Harvard, IL Weather Forecast
McHenry County, Illinois
Seven-day outlook
40–66°F across the weekThe week runs between 41° and 66°, with Tuesday the warmest day of it. There is no real trend across it: one day looks much like the next. Saturday is the wettest day, peaking near 65%.
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 Harvard forecast
Harvard sits at 42.4296°N, 88.6211°W in McHenry 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
- McHenry County
- Coordinates
- 42.4296°N, 88.6211°W
- Population
- 9,356 · 2023 estimate
- Land area
- 8.377 sq mi
Place data from the US Census Bureau. Coordinates are the Census internal point for Harvard, 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 Harvard?
The nearest Doppler radar is KMKX (Milwaukee, WI), 37 miles to the N. 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 Harvard its center is about 2,400 ft above ground. That is comfortably inside the useful range. The lowest scan passes low enough over Harvard to show rotation in the part of a storm where tornadoes actually form. Harvard is closer to its radar than 60% of US cities.
The closest instrument actually measuring the air is KBUU · Burlington Muni on the ASOS/AWOS network, 24 miles away. Far enough that "current conditions" for Harvard 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 Harvard
- Walworth, WI7 mi
- Linn, WI10 mi
- Williams Bay, WI11 mi
- Poplar Grove, IL13 mi
- Woodstock, IL13 mi
- Marengo, IL13 mi
- Delavan, WI14 mi
- Wonder Lake, IL14 mi
Elsewhere in Illinois
ChicagoAuroraJolietNapervilleRockfordElginAll Illinois forecasts →