As the fall season slowly transitions to winter, a common problem that professionals deal with is drizzle. With light, measurable totals, and a tendency to see a drop in visibilities, it’s more of an annoyance than a hazardous weather type for the general public. However, it can be one of the more pesky types of precipitation and create headaches for decision makers. When safety concerns arise for schools, concrete or asphalt jobs or other outdoor professional projects that have zero tolerance for moisture, it can be frustrating and costly when a weather app doesn’t show any chances. On some occasions, even conventional radar will struggle to “see” mist and drizzle.
From a meteorological standpoint, drizzle often occurs when low clouds push over an area with increasing low level moisture. For locations near a large body of water, such as the Great Lakes, a strong northwesterly wind can aid in drizzle developing with little notice. It is very common as moisture remains higher coming off of the warm season, but colder air begins filtering in as winter approaches.
So if it is relatively common, why does it not show up on radar or weather apps?
While advancements have been made in weather modeling over the past few decades, there are still certain weather scenarios that current technology is not equipped to handle with accuracy. Drizzle is one of those scenarios. Weather models will struggle to pick up on drizzle because in most cases, the droplets will be so small that they won’t result in any measurable rainfall. When measurable rainfall fails to register on most models, regardless of what source you are looking at, rain chances won’t show up.
A similar problem exists for radars, especially on free apps that are not using high resolution reflectivity tools. Water droplets can be so small, that the radar beams will not always “reflect” off of the liquid, leading to no reflectivity signals on the radar and nothing visible showing to the untrained eye. However, trained meteorologists can examine additional tools such as atmospheric soundings to forecast drizzle.
To mitigate these situations, BAM Weather has develop a tool called “Forecast Correction Insights”. These insights provide custom commentary from a trained team of meteorologists and specifically highlight situations where data will miss pesky drizzle that can wreak havoc of outdoor decision making. While we no one can fully control hourly automated data, BAM Weather’s custom forecast insights and corrections can “fill in the blank” and prevent lost time, money and stress for even the most minor weather events.