Idaho's 'springiest' day of the year is May 10

By the time late winter rolls around, a lot of Americans start looking for signs that spring is finally on the way.

The calendar might say it begins in March, but most people know that the real turning point comes later — that first stretch of mild air, longer evenings and trees suddenly filling with leaves again.

Curious about when that moment actually happens around the country, travel company Exoticca looked at when each state tends to experience its most convincingly “spring-like” conditions, the point when the season really starts to feel settled in rather than just beginning.

To work it out, researchers analyzed the average timing of the last spring freeze in different parts of the country, since that’s typically when winter finally stops threatening gardens and new growth.

Because plants usually need a little time after the final frost to properly leaf out, the analysis also included a point three weeks later, when greenery tends to be more noticeably returning.

The midpoint between these two markers was used to estimate each state’s “springiest day” — the point when spring feels most clearly established.

Idaho experienced its last freeze of spring Thursday, April 30. Its greenery return becomes more noticeable around three weeks later, on Thursday, May 21. Based on these combined indicators, the state’s “springiest day” is estimated to fall on Sunday, May 10.

What emerged is a picture of spring slowly climbing its way north across the map. 

Among the warmest parts of the country, the season settles in earlier than the rest. For example, across the Southern states, spring weather tends to peak by mid-March. 

States in the Southeast such as Georgia and Tennessee tend to hit their sweet spot between the end of March and the first days of April, that window when the weather turns comfortably mild and the landscape suddenly looks greener almost overnight.

States farther northeast have to wait a bit longer. In states like Illinois, Massachusetts and New York, the point when spring reliably feels established usually lands sometime in the second half of April or early May. By then, the last frosts have mostly passed and trees begin leafing out in earnest.

In the northern plains and mountain states, winter hangs on longest of all. The Dakotas and Montana reach their “springiest” moment later in May, while Wyoming comes last with a date of May 31, nearly three months after spring has already settled in the earliest states.

Looked at another way, the data shows spring spreading northward across the country in a kind of slow seasonal wave. The equinox may mark the official beginning of the season everywhere at once, but the point when it truly feels like spring arrives gradually over the following weeks.

A spokesperson for Exoticca said the idea was to illustrate how spring doesn’t arrive everywhere at once in the U.S., giving travelers a clearer sense of when each state begins to experience its most classic spring conditions. 

“Spring means something slightly different depending on where you live,” Exoticca Chief Marketing Officer Juanjo Duran said. “In some places, people are enjoying warm sunshine and early blossoms by February, while in others it takes until May before winter really lets go. We thought it would be a good way to encourage people to make the most of that first really perfect spring day when it arrives.”

Read the full blog article: exoticca.com/us/blog/the-springiest-day-of-the-year