Havana, IL Weather Forecast
Mason County, Illinois
Seven-day outlook
38–75°F across the weekThe week runs between 47° and 75°, with today the warmest day of it. There is no real trend across it: one day looks much like the next. Tuesday is the wettest day, peaking near 55%. 3 of the 7 days stay dry.
Forecasts come from the National Weather Service's own computer models, and current conditions from the nearest reporting weather station. Both are served through the weather API. A forecast is guidance, not a warning, and anything the Weather Service has actually issued is on the live map.
The written summaries on this page are generated from the forecast data above, not by a meteorologist. Each sentence is a reading of the same numbers you can see, and no forecaster has reviewed them.
About the Havana forecast
Havana sits at 40.2951°N, 90.0578°W in Mason County, Illinois. The forecast above is drawn for that point from the National Weather Service's own computer models: a seven-day outlook, and a finer-grained one covering the next eighteen hours where it reaches, and the radar and alert panels show what the Weather Service has out over the area right now.
- County
- Mason County
- Coordinates
- 40.2951°N, 90.0578°W
- Population
- 2,827 · 2023 estimate
- Land area
- 2.776 sq mi
Place data from the US Census Bureau. Coordinates are the Census internal point for Havana, and the forecast is for that location, not for every address inside the city limits, and a large city can have real weather differences from one side to the other.
How well can the network see Havana?
The nearest Doppler radar is KILX (Lincoln, IL), 39 miles to the ESE. A WSR-88D's lowest routine scan sits half a degree above horizontal, and the earth curves away beneath it, so by the time that beam reaches Havana its center is about 2,600 ft above ground. That is comfortably inside the useful range. The lowest scan passes low enough over Havana to show rotation in the part of a storm where tornadoes actually form. Havana is closer to its radar than 57% of US cities.
The closest instrument actually measuring the air is KPIA · Peoria Intl on the ASOS/AWOS network, 32 miles away. Far enough that "current conditions" for Havana is an educated reading of somewhere else, worth knowing before you plan around a single temperature.
Beam height is the standard 4/3-earth approximation for the 0.5° scan and assumes normal refraction; it is where the center of the beam is, not its edges, and unusual temperature profiles bend it. Radar siting from the NWS WSR-88D network, station positions from the Illinois observing network as of this build.
Forecasts near Havana
- Canton, IL19 mi
- Beardstown, IL28 mi
- Bushnell, IL29 mi
- Rushville, IL29 mi
- Pekin, IL30 mi
- Bartonville, IL32 mi
- Creve Coeur, IL34 mi
- Macomb, IL35 mi
Elsewhere in Illinois
ChicagoAuroraJolietNapervilleRockfordElginAll Illinois forecasts →

