Photo: Crawford, J. G. -- Photographer · Public domainWaterloo has milder winter nights than 81% of U.S. towns
On a normal July day the thermometer tops out near 82°. December is the wettest month here, with about 18 times the rain of July. Its July afternoons stay fresher than in 79% of U.S. towns. Tender plants can go out after about March 14; in half of years the first frost comes by November 18.
A year in Waterloo at a glance
Each month’s typical high and low, and what it brings.
What stands out about Waterloo’s climate
Compared with towns across the U.S., with Waterloo’s place in Oregon beside it.
What a year in Waterloo feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 248 frost-free days a year
In half of years the last 32° night comes by March 14 and the first by November 18. Frost and day counts come from NOAA’s station at Lebanon, OR, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Waterloo’s center in zone 8b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 18°. 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 48 inches of rain a year
December is the wettest month and July the driest. Rain falls on about 140 days a year. Snow is rare: about 0.0" in a normal year at Waterloo, OR, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Waterloo
89% 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 Lebanon, OR.
Living with Waterloo’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
248 frost-free days in zone 8b. The last frost comes by Mar 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 Nov 18.
Months with highs of 62–84° and lows of 40° or more: May, June, July, August, September and October. 0.0 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Waterloo from natural hazards, river flooding is the largest share (63%); heat waves, cold waves, winter storms and ice storms together are 6%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Waterloo and similar climates
TownRatings has no climate map of the towns around Waterloo yet.
Climates most like Waterloo’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 |
|---|---|---|---|---|
| Waterloo, OR | 35° | 82° | 48" | 0.0" |
| Ben Lomond, CA | 40° | 79° | 43" | 0.0" |
| Kill Devil Hills, NC | 35° | 86° | 50" | 1.1" |
| Centralia, WA | 34° | 78° | 49" | 3.9" |
| Virginia Beach, VA | 32° | 87° | 48" | 3.4" |
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 Waterloo averaged 1.1° warmer than the 1900s. The biggest change is in January (+2.7°).
A smaller shift than in 74% 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 Waterloo compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Waterloo’s place among Oregon’s.
Waterloo weather by month
Highs, lows and precipitation from NOAA’s grid at Waterloo’s center; snow, wet days and snow on the ground from Waterloo, OR. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 48° | 35° | 6.5" | 0.0" | 17 | 0 | 36° – 46° |
| February | 51° | 35° | 5.1" | 0.0" | 15 | 0 | 36° – 49° |
| March | 56° | 37° | 5.6" | 0.0" | 16 | 0 | 43° – 52° |
| April | 61° | 40° | 4.5" | 0.0" | 15 | 0 | 46° – 56° |
| May | 68° | 45° | 3.2" | 0.0" | 12 | 0 | 51° – 61° |
| June | 73° | 49° | 2.1" | 0.0" | 9 | 0 | 57° – 67° |
| July | 82° | 52° | 0.4" | 0.0" | 3 | 0 | 61° – 71° |
| August | 83° | 52° | 0.6" | 0.0" | 3 | 0 | 64° – 72° |
| September | 76° | 48° | 1.8" | 0.0" | 6 | 0 | 59° – 65° |
| October | 64° | 43° | 4.1" | 0.0" | 12 | 0 | 49° – 58° |
| November | 53° | 38° | 6.8" | 0.0" | 16 | 0 | 40° – 50° |
| December | 46° | 35° | 7.7" | 0.0" | 16 | 0 | 36° – 44° |
| Year | 63° | 42° | 48.3" | 0.0" | 140 | 0 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 36° to 49°. September is the most reliable, staying within 6°.
Where Waterloo’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 Waterloo’s center.
- Snow: Waterloo, OR.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Lebanon, OR, 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 Waterloo’s climate
What is the weather like in Waterloo?
A typical July afternoon reaches 82°, a January night drops to 35°, and snow is almost unheard of. Milder January nights than 81% of U.S. towns; cooler July afternoons than 79% of U.S. towns.
How cold does it get in Waterloo in winter?
December nights average 35°. About 39 nights a year reach 32° or below. In the coldest December of the last 30 years the month averaged 36°.
How much snow does Waterloo get?
About 0.0 inches in a normal winter at Waterloo, OR, so most winters see none.
How hot does it get in Waterloo?
July, with a typical high of 82° and a low of 52°. About 30 days a year reach 90° and 5 reach 100° (Lebanon, OR).
When is the first and last frost in Waterloo?
In half of years the last spring frost (32°) comes by March 14 and the first fall frost by November 18, about 248 frost-free days, at Lebanon, OR.
What growing zone is Waterloo in?
Zone 8b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 18°.
What is the best time of year to visit Waterloo?
By one simple rule (highs of 62–84° and lows of 40° or more), May, June, July, August, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Waterloo getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 74% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Waterloo.
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.