Much to everyone’s surprise, what was forecast to be not much more than a dusting of snow turned into quite a bit more. In Thornton from about 6:00pm to 7:00pm we saw 1.5″ fall very quickly with near blizzard conditions for that brief period. Much of the Denver metro area saw more snow than that, primarily west of I-25 and south of I-70. Not far from us Broomfield reported 3.4″ and Federal Heights 3″.
Why did this storm offer more than predicted? Here is what 7News’ meterologists offer:
Computer models had shown little if any snow across Denver. However, instability in the atmosphere provided enough juice for a convective-type snowfall. Reports of thundersnow came from southwest Denver near Chatfield State Park as a result of the instability early Wednesday afternoon.
This type of snow is called CSI, Conditional Symmetric Instability. It is generated when enough instability exists in the atmosphere to give snow showers a thunderstorm-type development. With help from upslope flow, these snow events can dump a lot of snow in a short period of time. While these events don’t last more than a few hours in most cases, snowfall rates as high as 2 to 3 inches can amount to excessive accumulation.
For the foreseeable future we expect to stay pretty dry. Our next chance for snow comes Monday and into Tuesday. No predictions yet on amounts of snow as it is too far out and the models aren’t consistent yet. Until then, temperatures should be pretty seasonable.