Kevin Myatt is The Roanoke Times' weather columnist.

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Really, an early April freeze isn't all that weird.

This weekend's chill is a big deal mainly because of how warm it was for so long before it arrived. The excessive warmth got things blooming early, so this freeze may do far more damage than it normally would this time of year.

It wasn't quite a freeze in Roanoke on Friday morning, with a low of 35. But many outlying areas fell to 32 or below. Quite likely, there will be a freeze, a hard one, in all of Southwest Virginia by Easter morning, with lows well into the 20s and even some teens.

And though Sunday's morning low in Roanoke may challenge the April 8 record of 25 set in 1990, history proves that freezing temperatures in early April really aren't that unusual.

In the 58 years from 1948 to 2006, the average date for Roanoke's latest freeze -- the last date in the spring when the low temperature is 32 degrees or colder -- is April 12.

It has come as early as March 18 in 1978 and as late as May 11 in 1966.

In case you're wondering, the average earliest freeze date for Roanoke in that 58-year span is Oct. 22. It has been as early as Oct. 1 in 1993 and as late as Nov. 19 in 2002.

Beyond the developed part of the Roanoke Valley, where the "urban heat island" from buildings and concrete retards cooling a little, the dates for first freezes would be earlier and those for last freezes later, sometimes by weeks, depending on elevation. So keep that in mind if you live away from the city.

The dates of the earliest and latest freezes never tell the whole story of a year's cold months. For one thing, they have little or no correlation to any given winter's severity.

The early last freeze date in 1978 followed one of the coldest winters on record, locally and nationally. The late first freeze date in 2002 preceded our coldest, snowiest winter of the last decade.

A last freeze date may mean one isolated spring day when the morning low barely reaches 32, or it may be the last of several dates in a row when temperatures are several degrees below freezing. The former probably wouldn't do a lot of damage, while the latter could absolutely decimate some crops like peaches.

The May 4 last freeze date in 1986 seems impressive, but it's less so when you consider that the low was only 32 and, if it had been just a degree warmer that morning, the last freeze date would have been March 28 instead.

On the flip side, the last freeze date of April 7 in 2002 is fairly typical, but the temperature fell to 33 degrees on May 22.

One degree colder not only would have eclipsed the record late freeze date by 11 days, but it would have skewed averages by adding 45 days to that year's last freeze date. A May 22 freeze in 2002 would have shifted our 10-year average latest freeze five days later.

But as it is, in the past 10 years, the average date of our latest freeze has been about 10 days earlier than the long-term average, and the average date of our earliest freeze in the fall has been about a week later.

The latest freeze has occurred in March just five times since 1948, but four of them have been since 2000.

Line up the suspects: Global warming, local urban-heat-island warming, natural weather pattern anomalies. Any or all could be factors to varying degrees.

But none of that will keep this from being a bone-chilling Easter. Don't even be surprised to see snowflakes in the air this morning.