Kevin Myatt is The Roanoke Times' weather columnist.

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For all you hibernating winter fans dreaming of the perfect weather pattern for an old-fashioned bout of prolonged cold and snow, it finally happened.

In July.

There's been a blocking high pressure system over Greenland, a southward dipping jet stream over the eastern U.S., a persistent upper-level low spinning somewhere near the Great Lakes or Hudson Bay, and strong high pressure over the western United States -- all of which have contributed to drive unusually cool temperatures southward into the central and eastern U.S.

We've had frequent cold frontal passages and strong disturbances diving through the jet stream, sweeping abundant gulf moisture northward. We've even had a few cold-air damming scenarios in which cooler air has been pressed from the northeast against the Appalachians.

If this pattern had dominated a January instead of a July, we would probably have piles of snow after weeks of cold weather, with a few bouts of bitter cold. (I realize that the thought of this sends shivers down the spine of the snow haters out there, many of whom would also prefer a more typical summer than we've had.)

The Upper Midwest, Great Lakes and New England, where some locations will set new standards for the coldest July on record dating to the 1800s, would be frozen solid by this point. And the West -- the Pacific Northwest is in the midst of a triple-digit heat wave currently, with Seattle setting an all-time record high of 103 on Wednesday -- would be wondering where winter went.

We have one day left in July. Warm but not hot temperatures today may nudge averages upward a tenth or two-tenths of a degree, but that won't keep several categories of temperature statistics from ranking July among the coolest on record for Roanoke and Blacksburg.

n Roanoke's average temperature for July through 30 days is 73.3 degrees. That would tie it with July 2000 for the sixth coolest July on record, dating to 1912. Today's forecast highs in the mid-80s could nudge the average to 73.4, tying it for seventh with 1967. The coolest July on record was 71.7 degrees in 1947; the hottest, 80.2 degrees in 1993. Normal for July is considered to be 76.2 degrees.

n Roanoke's average July high temperature of 82.7 is the fifth coolest, a ranking likely to hold today even if the average bumps up a little. The coolest average high temperature for July in Roanoke was set just nine years ago, in 2000, at 81.8 degrees.

n Blacksburg's average temperature of 68.3 degrees through 30 days is tied for the third coolest July with 1979. Blacksburg's weather records begin in 1953. The coolest July on record in Blacksburg was in 1967 at 67.6 degrees; the warmest was in 1993 at 75.9 degrees. July's normal average temperature for Blacksburg is 71.1 degrees.

n Blacksburg's average high temperature through Thursday is 78.2 degrees, which places it third coolest. Like Roanoke, Blacksburg's coolest July for high temperatures was in 2000, when daily maximums averaged 77.6 degrees.

n July also stands, through 5 p.m. Thursday, as the sixth wettest on record in Blacksburg, with 6.25 inches. Just a tenth of an inch of rain today in expected showers and thunderstorms would move it to fifth wettest, and a heavier downpour of an inch or more could raise it even higher in the rankings. Roanoke has had 5.83 inches of rain, nearly 2 inches more than normal for July. Three-quarters of an inch today could move it into the top 10.

There's no clear signal that August is going to begin much differently than what we've seen in July. While some warm, humid periods like we've experienced lately may be in offing, no prolonged hot, dry pattern is on the horizon.

Weather Journal runs Monday, Wednesday and Friday