Colorado weather: Will Denver have a warm, dry spring ahead?

If the Climate Prediction Center’s outlook is right, Colorado could be in for a warmer and drier spring than normal.

The CPC’s 90-day outlook, which covers the months of April, May and June, puts all of Colorado as having good chances at a warmer-than-average spring and early summer, and most of the state leans drier in the outlook, as well. However, there is an unusually high degree of uncertainty with this particular long-range forecast outlook.

“Over the western (U.S.), the forecast is highly uncertain,” the CPC wrote in its forecast discussion for the three-month outlook.

The primary reason why the next few months could be especially uncertain: there isn’t expected to be a strong influence from either an El Nino or a La Nina, known as the ENSO cycle.

The ENSO cycle is in reference to abnormally warm or cool (or neutral) sea-surface temperatures in the central Pacific Ocean, and it has a big domino effect on global weather, including Colorado’s. While El Nino and La Nina influences on local weather are typically greater in the winter months, there can be some impacts on spring and summer weather as well. But, the lack of a clear-cut La Nina or El Nino (and the unlikely chances of one forming, either) make it difficult to get a great sense for the upcoming spring and early summer season.

“There’s not really any strong signals, so it’s hard to hang your hat in any direction,” said Scott Entrekin, a meteorologist at the National Weather Service office in Boulder.

The last time that conditions were ENSO neutral was in 2012 and 2013 when extreme weather was noted in the state during both summers. In 2012, the Waldo Canyon and High Park fires devastated the state, and the Black Forest fire of 2013 did the same. Additionally, in September of 2013, Colorado experienced some of its worst flooding on record.

However, it is difficult to extrapolate one single large-scale event, such as a series of large wildfires or a one-time — albeit catastrophic — flood, and attribute it to ENSO neutral conditions. It is more likely that a wide array of other meteorological factors played a far bigger role in the extreme weather during those two years.

Additionally, Colorado’s snowpack remains in healthy shape, a solid indicator that this will not be a huge wildfire season. In lower elevations, precipitation values are generally running at or above average so far this year. While pockets of southern Colorado remain in a moderate to even severe drought, less than half the state was experiencing official drought conditions, as of an April 2 update. In April 2012 and April 2013, a much wider swath of Colorado was under drought conditions than currently noted.

Of course, there may be some extra reasons to cheer for a warmer and drier spring and summer along the Front Range this year. There may be indications that a warmer and drier summer season could reduce the spread of the COVID-19 outbreak, although those findings are largely speculative.


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