Chilly air will hit Colorado on Saturday evening with possible light snow accumulations above 12,000-13,000ft for the mountains along and north of I-70. Another cold storm is likely on Tuesday evening and Wednesday with more flakes for the highest peaks.
During the summer, many computer models have predicted a cool and moist autumn season for Colorado. If the next two storms are any indication, these models may be exactly right.
On Saturday morning, the first storm will be over Idaho and will move quickly toward the east. The air will be cold enough for Montana and Wyoming to see a bit of high-elevation snow, and Colorado might also see flakes.
Forecast temperatures at 18,000ft on Saturday morning. Source: Twisterdata.com
As the cool air approaches, a line of showers will form and should push across Colorado on Saturday evening. The southern part of this line will likely dissipate as it moves over the San Juans since it will lack energy and moisture. However, the line should hold together over central and northern Colorado, especially along and north of I-70. Expect gusty winds on Saturday afternoon, culminating with showers between about 6pm-10pm on Saturday night. Temperatures could be cool enough for flakes of snow above 13,000ft, perhaps even down to 12,000ft if the showers are heavy enough and drag cold air down to the ground.
Forecast radar from the high resolution NAM model for Saturday night at 6pm. The heaviest showers will fall over northern Colorado. Source: Weatherbell.com
The coolest temperatures will occur after the showers, so we won't see a lot of snow on the highest peaks. By Sunday morning, temperatures should hover around freezing at 12,000ft.
Forecast temperatures will likely hit the freezing make at 12,000ft on Sunday morning. Source: CAIC
Sunday should be a calmer day, as should Monday.
Then another cool storm will head toward Colorado on Tuesday with the likelihood of more high-elevation snow falling on Tuesday night into Wednesday. Woohoo!
We've had very few wildfires this summer in Colorado, thanks to the cool temperatures and consistent rain. However, wildfire season extends into the fall when conditions dry out and the winds increase. Hopefully the seasonal computer forecast models will be correct and fall will be wet and cool, negating the autumn fire season and starting the winter off with a bang.
Have a great weekend and enjoy the push of cool air on Saturday night! I'll be back next week with more regular updates ... it's that time of year!
Pikes Peak at 14,110ft this morning, August 8th:
Nice to see snow once again:-)
Have a great weekend!
We've seen average to above average precipitation across most of Colorado during the month of July, including the heavy rain on the front range during the last week. This weekend should be drier, except for southern Colorado where afternoon showers will persist. Next week, temperatures will continue to be average or below average.
Earlier this week I talked about the potential for heavy rain east of the divide and north of I-70. The forecast generally panned out, with 2-3 inches of rain falling for many locations, and up to 4-6 inches in a few towns that saw heavy showers on Tuesday afternoon. The radar estimated rainfall shows the area of heaviest precipitation.
This most recent precipitation helped to ensure that totals for July were above average for most of Colorado, including the mountains. It was great to see the monsoon-induced rainfall during July, because many areas were drier than average during the month of June.
Looking at temperatures over the last two months, there is nothing remarkable to report. Though after the past two very warm summers I suppose what's remarkable about this summer is that it has been close to average. The mountains recorded hotter-than-average readings during parts of July, but overall the state has been right around normal.
To the forecast...
The next few days look great! Most areas will see minimal rainfall this weekend (except for the San Juans), so enjoy your time playing outside! As for temperatures, they should stay around average or cooler than average through the first week of August.
Many areas of eastern Colorado recorded 1-2 inches of rain over the last 24 hours, and another 1-2 inches could fall on Wednesday before the storm moves away in the evening (this is well above average for July).
The rain started on Tuesday afternoon and covered the state somewhat randomly, but by Tuesday night the atmosphere seemed to play along with the forecasts and produce a steady rain over and east of the foothills between I-70 and Wyoming.
Total accumulations from Tuesday and Tuesday night exceeded 6 inches in a few spots that saw heavy downpours on Tuesday afternoon, while the average was about 1-2 inches. This amount of rain isn't generally enough to cause widespread flooding, but it is very beneficial and should put us above average for the month.
The rain is continuing to fall now on Wednesday midday, and it should continue through the afternoon for northeastern Colorado. The mountains west of the divide are mostly dry right now, but some showers should pop up during the day.
The coldest temperature I can find during this storm is 36 degrees at 12,500ft on Berthoud Pass. It's possible that some peaks over 13,000ft might be coated in snow, and we'll have to wait until the clouds clear late Wednesday night or Thursday morning before confirming this. The best chance to see snow is along and north of I-70 from Berthoud Pass north to the Indian Peaks and Rocky Mountain National Park.
Another note about the cold. Right now (11am Wednesday) the temperature at Denver International Airport is 60F. The coldest high temperature for this date is 64 set in 2009, so we might break it if the rain and clouds are able to stick around all day and limit additional heating.
A few people wrote to me yesterday asking if the cool / wet pattern we're seeing right now will stick around for the fall and into the winter. The long-term climate models do show this. Don't get excited just yet and think that our winter will offer above-average snow, though it does seem like winter might get off to an early start. I'll post more about the winter outlook by late August and will continue to post on a daily basis if and when there is interesting weather in Colorado (like right now:-).
Thanks for reading during the summer!
Heavy rain will likely fall from Tuesday evening through Wednesday from Denver north to Wyoming and there is a high chance of flooding. Other areas of Colorado will see healthy rain but lower chances of flooding. Below-average temperatures will stay with us through early August.
Colorado has experienced a rather typical summer so far with about average precipitation and average temperatures. Of course some areas have been hotter / cooler / wetter / drier than others, but overall it's been a normal summer.
One part of a normal summer is an increase in moisture during July due to a change in wind patterns that pushes this moisture from the south into our state. This is called the "Monsoon".
We've seen a few good pushes of moisture and rainfall over the past weeks, but we're about to get the strongest push yet. When this next wave of moisture moves into northeast Colorado Tuesday and Wednesday, it will coincide with an area of energy that will help to lift the air, and lots of rain will likely result.
First, here's the moisture pushing into Colorado from the south.
Next, add an area of energy that will spin its wave over Colorado and help to lift the moist air and convert it to rain. You can see the area of spin on Tuesday morning centered over central Utah, moving toward the northeast.
The result will be rain steady rain mainy areas of the state, with the potential for flooding rains over northeast Colorado, north of I-70 and along and east of the highest mountains of the divide.
Yes, this is is the same location that the flooding occured during September 2013. The models are forecasting 2-5 inches of rain for this area during the next 36 hours. The average amount of rainfall during July for northeast Colorado is about 2 inches, so we might get 100%, 200%, or even 300% of our monthly rainfull in just a day and a half. This is why we have concerns about flooding.
Looking ahead to early August, a cool northwest flow will keep temperatures at or below average for most of Colorado during the next 10 days. If this were winter, there would be multiple powder days over the coming week. But the best I can say about this pattern during the summer is that we won't see swealtering temperatures anytime soon and there will be chances of rain most days. Fantastico!
I'll keep an eye on the flooding potential Tuesday night through Wednesday for northeastern Colorado and update as necessary. I don't want to see flooding, but I do like to see moisture in Colorado, so this might just be a case of too much of a good thing.