You may have gotten a notification or noticed a post for a snow squall warning this afternoon. If you found yourself confused thinking to yourself "What is this, I've never seen this before?" Don't feel bad. It is a brand new warning service product the NWS will be issuing starting this year.
The official criteria for the NWS to issue a snow squall warning is as follows:
These types of warnings are intended for quick hitting snows that will cause travel issues. The amount of snow that will accumulate has little to do with the warning. In fact, many snow squalls will fail to produce more than an inch of snow due to their fast hitting nature.
Also, the strong, sometimes severe winds that can be produced with snow squalls will cause minor damage, similar to what is seen with straight line winds in thunderstorms. Additionally, snow squall warnings could be issued during a large scale event where say, a winter storm advisory is issued. It is important to note the details in each warning product that is issued to understand the hazards.
An un-warned snow squall near Des Moines, IA today (Monday December 9th) caused a pile-up on I-80 with at least one Injury. The snow only accumulated to an inch or less, but the quickly changing conditions made for extremely dangerous travel. It is these types of scenarios this new product is intended to make people aware of.
So, be on the lookout for these types of warnings this winter season! They will show up on most radar apps as well.