The Week Ahead: Warm, Stormy then Cold
It’s time once again to see what’s in store for us for the week ahead. We’ll have a little bit of everything this week, including temperatures in the 50’s and 60’s, thunderstorms, temperatures in the 20’s and 30’s, and even some snow showers. Let’s dive in!
The week will likely start off with lots of sunshine. Temperatures will still be cold though, staying in the 30’s for the beginning of the week. Winds will slowly start to shift towards a more southerly direction on Wednesday, which will cause us to warm up! The jet stream will also be well to our north, and if you’ve been reading my weekly blogs, you’ll remember that correlates with warmer temperatures! Most of the region will see temperatures in the 50’s from Wednesday through Friday, and some areas may even see some temperature readings in the 60’s. The arrows in the image below is where the jet stream will be from Wednesday through Friday.
Unfortunately, this warm up will be short-lived, as we will cool back down this weekend. Temperatures will return to the 20’s and 30’s on Saturday and Sunday. That’s quite a drastic temperature difference. There has to be a driving force to cause the weather to drastically change from mild to cold. That driving force will be a cold front. A cold front will slowly approach from the west beginning Wednesday night, and ahead of it will be a chance for moderate-to-heavy rain, and even a couple rumbles of thunder. I’m not expecting any severe weather as of right now, and I’ll explain why below.
Just like a chef has ingredients for his recipes, the atmosphere needs ingredients for thunderstorms to turn severe. The three most important ingredients the atmosphere needs in order to create severe weather are instability, wind shear, and a lifting mechanism. Confused? I’ll explain. Instability is basically the same thing as atmospheric fuel. Instability can be created by lots of sunlight or plenty of moisture. Wind shear is essentially how the winds change from the surface to near the top of the troposphere. More wind shear usually, but not always, signals more severe thunderstorms. A lifting mechanism is something that funnels all of the important ingredients from the surface up to the clouds, where strong thunderstorms can form.
For this setup, we’ll have plenty of wind shear, but the instability will be lacking. Below are two model-generated images of cloud cover for Thursday (courtesy of pivotalweather.com). The top image is from the North American Mesoscale Model and the bottom image is from the American Model. The blue colors signify intensified cloud coverage. Clouds will definitely be thick on Thursday, which is why we won’t have much instability. Imagine if a chef didn’t have enough sugar for his award winning cookies recipe; the cookies would not taste as good. The same applies with the atmosphere; because instability will be lacking, the severe weather threat will be almost non existent. A few rumbles of thunder are possible with the rain on Thursday, but that’s just about it.
After all of this, it will turn very cold once again! Colder air will funnel down from Canada, and temperatures will be back to the 20’s and 30’s for the weekend. Like I always say, March is the battleground between Winter and Spring. Thankfully, Spring officially arrives next week on Wednesday, March 20th! We know that this doesn’t mean the temperatures will automatically stay warm after March 20th, but it’s certainly a pleasant thought of better things to come.