If you head out for St. Patrick’s Day in Wisconsin, you just never know what you’ll get. Some years, the sun feels almost warm, but others will hit you with biting cold, snow, or some odd mix of both.
Usually, you’ll see highs in the 40s, lows in the 20s, and there’s about a 40 to 45% chance of some kind of precipitation.
That unpredictability makes planning a bit of a gamble, but honestly, it’s part of the fun. One year you might stroll to a parade in a light jacket, and the next, you’re digging out your heavy winter coat.
Snow on the ground shows up in many parts of the state, especially away from the lakes. It doesn’t always fall right on the holiday, though.
Knowing what typically happens on March 17 helps you get ready for both celebrations and potential travel headaches. If you look at weather history, you’ll find everything from mellow averages to wild extremes, and Wisconsin’s geography just keeps things even more unpredictable.
Typical Weather Conditions on St. Patrick’s Day
March 17 brings a wide range of weather to Wisconsin thanks to its humid continental climate. Temperatures can swing between lingering cold and hints of spring warmth. Wind and cloud cover really depend on whatever pressure systems happen to be rolling through.
Average Temperatures Across Wisconsin
In mid-March, daytime highs usually land in the 40s°F, and lows drop into the 20s°F. Down south in Milwaukee, normal highs hover around 46–50°F, with lows near 30°F.
Northern areas run colder, with highs in the upper 30s to low 40s°F and lows sometimes in the teens or 20s.
Records show that extremes do happen. Sometimes, highs have soared into the 70s and 80s°F during rare warm spells. Other years, the mercury barely crawls out of the teens or 20s.
March can flip from winter to spring and back again in a matter of days.
Snow isn’t super likely, but it’s definitely possible. In parts of western Wisconsin, average snowfall for March 17 sits under 0.5 inches. Still, some years have dumped over 8 inches in a single day.
Rain or a messy mix shows up often, with about a 40–45% chance of measurable precipitation on this date.
Regional Differences: Northern vs. Southern Wisconsin
Northern Wisconsin usually gets cooler temperatures and more chances for snow cover. Towns near Lake Superior can still have several inches of snow on the ground, and morning lows can dip below 10°F.
Travel gets tougher up north if a late-season storm rolls in.
Southern Wisconsin, including Milwaukee and Madison, stays milder. Snow cover is less common, and when it does precipitate, you’re more likely to get rain or a slushy mix.
Highs in the south often run 5–10 degrees warmer than up north, which makes outdoor events a little easier to handle.
Latitude and local geography explain most of the regional difference. Northern spots hang on to winter longer, while southern areas sometimes catch early spring air coming up from the mid-South and central Plains.
Wind and Cloud Cover Patterns
In March, wind speeds generally range between 15–25 mph across Wisconsin. When low-pressure systems swing through, gusts can really pick up and make things blustery.
High pressure tends to calm things down and clear the skies.
Cloud cover jumps around a lot. Overcast days pop up when storm systems track across the Great Lakes or upper Midwest, and these keep daytime temperatures cooler.
When high pressure settles in, you’ll probably see clear skies and maybe a slightly warmer afternoon.
Late winter storms can still barrel through. They might bring blowing snow up north or chilly rain down south.
With all these shifting patterns, it’s smart to prep for brisk winds and changing skies if you’re planning anything outside for St. Patrick’s Day.
Precipitation and Snowfall Trends
Mid-March in Wisconsin often brings a mix of rain and snow. Some years, you’ll get more rain, especially in the south, but other times, winter hangs on with snow on the ground and maybe a fresh dusting.
Rainfall Averages and Frequency
Rain isn’t as common as snow around St. Patrick’s Day, but it happens. Southern Wisconsin gets light rain showers more often if highs creep into the 40s or 50s.
Northern areas, where it stays colder, see fewer rain events.
On average, precipitation totals in mid-March are pretty modest, usually less than half an inch for the day. Even a little rain can make roads slick if it freezes overnight.
Measurable rain only shows up every few years on March 17 in some places. Trace amounts are more common than a real soaker. Thunderstorms and hail almost never happen this time of year, though they’re not totally impossible in the south if warm air pushes in.
Typical Snowfall Amounts
Snow still shows up regularly in Wisconsin during mid-March. Average daily snowfall for St. Patrick’s Day is usually under an inch, but many years see at least a little.
Northern and central parts of the state have a better shot at fresh snow. In the south, snow sometimes mixes with rain or lands as wet, slushy flakes that melt fast.
A light coating is pretty normal, but every so often, a strong late-winter storm drops several inches on March 17. Travel can get dicey, depending on where you are.
Snow Depth and Max Snowfall Records
Snow depth on St. Patrick’s Day really depends on where you are. In northern Wisconsin, you might still find 5–15 inches on the ground, while the south sometimes has barely any.
Records show that maximum snowfall for the date can top half a foot in some spots. Milwaukee and Madison, with weather records going back to the 1800s, have both seen big snowfalls on March 17, though it’s rare.
Snow sticks around longer in shady or rural spots, while cities lose their cover faster thanks to pavement and warmer microclimates.
If you’re planning outdoor activities, it’s worth knowing that a spot just 50 miles away might look completely different in terms of snow cover.
Notable Weather Events and Extremes
St. Patrick’s Day in Wisconsin has thrown all sorts of weather at people—heavy snow, blizzards, strong winds, and the occasional early spring thunderstorm.
Averages might point to cool and damp, but history shows the holiday can swing to dangerous storms or record-breaking extremes.
Severe Thunderstorms and Hail
March is usually too cold for a bunch of thunderstorms, but sometimes the holiday lines up with severe outbreaks across the central U.S.
Strong storm systems rolling out of the southern Plains—think western Kansas, northwest Oklahoma, and the Texas Panhandle—occasionally track northeast and mess with Wisconsin’s weather.
On rare days, these systems have brought severe thunderstorms and hail to southern Wisconsin. Hailstones have been big enough to ding up cars, break windows, and mess with any early farm equipment sitting outside.
Even smaller storms can produce damaging hail in March, since cold air aloft lets ice form quickly.
Damaging Gusts and Wind Advisories
High winds are more likely than thunderstorms in mid-March. Strong low-pressure systems moving over the Upper Midwest can whip up damaging gusts across Wisconsin.
Wind advisories go out when sustained winds hit 25–35 mph and gusts top 45 mph.
Some years, wind speeds on St. Patrick’s Day have blown past 50 mph in open country and along river valleys. These gusts can snap tree branches, knock down power lines, and make driving tough—especially for trucks and high-profile vehicles.
Back in 1965, a major storm hit Wisconsin with blizzard conditions. Winds and heavy snow piled up drifts several feet high, shutting down roads and stranding people.
It’s a good reminder that March winds can turn an ordinary storm into a real headache.
Historic St. Patrick’s Day Weather Records
Wisconsin has seen some wild weather swings on March 17. In La Crosse, the warmest St. Patrick’s Day hit 83°F in 2012. The coldest high was just 10°F in 1941. That same day, the low plunged to -7°F.
Snowfall records are just as dramatic. La Crosse got 8.4 inches on March 17, 1965, during the blizzard that also buried Minnesota. Snow depths have topped 20 inches in mid-March, making travel close to impossible.
Even the rain records are impressive. In 1966, La Crosse picked up just over 1 inch of rain on St. Patrick’s Day, which is a lot for that time of year.
You really never know what you’ll get.
Impact of Lakes and Local Geography
Wisconsin’s mid-March weather doesn’t just depend on the calendar. Nearby lakes and the difference between urban and rural landscapes play a huge role.
These factors change how cold it feels, how much snow falls, and how long it sticks around.
Lake Effect Snow and Temperature Moderation
Big lakes, especially Lake Michigan, shape the climate of eastern Wisconsin. When cold air sweeps over the lake, it can grab moisture and drop extra snow onshore. This lake effect snow happens more earlier in winter but can still show up in March.
Cities like Milwaukee or Sheboygan sometimes see heavier snowfall than inland towns. Even in mid-March, the lake can add a few surprise inches if conditions line up.
Lakes also help keep temperatures in check. Areas near Lake Michigan stay a little warmer at night in March than places like La Crosse or Eau Claire.
This effect means less risk of bitter cold, but sometimes it keeps daytime highs a bit cooler than farther west.
| Location | Average High (°F) | Average Low (°F) | Lake Influence |
|---|---|---|---|
| Milwaukee (Lake MI) | ~43 | ~29 | Moderated temps, occasional lake snow |
| La Crosse (inland) | ~46 | ~27 | Larger swings, less lake effect snow |
Urban vs. Rural Weather Patterns
Cities in Wisconsin, like Madison or Milwaukee, get what’s called the urban heat island effect. Buildings and pavement soak up and hold heat, so city centers run a bit warmer than the countryside.
Around St. Patrick’s Day, this means snow melts faster in cities.
Rural areas, especially in the west and north, cool off more quickly at night. That usually means colder mornings and a better shot at frost.
Snow sticks around longer in these spots, since open fields and forests reflect more sunlight and don’t hold warmth like cities do.
Wind exposure changes things, too. Open rural land lets winds really rip, which can crank up wind chill and cause drifting snow.
In cities, buildings block and redirect winds, so conditions can feel less harsh—or just unpredictable from one street to the next.
If you’re traveling, expect rural highways to stay icy longer after storms. City roads usually clear up faster because of more traffic and frequent treatment.
That’s something to keep in mind if you’re driving between regions around St. Patrick’s Day.
Weather Forecasting and Preparation
Mid-March weather in Wisconsin can flip fast between mild, wet, and snowy. If you know how to find reliable forecasts and get ready for changing conditions, you’ll have a much better time and stay safer.
How to Check the Latest St. Patrick’s Day Forecast
Start by checking the National Weather Service (NWS) or a trusted local station. These sources update several times a day, offering details like temperature, wind speed, precipitation, and timing.
If you’re planning to attend a parade or any outdoor gathering, grab an hourly forecast. Hourly updates give you a better sense of when things might shift.
It’s smart to compare a few sources. For example:
| Source | Strengths |
|---|---|
| NWS | Official, most detailed local warnings |
| Local TV/Radio | Quick updates, community focus |
| Mobile Apps | Real-time alerts, radar access |
Check the forecast the night before and again the morning of March 17. That way, you catch any last-minute changes.
Advice for Staying Safe and Comfortable
Weather on St. Patrick’s Day swings from chilly mornings to breezy afternoons. Dress in layers so you can adjust as the day goes on. If rain or snow is possible, waterproof outerwear helps a lot.
If you’re walking in a parade or spending time outside, wear sturdy shoes with good grip. Sidewalks and streets might be wet, icy, or just plain slushy.
Watch out for wind speeds. March winds can make it feel much colder. Carrying hand warmers or a hat that covers your ears can really help.
If you’re driving, be ready for slick spots. Even a little snow or freezing drizzle can surprise you. Give yourself extra travel time, and keep an emergency kit in your car just in case.
Role of the Weather Forecast Office
The Weather Forecast Office (WFO) in Wisconsin keeps you in the loop. Meteorologists there watch radar, satellite feeds, and computer models to create daily forecasts and warnings.
They issue hazardous weather outlooks for risks like snow, freezing rain, or strong winds. These updates matter a lot in March, when things can change fast.
WFOs work with local governments, schools, and event organizers. If there’s a parade coming up, officials often call the forecast office for advice on timing and safety.
You can get their info straight from the NWS website, NOAA Weather Radio, or mobile alerts. That way, you get official updates, not just general news.
Outdoor Activities and Seasonal Considerations
Wisconsin weather in mid-March can flip from cold and snowy to mild and damp. Outdoor plans depend on both what’s been happening and what’s typical for the season, so some activities just make more sense than others.
Hiking and Exploring Nature
Trails in Wisconsin usually stay snow-covered or muddy this time of year. Up north, you might still see several inches of snowpack, while the south might have bare ground with icy patches. Wear waterproof boots and dress in layers—mornings can dip below freezing, but afternoons sometimes hit the 40s.
Short hikes in places like Devil’s Lake or Kettle Moraine work if you’re ready for slippery spots. Trekking poles can help you keep your balance on icy hills. Some trails might be closed if the ground’s thawing, so check park advisories before you go.
Wildlife starts to wake up as the season shifts. You might spot migrating birds or deer foraging in open fields. If you’re into that, bring binoculars and look for early signs of spring.
Swimming, Boating, and Other Water Activities
Swimming’s really not a good idea in March—lake and river water is still near freezing. Hypothermia can happen fast, even if the air feels okay. Most beaches and swimming spots stay closed until late spring anyway.
Boating gets possible on some rivers and lakes once the ice starts breaking up, but it’s a bit unpredictable. Ice can hang on in shady spots, and snowmelt can make currents run faster. If you head out, use a sturdy boat, wear a life jacket, and skip the small or wobbly crafts.
Fishing from shore or piers is a safer bet. Early spring is actually great for walleye runs in rivers like the Wolf and Fox. Always check local ice reports before fishing on frozen lakes, since late-season ice can get thin and risky.
Planning Events and Parades
St. Patrick’s Day parades and outdoor gatherings in Wisconsin? Yeah, they usually mean braving some pretty chilly weather. Highs in March might hit the 30s or 40s, but honestly, the wind and damp ground often make it feel colder than the thermometer says.
It’s smart to remind everyone—spectators and parade folks alike—to bundle up with warm layers, gloves, and hats. Nobody wants to shiver through the festivities.
Organizers usually come up with backup plans in case snow or rain shows up. Temporary shelters, heated tents, or moving things indoors can really save the day if the weather turns nasty.
Melting snow sometimes leaves the streets wet, so parade floats and marching bands have to watch their step. Slippery spots can sneak up on you.
Still, lots of Wisconsin towns keep the tradition going, no matter the forecast. Milwaukee, Madison, and plenty of smaller places throw parades that pull in big crowds.
If you decide to go, be ready for anything underfoot—one block might be slushy, the next totally clear. It all depends on what the weather’s been up to lately.