Photo: RM VM · CC BY-SA 4.0Sienna’s winters are milder and less snowy than most of the U.S.
A typical July afternoon reaches 93°, a January night drops to 44°, and snow is almost unheard of.
A year in Sienna at a glance
Each month’s typical high and low, and what it brings.
What stands out about Sienna’s climate
Compared with towns across the U.S., with Sienna’s place in Texas beside it.
What a year in Sienna feels like
Typical highs and lows by season and by month, from NOAA’s 30-year normals.
About 297 frost-free days a year
In half of years the last 32° night comes by February 15 and the first by December 6. Frost and day counts come from NOAA’s station at Thompsons 3 Wsw, TX, 8 miles from the town’s center, at about the same height.
The 2023 USDA map puts Sienna’s center in zone 9b: the coldest night of a typical winter, averaged over 1991–2020, reaches about 27°. 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 53 inches of rain a year
June is the wettest month and February the driest. Rain falls on about 87 days a year. Snow is rare: about 0.1" in a normal year at Thompsons 3 Wsw, TX, so most winters see none.
Rain + melted snow by month
Inches of water
Heating and cooling a home in Sienna
31% of the work is heating, so air conditioning is the bigger bill. Months averaging under 55° run from 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 Thompsons 3 Wsw, TX.
Living with Sienna’s climate
What the numbers mean for a garden, a free afternoon and a bad-weather day.
297 frost-free days in zone 9b. The last frost comes by Feb 15 in half of years, so many gardeners wait a week or two past that to set out tomatoes. The first fall frost comes by Dec 6.
Months with highs of 62–84° and lows of 40° or more: January, February, March, April, October, November and December. 8.9 miles of trails are waiting.
Parks & trails →Of the yearly building losses FEMA expects in Sienna from natural hazards, river flooding is the largest share (41%); heat waves, cold waves, winter storms and ice storms together are 11%. Normals are averages; the hazards page covers the extremes.
Natural hazards →Sienna and its neighbors
Every town next door is within a degree of Sienna in January and July, closer than the 5 km grid can tell apart. Tap a town to see its climate.
Climates most like Sienna’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 |
|---|---|---|---|---|
| Sienna, TX | 44° | 93° | 53" | 0.1" |
| Ocala, FL | 45° | 92° | 52" | 0.0" |
| St. Marys, GA | 43° | 91° | 51" | 0.0" |
| Paradise, CA | 40° | 93° | 57" | 0.1" |
| Headland, AL | 39° | 91° | 56" | 0.1" |
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 Sienna averaged 1.6° warmer than the 1900s. The biggest change is in February (+2.9°).
A bigger shift than in 66% 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 Sienna compares
Against 12,954 U.S. towns of 2,500 or more (one per 5 km climate cell), with Sienna’s place among Texas’.
Sienna weather by month
Highs, lows and precipitation from NOAA’s grid at Sienna’s center; snow, wet days and snow on the ground from Thompsons 3 Wsw, TX. 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 64° | 44° | 4.1" | 0.0" | 9 | 0 | 49° – 61° |
| February | 68° | 49° | 2.9" | 0.0" | 8 | 0 | 49° – 67° |
| March | 74° | 54° | 3.3" | 0.0" | 7 | 0 | 58° – 71° |
| April | 79° | 60° | 3.9" | 0.0" | 7 | 0 | 65° – 74° |
| May | 86° | 68° | 5.0" | 0.0" | 6 | 0 | 73° – 80° |
| June | 91° | 73° | 5.6" | 0.0" | 8 | 0 | 79° – 85° |
| July | 93° | 75° | 4.2" | 0.0" | 8 | 0 | 81° – 86° |
| August | 94° | 75° | 4.8" | 0.0" | 8 | 0 | 80° – 89° |
| September | 90° | 71° | 5.5" | 0.0" | 8 | 0 | 77° – 84° |
| October | 83° | 61° | 4.9" | 0.0" | 6 | 0 | 68° – 77° |
| November | 73° | 52° | 4.2" | 0.0" | 7 | 0 | 57° – 68° |
| December | 66° | 46° | 4.0" | 0.1" | 8 | 0 | 49° – 61° |
| Year | 80° | 61° | 52.5" | 0.1" | 87 | 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 67°. July is the most reliable, staying within 5°.
Where Sienna’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 Sienna’s center.
- Snow: Thompsons 3 Wsw, TX.
- Frost, freezing nights, 90° and 100° days, heating and cooling: Thompsons 3 Wsw, TX, 8 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 Sienna’s climate
What is the weather like in Sienna?
A typical July afternoon reaches 93°, a January night drops to 44°, and snow is almost unheard of. Milder January nights than 93% of U.S. towns; hotter July afternoons than 91% of U.S. towns.
How cold does it get in Sienna in winter?
January nights average 44°. About 9 nights a year reach 32° or below. In the coldest January of the last 30 years the month averaged 49°.
How much snow does Sienna get?
About 0.1 inches in a normal winter at Thompsons 3 Wsw, TX, so most winters see none.
How hot does it get in Sienna?
July, with a typical high of 93° and a low of 75°. About 122 days a year reach 90° and 9 reach 100° (Thompsons 3 Wsw, TX).
When is the first and last frost in Sienna?
In half of years the last spring frost (32°) comes by February 15 and the first fall frost by December 6, about 297 frost-free days, at Thompsons 3 Wsw, TX.
What growing zone is Sienna in?
Zone 9b on the 2023 USDA Plant Hardiness Zone Map: the coldest night of a typical winter reaches about 27°.
What is the best time of year to visit Sienna?
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 Sienna getting warmer?
Yes: 1991–2020 averaged 1.6° warmer than 1901–2000 on NOAA’s grid. A bigger shift than 66% of U.S. towns.
Neighbors talk weather
Gardens, snow, and the best days of the year in Sienna.
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.