Photo: Vbofficial · Public domainNo extremes in Rio Grande: its weather tracks the middle of U.S. towns
Peak summer warmth arrives in July, with afternoons near 86°. Warming shows here too: 0.9° more than in 1901–2000, led by December. Tender plants can go out after about April 18; in half of years the first frost comes by October 28.
A year in Rio Grande at a glance
Each month’s typical high and low, and what it brings.
What stands out about Rio Grande’s climate
Compared with towns across the U.S., with Rio Grande’s place in Ohio beside it.
What a year in Rio Grande feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 192 frost-free days a year
In half of years the last 32° night comes by April 18 and the first by October 28. Frost and day counts come from NOAA’s station at Gallipolis, OH, 11 miles from the town’s center, 100 ft lower.
The 2023 USDA map puts Rio Grande’s center in zone 6b: the coldest night of a typical winter, averaged over 1991–2020, reaches about −1°. 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 14 inches of snow a winter
Snow, measured at Waterloo, OH, falls mostly in January. Precipitation (rain plus melted snow) adds up to 43 inches a year; July is the wettest month and November the driest. Rain or snow falls on about 147 days a year.
Rain + melted snow by month
Inches of water
Snowfall by month
Inches of snow
Heating and cooling a home in Rio Grande
81% of the work is heating. Months averaging under 55° run from November 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 Gallipolis, OH.
Living with Rio Grande’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
192 frost-free days in zone 6b. The last frost comes by Apr 18 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 28.
Months with highs of 62–84° and lows of 40° or more: April, May, June, September and October.
Parks & trails →Of the yearly building losses FEMA expects in Rio Grande from natural hazards, river flooding is the largest share (67%); heat waves, cold waves, winter storms and ice storms together are 20%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Rio Grande and similar climates
TownRatings has no climate map of the towns around Rio Grande yet.
Climates most like Rio Grande’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 |
|---|---|---|---|---|
| Rio Grande, OH | 24° | 86° | 43" | 14" |
| Waynesboro, VA | 25° | 85° | 43" | 11" |
| Olney, MD | 25° | 86° | 46" | 16" |
| Shelbyville, IN | 21° | 85° | 44" | 15" |
| Millville, NJ | 25° | 87° | 46" | 12" |
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 Rio Grande averaged 0.9° warmer than the 1900s. The biggest change is in December (+2.3°).
A smaller shift than in 82% 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 Rio Grande compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Rio Grande’s place among Ohio’s.
Rio Grande weather by month
Highs, lows and precipitation from NOAA’s grid at Rio Grande’s center; snow, wet days and snow on the ground from Waterloo, OH. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | 30-yr range |
|---|---|---|---|---|---|---|
| January | 41° | 24° | 3.1" | 5.0" | 13 | 24° – 41° |
| February | 45° | 25° | 3.0" | 3.9" | 13 | 22° – 42° |
| March | 54° | 33° | 4.1" | 2.2" | 13 | 38° – 54° |
| April | 67° | 41° | 3.7" | 0.1" | 13 | 48° – 59° |
| May | 75° | 51° | 4.5" | 0.0" | 15 | 57° – 70° |
| June | 83° | 59° | 4.1" | 0.0" | 13 | 67° – 75° |
| July | 86° | 64° | 4.6" | 0.0" | 12 | 70° – 79° |
| August | 85° | 62° | 3.5" | 0.0" | 11 | 70° – 78° |
| September | 79° | 55° | 3.4" | 0.0" | 10 | 64° – 72° |
| October | 68° | 43° | 3.0" | 0.0" | 10 | 52° – 61° |
| November | 55° | 34° | 2.7" | 0.4" | 10 | 38° – 49° |
| December | 45° | 28° | 3.5" | 2.0" | 13 | 26° – 47° |
| Year | 65° | 43° | 43.2" | 13.6" | 147 |
How much a month can swing
A normal is an average. December swings the most: from 1991 to 2020 its average ranged from 26° to 47°. June is the most reliable, staying within 8°.
Where Rio Grande’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 Rio Grande’s center.
- Snow: Waterloo, OH.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Gallipolis, OH, 11 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 Rio Grande’s climate
What is the weather like in Rio Grande?
A typical July afternoon reaches 86°, a January night drops to 24°, and about 14 inches of snow falls in a normal winter. Milder January nights than 58% of U.S. towns; hotter July afternoons than 54% of U.S. towns.
How cold does it get in Rio Grande in winter?
January nights average 24°. About 103 nights a year reach 32° or below and 2 reach 0° or below. In the coldest January of the last 30 years the month averaged 24°.
How much snow does Rio Grande get?
About 14 inches in a normal winter at Waterloo, OH, most of it in January.
How hot does it get in Rio Grande?
July, with a typical high of 86° and a low of 64°. About 32 days a year reach 90° (Gallipolis, OH).
When is the first and last frost in Rio Grande?
In half of years the last spring frost (32°) comes by April 18 and the first fall frost by October 28, about 192 frost-free days, at Gallipolis, OH.
What growing zone is Rio Grande in?
Zone 6b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about −1°.
What is the best time of year to visit Rio Grande?
By one simple rule (highs of 62–84° and lows of 40° or more), April, May, June, September and October. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Rio Grande getting warmer?
Yes: 1991–2020 averaged 0.9° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 82% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Rio Grande.
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.