Photo: Brian Stansberry · CC BY 3.0Grimsley’s winters are milder and less snowy than most of the U.S.
A typical July afternoon reaches 83°, a January night drops to 26°, and about 13 inches of snow falls in a normal winter.
A year in Grimsley at a glance
Each month’s typical high and low, and what it brings.
What stands out about Grimsley’s climate
Compared with towns across the U.S., with Grimsley’s place in Tennessee beside it.
What a year in Grimsley feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 188 frost-free days a year
In half of years the last 32° night comes by April 17 and the first by October 23. Frost and day counts come from NOAA’s station at Allardt, TN, 10 miles from the town’s center, at about the same height.
The 2023 USDA map puts Grimsley’s center in zone 7a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 2°. 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 Allardt, TN, is heaviest from January through February, about 4 inches a month. Precipitation (rain plus melted snow) adds up to 58 inches a year; December is the wettest month and October the driest. Rain or snow falls on about 142 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Grimsley
83% of the work is heating. Months averaging under 55° run from November through March.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Allardt, TN.
Living with Grimsley’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
188 frost-free days in zone 7a. The last frost comes by Apr 17 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 23.
Months with highs of 62–84° and lows of 40° or more: April, May, June, July, August, September and October.
Parks & trails →Cold waves are 25% of the yearly building losses FEMA expects in Grimsley from natural hazards, the largest share. Normals are averages; the hazards page covers the extremes.
Natural hazards →Grimsley and similar climates
TownRatings has no climate map of the towns around Grimsley yet.
Climates most like Grimsley’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 |
|---|---|---|---|---|
| Grimsley, TN | 26° | 83° | 58" | 13" |
| Etowah, NC | 27° | 84° | 61" | 6.7" |
| Galax, VA | 25° | 82° | 48" | 17" |
| Schuylkill Haven, PA | 20° | 84° | 51" | 21" |
| Martinsville, NJ | 22° | 86° | 50" | 21" |
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 Grimsley averaged 1.0° warmer than the 1900s. The biggest change is in December (+2.1°).
A smaller shift than in 80% 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 Grimsley compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Grimsley’s place among Tennessee’s.
Grimsley weather by month
Highs, lows and precipitation from NOAA’s grid at Grimsley’s center; snow, wet days and snow on the ground from Allardt, TN. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 44° | 26° | 5.0" | 4.0" | 13 | 4 | 27° – 42° |
| February | 48° | 29° | 5.1" | 3.8" | 12 | 3 | 28° – 47° |
| March | 57° | 36° | 5.6" | 2.4" | 13 | 1 | 39° – 57° |
| April | 67° | 44° | 5.3" | 0.4" | 12 | 0 | 50° – 61° |
| May | 74° | 52° | 4.8" | 0.0" | 13 | 0 | 57° – 69° |
| June | 81° | 60° | 5.2" | 0.0" | 13 | 0 | 67° – 75° |
| July | 83° | 64° | 5.5" | 0.0" | 13 | 0 | 70° – 77° |
| August | 83° | 62° | 4.2" | 0.0" | 11 | 0 | 68° – 78° |
| September | 78° | 56° | 4.1" | 0.0" | 9 | 0 | 63° – 73° |
| October | 68° | 44° | 3.2" | 0.1" | 9 | 0 | 53° – 63° |
| November | 57° | 35° | 4.2" | 0.1" | 10 | 0 | 39° – 51° |
| December | 47° | 29° | 5.9" | 2.4" | 14 | 2 | 28° – 50° |
| Year | 65° | 45° | 58.0" | 13.2" | 142 | 11 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 28° to 50°. July is the most reliable, staying within 7°.
Where Grimsley’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 Grimsley’s center.
- Snow: Allardt, TN.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Allardt, TN, 10 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 Grimsley’s climate
What is the weather like in Grimsley?
A typical July afternoon reaches 83°, a January night drops to 26°, and about 13 inches of snow falls in a normal winter. Milder January nights than 66% of U.S. towns; cooler July afternoons than 66% of U.S. towns.
How cold does it get in Grimsley in winter?
January nights average 26°. About 90 nights a year reach 32° or below and 1 reach 0° or below. In the coldest January of the last 30 years the month averaged 27°.
How much snow does Grimsley get?
About 13 inches in a normal winter at Allardt, TN, heaviest from January through February, about 4 inches a month, with snow on the ground about 11 days a year.
How hot does it get in Grimsley?
July, with a typical high of 83° and a low of 64°. About 6 days a year reach 90° (Allardt, TN).
When is the first and last frost in Grimsley?
In half of years the last spring frost (32°) comes by April 17 and the first fall frost by October 23, about 188 frost-free days, at Allardt, TN.
What growing zone is Grimsley in?
Zone 7a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 2°.
What is the best time of year to visit Grimsley?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, July, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Grimsley getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 80% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Grimsley.
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.