Byron’s winters are colder but less snowy than most of the U.S.
A typical July afternoon reaches 88°, a January night drops to 9°, and about 13 inches of snow falls in a normal winter.
A year in Byron at a glance
Each month’s typical high and low, and what it brings.
What stands out about Byron’s climate
Compared with towns across the U.S., with Byron’s place in Wyoming beside it.
What a year in Byron feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 142 frost-free days a year
In half of years the last 32° night comes by May 9 and the first by September 29. Frost and day counts come from NOAA’s station at Lovell, WY, 6 miles from the town’s center, 170 ft lower.
The 2023 USDA map puts Byron’s center in zone 5a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −20°. 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 13 inches of snow a winter
Snow, measured at Lovell, WY, falls mostly in January. Precipitation (rain plus melted snow) adds up to 7 inches a year; May is the wettest month and December the driest. Rain or snow falls on about 45 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Byron
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 Lovell, WY.
Living with Byron’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
142 frost-free days in zone 5a. 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 Sep 29.
Months with highs of 62–84° and lows of 40° or more: May, June and September. 0.5 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Byron from natural hazards, river flooding is the largest share (67%); heat waves, cold waves, winter storms and ice storms together are 18%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Byron and similar climates
TownRatings has no climate map of the towns around Byron yet.
Climates most like Byron’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 |
|---|---|---|---|---|
| Byron, WY | 9° | 88° | 7" | 13" |
| Shelley, ID | 14° | 87° | 11" | 15" |
| Vernal, UT | 9° | 90° | 9" | 20" |
| Zuni Pueblo, NM | 16° | 89° | 11" | 10" |
| Montrose, CO | 15° | 90° | 10" | 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 Byron averaged 1.9° warmer than the 1900s. The biggest change is in January (+4.3°).
A bigger shift than in 84% 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 Byron compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Byron’s place among Wyoming’s.
Byron weather by month
Highs, lows and precipitation from NOAA’s grid at Byron’s center; snow, wet days and snow on the ground from Lovell, WY. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 32° | 9° | 0.3" | 3.5" | 2 | 6 | 8° – 32° |
| February | 37° | 13° | 0.3" | 2.8" | 3 | 5 | 11° – 36° |
| March | 50° | 23° | 0.3" | 1.2" | 3 | 2 | 26° – 44° |
| April | 59° | 31° | 0.8" | 0.7" | 5 | 0 | 40° – 50° |
| May | 68° | 41° | 1.3" | 0.1" | 7 | 0 | 50° – 59° |
| June | 79° | 50° | 1.2" | 0.0" | 7 | 0 | 57° – 71° |
| July | 88° | 56° | 0.6" | 0.0" | 4 | 0 | 62° – 77° |
| August | 86° | 53° | 0.4" | 0.0" | 3 | 0 | 64° – 74° |
| September | 75° | 44° | 0.9" | 0.1" | 4 | 0 | 55° – 65° |
| October | 59° | 32° | 0.8" | 0.8" | 4 | 0 | 37° – 52° |
| November | 44° | 20° | 0.3" | 1.5" | 2 | 2 | 20° – 41° |
| December | 33° | 11° | 0.2" | 2.6" | 2 | 3 | 12° – 27° |
| Year | 59° | 32° | 7.4" | 13.3" | 45 | 18 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 11° to 36°. May is the most reliable, staying within 10°.
Where Byron’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 Byron’s center.
- Snow: Lovell, WY.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Lovell, WY, 6 miles from the town’s center, 170 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 Byron’s climate
What is the weather like in Byron?
A typical July afternoon reaches 88°, a January night drops to 9°, and about 13 inches of snow falls in a normal winter. Colder January nights than 94% of U.S. towns; hotter July afternoons than 65% of U.S. towns.
How cold does it get in Byron in winter?
January nights average 9°. About 182 nights a year reach 32° or below and 21 reach 0° or below. In the coldest January of the last 30 years the month averaged 8°.
How much snow does Byron get?
About 13 inches in a normal winter at Lovell, WY, most of it in January, with snow on the ground about 18 days a year.
How hot does it get in Byron?
July, with a typical high of 88° and a low of 56°. About 25 days a year reach 90° (Lovell, WY).
When is the first and last frost in Byron?
In half of years the last spring frost (32°) comes by May 9 and the first fall frost by September 29, about 142 frost-free days, at Lovell, WY.
What growing zone is Byron in?
Zone 5a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −20°.
What is the best time of year to visit Byron?
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 Byron getting warmer?
Yes: 1991–2020 averaged 1.9° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 84% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Byron.
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.