Good afternoon on a rather reasonable TGIF in the KC area. Skies are partly cloudy but at least the temperatures are seasonable for early December. Right now it’s in the upper 40s in the area at it appears that temperatures will be cool over the weekend. It’s next week that the bigger changes take place…we’ll step back on Tuesday then drop on Wednesday. So it goes as this December (at least for the next 10+ days) will be vastly different than last December in these parts.
By the way, if you’re in the Olathe area and have a quiet early evening…stop by the Olathe Tree Lighting ceremony as we light up the Olathe Community Center starting at around 6PM tonight. I look forward to seeing some of you out there…plus Santa will make an early appearance too.
Tonight: Partly cloudy and chilly but not too terrible. Lows in the upper 20s
Saturday: Increasing clouds (lowering and thickening) with some sprinkles possible later in the afternoon. Light rain is likely at night. There may be a few ice pellets or snowflakes mixed in the farther north you go. Highs 40-45°
Sunday: Rain ends rather quickly in the AM with some clearing in the PM. Highs well into the 40s.
Well we’re starting December OK in the area…but the water vapor loop shows some changes about to move into the region. If you look outside this afternoon you’ll notice some cirrus clouds moving this way…a sign of moisture. The water vapor loop shows a twist (disturbance) across the SW part of the country as I type this blog.
Moisture ahead of that wave is moving through the southern Plains states towards our area. Also notice the faster motion to the moisture in the western US. Another little wave is out there and moving towards the Rockies.
The twist that you see in AZ will be dropping into Mexico over the weekend…then eventually kicking out through TX on Monday. The extra disturbance in the western US will move through the Rockies this weekend. The two though will allow more of a SW flow aloft to develop tonight into Sunday. That SW flow aloft will allow small little ripples to zip from the SW to the NE over the next 36 hours. This is slowly start saturating the atmosphere tomorrow morning. You will be able to notice this happening because the clouds will get grayer and lower in the sky as move through Saturday (a sign of a moistening atmosphere).
Eventually the atmosphere will support rain…and that will be the issue later tomorrow into tomorrow night and Sunday morning. This moisture will then be stripped away from KC after daybreak Sunday and the weather will start to improve again for the tail end of the weekend.
You can see how this plays out using the NAM model…as we go up to about 18,000 feet or the 500mb pressure level.
Notice the SW circulation dropping into Mexico…then coming out and eventually passing south of the KC area. As that occurs there is a little “U” that moves through the Rockies. So one saturates the atmosphere and the other helps to lift that saturated air and create rain locally.
Not too far away though, where the atmosphere will be a bit colder (towards the IA border) it wouldn’t shock me to hear about a bit of snow. It will be tough to get accumulating snow because temperatures will be above freezing through the weekend it appears…but it’s something northern MO should at least somewhat pay attention too. The NAM model shows the development of the precip.
These models will auto-update over the weekend so you always have the latest information.
I’m not jumping up and down regarding a lot of rain from this…but hopefully .1-.5″ is doable for some areas.
Meanwhile the next concern is the cold weather. Data today suggests that there may be a step down approach to the cold. An initial push comes Tuesday…then the plunge comes on Wednesday. This WILL BE a real deal shot of cold air…with Arctic origins…so it’s going to be nasty cold and nasty windy here from Wednesday into Friday morning it appears.
Take a look at the EURO model forecasts…and notice the change from Monday (50+°_ to Thursday/Friday (struggling for 20-25°).
I’m not particularly fond of how the GFS model is dealing with this. That model brings the arctic air in too quickly on Tuesday and then gets rid of it too quickly Friday. The EURO usually does best with these cold air plunges in my opinion. It also shows the potential cold temperatures better.
As I’ve mentioned lately…that game on Thursday night at Arrowhead is NASTY cold with wind chills near 0°.
Let’s go up to about 5000′ and show the anomalies. This puts the incoming air mass into perspective when looking at the typical early December air mass for the Plains.
Those light greens and blueish colors for THU>FRI show temperatures above us some 25+° F below average. That is a cold air mass! I’m not sure we had an air mass like that come down all last winter that sustained itself. I did find that in mid January of 2016…we did see our temperatures get to about these cold readings that are progged to move into the area later next week. Our highs were near 20° and the lows were sub-zero. I’m beginning to think that next FRI AM has the potential to dip to 0-+5°. Again I’m using history to forecast the future. We did have about 1-2″ of snow on the ground when this occurred…again something to pay attention too. We’ll see if others react down the road to my thoughts.
As far as the snow situation goes…I still feel it’s on the table and really my thought process hasn’t changed at this point. IF we’re going to get an accumulating snow here…it will be on Wednesday. Odds aren’t in our favor for a big accumulation (6″+) at this point…but a nuisance snow is possible and may effect the evening rush on Wednesday. Some model data shows us getting nothing from this change…I still think the chance is there for at least some accumulation and it will be a wind blowing event too.
More on those prospects later in the weekend.
Also this weekend on Sunday…the 4th annual Lighting Of The “Joe” will take place. This will occur during the 8AM hour on Sunday morning. Yes…gather the kids and wake the neighbors as once again I’ll make a fool out of myself for your entertainment.
OK that’s enough for today. Next blog will be Saturday by 2PM or so. Have a great weekend!
Our feature photo today is from Anthony Spinler.