Kevin Myatt is The Roanoke Times' weather columnist.

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• We got graupel, but not on official record
• Moisture could get caught up in cold blast
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• Sprinkles or flurries possible Tuesday, but maybe something bigger for the weekend?
• For now, it looks like a quiet, mostly mild week ahead for SW Virginia
• Coldest morning of winter so far likely across much of Southwest Virginia; Tuesday precipitation looking doubtful
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From November through February, we had about seven weeks dominated by Arctic air, but nothing close to a widespread, significant snowfall.

Then, during a four-day gap of cold air in an otherwise mild pattern, it happened.

Winter 2008-09 rushed in with a dramatic flourish just when many thought it had strutted its last pitiful hour on the stage.

But winter won't even be a bit player this weekend, as high temperatures are expected to top 70 today through Sunday, and may even make a valiant effort to reach 80 in Roanoke on Saturday. Only a few dirty parking lot icebergs will be left.

A winter that couldn't make it snow much out of the most prolonged cold in five years, and some of the most severe cold in 13 years, hit a narrow window of opportunity this past weekend to dump 4 to 12 inches of snow on most of the Roanoke and New River valleys and points south and east.

The key was a powerhouse upper-level low pressure system, a swirling vortex of extremely cold air, that managed to get south of us rather than north and west like so many other systems have done in all seasons these past three dry years.

The energy in this storm was so great that some people on Sunday experienced thunder, lightning and graupel -- hail-like ice pellets formed when snow is lifted aloft and caked with layers of ice. When you hear thunder with wintry precipitation, it means business.

Two of the three atmospheric pieces conducive for a large winter storm in our region were present this past weekend, but each was unorthodox.

A very dynamic upper-level low pressure system rode along the southern branch of the jet stream. It seems odd to call it the "southern" branch when the system dived from the Dakotas and Nebraska southeastward, but the jet stream was indeed split into two separate branches, and the disturbance rode the southern part of it. The northern branch influenced the system just enough to pull it northward rather than allowing it go harmlessly out to sea.

Also, high pressure set up to the west, allowing a push of cold air into our region and driving the disturbance far enough south to develop a winter storm throughout a large swath of the East. But it wasn't the broad-based high dominating the West Coast that we would more typically see with a winter storm situation here.

The third factor, blocking high pressure in the north Atlantic, was missing entirely. Had that been present, there would have been a better chance of slowing the storm system, driving cold air even more deeply, and possibly developing the storm much stronger, earlier.

Instead of three somewhat disjointed rounds of moderate precipitation from Saturday to early Monday, we might have had one lengthy and continuous round of heavy snow that would have accumulated a foot or more just about everywhere.

But it appeased starved snow lovers, and it kept Roanoke out of the record books for least snowy winter -- even though the official measurement of 3.6 inches was less than most people got across the Roanoke Valley and elsewhere.

Now, sun seekers, you'll get your weekend, one worthy of early May.

But it's not May yet, it's March. Cold weather is likely to return in the next week or two.