I haven’t chased in a week and it’s not because there haven’t been any storms. Instead when there have been storms worth chasing I’ve had other commitments, and when I’ve had time to chase the storms have been heavy rainers that I didn’t feel like going after. In fact this summer has been rather wet compared to normal.
The chasing drought can be laid at the feet of the jet stream’s northward retreat. Upper level winds over Virginia are very weak in early August meaning little or no available shear. Convection thus becomes a case of “what goes up must come down” as the vertical rain shaft cancels out the updraft. While that can create some pretty unique outflow boundaries and cool shelf clouds it also makes chasing a “dodge ’em” activity. Chasing (or being chased by) squall lines and multicell complexes becomes tiresome and a bit humdrum after a while, especially when every severe thunderstorm warning contains the phrase “60 mph wind gusts” and nothing else.
From now through early fall what little hope arises for longer lasting discrete storms typically comes from tropical remnants. The lower atmosphere helicity (spin) these systems bring with them have contributed to some exciting chases in past years. Thus I have my eye on the tropics and am paying as much attention to National Hurricane Center forecasts as I am Storm Prediction Center outlooks. So far there’s little on the horizon to generate hope but one never knows.
Of course as the jet stream begins to sag southward again I’ll also be watching troughs as they approach the Mid-Atlantic. A strong cold front with some decent wind shear thrown in can still work chasing wonders this time of year. I’ve been known to chase all the way up to Veterans Day given the right setup.