In Part 3 of our week long series, I wanted to focus on the final “forecast” product issued on a national scale before a severe weather event strikes. It’s called the mesoscale discussion. In a way it’s almost like a precursor to a severe weather watch, IF one is issued. The graphic to the right shows one mesoscale discussion issued for the Gulf Coast earlier this year. You can see the red squiggly line highlighting an area at risk for severe weather.
Along with these highlighted areas is a technical discussions talking about what the Storm Prediction Center expects to happen over the next 1-3 hours. These mesoscale discussions serve as the final preliminary forecast before a severe weather watch is issued. They allow storm chasers and forecasters a chance to know what the SPC is thinking when it comes to issuing watches.
This product serves as the go between from the general severe weather forecasts to the issuing of a severe weather watch. It is an effort to provide extra warning before storms develop over a specific area.
Besides severe weather, the mesoscale discussion is also used in times of extreme winter weather as well. Often, the SPC will use them to discuss heavy snow events, blizzards and freezing rain. The primary benefit of these discussions is to better inform and prepare trained professionals of the weather that might impact them. Generally mesoscale discussions have little place in reports given over television and radio. But they are accessible by the general public at any time by going to the Storm Prediction Center website.
Now I know today’s post is a little shorter than usual but I know that tomorrow’s segment will make up for that. Part 4 of our special series will cover watches and warnings. Although many find them easy to decipher, there is a lot of information behind the issuance of a watch. We’ll get into that and what exactly a PDS watch is in our next report.