by CNN Meteorologist Judson Jones

Extreme weather occurs in spring when Cold Arctic air clashes with moist, warm air in the Gulf.

Blinding snow and temperatures that are 40 degrees below average does not sound like spring in Denver. On the flip side, the 20 degree above average temperature forecast for New York City feels more like early summer.

But the unexpected is what we expect in spring.

It is the greatest transitional season of them all, when cold Arctic air clashes with the rising warm, moist air from the Gulf and dry, warm air from the Desert Southwest.

The drastic change in temperature is a major factor that aides in the development of thunderstorms across what is known as Tornado Alley.

Tuesday, central Oklahoma is under the gun. There's a moderate risk of hail, damaging thunderstorm winds and tornadoes over about 17,000 square miles.

On average April is the second most active month for tornadoes in Oklahoma.  In 2012, 53 tornadoes touched down in April. That's the most tornadoes ever recorded for the month of April. In 2011, the state had 50 total tornadoes for the month of April.

While Oklahoma could still shatter the record breaking trend for tornadoes this month, Denver won’t even get close to touching their April record snowfall of 23” set in 1885.

Meteorologist Melissa Lefevre contributed to this report.