A cold blustery day is ahead for KC…and a pretty gray one too. Clouds are rotating down through the Midwest this morning and will be with us into the evening it appears. There may be a random flurry or two out there as well…and with the winds cranking at 25-35+ MPH…it won’t be pleasant this afternoon.
The good news is that 70s are possible to likely on Tuesday. There will be a lot of wind though. Monday looks to be fabulous in the afternoon as well.
Overall a pretty dry pattern for awhile with just some scattered showers possible later tomorrow night and again on Wednesday.
Meanwhile what the heck happened yesterday afternoon?
Today: Cloudy and cold. Blustery with highs in the upper 30s
Tonight: Clearing out and chilly. A hard freeze is possible as lows drop into the mid 20s
Tomorrow/Sunday: Partly sunny and cool. Highs well into the 40s tomorrow and in the 50s on Sunday. There may be a few showers/sprinkles around early Sunday morning.
I was going to write about some early winter thoughts…I’m actually somewhat excited about the snow prospects (for you snow lovers out there). At the same time I’m tempering my expectations a bit. Then yesterday afternoon went off the rails for about 90 minutes. So let’s dive into that and we’ll get into some early winter thoughts next week at some point.
By the way our Winter Forecast Special I think is set for Saturday afternoon the 4th of December (at least that’s the current plan). We’ll likely revisit the forecasts from the team on that following Monday after the special.
So about yesterday…
I was walking around 12:00 and I noticed one small measly cumulus cloud developing north of where I was. Didn’t think much about it really but thought it was just a bit odd that it was happening when I was expecting deep blue skies after the system on Wednesday night moved through. Don’t get me wrong…99.999999% of the skies were deep and blue…except for this one cloud. I don’t think much more about it.
Then around 2PM I was starting to head towards work and that one random cloud had multiplied and now there were many clouds…and they were producing virga. Precipitation that was evaporating before it was reaching the ground…and it was very striking. Sort of like this picture from Ray Bortle out towards Centerview, MO
Rain sort of suspended in the air…and mostly evaporating as it was falling into the dry air close to the ground.
So things were happening in the atmosphere.
It was around 55°, perhaps a notch or two higher in a few spots.
Then as I was coming to work I noticed a whitish tinge to what was falling. Note in the picture above the dark tinge…that’s rain…but a whitish tinge usually indicates something frozen was falling.
An examination of the atmosphere at the time indicated that the air was near to sub-freezing about 4-5000 feet up. Here at the ground again it was well into the 50s. This set up a significant temperature change from the ground to about 5,000 feet up. When that happens, whether it be close to the ground or farther up in the atmosphere, it allows bubbles of warm air to rise.
That’s why the clouds were impressively vertical. Sort of like thunderstorms. Now add in some sort of other lift to the atmosphere that was rotating around the bottom of an upper level storm in the upper Midwest…now there are more factors generating “lift” in the atmosphere and as the clouds showed that they were ready to be lifted.
That lead to bouts of rain and snow showers. It seemed that the snow was the way things started for some and then there was a transition to rain. There were some locally heavy brief downpours as well. Again though how can this happen at 55°?
As the snow was falling through the clouds to the ground it was evaporating. We call that virga. As the evaporating snow was falling though…in those smallish vertical columns the air was cooling down. This happens when precipitation is falling into dry air. Sort of similar to getting out of a pool on a hot summer day in the desert. You feel a chill…that is the water evaporating and cooling you off.
So there were pockets of air that were cooling down while the surrounding air was in the 50s. These pockets of cooler air were then allowing the flakes that were falling to get even closer to the ground before melting totally. In some cases that flakes didn’t have time to melt much at all…and voila…snow on the ground.
I noticed that when driving through the remnants of one of these downpours…my car thermometer went from 57° to about 45°. Again we reduced the size of the warmest layer near the ground from 5000 feet to something in the neighborhood of a few thousand feet.
Marty McGarrigle sent in this video out towards the Legends…
Mathew Smith caught this out towards the Knob Noster, MO
Sean caught this out towards Lees Summit,MO
Corbin got this near Overland Park
So convectively enhanced rain and snow showers, BUT we’re not done yet. There was another type of precip falling…graupel. What the heck is that?
Graupel can form during this time of the year when we get these types of convective clouds build (which in itself is sort of unusual, at least to the degree we saw yesterday). Graupel is basically falling snowflakes that encounter super cooled water droplets as they’re falling. These water droplets attach to the delicate snowflakes and then other snowflakes attach on as well…
It differs from hail and sleet.
Although I wouldn’t have been shocked if maybe there were a couple of tiny hail stones too in other cells.
Just a crazy afternoon where things went off the tracks and it wasn’t expected at all.
Our feature photo comes from Matthew Smith, One of the other by products with these types of clouds are rainbows. There were more than a couple. He caught one and it was a double!