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Forecast Discussion:
Looking quickly at the 7 am snow reports on Thursday - a trace to a quarter inch of snow/ice pellets and freezing drizzle coated the land from Boulder to Longmont (Figure 0). We also had an extended period of freezing fog in the morning. Denver picked up more ice/snow than we did as a convective band set up across the mountains into Denver proper. The avalanche danger continues to increase up in the high country.
The world is officially in an El Niño state (it was in a sub-class of El Niño up until now - a Modoki El Niño - where the warm ocean anomaly was more located in the central Pacific than in the eastern side as we would expect - Figure 2).
The upper-air pattern coupled with generous amounts of subtropical moisture keep the flow of moisture pouring into the west and southwest (Figure 3 - green arrow and white/purple clouds).
By tonight (Friday pm) another low will interact with that moisture and KEEP dumping snow on the mountains. (I think I heard Vail has roared past 300 inches of snow this season). (Figure 3) Similar to Wednesday/Thursday- the big stuff will fall in the mountains with some snow/ice out on the Plains. This is being kicked off by the short wave seen just past us Saturday morning as the red dash east of us in Figure 4).
The period of time for low-land precipitation will be short again; afternoon and early evening Friday (Figure 5). Note, no real cold air gets pulled back to I-25 this time. The GFS shows a trace to a coating again along I-25 (Figure 6).
The longer range forecast:
We stay just a bit below normal for the next 10 days (Figure 4) and some models (there is a lot of disagreement) show a big cut off low forming in the SW U.S. that could drop real snow along the Front Range Monday-Wednesday next week.
Looking back at the El Niño conditions - since these ocean temperatures and global wind field patterns are expected to remain in place this year, there is a longer range outlook to May posted by NOAA (Figure 7). They are calling for good chances of above normal precipitation over Colorado and near normal temperatures. (The WeatherBell forecasters are calling for above normal precipitation and below normal temperatures for most of Colorado). Both of these forecasts mean we probably have a good amount of snow yet to come. Keep that shovel ready.
