I am becoming convinced that May and June are out of sequence this year. As crazy as 2020 has been thus far, why not?
I reached this conclusion after sunset arrived around 1930 on Monday evening, except there were no stars, and the evening light was a deep blue-green. That’s not a combination that presages fair weather.
A batch of storms had formed over the eastern rampart of the Rocky Mountains in far southern Colorado and northern New Mexico. This is very normal, and is part of the so-called Southwestern Monsoon. However, those storms tend to form a line, running north to south, and stay that way as they sweep out of the mountains and across the High Plains. Regionally, we call it the broom, because it sweeps rain across the land. Since it is a line, severe weather tends to be mitigated and dampened down. That’s June-early July, before the summer doldrums set in (aka a ridge of high pressure that blocks storms and shifts the steering winds.)
May’s storms tend to be more isolated and ferocious. May and June are “severe storm” months. That’s when the combination of cold-front, low pressure, and “dry line” or sharp border between desert air and Gulf of Mexico air makes life . . . sporting. As in “softball-sized hail and eighty MPH winds” sporting. The more isolated storms tend to be stronger, and with the front and low giving them more energy, the storms last well into the night. Oh, and tornadoes tend to come with these systems, caused by the same feature as makes the “Oh that’s just excessive” hail.
There’s also the “popcorn” showers, which bubble up, rain, maybe drop pea-sized or smaller hail if they feel frisky, and then go away.
Monday night’s system produced a massive cluster of storms, and a few monsters that formed ahead of the main batch, then turned at right angles to the cluster. My readers from the rest of the Plains are all saying things along the lines of, “Head for the basement,” or “I hope you had really good crop/auto/roof insurance,” about this time. For those not familiar with Great Plains weather, storms that form ahead of a line/cluster and/or that turn right tend to be very strong and laden with large hail and possibly tornadoes, as well as sending very strong winds ahead of themselves. Monday night skipped the tornadoes, at least as of last I read, but the hail and wind tried to make up for it.
The storm complex consolidated into a very large mass of mess that shifted from southwest to south-by-southwest movement, and developed a crimson bow-echo on the leading edge. This means very, very stout winds racing ahead of the complex, winds that can exceed Cat 1 hurricane speed. Purple* hail-cores marched along behind the bow echo.
Ahead of the storm, the sky turned dark an hour and a bit before official sunset. The light took on a very deep teal-green hue, one of the warning signs of a tall, nasty, hail-rich storm. It wasn’t the green of a day-time hailer, but had more blue to it. I can’t think of the last time I saw that shade in storm light. By this point, the complex had produced tennis-ball sized hail and 80 MPH winds, sending people all over the area diving for cover. Oh, and flooding rains came along, too. A typical May storm mass, in other words, but in late June.
Did I mention I don’t like this sort of heavy weather? And that this made three nights in a row of it? At least it came before midnight. Once the rain and wind began pounding RedQuarters, I relocated from my usual chair under a skylight to someplace less loud. We have skylight shields, but the roar bugs me. The cat followed, and hung around in the quieter part of the house as I finished unpacking from the weekend and then read. At one point I looked out the front windows, and couldn’t see the house kitty-corner from RedQuarters due to the blowing rain. Interestingly, the leading edge of the storm didn’t have all that much thunder or lightning with it. The hail cores seemed to bracket my part of the city, perhaps because of the heat-island effect. Bits of tree and leaves soon littered the yard. I returned to the quiet part of the house and kept reading until the worst rain roar passed and the wind stopped whipping rain around the roof and against my bedroom windows.
RedQuarters got almost two inches in forty-five minutes. The official reporting point on the east edge of town got around a quarter of an inch. This is normal, actually, although sometimes the official total is higher and RedQuarters gets two drips and a spitter. The gutters overflowed with wild abandon, so the next morning Dad Red cleaned out the gutters. The two water troughs filled in the first ten minutes. Both had been completely dry, so that was at least 250 gallons pouring off the roof and out of the gutters.
This is May weather, not late June. *SIGH* I want the broom, not a derecho-like bow-echo or screaming winds, thank you! But we needed the water, and even as fast as that blew/fell, there wasn’t much run-off, based on the debris line in the street the next morning.
*On the National Weather Service and aviation radar, the highest intensity is red. (If you see black in the red, it means run away because the stuff in the air is overloading the radar. This is Not a Good Thing.) Like rock band amps**, the three local TV stations have radar packages that display red plus two, those two being magenta and purple. A purple hail core is generally baseball sized or larger, at least in the clouds.
** This is Spinal Tap joke.