NOAA said low pressure over the gulf and high pressure over eastern Russia and northern Alaska drove Arctic air southeast, creating cloud streets as cold, dry air crossed warmer water.
Meteorologist Matthew Cappucci said the polar low brought tropical storm-force winds, snow and thunderstorms, capping a persistently cold, stormy March before wetter late-April weather approached Southcentral and Southeast Alaska.
Is Alaska's historic freeze amidst global warming a stark preview of future climate instability for other regions?
After Alaska's coldest winter in 50 years, is the real danger the impending threat of catastrophic spring floods?
How will the rapid shift from a record freeze to a strong El Niño affect Alaska's crucial fishing and tourism industries?