Photo: Usroadman · CC BY 3.0More precipitation falls on Thornwood than on 77% of U.S. towns: 48 inches a year
The warmest part of a July day comes in at 85° on average. December has warmed most since 1901–2000, part of a 2.2° rise. Warm coats and heating bills mark the months from November to March, when means dip under 50°.
A year in Thornwood at a glance
Each month’s typical high and low, and what it brings.
What stands out about Thornwood’s climate
Compared with towns across the U.S., with Thornwood’s place in New York beside it.
What a year in Thornwood feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 200 frost-free days a year
In half of years the last 32° night comes by April 12 and the first by October 31. Frost and day counts come from NOAA’s station at Westchester Co Airport, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Thornwood’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 33 inches of snow a winter
Snow, measured at Dobbs Ferry-ardsley, NY, falls mostly in February. Precipitation (rain plus melted snow) adds up to 48 inches a year; July is the wettest month and February the driest. Rain or snow falls on about 124 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Thornwood
87% 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 Westchester Co Airport.
Living with Thornwood’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
200 frost-free days in zone 7a. The last frost comes by Apr 12 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 31.
Months with highs of 62–84° and lows of 40° or more: May, June, August, September and October. 0.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Thornwood from natural hazards, river flooding is the largest share (69%); heat waves, cold waves, winter storms and ice storms together are 8%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Thornwood and similar climates
TownRatings has no climate map of the towns around Thornwood yet.
Climates most like Thornwood’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 |
|---|---|---|---|---|
| Thornwood, NY | 22° | 85° | 48" | 33" |
| Hampstead, MD | 22° | 85° | 48" | 34" |
| New Freedom, PA | 21° | 84° | 48" | 29" |
| New Martinsville, WV | 22° | 85° | 46" | 27" |
| Abington, MA | 20° | 84° | 51" | 34" |
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 Thornwood averaged 2.2° warmer than the 1900s. The biggest change is in December (+3.7°).
A bigger shift than in 94% 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 Thornwood compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Thornwood’s place among New York’s.
Thornwood weather by month
Highs, lows and precipitation from NOAA’s grid at Thornwood’s center; snow, wet days and snow on the ground from Dobbs Ferry-ardsley, NY. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 38° | 22° | 3.3" | 9.4" | 11 | 13 | 21° – 37° |
| February | 41° | 23° | 2.8" | 10.9" | 9 | 13 | 19° – 38° |
| March | 49° | 30° | 4.0" | 5.8" | 11 | 7 | 33° – 48° |
| April | 61° | 40° | 4.1" | 0.7" | 13 | 0 | 46° – 55° |
| May | 71° | 49° | 3.9" | 0.0" | 12 | 0 | 56° – 65° |
| June | 80° | 59° | 4.5" | 0.0" | 12 | 0 | 66° – 72° |
| July | 85° | 65° | 4.6" | 0.0" | 10 | 0 | 69° – 78° |
| August | 83° | 63° | 4.3" | 0.0" | 9 | 0 | 69° – 77° |
| September | 76° | 56° | 4.6" | 0.0" | 9 | 0 | 63° – 70° |
| October | 64° | 45° | 4.5" | 0.0" | 9 | 0 | 50° – 62° |
| November | 53° | 35° | 3.7" | 0.3" | 10 | 0 | 39° – 49° |
| December | 43° | 27° | 4.0" | 5.6" | 11 | 7 | 28° – 46° |
| Year | 62° | 43° | 48.3" | 32.7" | 124 | 39 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 19° to 38°. June is the most reliable, staying within 6°.
Where Thornwood’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 Thornwood’s center.
- Snow: Dobbs Ferry-ardsley, NY.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Westchester Co Airport, 5 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 Thornwood’s climate
What is the weather like in Thornwood?
A typical July afternoon reaches 85°, a January night drops to 22°, and about 33 inches of snow falls in a normal winter. Colder January nights than 51% of U.S. towns; cooler July afternoons than 54% of U.S. towns.
How cold does it get in Thornwood in winter?
January nights average 22°. About 105 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 21°.
How much snow does Thornwood get?
About 33 inches in a normal winter at Dobbs Ferry-ardsley, NY, most of it in February, with snow on the ground about 39 days a year.
How hot does it get in Thornwood?
July, with a typical high of 85° and a low of 65°. About 10 days a year reach 90° (Westchester Co Airport).
When is the first and last frost in Thornwood?
In half of years the last spring frost (32°) comes by April 12 and the first fall frost by October 31, about 200 frost-free days, at Westchester Co Airport.
What growing zone is Thornwood 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 Thornwood?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Thornwood getting warmer?
Yes: 1991–2020 averaged 2.2° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 94% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Thornwood.
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.