Damn, Denver. You’re really putting on a show right now. We just experienced out hottest August ever (which was tied with 2011) but nonetheless – it was record heat.

Now, not even a week later, there is snow in the forecast. This Labor Day Weekend is going to be hot and dry. Like, low to mid-90s for afternoon highs and lots of sunshine so enjoy your weekend plans!

Then, on our first day back to work from the long holiday weekend, we could be battling some snow on our way to work.

SNOW?! In September?!

It’s not not-normal to get snow in September in Denver. In fact, this is the first month that we typically start to see accumulating snow for the water season. September typically brings 1″ of snow to the Denver reporting station. That means that there are plenty of years where we see no snow but there are also plenty of years where we see a good amount of snow. Keep that in mind as you start seeing headlines clutter your feed.

So, Give Me The Deets

Alright, so, after we enjoy the heat of this weekend, we are going to was a blast of cold air roll down the spine of the Rockies. Models are agreeing that there will be, at a minimum, a lot of cold air around for Tuesday. Where they diverge is how much cold air and how much precipitation.

We will have a cool front move through Sunday night which will drop our high temperatures from the mid-90s on Sunday to near 90 on Monday. Then the mother ship cold front moves in on Monday.

This will plummet our temperatures from near 90 to the mid-40s for overnight lows when we wake up on Tuesday. Tuesday afternoon it’s looking, at best, that we see high temperatures in the mid 50s. A stark difference from Monday. But that it likely to change and the high temp. has been trending down…so we will see if that continues. Overnight lows into Wednesday will likely be in the 30s. Brrr!

Now, the precip portion of this forecast is going to be tricky. There will DEFINITELY be rain with this system. Monday night to Tuesday and lasting through Wednesday morning. It will be cloudy and cool and damp.

The tricky park, for us here in Denver will be “how much cold air is going to accompany the moisture?”

First Guess: Forecast Rain AND Snow

It’s definitely easier to say that there will be some decent rain that comes from this storm cycle. So, In Denver, it’s likely we get a half of an inch of rain or more. Yay! That will help a bit with the drought we have. We could get a little bit more though which would be even better. Areas near the Foothills could get more than an inch of rain which would also be amazing for them. Overall, it’s looking like a half an inch to over an inch of liquid precipitation will add up. Amazing.

Now, to the hard forecast. Snow. The NWS is thinking snow levels could drop to 8,000′ but they are anticipating that dropping since signals are pointing to more cold air. That obviously means that Denver, sitting at 5,280′, wouldn’t get in on the action and only have a cold rain. BUT with mixing and evaporational cooling and what not we could see that drop and watch a few flakes make it into the Metro areas.

If you live above 6,500-7,000′, be ready for some snow to fall. It likely won’t accumulate since we’ll be coming off a 80-90 degree stretch of weather but if we get some heavy bouts of snow, it could stick to trees and grassy or elevated surfaces.

Here are some model comparisons:

The Euro Model Snow Forecast

The EURO is the most bullish and likely the forecast that you’ll see as you scroll since it look impressive. At one point it painted 15″ of snow over Denver. Woof. While it has backed off since then, it hasn’t backed off completely and is still calling for several inches of snow to fall. Notice that there is more in the Foothills and the Palmer Divide. Remember: YOU HAVE TO ACCOUNT FOR MELTING. If 6-inches falls, none of that will probably accumulate unless it falls super quick, but it will probably still melt. This is also a bullish run for Southern Colorado.

The GFS Model

The GFS was slow to hop on the snow train but it is now showing some snow for the Denver metro. Again, more in the Foothills and more on the Palmer Divide. Account for melting, were likely to only see flakes flying rather than sticking and accumulating. Impressive nonetheless that both of these well-respected models are outputting snow for us.

The GEM/Canadian Snow Forecast

The GEM model isn’t used as much but I’m throwing it in there to show that it too, as the possibility of snow falling for Denver. Albeit, much less than the others.

Moral of the Story

It’s going to get cold and it *might* snow in Denver. It becomes a little more likely the higher up in elevation you go so consider that when you read this.

Again, regardless of snow, it will get cold.

NBM Temperatures

We will be going from near 100-degree heat this weekend to 40s for highs and snow falling in some areas. That is weather whiplash if you ask me. You will probably need to think about those sensitive plants you’ve been tending to.

We could see record highs tied or broken this weekend, then we could see record lows broken next week. Phew.

Enjoy the ride that we are about to go on!

Rain or Shine
I’m Andy Stein

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