frost-free days, at Casper Natrona Co Airport.
What growing zone is Hartrandt in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −18°.
What is the best time of year to visit Hartrandt?
By one simple rule (highs of 62–84° and lows of 40° or more), June and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Hartrandt getting warmer?
Yes: 1991–2020 averaged 1.7° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 69% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Hartrandt.
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.