Once the hottest July on record followed the warmest spring on record, which began with the warmest March on record that came after the second warmest winter on record, I presumed that 2012 would easily march into history as the hottest year in Roanoke’s 101-year recorded weather history. Through three-quarters of the year, with an average of 63 degrees, it is outpacing 1921 and 1930 by seven-tenths of a degree for warmest January-September period on record — that’s a large margin for 9-month average temperature. But June, August and September averaging near normal have slowed the year’s run of heat, and October has opened more than 2 degrees below normal, nearly half over. The temperature will need to average 1.3 degrees above normal over the last 3 months for 2012 to become the hottest year in Roanoke’s weather history, based on average temperature. With October likely sandbagging that pace, there will be no easy march into history for 2012 — I’m leaning toward it not supplanting the 59.6 degrees of 1931 for the record.
Sunday looks to be another picture-perfect October day, starting chilly again (upper 30s-low 40s mostly, some colder spots), then warming a bit more than Saturday (low-mid 70s, rather than Saturday’s low-mid 60s). But the next in the parade of cold fronts arrives late Sunday into early Monday, and this one looks to have just a bit more of a push with it, and will grab more moisture than we’ve seen in the last couple of fronts. Because the front will be fast-moving, and the main low-pressure system will head toward the Great Lakes, we won’t see a lot of rain over a long period of time, but rather a quick burst of some showers and possibly thunderstorms on Monday. Rainfall amounts are not projected to be that much, a quarter inch or less in most locations (second lightest green shade in Hydrometeorological Prediction Center rainfall map inset at left), but this will not be a totally dry front like we’ve become accustomed to lately. Once this front blows by, we get a renewal of the classic October weather, with chilly mornings (maybe some frost/freeze threats again by Wednesday morning) and mild to warm afternoons, with dry weather until the next front and low-pressure system affect us late in the week.