March 2013, so far, is a world apart from March 2012. Roanoke’s high temperature of 47 on Wednesday was 10 degrees cooler than the temperature for March 13 a year ago — 10 degrees cooler than the LOW temperature, that is. For the first 13 days of March 2012, Roanoke’s average temperature was 49.7 degrees … which is almost a degree warmer than the average HIGH temperature so far this March and 8.6 degrees warmer than the average temperature. Roanoke hit 79 for a high on March 13 and then 81 on March 14 in 2012, the first of six days in that warmest March on record with highs 80 or above. Based on the likely upcoming weather pattern, I’m going to venture to say right now that there will be ZERO days 80 or above in March 2013.
The combination of upslope northwesterly wind flow over the mountains, atmospheric disturbances and March sunshine destabilizing the lower layers a little more led to an interesting Wednesday of alternating sunshine and snow squalls. Thursday isn’t likely to be quite a repeat of the vigor of Wednesday’s snow showers, but some may linger, especially into the morning, as high temperatures hang in the 40s in most of Southwest Virginia. Surface wind flow will gradually turn more to the southwest by Friday and Saturday, pushing highs back into the 50s and even possibly the low to mid 60s by Saturday. But a series of disturbances and some uncertainty of where a stationary front may set up, dividing mild and cold air, lead to an unsettled forecast in terms of possible rain showers Saturday through Tuesday. Right now, it doesn’t appear Saturday’s St. Patrick’s Day festivities will be a washout, but some light showers are possible. By early to mid next week, a much stronger storm system will develop in the central U.S. and sweep toward the Great Lakes, dragging a rather strong cold front through, and likely returning us to a colder than normal temperature regime for some days afterward. There are no signals on the horizon for any prolonged warmup periods that would carry us into the 70s for even a few days, but also as of now no signals that suggest prolonged extreme cold, relative to March. Periodic cold fronts with overall normal to below-normal temperatures appear to the likely profile for the remainder of this month. I still wouldn’t entirely rule out some more wintry weather flirtations given the pushes of cold air that are likely to occur intermittently.