Photo: Larry D. Moore · CC BY 4.0Round Rock reaches 100° on about 21 days a year, more than 95% of U.S. towns
A typical July afternoon reaches 96°, a January night drops to 38°, and snow is almost unheard of.
A year in Round Rock at a glance
Each month’s typical high and low, and what it brings.
What stands out about Round Rock’s climate
Compared with towns across the U.S., with Round Rock’s place in Texas beside it.
What a year in Round Rock feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 259 frost-free days a year
In half of years the last 32° night comes by March 6 and the first by November 24. Frost and day counts come from NOAA’s station at Georgetown Lake, TX, 11 miles from the city’s center point, 120 ft higher.
The 2023 USDA map puts Round Rock’s center in zone 9a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 21°. 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 36 inches of rain a year
May is the wettest month and February the driest. Rain falls on about 63 days a year. Snow is rare: about 0.0" in a normal year at Round Rock 3 Ne, TX, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Round Rock
41% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55° run from December through February.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at Georgetown Lake, TX.
Living with Round Rock’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
259 frost-free days in zone 9a. The last frost comes by Mar 6 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 24.
Months with highs of 62–84° and lows of 40° or more: February, March, April, October and November. 45 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Round Rock from natural hazards, river flooding is the largest share (57%); heat waves, cold waves, winter storms and ice storms together are 21%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Round Rock and its neighbors
Every town next door is within a degree of Round Rock in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Round Rock’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 |
|---|---|---|---|---|
| Round Rock, TX | 38° | 96° | 36" | 0.0" |
| Chico, CA | 38° | 96° | 31" | 0.0" |
| Lone Grove, OK | 31° | 94° | 39" | 2.7" |
| Cayce, SC | 35° | 93° | 46" | 1.2" |
| Dublin, GA | 37° | 93° | 47" | 0.0" |
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value. Snow and frost-free days come from the nearest weather station, so neighbors often share them.
Warmer than it used to be
The last 30 years in Round Rock averaged 1.1° warmer than the 1900s. The biggest change is in February (+2.1°).
A smaller shift than in 68% 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. In a city of 141,000 people, part of the change is the city itself: pavement and buildings hold heat (the urban heat island).
How Round Rock compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Round Rock’s place among Texas’.
Round Rock weather by month
Highs, lows and precipitation from NOAA’s grid at Round Rock’s center; snow, wet days and snow on the ground from Round Rock 3 Ne, TX. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 61° | 38° | 2.5" | 0.0" | 6 | 0 | 45° – 56° |
| February | 65° | 42° | 2.2" | 0.0" | 5 | 0 | 45° – 62° |
| March | 72° | 49° | 2.8" | 0.0" | 6 | 0 | 53° – 67° |
| April | 79° | 55° | 2.8" | 0.0" | 5 | 0 | 62° – 73° |
| May | 86° | 64° | 4.5" | 0.0" | 6 | 0 | 71° – 80° |
| June | 92° | 70° | 3.5" | 0.0" | 6 | 0 | 78° – 85° |
| July | 96° | 73° | 2.3" | 0.0" | 4 | 0 | 80° – 88° |
| August | 97° | 73° | 2.5" | 0.0" | 4 | 0 | 80° – 90° |
| September | 90° | 67° | 3.5" | 0.0" | 5 | 0 | 74° – 85° |
| October | 81° | 57° | 4.1" | 0.0" | 5 | 0 | 66° – 74° |
| November | 70° | 47° | 2.9" | 0.0" | 5 | 0 | 53° – 64° |
| December | 63° | 40° | 2.7" | 0.0" | 6 | 0 | 44° – 55° |
| Year | 79° | 56° | 36.3" | 0.0" | 63 | 0 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 45° to 62°. June is the most reliable, staying within 8°.
Where Round Rock’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 Round Rock’s center.
- Snow: Round Rock 3 Ne, TX (NOAA station in town).
- Frost, freezing nights, 90° and 100° days, heating and cooling: Georgetown Lake, TX, 11 miles from the city’s center point, 120 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 Round Rock’s climate
What is the weather like in Round Rock?
A typical July afternoon reaches 96°, a January night drops to 38°, and snow is almost unheard of. Milder January nights than 85% of U.S. towns; hotter July afternoons than 97% of U.S. towns.
How cold does it get in Round Rock in winter?
January nights average 38°. About 28 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 45°.
How much snow does Round Rock get?
About 0.0 inches in a normal winter at Round Rock 3 Ne, TX, so most winters see none.
How hot does it get in Round Rock?
July, with a typical high of 96° and a low of 73°. About 112 days a year reach 90° and 21 reach 100° (Georgetown Lake, TX).
When is the first and last frost in Round Rock?
In half of years the last spring frost (32°) comes by March 6 and the first fall frost by November 24, about 259 frost-free days, at Georgetown Lake, TX.
What growing zone is Round Rock in?
Zone 9a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 21°.
What is the best time of year to visit Round Rock?
By one simple rule (highs of 62–84° and lows of 40° or more), February, March, April, October and November. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Round Rock getting warmer?
Yes: 1991–2020 averaged 1.1° warmer than 1901–2000 on NOAA’s grid. A smaller shift than 68% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Round Rock.
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.