Venturing into the majestic Atlas Mountains offers year-round, rewarding, invigorating adventures. Despite the mountains' proximity to the sweltering Sahara Desert, the summer temperatures within the mountainous terrain remain surprisingly moderate. Marrakech's blistering heat at midday, often soaring to 50°C, contrasts with the cool breeze and comfortable 20s°C temperatures you'll find you nestled in the highlands.

Nevertheless, traversing the lower valleys during summer can be a heated affair. Summer nights, though, seldom get cold, save for those spent on the higher peaks, further emphasizing the unique climate of the Atlas Mountains.

Springtime, particularly the latter part, presents the optimal time to visit Imlil, one of the Atlas Mountains' most enchanting destinations. During this season, the winter snow starts melting, the visibility improves markedly compared to the high-summer haze, and daytime temperatures are agreeably mild. The days are warm enough to hike in short sleeves, while a snug sleeping bag would serve well during the cool nights.

As autumn makes its appearance, the atmosphere becomes notably more tranquil. As September draws close, you can anticipate snow flurries gracing the higher peaks. This time of the year also brings abundant ripe fruit in the valleys, a delightful enhancement to your trail snacks.

However, caution is advisable during early winter. The conditions during this period can be challenging – it is often cold, damp, and lacks the advantage of solid snow to tread upon. Conversely, late winter frequently boasts some of the most magnificent days in the Atlas Mountains. The skies are clear, making activities like skiing and sunbathing simultaneously feasible. A cozy duvet might be a comforting companion on less pleasant winter days, with temperatures potentially plunging into the -20s°C.

Indeed, weather conditions in the Atlas Mountains are as varied as unpredictable. Storms can roll in at any time, although they typically telegraph their impending arrival well in advance. By October, rainfall naturally transitions to snowfall on the higher peaks, with temperatures remaining frosty, even during summer, mainly when the wind picks up.

Toubkal, the highest peak in the Atlas Mountains, is infamous for its frosty conditions. Adventurers opting to bivouac here should brace for frost all year round.

Like elsewhere globally, the Atlas Mountains' weather patterns have evolved over recent years. Winter snowfalls have lessened, and heavy snow often arrives in the spring. Additionally, the mountains frequently experience torrential summer storms. Therefore, visitors must remain alert to the dangers of flash floods, always avoiding camping in river beds.

In conclusion, the Atlas Mountains offer an enticing blend of weather conditions and scenic beauty, no matter the season. Each season brings its unique charms and challenges, making every visit to the Atlas an unforgettable experience.