May has been a roller coaster of a month as we’ve seen both record cold AND warmth. Check out the graphic below showing just how drastic our temperatures have been this month.
Usually once we get to the month of May, the chances of getting severe weather increase all the way into summer. Severe weather is not the most common around Rochester with most severe events developing south of the thruway, but when they do occur they usually happen during late spring and into the summer.
The first severe weather event of the season was on March 20th, 2020. This was a mere one day after the first day of astronomical spring for the northern hemisphere, and it’s been fairly quiet around Rochester ever since.
A few record breaking cold AND warm events later, it is the end of May and our next chances at seeing severe weather here in Rochester are in the forecast.
It’s been a little while since we’ve actually seen severe weather here in Rochester, so here’s a little refresher. What makes a storm severe? Here are the 3 criteria defined by the National Weather Service:
- Damaging winds up to 58 mph (50 knots) or greater
- Hail greater than 1 inch in diameter
- A tornado
As mentioned in the photo above, you can have as much lightning as the eye can see, and the storm will not be considered severe. A small percentage of severe thunderstorms can actually contain little or no lightning at all. That is why it’s so important to follow the phrase, when thunder roars go indoors. Even though the thunderstorm isn’t considered severe, it can still produce deadly lightning.
Let’s break down the difference between a severe thunderstorm WATCH versus a WARNING:
SEVERE THUNDERSTORM WATCH – a watch means the conditions are favorable for a severe thunderstorm to occur. A watch typically is issued several hours before any storm initiation is expected, sort of like a heads up and over a larger area. It’s best to keep an eye to the sky and BE ALERT for any changing weather conditions.
SEVERE THUNDERSTORM WARNING – a warning means a severe thunderstorm is CURRENTLY HAPPENING. It’s best to immediately take cover indoors and keep up to date with any developments on the strength, timing, and location of the storm.
Remember to secure any loose outdoor items as they could become flying debris in high wind events, and take shelter in a sturdy building that can protect you from the elements.
~Meteorologist Christine Gregory