If you’re planning for St. Patrick’s Day in Idaho, you’ll probably want to prepare for weather that feels like a tug-of-war between winter and spring. Most years, you’ll see cool to cold temperatures, with highs usually landing somewhere in the 40s or 50s Fahrenheit, and there’s always a decent shot at rain or even a little snow, depending on your location.
Longer daylight hours show up this time of year, but conditions can flip fast, so staying flexible really matters.
In southern cities like Boise, chilly mornings usually give way to slightly warmer afternoons. Eastern and northern spots—places like Idaho Falls and Sandpoint—tend to stay colder and get more snow showers. These differences can shape how people celebrate outdoors, whether that’s watching a parade, hiking, or just joining local events.
It helps to know what to expect, so you can pack the right clothes and plan activities—or even have a backup if the weather turns damp or frosty.
Typical Weather Conditions on St. Patrick’s Day in Idaho
In mid-March, Idaho weather likes to bounce between late winter chill and those first hints of spring. You’ll probably wake up to cool mornings, maybe get a mild afternoon in some areas, and face a real possibility of rain or snow depending on your spot.
Average Temperatures and Precipitation
On St. Patrick’s Day, average daytime highs usually hit the mid-40s °F in northern Idaho and climb to the mid-50s °F in southern cities like Boise. Nights often fall close to freezing, especially up in the mountains.
Rain shows up a lot this time of year. Boise typically gets about 1.2 inches of rain in March, while Sandpoint in the north can see around 2.2 inches. Snow isn’t as common in the lower valleys by mid-March, but mountain towns and eastern Idaho might still pick up a light dusting.
You’ll probably see unsettled weather, with a mix of cloudy skies and the occasional burst of sunshine. Rain showers are more likely than big storms, and snow chances drop off the farther south and west you go.
Common Weather Patterns
March weather in Idaho can’t quite make up its mind. Cold fronts from the north still sweep in with brief snow or sleet, but warmer Pacific air sometimes pushes through, bumping up daytime temperatures.
You might get rain in the valleys and snow in the mountains all on the same day. Cloud cover is pretty common, and those clear blue skies don’t show up as much as they will later in spring.
In Boise, skies are clear or partly clear about 43% of the time in March. Up north in Sandpoint, things are cloudier, with just 32% clear skies on average.
Wind also makes itself known. Eastern Idaho, including Idaho Falls, often feels breezier, with March wind speeds around 9 mph. Boise averages about 7 mph, and winds run lighter in the north.
Weather Variations by Region
Southern Idaho, like Boise and Twin Falls, usually gets off a bit easier. Highs stick to the low to mid-50s °F, and snow’s pretty rare. Rain showers can happen, but they’re not usually heavy.
Eastern Idaho—think Idaho Falls or Pocatello—stays cooler. Highs average in the mid to upper 40s °F, and nights can dip into the 20s °F. Snow’s still possible here, even in mid-March.
Northern Idaho, including Coeur d’Alene and Sandpoint, is wetter and cloudier. Highs reach the upper 40s °F, but frequent rain or snow showers make it feel colder. This area also has more days with precipitation than the south.
If you’re planning to celebrate outside, you’ll want to prepare for cool, damp conditions across most of Idaho, with the best chance of lingering snow in the north and east.
Historical Weather Data for St. Patrick’s Day
St. Patrick’s Day weather in Idaho has swung all over the place over the years. Some years, you’ll get mild, almost springlike days, and others hit you with cold, snowy weather. Temperature swings, shifting precipitation, and the occasional storm have all made their mark.
Temperature Records and Extremes
Idaho’s March climate changes fast, and St. Patrick’s Day definitely shows that off. In lower spots like Boise, average highs usually reach the upper 40s to mid-50s °F, with lows dropping into the 30s °F. Mountain towns like McCall or Stanley run colder, with highs in the 30s °F and lows down in the teens.
Sometimes, unseasonably warm years push highs into the 60s °F in the Treasure Valley, making the holiday feel pretty mild. Other years, cold hangs around and keeps highs below freezing in central and eastern Idaho. Late-season cold snaps can even send overnight lows into the single digits in the high country.
You might get anything from jacket weather to a real winter chill, depending on your location.
Precipitation Trends
March always feels like a transition in Idaho, and what you get on St. Patrick’s Day often comes down to elevation. Valleys like Boise or Twin Falls see light rain or a rain-snow mix. Up in the mountains, snowfall is more common, with several inches possible if a storm rolls through.
Long-term records show southern valleys often stay dry, but central and northern mountains see wetter conditions. Snow depth can still be impressive in places like Sun Valley or Coeur d’Alene, especially if winter left a strong snowpack.
Precipitation usually comes scattered, not widespread, but storms can still bring quick changes to travel plans.
Notable Weather Events
Some years, St. Patrick’s Day weather in Idaho has really stood out. In Boise, a warm spell in the 1990s brought highs near 70 °F—pretty wild for mid-March. Over in eastern Idaho, snowstorms have landed on the holiday, dropping several inches and making a mess of parades and events.
Mountain towns sometimes get lucky, with heavy snow on March 17 making for excellent skiing. Past storms in the Sawtooth and Bitterroot ranges have left fresh powder, drawing in spring break visitors.
Other years just coast by quietly, with dry air and clear skies letting everyone celebrate outdoors. Weather really keeps you guessing, so checking the forecast before making plans is a must.
Regional Differences Across Idaho
Weather in mid-March definitely depends on your spot in Idaho. Elevation, latitude, and local geography shape temperatures, precipitation, and how much snow you’ll still see.
Boise and Treasure Valley
In Boise and the Treasure Valley, daytime highs in mid-March usually reach the mid-50s°F, while nights drop into the mid-30s°F. You’ll get a mix of cloudy and partly sunny days, and light rain is more common than snow by now.
Snowfall is rare in the valley during St. Patrick’s week, though you might spot some in the foothills. Average March precipitation is about 1.2 inches, but it tends to come as brief showers.
Winds usually stay light to moderate, around 7 mph, which can make afternoons feel chillier than you expect. The growing season hasn’t started yet, but you’ll see grass greening up and trees starting to bud at lower elevations.
Mountain Areas and Northern Idaho
Higher elevations and northern towns like Sandpoint stay much colder in March. Daytime highs average in the upper 40s°F, and nighttime lows hover near 30°F. Snow still plays a role, with northern Idaho picking up 2 inches or more in March.
Rain and snow often mix, depending on the time of day. Precipitation is frequent, with about 10 days of measurable rain or snow during the month.
Mountain passes can still have icy roads, so travel takes some caution. Daylight lasts close to 12 hours, but the sun sits low, keeping mornings and evenings chilly.
If you’re heading outside, ski resorts are still open, and trails at higher elevations usually stay snow-covered.
Eastern and Southern Idaho
In places like Idaho Falls and Pocatello, March weather stays colder than in Boise. Highs average in the mid-40s°F to upper 40s°F, and lows often hit the mid-20s°F. Snow is still common, averaging around 1 inch for the month, though some years bring more.
Rainfall is limited, usually under 1 inch, but the area sees about 5 to 6 days of precipitation. Winds blow stronger here than in other regions, averaging 8–9 mph, and that makes conditions feel colder.
Spring arrives later here. Fields and open spaces often look brown, and frost is still common at night. If you’re traveling, pack layers that can handle both cold mornings and milder afternoons.
How Weather Impacts St. Patrick’s Day Celebrations
Idaho’s early spring weather likes to surprise you, and that definitely affects how you plan and enjoy St. Patrick’s Day. Cold mornings, wet roads, and the chance of late-season snow or rain can all shape your experience.
Outdoor Event Planning
If you’re going to parades, festivals, or any outdoor gatherings, expect temperatures to start in the 30s and maybe climb to the 50s by afternoon. The weather might swing from sunny to rainy, and some years, snow showers still pop up.
Layered clothing is your best bet—it lets you adjust as the day goes on. Waterproof jackets and sturdy shoes come in handy if the ground’s muddy or wet.
Event organizers sometimes tweak plans based on the forecast. Parades may shorten their routes or change start times if wind or rain picks up. Checking the weather before you head out just makes sense.
Travel Considerations
Driving in Idaho can get tricky in mid-March. Roads may look clear in town but turn slick in higher elevations or shaded spots. If you’re heading to Boise, Coeur d’Alene, or any mountain towns for St. Patrick’s Day, give yourself extra time.
Snow or rain showers can cut visibility, especially after dark. Wind gusts can also make highway driving tougher. Keeping an emergency kit—blankets, water, a flashlight—in your car is just smart in case you get stuck.
Public transit and rideshare options might run on limited schedules, so planning ahead helps if you don’t want to drive. Parking near busy parades or festivals can be tight, especially when wet weather takes away some spaces.
Safety Tips for Variable Conditions
Since Idaho weather can flip between dry, wet, and icy in just a few hours, you’ll want to take simple steps to stay safe. Wear shoes with good grip for wet sidewalks or icy patches.
If you’re planning to drink, arrange a safe ride home ahead of time. Cold air can make alcohol’s effects stronger, so pace yourself and drink some water too.
If you’ve got kids with you, dress them in layers and bring extra gloves or hats. Even if the afternoon feels mild, evenings cool off quickly. Prepping for these changes means you’re less likely to run into weather-related problems during your St. Patrick’s Day fun.
What to Wear and Pack for St. Patrick’s Day in Idaho
Idaho’s mid-March weather loves to change fast—chilly mornings, maybe a mild afternoon, and then a cool evening again. You’ll want clothes that layer well and gear that keeps you comfortable, whether you’re inside at an event or outside at a parade.
Clothing Recommendations
In Idaho, St. Patrick’s Day usually starts chilly, with morning temps in the 40s°F. By afternoon, it often warms up into the 50s or low 60s°F. Nights? They can easily dip back into the 30s.
Honestly, layers are your best friend. Start with a light long-sleeve shirt.
Throw on a medium-weight sweater or fleece, then top it off with a jacket that blocks wind and light rain. If you’re heading to outdoor parades or festivals, a waterproof shell can save you from a soggy afternoon.
Jeans or casual pants are usually just right for bottoms. If you’ll be outside a lot, try thermal leggings under your pants for extra warmth.
Don’t forget comfortable walking shoes or boots with solid traction. Sidewalks and streets sometimes stay damp or slushy from lingering winter weather.
Want to stay festive? Add something green—maybe a scarf, a hat, or a shirt. Gloves and a knit hat still come in handy, especially early or late in the day when it’s coldest.
Essential Gear for Changing Weather
Spring in Idaho loves to keep you guessing. Packing a few smart items makes life easier. A compact umbrella or a lightweight rain jacket helps if a shower sneaks up on you.
Bring sunglasses and sunscreen too. The sun feels stronger at higher elevations, and leftover snow can bounce the rays right back at you.
If you’re hitting outdoor events, carry a small daypack. You’ll want somewhere to stash layers as the day warms up.
A reusable water bottle helps more than you’d expect—dry mountain air can dehydrate you quickly.
For shoes, waterproof boots or shoes keep your feet warm and dry. In Boise, comfy sneakers might work, but up in McCall or Sandpoint, waterproof boots just make sense.
Pack a light pair of gloves and a hat. They barely take up space, but they can really boost your comfort when things cool off.
Tips for Enjoying St. Patrick’s Day Activities in Idaho’s Weather
Idaho’s mid-March weather can be all over the place, so a little planning goes a long way. Indoor events give you a warm break, while outdoor parades, runs, and festivals mean you’ll need extra layers and weather-ready gear.
Best Places to Celebrate
Boise really goes all out for St. Patrick’s Day. You’ll find pub crawls downtown, family-friendly stuff like the YMCA run at Julia Davis Park, and plenty of live music, comedy, and Irish-themed dinners at local pubs and breweries.
Up north, Coeur d’Alene and Sandpoint throw parades with bagpipes and floats. These happen outside, so you’ll want layers and a waterproof jacket if the weather turns.
Smaller cities like Idaho Falls and McCall get into the spirit too, with gatherings at local taverns and breweries. These places feel a bit cozier, which sounds pretty nice if the weather gets cold.
Quick tip: Check forecast updates before you go out. March weather can swing from sunny to snowy fast, especially up in the mountains.
Seasonal Outdoor Activities
If you’re looking to enjoy Idaho’s outdoors around St. Patrick’s Day, you’ll want to prepare for all sorts of weather. In the Treasure Valley, daytime highs usually hit the 40s or 50s °F, so it feels pretty good for walking tours, parades, or maybe hanging out on a brewery patio.
But once the sun goes down, the temperature drops fast. Don’t forget a warm coat.
Up in the mountains, spots like McCall or Sun Valley still get plenty of snow. People love skiing, snowshoeing, or even sledding if you’re into that winter vibe.
The roads can get icy, so give yourself extra travel time, and definitely bring the right gear.
Runners in Boise often join St. Patrick’s Day-themed races, rain or shine. Throw on some moisture-wicking layers, maybe grab gloves or a hat, and you’ll feel a lot better at the starting line.
Checklist for outdoor comfort:
- Waterproof jacket
- Warm base layers
- Gloves and hat
- Sturdy shoes or boots