Kirby reaches 100° on about 13 days a year, more than 92% of U.S. towns
A typical July afternoon reaches 96°, a January night drops to 41°, and snow is almost unheard of.
A year in Kirby at a glance
Each month’s typical high and low, and what it brings.
What stands out about Kirby’s climate
Compared with towns across the U.S., with Kirby’s place in Texas beside it.
What a year in Kirby feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 277 frost-free days a year
In half of years the last 32° night comes by February 25 and the first by November 28. Frost and day counts come from NOAA’s station at San Antonio Incarnate Word, TX, 5 miles from the town’s center, at about the same height.
The 2023 USDA map puts Kirby’s center in zone 9a: the coldest night of a typical winter, averaged over 1991–2020, reaches about 23°. 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 32 inches of rain a year
May is the wettest month and February the driest. Rain falls on about 89 days a year. Snow is rare: about 0.1" in a normal year at San Antonio Incarnate Word, TX, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Kirby
34% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55°: December and January.
Degree days add up how far each day’s average falls below (heating) or rises above (cooling) 65° over a year. NOAA normals at San Antonio Incarnate Word, TX.
Living with Kirby’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
277 frost-free days in zone 9a. The last frost comes by Feb 25 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 28.
Months with highs of 62–84° and lows of 40° or more: January, February, March, April, October, November and December. 0.1 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Kirby from natural hazards, river flooding is the largest share (42%); heat waves, cold waves, winter storms and ice storms together are 13%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Kirby and its neighbors
Every town next door is within a degree of Kirby in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Kirby’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 |
|---|---|---|---|---|
| Kirby, TX | 41° | 96° | 32" | 0.1" |
| Chico, CA | 38° | 96° | 31" | 0.0" |
| Lawton, OK | 29° | 96° | 32" | 1.8" |
| Grants Pass, OR | 34° | 90° | 33" | 0.9" |
| Cayce, SC | 35° | 93° | 46" | 1.2" |
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 Kirby averaged 0.9° warmer than the 1900s. The biggest change is in February (+1.8°).
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 Kirby compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Kirby’s place among Texas’.
Kirby weather by month
Highs, lows and precipitation from NOAA’s grid at Kirby’s center; snow, wet days and snow on the ground from San Antonio Incarnate Word, TX. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 64° | 41° | 2.0" | 0.0" | 8 | 0 | 48° – 58° |
| February | 68° | 45° | 1.8" | 0.0" | 10 | 0 | 49° – 64° |
| March | 74° | 52° | 2.5" | 0.0" | 9 | 0 | 56° – 68° |
| April | 81° | 58° | 2.4" | 0.0" | 6 | 0 | 64° – 76° |
| May | 87° | 66° | 4.0" | 0.0" | 8 | 0 | 72° – 81° |
| June | 93° | 72° | 3.3" | 0.0" | 7 | 0 | 79° – 86° |
| July | 96° | 74° | 2.2" | 0.0" | 7 | 0 | 80° – 88° |
| August | 97° | 74° | 2.4" | 0.0" | 4 | 0 | 81° – 90° |
| September | 91° | 69° | 3.6" | 0.0" | 8 | 0 | 77° – 85° |
| October | 83° | 60° | 3.3" | 0.0" | 8 | 0 | 68° – 77° |
| November | 72° | 50° | 2.3" | 0.0" | 7 | 0 | 56° – 67° |
| December | 65° | 42° | 2.0" | 0.1" | 8 | 0 | 47° – 57° |
| Year | 81° | 58° | 31.6" | 0.1" | 89 | 0 |
How much a month can swing
A normal is an average. February swings the most: from 1991 to 2020 its average ranged from 49° to 64°. June is the most reliable, staying within 8°.
Where Kirby’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 Kirby’s center.
- Snow: San Antonio Incarnate Word, TX.
- Frost, freezing nights, 90° and 100° days, heating and cooling: San Antonio Incarnate Word, TX, 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 Kirby’s climate
What is the weather like in Kirby?
A typical July afternoon reaches 96°, a January night drops to 41°, and snow is almost unheard of. Milder January nights than 90% of U.S. towns; hotter July afternoons than 96% of U.S. towns.
How cold does it get in Kirby in winter?
January nights average 41°. About 22 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 48°.
How much snow does Kirby get?
About 0.1 inches in a normal winter at San Antonio Incarnate Word, TX, so most winters see none.
How hot does it get in Kirby?
July, with a typical high of 96° and a low of 74°. About 112 days a year reach 90° and 13 reach 100° (San Antonio Incarnate Word, TX).
When is the first and last frost in Kirby?
In half of years the last spring frost (32°) comes by February 25 and the first fall frost by November 28, about 277 frost-free days, at San Antonio Incarnate Word, TX.
What growing zone is Kirby in?
Zone 9a on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 23°.
What is the best time of year to visit Kirby?
By one simple rule (highs of 62–84° and lows of 40° or more), January, February, March, April, October, November and December. The rule is ours, not NOAA’s; the month table has the numbers to judge by.
Is Kirby 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 Kirby.
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.