Union County, Illinois · Jonesboro
Water spreading, a burst pipe, sewage, mold or smoke? Call to be connected with a restoration company that serves Anna, Jonesboro and Cobden. Start the steps below while you wait.
Answered 24/7 by a participating local provider. We're a referral service and don't do the work ourselves. How it works
Start here
Pick the closest match. These steps limit the damage and protect your insurance claim. Skip anything that isn't safe.
Union County averages 19 nights a year at 20°F or colder, mostly December to February, and 35% of its homes predate 1960.
March brings the most downpours to Union County, part of 12.9 heavy-rain days a year. Check the sump first.
35% of homes here predate 1960, when clay and cast iron sewer laterals were standard. Roots and cracks in those lines are a common cause of backups.
In Union County, 3.15 inches fell on the wettest day of the 2015–2024 record. Storms like that, and ice dams in snowy winters, cause most roof leaks.
25% of occupied homes in Union County heat mainly with wood or propane, above the Illinois county median of 16.5%.
With 79 muggy nights a year, mold in Union County can appear within days of a leak. Dry first, then clean.
Local risk profile
With 7,851 homes and around 16,997 residents, Union County is 413 square miles of southern Illinois. The county seat is Jonesboro, and Anna, Cobden and Dongola round out the largest towns. The county's median home was built in 1975.
49/100 Water Damage Risk Index: Elevated Union County ranks 61 of 102 Illinois counties. See the statewide ranking and method.The three factors where Union County ranks highest compared with other Illinois counties.
Union County is milder than most of Illinois, but not mild enough to skip winterizing. It averaged 77 freezing nights a year over 2015–2024, 19 of them at 20°F or colder, cold enough for pipes in outside walls and crawl spaces to freeze. Among 102 Illinois counties that's 95th.
On February 19, 2015 the low fell to about -9°F, and in the stretch ending February 2021 the county went 11 days in a row below freezing. Leaks from split pipes typically appear the day the thaw arrives.
Most freezing nights fall from December to February, peaking in January. Disconnect garden hoses and shut off outdoor spigots before the first hard frost, and keep the heat at 55°F or higher if you'll be away.
On average the first fall freeze arrives around Oct 28 and the last spring freeze around Mar 30.
Heavy rain is a bigger factor here than in most of Illinois. The county gets about 50 inches of rain and melted snow a year, with 12.9 days of an inch or more (6th of 102). Those downpours cluster in March, April and July, when sump pumps and gutters are tested hardest. The wettest day on record brought 3.15 inches on April 30, 2017. Multi-day storms matter most for basements; the wettest three days on record here totaled 6.15 inches (through May 1, 2017).
The temperature crosses 32°F in both directions on roughly 65 days a year. Each cycle melts and refreezes water at roof edges and in foundation cracks, which is how ice dams and basement seepage get started.
Housing
Roughly 59% of the county's housing was built before 1980. That puts Union among the newer housing stocks of Illinois's 102 counties.
Growth since 2000 added 19% of today's homes. In houses that new, the weak points are washing machine hoses, ice maker lines, water heaters and sump pumps rather than the pipes in the walls.
Manufactured and mobile homes make up 14% of the housing here. Water lines in the underbelly depend on intact skirting and working heat tape, and they're usually the first to freeze in a cold snap.
Beyond water
Union County averages 79 warm, muggy nights a year (lows of 65°F or more) and gets the most rain in March. Keep indoor humidity under 60%, as the EPA advises, and dry any leak within 24 to 48 hours; in a humid month a wet basement left alone won't dry by itself.
Mold remediation: what to expectHeating fuel matters for fire risk. In Union County it's 27% utility gas, 47% electric, 20% propane and 5% wood. Wood and propane heat are more common here than the state median. Have chimneys swept and fuel-burning appliances serviced each fall, and keep three feet clear around stoves and space heaters.
Fire and smoke cleanup: first stepsCoverage
Calls connect to restoration companies that work across Union County. The largest communities by population:
Population from ACS 2020-2024 5-year estimates. Townships and unincorporated areas are covered too.
Nearby
Jackson and Williamson get more pipe-freeze nights than Union. Alexander County has the oldest housing nearby, with 70% of homes built before 1980.
By the numbers
| Factor | Union | Illinois median | Rank |
|---|---|---|---|
| Homes built before 1960 | 35% | 38% | 71 of 102 |
| Homes built before 1980 | 59% | 66% | 72 of 102 |
| Homes built 2000 or later | 19% | 15% | 24 of 102 |
| Manufactured or mobile homes | 14% | 5.6% | 17 of 102 |
| Vacant homes | 13% | 11% | 32 of 102 |
| Wood or propane heat | 25% | 17% | 20 of 102 |
| Nights at 20°F or colder | 19/yr | 35/yr | 95 of 102 |
| Days with 1 inch+ of rain | 13/yr | 8.4/yr | 6 of 102 |
| Freeze-thaw days | 65/yr | 81/yr | 96 of 102 |
| Muggy nights (65°F+) | 79/yr | 51/yr | 5 of 102 |
Rank 1 is the highest value. Bars run from the lowest to the highest Illinois county; the tick marks the median; orange means higher water damage risk than the median, green means lower.
Questions
Peak risk months in Union County: freezing from December to February, heavy rain in March, April and July.
Sources: U.S. Census Bureau, ACS 2024 5-year estimates (2020-2024); weather from NOAA nClimGrid-Daily county averages (EpiNOAA), 2015–2024, averaged across the county; county boundaries from Census TIGER. Reviewed 2026-10-21. Methodology