Sienna, TX climate
Sienna has warm winters and hot summers, with plenty of rain. A typical July afternoon reaches 93°, a January night drops to 44°, and snow is almost unheard of.
NOAA 1991-2020 climate normals Updated once a decadeWhat a year in Sienna feels like
Winter
Spring
Summer
Fall
Sienna weather by month
Average highs, lows, rain and snow for every month, from NOAA’s 1991–2020 normals.
| Month | High | Low | Rain + melt | Snow | Wet days | Snow on ground | 30-yr range |
|---|---|---|---|---|---|---|---|
| January | 64° | 44° | 4.1" | 0 | 9 | 0 | 49° – 61° |
| February | 68° | 49° | 2.9" | 0 | 8 | 0 | 49° – 67° |
| March | 74° | 54° | 3.3" | 0 | 7 | 0 | 58° – 71° |
| April | 79° | 60° | 3.9" | 0 | 7 | 0 | 65° – 74° |
| May | 86° | 68° | 5.0" | 0 | 6 | 0 | 73° – 80° |
| June | 91° | 73° | 5.6" | 0 | 8 | 0 | 79° – 85° |
| July | 93° | 75° | 4.2" | 0 | 8 | 0 | 81° – 86° |
| August | 94° | 75° | 4.8" | 0 | 8 | 0 | 80° – 89° |
| September | 90° | 71° | 5.5" | 0 | 8 | 0 | 77° – 84° |
| October | 83° | 61° | 4.9" | 0 | 6 | 0 | 68° – 77° |
| November | 73° | 52° | 4.2" | 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 |
“Wet days” have at least 0.01" of rain or melted snow. “Snow on ground” counts days with 1" or more. The 30-year range is the coldest and warmest that month’s average temperature got between 1991 and 2020.
Rain and snow in Sienna
Sienna gets 52 inches of rain and melted snow a year. June is the wettest month and February the driest. Rain or snow falls on about 87 days a year.
About 297 frost-free days a year
In half of years the last 32° night comes by February 15 and the first one by December 6. That leaves about 297 frost-free days for gardens, longer than 95% of U.S. towns.
Heating and cooling a home in Sienna
Engineers use “degree days” to estimate how hard a furnace or air conditioner works. In Sienna, 31% of that work is heating and 69% is cooling, so air conditioning is the bigger bill.
Degree days measure how far each day’s average temperature falls below or rises above 65°, added up over a year. Source: NOAA station normals.
Sienna and its neighbors
Sienna borders 2 towns with climate data. January nights across them vary by 0.2°. Missouri City has both the coldest January nights (44°) and the hottest July afternoons (93°). Sienna’s January low is 44° and its July high 93°.
Temperatures and rain come from NOAA’s 5 km grid, so each town gets its own value.
How Sienna compares
Compared with every U.S. town and city on TownTapestry, each counted once.
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°). The shift is larger than in 76% of U.S. towns.
Change by month1991–2020 average minus 1901–2000 average, at Sienna’s spot on NOAA’s grid
How much a month can swing
A normal is an average, and real years wander around it. February swings the most: between 1991 and 2020 its average temperature ranged from 49° to 67°. July is the most reliable, staying within 5°.
Common questions about Sienna’s climate
What is the coldest month in Sienna?
January, with a typical high of 64° and a low of 44°.
What is the hottest month in Sienna?
August, with a typical high of 94° and a low of 75°. About 122 days a year reach 90°.
How much snow does Sienna get?
Almost none. A normal year brings 0.1 inches.
When is the first frost in Sienna?
In half of years the first 32° night comes by December 6, and the last spring frost by February 15.
What is the rainiest month in Sienna?
June, with 5.6 inches of rain and melted snow. The year totals 52 inches.
Temperatures and rainfall come from NOAA’s gridded climate normals for Sienna itself (about a 3-mile square). Snow, frost dates and day counts come from NOAA’s weather station at Thompsons 3 Wsw, TX (8 mi) away. Normals are 30-year averages, not a forecast. Source: NOAA NCEI U.S. Climate Normals, 1991–2020 and 1901–2000.