Photo: Mr. Matté (if there is an issue with this image, contact me using this image's Commons talk page, my Commons user talk page, or my English Wikipedia user talk page; I'll know about it a lot faster) · CC BY-SA 4.0Afternoon heat in Addison trails that of 85% of U.S. towns
Deep winter brings January lows near 19°. May is the wettest month, November the driest. Its yearly precipitation tops that of 72% of U.S. towns. The outdoor season runs from May to September, with highs of 71–81°.
A year in Addison at a glance
Each month’s typical high and low, and what it brings.
What stands out about Addison’s climate
Compared with towns across the U.S., with Addison’s place in Pennsylvania beside it.
What a year in Addison feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 135 frost-free days a year
In half of years the last 32° night comes by May 19 and the first by October 1. Frost and day counts come from NOAA’s station at Chalk Hill 2 Ene, PA, 15 miles from the town’s center, 100 ft lower.
The 2023 USDA map puts Addison’s center in zone 6a: the coldest night of a typical winter, averaged over 1991–2020, reaches about −8°. Plant labels use the zone; frost dates tell you when to plant.
Freezing nights by month
Average nights at or below 32°
About 61 inches of snow a winter
Snow, measured at Confluence 1 Sw Dam, PA, is heaviest from January through February, about 18 inches a month. Precipitation (rain plus melted snow) adds up to 47 inches a year; May is the wettest month and November the driest. Rain or snow falls on about 173 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Addison
96% 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 Chalk Hill 2 Ene, PA.
Living with Addison’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
135 frost-free days in zone 6a. The last frost comes by May 19 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 1.
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 Addison from natural hazards, river flooding is the largest share (91%); heat waves, cold waves, winter storms and ice storms together are 1%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Addison and similar climates
TownRatings has no climate map of the towns around Addison yet.
Climates most like Addison’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 |
|---|---|---|---|---|
| Addison, PA | 19° | 81° | 47" | 61" |
| Saugus, MA | 19° | 82° | 48" | 64" |
| Seabrook, NH | 18° | 81° | 48" | 62" |
| Killingly, CT | 18° | 82° | 50" | 62" |
| Coventry, RI | 19° | 82° | 50" | 62" |
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 Addison averaged 1.0° warmer than the 1900s. The biggest change is in December (+2.4°).
A smaller shift than in 75% 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 Addison compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Addison’s place among Pennsylvania’s.
Addison weather by month
Highs, lows and precipitation from NOAA’s grid at Addison’s center; snow, wet days and snow on the ground from Confluence 1 Sw Dam, PA. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 36° | 19° | 3.6" | 18.3" | 18 | 20 | 20° – 37° |
| February | 40° | 21° | 3.4" | 16.9" | 15 | 17 | 19° – 39° |
| March | 49° | 27° | 4.0" | 10.3" | 15 | 10 | 32° – 48° |
| April | 62° | 36° | 4.1" | 0.9" | 15 | 1 | 44° – 55° |
| May | 71° | 46° | 4.8" | 0.0" | 17 | 0 | 52° – 66° |
| June | 78° | 54° | 4.7" | 0.0" | 15 | 0 | 62° – 69° |
| July | 81° | 59° | 4.6" | 0.0" | 14 | 0 | 66° – 74° |
| August | 80° | 57° | 4.1" | 0.0" | 13 | 0 | 65° – 73° |
| September | 74° | 50° | 3.7" | 0.0" | 12 | 0 | 59° – 67° |
| October | 63° | 39° | 3.3" | 0.2" | 12 | 0 | 48° – 57° |
| November | 51° | 30° | 3.1" | 3.7" | 13 | 3 | 34° – 46° |
| December | 41° | 24° | 3.8" | 10.9" | 16 | 12 | 21° – 43° |
| Year | 60° | 39° | 47.3" | 61.2" | 173 | 62 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 21° to 43°. June is the most reliable, staying within 6°.
Where Addison’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 Addison’s center.
- Snow: Confluence 1 Sw Dam, PA.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Chalk Hill 2 Ene, PA, 15 miles from the town’s center, 100 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 Addison’s climate
What is the weather like in Addison?
A typical July afternoon reaches 81°, a January night drops to 19°, and about 61 inches of snow falls in a normal winter. Colder January nights than 62% of U.S. towns; cooler July afternoons than 85% of U.S. towns.
How cold does it get in Addison in winter?
January nights average 19°. About 138 nights a year reach 32° or below and 6 reach 0° or below. In the coldest January of the last 30 years the month averaged 20°.
How much snow does Addison get?
About 61 inches in a normal winter at Confluence 1 Sw Dam, PA, heaviest from January through February, about 18 inches a month, with snow on the ground about 62 days a year.
How hot does it get in Addison?
July, with a typical high of 81°. 90° days are rare: none in a normal year at Chalk Hill 2 Ene, PA.
When is the first and last frost in Addison?
In half of years the last spring frost (32°) comes by May 19 and the first fall frost by October 1, about 135 frost-free days, at Chalk Hill 2 Ene, PA.
What growing zone is Addison in?
Zone 6a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −8°.
What is the best time of year to visit Addison?
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 Addison getting warmer?
Yes: 1991–2020 averaged 1.0° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 75% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Addison.
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.