The house is colder than it should be
You woke up and the thermostat says 62 instead of 68. Maybe the furnace is running and just not keeping up, or maybe it's not running at all. Either way, it's the middle of the night in the Ozarks and the wind is doing that thing where it finds every gap around the windows. This happens a lot around Nixa between December and February, when nights regularly drop into the teens and twenties, sometimes lower when a front comes through off the plains.
Most of the time this isn't a mystery emergency. It's a specific, findable problem, and a good number of them you can at least diagnose yourself before deciding whether to wait until morning or call someone right then.
What the housing stock around here means for this problem
Nixa grew fast, so you've got a mix that matters here: a good chunk of homes built in the 1990s and 2000s with aging original HVAC equipment, plus newer construction out toward the edges of town, plus older farmhouses on bigger lots that have been retrofitted over the decades. A furnace installed when a subdivision went up in the late 90s is now past the point where most manufacturers expect it to run reliably every winter.
Crawl spaces are common in this area rather than full basements, and that matters for cold nights. Pipes and ductwork running through an unconditioned crawl space are exposed to whatever the outside air is doing, which means a no-heat night isn't just uncomfortable, it's also when pipes are most likely to freeze if the system stays down for hours.
More on this from Reading List No Heat Overnight And Who Is Actually At Risk.
Who is actually at risk tonight
Not every no-heat call is equally urgent, and it helps to be honest about where you fall. A healthy adult in a well-insulated newer home with a backup space heater and extra blankets can usually get through to morning uncomfortable but fine. That's a real category and it's most of Nixa on most nights.
The risk goes up fast for a few situations. Infants and older adults lose body heat faster and can't always tell you they're in trouble. Anyone with a heart or respiratory condition is more vulnerable to cold stress than people assume. Homes with exposed or poorly insulated plumbing, especially those crawl-space setups, can go from cold to a burst pipe in a single bad night. And if the outside temperature is in the teens or below and dropping, the math changes regardless of who's in the house, because the home itself starts losing the battle, not just the people in it.
What you can check before deciding to call
Start with the thermostat. Check the batteries if it's battery powered, and confirm it's set to heat, not just a temperature that's being ignored because the mode is wrong. Check the breaker box for the furnace, since a tripped breaker is a five-minute fix and gets mistaken for a dead furnace more often than you'd think.
Look at the furnace filter if you can get to it easily. A filter that's been ignored for months can choke airflow enough that the system shuts itself down as a safety measure. If you have a gas furnace, check whether the pilot light or ignition indicator is on, and check that the gas valve to the house hasn't been shut off for any reason. If you hear the furnace trying to start and then clicking off repeatedly, that's useful information to have ready when you do call someone, but it's not something to keep testing on your own.
Where this stops being a DIY job
Past the five basic checks, this stops being homeowner territory. If you smell gas, leave the house and call the gas company or 911 before you call anyone else. Don't flip switches, don't investigate further. If the furnace runs but blows cold air, or starts and immediately shuts off, or you hear grinding, banging, or a burning smell, that's a sign of a mechanical or electrical fault that needs a trained eye, not troubleshooting at 2 a.m.
If it's genuinely cold outside, below freezing and dropping, and you have a vulnerable person in the house, infant, elderly, or someone with a health condition, that's the point to call for emergency HVAC help overnight rather than waiting until a normal business hour. The cost of getting someone out at night is real, but so is the cost of a frozen pipe or a night spent getting progressively colder with no backup plan. If you don't have a space heater or another safe way to stay warm until help arrives, treat it as urgent and act on it rather than waiting to see if things improve on their own.