The hills and mountains of northern Glendale very rarely have snow, owing to its warmer temperatures during the winter. It may only occur about every five to 10 years. The last time it snowed was February 26, 2011 in which snow accumulation of approximately 3 inches occurred and sleet was present. Frost sometimes occurs at night from late November to early March. Heavy rains and thunderstorms are also common during the winter. The spring brings pleasant weather, with very little rain. The summer is usually fairly warm, with highs from , to the low 100s (40 °C). Summer is usually very dry, but thunderstorms can come from Arizona, bringing high humidity into the area. These rare days cause heat indices over . Fall brings nice weather, but can be gusty due to the Santa Ana winds, blowing in once or twice a year from October to December. Santa Ana winds can reach up to 70 miles per hour, with gusts up to 100 in mountain passes and canyons. Thunderstorms occur very rarely and they are accompanied by gusty winds and hail.