Winter to the west, summer to the east…dangerous day in the middle.
We’ve been tracking the weather system moving into the Plains today since last week when it was battering the West Coast. Over the last 10 days this cold front has been the boundary between winter (four feet of snow this past weekend in California’s Sierras) and spring — scratch that — between winter and summer (look no further than the hundreds of new record high temperatures over the past week and the mid-June conditions in places like Minnesota and Ohio). Today heralds the next phase of this system.
As is typical this time of year, heat and humidity are abundant across the Plains, as well as in areas such as the South and the Midwest — although not usually to this degree (literally). Like a shotgun being locked and loaded, this air mass is just waiting for the hammer to fall. The cold front is the hammer and as it continues moving eastward it applies more and more pressure on the trigger.
Like last week, ImpactWeather’s StormWatch team continues to warn of excessive rainfall, severe thunderstorms and tornadic activity. Additionally, strong winds, flash flooding and frequent lightning will be an issue — not only today, but tomorrow and to a lesser degree Wednesday.
In what may be a surprise move when considering typical springtime cold fronts, this one does not march across the country from coast to coast. As a testament to the strength of the high pressure system sitting over the eastern half of the country, the cold front reaches the outer edges of the high pressure and begins to crumble from the Great Lakes to the southern Plains. That said, showers across the Midwest and a disruption of the heat transfer from Texas will allow a return to seasonal, even below-seasonal temperatures to this region — what was bikini season yesterday will be sweatshirt and jacket season in a few days.
As if you needed more to stimulate your senses, there’s lots going on if you turn your attention spaceward. First, we have the spring, March or vernal equinox occurring tomorrow (0541 UTC). The equinox marks the first day of spring, so all of you enjoying the beaches of Illinois, Wisconsin and Minnesota remember that today is the last day of winter. The spring equinox occurs when the sun is directly over the Equator and halfway on it’s trip to the Tropic of Cancer and the summer solstice. Next is the new moon which occurs Thursday. Also, perhaps you can take advantage of the dark sky (thanks to the dark moon) and see the conjunction of Jupiter and Venus. This is ongoing for a couple of weeks and occurs when the two brightest planets come to within three degrees of each other. And if you can wait until the 25th and 26th, you’ll see the partial moon near the two planets — that will be quite a sight so let’s hope for clear skies.