Photo: Doug Kerr · CC BY-SA 2.0Jacksonville has some of the coolest summers among U.S. towns
Deep winter brings January lows near 11°. By January nights alone, it runs colder than 92% of U.S. towns. Decade by decade the climate has edged up, 1.8° above 1901–2000. Comfortable outdoor weather lasts from May to September, with highs of 65–78°.
A year in Jacksonville at a glance
Each month’s typical high and low, and what it brings.
What stands out about Jacksonville’s climate
Compared with towns across the U.S., with Jacksonville’s place in Vermont beside it.
What a year in Jacksonville 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 14 and the first by October 4. Frost and day counts come from NOAA’s station at Rowe 3ne, MA, 5 miles from the town’s center, 230 ft higher.
The 2023 USDA map puts Jacksonville’s center in zone 5b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −13°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
About 53 inches of rain a year
October is the wettest month and February the driest.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Jacksonville
98% 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 Rowe 3ne, MA.
Living with Jacksonville’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
143 frost-free days in zone 5b. The last frost comes by May 14 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 4.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August and September.
Parks & trails →Of the yearly building losses FEMA expects in Jacksonville from natural hazards, river flooding is the largest share (64%); heat waves, cold waves, winter storms and ice storms together are 18%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Jacksonville and similar climates
TownRatings has no climate map of the towns around Jacksonville yet.
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 Jacksonville averaged 1.8° warmer than the 1900s. The biggest change is in December (+3.5°).
A bigger 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 Jacksonville compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Jacksonville’s place among Vermont’s.
Jacksonville weather by month
Highs, lows and precipitation from NOAA’s grid at Jacksonville’s center. 1991–2020 normals.
| Month | High | Low | Rain + melt | 30-yr range |
|---|---|---|---|---|
| January | 29° | 11° | 3.9" | 10° – 28° |
| February | 32° | 12° | 3.5" | 8° – 28° |
| March | 40° | 20° | 4.1" | 22° – 40° |
| April | 53° | 31° | 4.5" | 36° – 46° |
| May | 65° | 42° | 4.3" | 48° – 58° |
| June | 73° | 50° | 4.9" | 59° – 66° |
| July | 78° | 55° | 4.6" | 62° – 71° |
| August | 76° | 54° | 4.4" | 62° – 69° |
| September | 69° | 47° | 4.7" | 54° – 62° |
| October | 57° | 37° | 5.4" | 42° – 53° |
| November | 45° | 27° | 4.1" | 32° – 42° |
| December | 34° | 17° | 4.7" | 18° – 36° |
| Year | 54° | 34° | 53.1" |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 8° to 28°. June is the most reliable, staying within 6°.
Where Jacksonville’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 Jacksonville’s center.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Rowe 3ne, MA, 5 miles from the town’s center, 230 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 Jacksonville’s climate
What is the weather like in Jacksonville?
A typical July afternoon reaches 78°, a January night drops to 11°. Colder January nights than 92% of U.S. towns; cooler July afternoons than 96% of U.S. towns.
How cold does it get in Jacksonville in winter?
January nights average 11°. About 162 nights a year reach 32° or below and 8 reach 0° or below. In the coldest January of the last 30 years the month averaged 10°.
How hot does it get in Jacksonville?
July, with a typical high of 78°. 90° days are rare: none in a normal year at Rowe 3ne, MA.
When is the first and last frost in Jacksonville?
In half of years the last spring frost (32°) comes by May 14 and the first fall frost by October 4, about 143 frost-free days, at Rowe 3ne, MA.
What growing zone is Jacksonville in?
Zone 5b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −13°.
What is the best time of year to visit Jacksonville?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August and September. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Jacksonville getting warmer?
Yes: 1991–2020 averaged 1.8° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 80% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Jacksonville.
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.