It's been years since we've seen such a slow start to our annual 90°F day tally in Denver. To date, Denver has recorded just seven 90°F+ days since the start of the year, which is the lowest count for the period we've seen since 2009. In the years since 2015, every year has had at least 15 90°F days through July 20th until this year, with more than 30 (30!) days recording last year by this time. Frequency of those sub-10 day years through July 20th has certainly waned in recent decades. The

The rather eye-popping heat we've seen across the southern and southwestern U.S. this summer continues to grab headlines, and for good reason. It's been hot. Remarkably so in some cases. In Phoenix we've seen a record-setting heatwave on multiple levels. Through the first 19 days of July the city has run an average temperature of 102.2°F, making it the hottest July 1 - 19 period on record, crushing the previous record of 99.2°F by 3.0°F set back in 2007. Of the top 10 July 1 - July 19 averag

Obviously, it's way too early to create a specific winter forecast, but as we sit in the heat, there is value in looking at where this current Niño sits, its forecast, and how that forecast can be compared to past years. Let's have that discussion - video: For additional reading about El Niño and Colorado: A Closer look at What El Niño Means for Rain and Snow in ColoradoThere has been a great deal of interest in El Niño recently, following multiple authoritative statements that it is on track

The latest drought monitor for Colorado was completely blank, not even abnormally dry areas across the map. This is only one of four states that can brag about being drought free. Now, this obviously isn't the first time that Colorado has been drought free but it does not happen often. In the past 23 years, it has only happened one other time - during the El Niño of 2019. You'll probably ask, "How long will it last?" Consider the southwestern part of the state is drying out, this situation won

Just a short update on the current status, and where we are likely heading with El Niño. First, here is a look at the current sea surface temperature anomalies: Very  warm water just off the west coast of South America, and that warmer  than average water extends westward across the equatorial Pacific Ocean. Overall, the Pacific Ocean continues to warm, despite a few spots that  are currently cooler than average. All of the  forecast models continue to develop this episode further, during th

Wet weather continues with scattered storms giving heavy rainfall for parts of the state again today. This continues a wet trend established in May for those east of the mountains. In some cases, record precipitation fell in parts of the metro area this May, however, a record minimum amount fell over the Northwest surrounding Steamboat Springs. That is a PRISM dataset that is still preliminary for the month. Records go back to 1895. It was DIA's wettest May on record, but that record is so sho

June is upon us and is off to a wet start across parts of the plains and mountain west where scattered to numerous thunderstorms impacted day-to-day operations. As of Friday June 2nd, a number of flood alerts paint the map from Montana to Wyoming and Nebraska, and from New Mexico through Texas into Oklahoma. This is following a month of wet weather in the same zones. May 2023 was an impressive month for precipitation along the Rockies and adjacent plains. Sadly, however, deficits grew for much

The weather pattern has been active! Get a load of the rainfall anomalies for the past 30 days! Some of the rains that have been happening along and east of the mountains are some of the biggest rains we've seen in a long time. While we still have a ways to go for some areas, this is the type of pattern we've been talking about for months. Late April and May were going to be the "tell" for the developing pattern. Rainfall anomalies for the next two  weeks looks like this: Some areas of the No

It should come as no surprise that recent rainfall across the state has made a big impact on drought conditions across the state. Denver, which as recently as the April 25th Drought Monitor report was classified as being in Moderate Drought is now drought-free, thanks in large part to the record rainfall we saw across the area last week. Here is a look at the Drought Monitor from April 25th

The big topic is obviously La Niña's departure and warming conditions that will take us into El Niño rather shortly in the ocean conditions. The latest projection for El Niño in the ocean conditions is shown with rather high probabilities. The atmosphere lags behind the ocean's change - so keep that in mind. An El Niño state in the ocean's (as that probability chart depicts) does not mean the weather pattern across the U.S. will be in one for some time. Yet, even with a slow transition, we

There's a lot of snow in those Rocky Mountains, the Sierras, and the Cascades to help the water situation across the American West, and the snowpack is so much more impressive than we had expected. Let's break it down closer to the river-basin level across the Western U.S. For a video discussion, here , the written form follows. The measurements used here are based on SNOTEL (Snow Telemetry Network) [https://www.nrcs.usda.gov/wps/portal/wcc/home/aboutUs/monitoring

Astronomical Spring starts today, and it will have a "springy-vibe" across the state with rain and snow chances, including parts of the Denver area. Over the weekend we talked about the slow March weather for the city, which does continue for a couple more days at least. We’re a bit more than halfway through Denver’s snowiest month, and without much to show for itDenver’s average snowfall for March (dating back to 1882) is 11.5″ of snow. That makes it the city’s snowiest month on average, with

Good morning, La Niña is done! Now onto a neutral pattern before El Niño likely establishes itself. This may come with cheers or jeers depending on your perspective and how each affects your operations. Let's walk through some brief details about where we are and where we are headed. La Niña is gone in the sea surface conditions – the ENSO region has warmed quite a lot. Right now, the westernmost region (4) is the coolest and the easternmost region, (1.2) is warmest. Moments of La Niña contin

It's increasingly likely that La Niña is very near the end of this latest phase as the likelihood of La Niña conditions this spring falls to 14% in the latest CPC forecast released this week. Here is that forecast, shown as the probability of ENSO phase going forward through three-month seasons. For March-April-May we have an 82% probability of neutral conditions. That forecast is based on multiple model and statistical projections for sea surface temperatures (SSTs) within the ENSO 3.4 regio

The wind on the way we are used to. The colder and snowier than average November we just logged, now that's something! Preliminary monthly data for November shows Denver ended the month -3.8°F below the long-term average for the month, and with 10.9" of snow – well ahead of the 7.4" we see on average. This marks the snowiest November since 2019 (13.7"), and only the 4th time in the last 25 years the city has seen 10" of snow or more during the month. It was a cold month on the whole for the

La Niña remains in record territory as one of the strongest on record. The third-consecutive La Niña winter is headed our way, only the 3rd time this has happened since 1950. This in and of itself will have a strong influence on the winter outlook across North America.  There are factors in the Northeastern Pacific Ocean that need consideration, too, when looking at the snow forecast ahead. This video update begins with the latest La Niña data and how other ocean areas are shaping and will sh

The numbers for the 2022 water year, the period ranging from October 1, 2021 to September 30th, 2022, are in. For many folks living across the central and southern plains of the United States it was another starkly dry year, with some locations seeing their driest water year on record. > What is a water year? The term U.S.Geological Survey "water year" in reports that deal with surface-water supply is defined as the 12-month period October 1, for any given year through September 30, of the fol

La Niña continues and appears very set on being with us for a third winter in a row, which is rare as it has only happened twice before. This has implications across the American West for water issues along the Colorado River (Lake Mead will continue to make headlines) due to La Niña's propensity for drought in the Southwest.

Yes, it has been windy. And, it is safe to say it has been windier than normal around Denver and the Front Range in the past couple of months. It's important to keep things in perspective, so let's look at this from a top down approach, if you will. Wind events are common along the leeside of the Rocky Mountains, but what makes this recent pattern unusual is the scope of the winds across the U.S. as well as the frequency of strong wind events here in the city. To begin, let's take a look at A

A combination of factors lead to an urban firestorm in Boulder County Thursday's wind and subsequent firestorm that ripped through the suburbs of northwest Denver have left us all feeling some degree of helpless and awestruck in its aftermath. While the extreme wind from the downslope or Chinook wind event on December 30th was a key ingredient to a fire that quickly grew out of control, it couldn't have been possible without the backdrop of one of the region's warmest and driest six month peri

No, it's not just you. The last six months have been exceptionally warm and dry across the Front Range and Denver metro area. At Denver International Airport we've only managed 1.07" of precipitation since July first. One inch! The next driest July - December 17th period on record was in 1939, a year which saw just 1.89" over the same time. 1939 ended in the number 3 spot for driest years on record, only logging 7.58" of precipitation in the city, slightly better than the top spot of 2002 wh

Denver will officially see its latest first snow of the season on record this year, as the previous record set in 1934 came and went yesterday. Now the question becomes – by how many days will the new record be set? I wrote this little poem this morning to celebrate the moment: It'll snow eventually, Yesterday was not the day. It'll snow eventually, Today is not the day. It'll snow eventually, Tomorrow is not the day. It'll snow eventually... What do you think? The system we discus

2021 has had a fair number of 90 degree and warmer days with 34 thus far which is 11th most year to date. However, 2020 had 42 days of 90s+ by this time last year. Recently, in covering this year's 100-degree heat, we were asked about trends for 90-degree days over the years in Denver. The chart below shows count of 90-degree days between Jan 1 and Jul 31st for all years o

Today marks yet another day where an Air Quality Alert is in place along the urban corridor and much of Eastern Colorado. It's been an exceptionally smoggy summer, reminding many Denverites of the infamous brown cloud of the 1990s . While the driving forces behind this summer's poor air quality may be different than decades past, the health concerns remain. The following health warning from officials has b

Precipitation totals over the past 125 years haven't changed much for Colorado on the whole, however, county-level data reveal notable trends between months and seasons. Similar analyses have been done on a national level, and those studies also point to precipitation variability and shifts across the Lower 48. These studies have different processes and utilize different datasets, but the outcomes are rather similar amongst various methodologies. In my methodology, I take a simplistic approac