Climate and monthly weather forecast
Idaho, USA

Idaho has diverse climate types, with a predominantly continental flavor in the central and eastern regions (Köppen climate classification Dsa, Dsb). The western portion has a maritime influence (Köppen Cfb, Csb) from the Pacific Ocean. Idaho lies in the Pacific Northwest region of the United States. The state borders with Montana and Wyoming in the east, Utah, and Nevada in the south, Oregon and Washington in the west, and the Canadian province of British Columbia in the north. The variation in topography, altitude, geography, and proximity to the Pacific Ocean influences the climate.

Idaho, the Gem State, is home to rugged mountain ranges, grassy valleys, arid plains, and fertile lowlands. The average elevation is 1520 meters above sea level, with the highest point at 3859 meters at Borah Peak. The landscape is rugged, and the state has one of the largest natural areas in the United States. The Sawtooth Range is prominent, while others such as the Bitterroot Range, White Cloud Mountains, Clearwater Mountains, and stretches of the Rocky Mountains constitute the chiefly mountainous regions. The principal rivers are Snake, Clearwater, and Salmon, while the Snake River Plain in the south has fertile agricultural land. The panhandle and areas north of the Salmon River follow the Pacific Time Zone, while the south lies in the Mountain Time Zone.

The best time to visit Idaho is from mid-April to late October during the spring, summer, and fall seasons. Early spring is cold and often sees snow and ice in the highlands. The melting of snow begins by April and is the period of watching migratory birds on the lakes and rivers. Summer is warm to hot, with many sunny days, even during the period of high precipitation. Summers tend to be cool in the high mountain ranges and witness a large number of visitors. Early autumn has one of the best conditions with sunny days, a colorful landscape, and breezy evenings.

The worst time to visit Idaho, if any, is from December to February when the highlands are under cover of snow and ice. Cold fronts occasionally occur but rarely last more than a week, and temperatures below 0°F (-17.8°C) are rare. Fog is one of the challenges during the winter when the visibility limits to less than one-fourth of a mile. Mountain trails face closures during heavy snowfall, while roads become slippery in icy conditions. Many areas register between 20" (508mm) to 60" (1524mm) of snowfall in the winter season. Contrary to expectations, winter sees a fair number of tourists in Idaho.

Spring in Idaho sees a gradual transition from the cold of winter. As the snow starts melting in April, it breathes life into the state's flora and fauna. The temperatures during this season tend to be moderate, making it a suitable time for outdoor activities and bird-watching. Rainfall can be sporadic, with areas in the west experiencing wetter conditions. Overall, spring in Idaho is marked by growing warmth and rejuvenation.

Idaho's summer months offer warm to hot days. The daytime temperatures can sometimes climb, but it is rare for them to exceed 100°F (37.8°C). A distinctive feature of Idaho's summer is the notable temperature difference between day and night, ensuring cooler nights even on the hottest days. While the eastern parts might see some wetness during summers, the majority of the state remains relatively dry. This season is particularly vibrant in the high mountain ranges, making it a preferred time for tourists.

Early autumn in Idaho is characterized by clear, sunny days and a landscape painted in shades of gold, orange, and red. Temperatures start to drop, but remain comfortable, especially during the day. Evenings can get a tad breezy, adding to the charm of the season. Rainfall distribution varies across the state, but it's the visual spectacle of changing leaves that captures most attention during this time.

Winter ushers in cold temperatures and, in many areas, significant snowfall. It's common for the highlands to be draped in a thick blanket of snow. The mercury rarely drops below 0°F (-17.8°C) for prolonged periods. The western and northern parts of Idaho typically receive more precipitation during winters. Fog becomes a regular sight, especially in colder areas. Despite its challenges, winter also offers picturesque snow-laden landscapes, making it appealing for those who appreciate the beauty of a winter wonderland.

January is the heart of winter in Idaho, and it often stands out as one of the coldest months of the year. The state's diverse topography means weather conditions can vary considerably across regions. The highlands, such as the areas around Borah Peak and the Sawtooth Range, are blanketed in snow, with temperatures frequently dipping to below freezing. Weather in January »

February in Idaho marks the latter phase of winter, and while it maintains the cold signature of January, subtle changes begin to emerge as the state " towards spring. Temperatures generally see a slight increase, yet remain firmly in the winter spectrum. Areas like the Bitterroot Range and Clearwater Mountains, which are snow-draped in January, continue to be enveloped in white but might experience lesser snowfall as compared to the previous month. Weather in February »

March heralds the transition from winter to spring in Idaho, bringing with it gradual warming and the retreat of snow from lower elevations. While winter's grip remains firm in the mountainous regions, lower areas begin to display telltale signs of the forthcoming spring. The mountainous terrains, including the likes of the Sawtooth Range and the Bitterroot Range, remain blanketed in snow. Weather in March »

April in Idaho is a clear nod to spring, showcasing a dramatic transformation in both temperatures and landscapes. As winter recedes, the state starts to warm, with the chill of the past months becoming a distant memory in many areas. The high-altitude regions, such as the Sawtooth and Bitterroot Ranges, while still retaining some snow, see significant melting. Weather in April »

In May, Idaho fully embraces spring with all its vivacity, shedding the last remnants of winter and preparing for the warmth of the approaching summer. The state pulsates with life, and the transformations are evident in both urban and natural landscapes. Mountainous regions, including the likes of the White Cloud Mountains, undergo a significant change. Weather in May »

June is when summer begins to make its presence distinctly felt in Idaho. The state, with its vast terrains and diverse landscapes, experiences a warmth that's both temperate and inviting, marking a distinct shift from the mildness of spring. Elevated regions, such as the Clearwater Mountains, are now mostly devoid of their snow caps, except for the highest peaks. Weather in June »

July in Idaho is the very epitome of summer, characterized by long, sun-drenched days and landscapes that shimmer under a clear blue sky. The warmth of the season permeates every corner of the state, from its bustling urban centers to the serene expanses of its natural wilderness. The mountainous areas, such as the renowned Sawtooth Range, are not just accessible but also vibrantly alive. Weather in July »

August in Idaho continues the state's summer narrative, maintaining a warm embrace while hinting at the impending transition to fall. The sun still reigns supreme, casting its golden hue over towns, cities, and the vast wilderness. Mountain regions, including areas like the Bitterroot Range, still present verdant landscapes, although there's a gradual shift. Weather in August »

September in Idaho marks the graceful dance between the waning days of summer and the onset of fall. It's a month of transition, characterized by milder temperatures, changing foliage, and a shift in the general atmosphere from the lively buzz of summer to the more contemplative aura of autumn. The state's mountainous terrains, including the majestic White Cloud Mountains, begin to showcase a brilliant spectrum of colors. Weather in September »

As Idaho drifts deeper into the heart of autumn, October emerges as a month bathed in a tapestry of rich hues and marked by a perceptible drop in temperatures. It’s a time of transition, where the final vestiges of summer warmth intertwine with the undeniable crispness of approaching winter. The mountainous backdrops, such as the Clearwater Mountains, are now awash with a full palette of autumn colors. Weather in October »

Idaho's November stands as the gateway to winter, characterized by increasingly cooler temperatures, shifting landscapes, and the first substantial snowfall in certain areas. This month, more than any other, bridges the gap between the vibrant autumn and the silent, white winter that awaits. The state's mountain ranges, such as the Sawtooth Range, begin to see the early signs of snow, especially at higher elevations. Weather in November »

In December, Idaho fully embraces the winter season, with landscapes blanketed in snow, temperatures plummeting, and festive spirits soaring. The month is marked by the silent beauty of snow-covered terrains, the shimmer of frozen waters, and the warm glow of festive lights. Idaho's rugged mountain ranges, including landmarks such as the Bitterroot Range, are often cloaked in deep snow. Weather in December »