A few of you have asked about air quality websites. I do the same thing that most of you probably do, search the web. Look for official sites like Colorado.gov.
I also like to look at satellite because smoke conditions change fast. The RAMMB Slider (google it) offers a range of satellite options and you can zoom in. The afternoon and early evening is the best time to look because that’s when fires are most active. The satellite won’t necessarily tell you how bad it is at ground level, but you can see which smoke plumes are activity growing and where they are going.
10:30 AM MDT, Friday, August 14, 2020
A large upper level high centered over our region has kept it dry and hot. That upper high will strengthen but also shift westward a little so that it’s centered over Utah and Nevada. For the Front Range and eastern Colorado that means that some slightly less hot air may slip in from the northern plains every now and then over the next 5-7 days. In fact the first example of that is moving southward through eastern Colorado right now, and so today’s hot temperatures may top out early and then fall off a little this afternoon. But don’t expect any truly long-lived switch to cooler weather; we are still in a warm and dry pattern. If you are heading west for the weekend, record and near-record hot temperatures are likely over western Colorado, Utah, and the Southwest.
A slight increase in atmospheric moisture through the weekend may bring back the chance for some isolated late-day thunderstorms. But I expect most areas will not experience any rain of substance over at least the next five days. I hope I’m wrong.
Many parts of the Front Range have been experience terrible air quality due to wildfires in western Colorado. I have good news and bad news about that. The good news is that as the upper high strengthens to our west, our winds above the surface will switch from west to more northwest or north. So smoke from the western Colorado fires will not drift this way anymore. The bad news is that with high fire danger throughout Colorado and Wyoming, new fires locally or to the north could be a new source of smoke. In fact a fire west of Fort Collins this morning is expanding as I write.
Enjoy the weekend, and be very careful with fire!
12:45 PM MDT, Friday, August 7, 2020
If you are looking for a weekend with almost no chance for afternoon thunderstorms in Colorado, this may be your weekend. An anomalously dry air mass will be over the central Rockies region keeping the chance for afternoon thunderstorms at nearly zero. Lower elevation temperatures should get well into the 90s each day.
Monday will probably bring back some afternoon clouds and a small chance for rain. But in general, a warm and dry pattern will likely remain over us for at least a week.
Although some very localized parts of the Denver to Cheyenne corridor have benefitted from a good soaking at some point over the last 6 weeks, the pattern has been so dry that most areas have not. Denver’s official station at DIA has had less than 50% average rainfall in June and July and isn’t doing any better so far in August. Fort Collins had one of their driest Julys on record with a mere 0.15″ for the whole month. Boulder was about average in June, but measured only 0.34″ in July, or about 20% of average. Please use care with fire when you are out recreating!
8:20 AM MDT, Friday, July 24, 2020
One of the seasonal cycles that we look for each July is the Southwest monsoon (also called the Mexican monsoon and the North American monsoon). During this cycle intense thunderstorms form each day in the coastal mountains of Mexico and pump moisture into the atmosphere. That moisture gradually makes its way north in July and August into the southwestern U.S., sometimes as far north as Colorado, sometimes not that far. Late July and early August tends to be the peak time for monsoon moisture along the Front Range.
There has been a lot of westerly winds this month which has made for a weak or non-existent monsoon for the Front Range region. But today through early next week will likely see a couple intrusions of that monsoon moisture and more areal coverage of afternoon/evening showers and thunderstorms.
Long range forecast models suggest that by the last couple days of the month the Front Range will return to a hot and dry pattern. For now let’s hope for a some moisture for the local vegetation.
6:00 AM MDT, Monday, July 13, 2020
Today will be another hot day. There is a small chance of thunderstorms for the foothills and urban corridor, but the chance is greater across the eastern plains where a few severe thunderstorms will probably develop.
We will see a break in the heat on Tuesday. There may even be some areas of low clouds Tuesday morning along the foothills. There will also be a few showers or thunderstorms scattered around Tuesday afternoon. Don’t get too cozy with the cooler weather. Hot weather will likely return Thursday and Friday.
3:50 PM MDT, Thursday, July 9, 2020
It appears that this prolonged period of above-average temperatures is likely to hang on until next Tuesday. And a shift to cooler on Wednesday might be temporary.
Friday has the potential for being the hottest day in this stretch. Thunderstorms on the far eastern plains of Colorado this evening may send a cool outlow of air toward the Front Range tonight that lingers into morning. But it looks like drier and hotter air will push its way through the Front Range region by afternoon resulting in high temperatures in the 95-100 range for much of the urban corridor and eastern plains.
Saturday will probably be a little cooler but still at least 90 for most low-elevation areas and little or no chance for rain. Sunday and Monday have the potential to be very hot again, but with a possible spoiler. There may be some mid level moisture arriving. It won’t be enough to result in widespread rain, but it may cause some clouds. So although the potential exists for temperatures in the 95-100 range again, cloudier areas may top out in the low 90s.
1:00 PM MDT, Friday, July 3, 2020
I haven’t written in a while because the atmosphere hasn’t presented anything that departs much from typical weather for this time of year. That is still the case, but since it’s a holiday weekend and many of us will stay local, I thought I’d do an update.
Seasonal temperatures and the small chance of afternoon thunderstorms will be with us today through Monday. The best chance for thunderstorms today will be on the eastern plains, with only a very small chance along the foothills and urban corridor. Saturday and Sunday will probably bring a better chance for thunderstorms, although still small, for the Front Range region. Looking ahead, it’s possible that the second half of this coming week might get us into a real heat wave for the Front Range region.
5:15 AM MST, Wednesday, June 17, 2020
The current spell of hot, dry weather will take a temporary hiatus Thursday and Friday. Afternoon temperatures on Thursday are likely to be 15-20 degrees cooler than they have been these last few days. There will also be an increased chance for showers and thunderstorms Thursday afternoon and evening, and maybe on Friday too. Not everyone will benefit from some rain, but it will likely be the best chance we have seen for rain in a while, and there may be a few local spots with locally strong thunderstorms. We will probably trend back toward warmer weather over the weekend just in time for the June solstice on Saturday afternoon at 3:44 PM.
5:25 AM MDT, Saturday, June 6, 2020
Thunderstorms are likely to move through the Front Range region this afternoon, and a few spots may see brief heavy rain & hail. Many areas won’t get the heavy precipitation, but gusty winds are likely across a big portion of the area. The atmosphere should dry out this evening and another warm day is expected Sunday with little or no rain.
A cold front Sunday evening should usher in a cooler air mass with gusty winds. Afternoon highs will be somewhat cooler Monday and Tuesday. There may even be some areas of low clouds and drizzle that develop in and near the foothills on Monday.
5 PM MDT, Friday, May 22, 2020
The Front Range region has been drier and a little warmer than average so for this month. The best chance for widespread rain that we have seen in a while will arrive on Sunday. After a warm day Saturday, and dry for most areas, the chance for showers and thunderstorms increases by Sunday afternoon along with lower elevation temperatures no warmer than the 60s. We may even see a period of chilly rain or drizzle Sunday night. And yes, snow is likely to whiten up the mountains above treeline, and the snow level may drop down close to the elevations of Nederland and Estes Park.
Monday should be cool, but probably not too bad; 60s in the lower elevations after a damp & chilly start to the day. Warmer weather is likely to return Tuesday.