Original analysis of NOAA and Census data
Tucson heat data: how hard summer is on an air conditioner
Tucson now averages 78.9 days a year at 100°F or hotter and 22.5 nights that never cool below 80°F, based on 78 years of daily readings at Tucson International Airport. Both numbers are well above the 1991-2020 averages of 67.9 and 10.8.
Days per year at 100°F or hotter, Tucson International Airport
Nights per year when the low stayed at 80°F or above
What we found
- More 100 degree days. 67.9 a year in 1991-2020, 78.9 in 2016-2025, and 86 a year so far in the 2020s (6 complete years).
- Hot nights doubled. Nights with a low of 80°F or more went from 10.8 a year to 22.5. Nights at 75°F or more went from 46.2 to 63.
- A longer season. Over 2016-2025 the first 100°F day came around May 10 on average and the last around September 27, about 140 days apart. In 1991-2020 it was May 18 to September 25.
- Peak months: June and July each average about 23 days at 100°F or more. August averages 17, and September 10.
- Records: the hottest reading since 1948 was 117°F on June 26, 1990. The longest run of 100°F days was 53 in a row, ending August 7, 2023. The warmest night on record there had a low of 89°F, first on July 22, 2006.
- 2026 so far: 77 days at 100°F or more through October 24, 2026, against a 1991-2020 average of 67.9 by that date. The high for the year was 110°F on August 1, 2026. 27 nights stayed at 80°F or above.
- Monsoon: the three monsoon months, July through September, bring 52% of the airport's average yearly rain (1991-2020), and the humidity that comes with it. That is when swamp coolers lose much of their effect.
Average days at 100°F or hotter, by month
Average daily high and low by month, Tucson International Airport
By decade
| Decade | Days at 100°F+ per year | Days at 110°F+ per year | Nights at 80°F+ per year |
|---|---|---|---|
| 1950s | 51.2 | 0.4 | 3.6 |
| 1960s | 34.2 | 0.1 | 1.9 |
| 1970s | 39.0 | 0.2 | 4.1 |
| 1980s | 58.6 | 1.5 | 3.1 |
| 1990s | 65.1 | 3.6 | 6.3 |
| 2000s | 63.7 | 1.1 | 8.0 |
| 2010s | 69.2 | 2.6 | 15.4 |
| 2020 to 2025 | 86.0 | 8.2 | 26.2 |
Homes by ZIP code
Older housing tends to mean older ducts and systems that were added or replaced piecemeal. Heating fuel shows which homes already rely on electric heat, where a heat pump is the usual replacement.
| ZIP | Area | Housing units | Median year built | Built before 1980 | Built 2000 or later | Owner occupied | Electric heat |
|---|---|---|---|---|---|---|---|
| 85705 | Flowing Wells / Amphi | 29,488 | 1977 | 57% | 16% | 45% | 54% |
| 85710 | Eastside (central) | 28,817 | 1976 | 61% | 13% | 55% | 48% |
| 85719 | University area | 22,463 | 1974 | 63% | 13% | 28% | 57% |
| 85711 | Midtown (east) | 19,903 | 1963 | 76% | 7% | 49% | 42% |
| 85706 | South Tucson / Airport area | 19,276 | 1983 | 45% | 25% | 57% | 55% |
| 85716 | Midtown / Sam Hughes | 19,141 | 1964 | 75% | 6% | 38% | 51% |
| 85713 | Southwest Tucson / Barrio area | 19,096 | 1977 | 56% | 21% | 63% | 41% |
| 85712 | Midtown (north) | 18,290 | 1975 | 62% | 11% | 42% | 53% |
| 85704 | Casas Adobes | 18,148 | 1981 | 47% | 19% | 58% | 49% |
| 85745 | Tucson Mountains / Westside | 17,497 | 1988 | 33% | 26% | 67% | 52% |
| 85614 | Green Valley | 17,143 | 1993 | 36% | 39% | 83% | 42% |
| 85730 | Southeast (east of Davis-Monthan) | 17,137 | 1979 | 53% | 13% | 69% | 38% |
| 85746 | Drexel Heights / Valencia West | 16,008 | 1991 | 24% | 28% | 76% | 36% |
| 85718 | Catalina Foothills (west) | 15,103 | 1983 | 42% | 19% | 69% | 51% |
| 85741 | Casas Adobes (north) | 14,862 | 1986 | 30% | 19% | 64% | 57% |
| 85750 | Catalina Foothills (east) | 13,723 | 1987 | 23% | 14% | 76% | 50% |
| 85743 | Picture Rocks / Marana (west) | 13,086 | 2000 | 9% | 51% | 86% | 31% |
| 85742 | Northwest / Cortaro | 13,003 | 1996 | 8% | 35% | 81% | 41% |
| 85756 | Southeast (south of the airport) | 12,943 | 2001 | 21% | 55% | 81% | 48% |
| 85641 | Vail | 12,033 | 2007 | 4% | 81% | 94% | 34% |
| 85629 | Sahuarita | 10,598 | 2006 | 8% | 81% | 84% | 36% |
| 85737 | Oro Valley | 10,493 | 1996 | 10% | 30% | 76% | 35% |
| 85747 | Rita Ranch / Southeast | 10,286 | 2002 | 3% | 56% | 80% | 30% |
| 85755 | Oro Valley (north) | 9,846 | 2000 | 1% | 51% | 90% | 20% |
| 85739 | Catalina / SaddleBrooke | 9,841 | 2001 | 8% | 52% | 94% | 27% |
| 85715 | Northeast / Sabino Canyon | 9,598 | 1982 | 46% | 14% | 72% | 41% |
| 85748 | Eastside (Houghton) | 8,782 | 1992 | 26% | 24% | 76% | 39% |
| 85749 | Tanque Verde | 8,687 | 1987 | 39% | 21% | 86% | 41% |
| 85653 | Marana | 8,487 | 2006 | 12% | 68% | 85% | 37% |
| 85658 | Marana (Dove Mountain) | 7,748 | 2009 | 3% | 88% | 86% | 32% |
| 85757 | Southwest (Valencia and Ajo Way area) | 6,994 | 2005 | 15% | 69% | 85% | 22% |
| 85714 | South Tucson (south) | 5,729 | 1969 | 73% | 10% | 53% | 55% |
| 85622 | Green Valley (north) | 4,730 | 1990 | 19% | 25% | 89% | 30% |
| 85735 | Tucson Estates / Drexel Heights (west) | 4,575 | 1994 | 25% | 33% | 88% | 45% |
| 85701 | Downtown Tucson | 3,832 | 1956 | 64% | 24% | 26% | 59% |
| 85736 | Three Points / Robles Junction | 1,954 | 1990 | 25% | 24% | 87% | 59% |
Area names are our shorthand for the main neighborhood or town in each ZIP. Census ACS 2020-2024 5-year estimates (tables B25034, B25035, B25003, B25040). Click a column to sort.
How we built this
Temperature. NOAA NCEI Global Historical Climatology Network daily summaries for Tucson International Airport (station USW00023160), June 1, 1946 to October 24, 2026. A year counts only if it has a high and low on at least 355 days, which leaves 78 complete years (1948-2025). "Normal" here means the average of 1991-2020; "recent" means 2016-2025. These are our own counts from the daily record, not NOAA's official normals.
Homes. US Census American Community Survey 2020-2024 5-year estimates by ZIP Code Tabulation Area, via Census Reporter.
Limits. One airport station doesn't describe every neighborhood. Higher ground and the urban core can run cooler or warmer than the airport, especially at night. Use this to understand the area, not to diagnose your system.
Using this data. Journalists and inspectors are welcome to cite or republish these charts and tables with a link to this page (CC BY 4.0).