While still uncertain, there is at least a chance for significant severe weather in parts of the Finger Lakes on Tuesday, including the potential for tornadoes.
Tuesday Weather Set Up
The weather set up for Tuesday is rather uncommon for our area during the summer months. A strong area of low pressure, the combination of the storm responsible for the massive flooding in Louisiana and a second system from Canada, will track across Lake Ontario Tuesday afternoon.
Given the strength of the low, and its close proximity to the region, winds should be strong both at the surface and above the surface. Not only will winds be strong, they will also be coming from different directions. Surface winds will be from the southeast or south, while just above the surface, winds will be from the southwest or west.
Strong winds that turn with height are a necessary ingredient for severe, potentially tornadic thunderstorms.
Out ahead of this low, a warm front will lift through the region Tuesday morning. Behind this front, the oppressive humidity from the weekend will move back into the Finger Lakes.
Uncertainties & Limiting Factors
Three of the four ingredients for a severe weather outbreak look to be in place Tuesday: a strong, nearby storm system, strong winds throughout the atmosphere, and very moist air. However, the fourth and final ingredient is uncertain and will be the difference between a serious situation or a non-event.
Moisture alone is not enough to fuel thunderstorms- it needs to be hot, too. This is especially the case with Tuesday’s set up because there is a lack of cold air aloft to create an an inbalance in the atmosphere.
Therefore, the big question becomes whether the sun will come out to supply the necessary surface heating during the morning and early afternoon hours on Tuesday.
As the warm front moves through the Finger Lakes, it will be accompanied by showers and clouds. South of the front, the sun will come out and heat the atmosphere. Whether that happens over the Finger Lakes and Central New York, or remains locked away to the south is uncertain.
If the heating remains south of our area, the strong heating and strong winds will not overlap, and a big ticket severe weather event will not occur. However, if the heating comes far enough north and overlaps with the strong wind fields, the potential will exist for all modes of severe thunderstorms, including supercells with the potential for tornadoes.
What to do Monday
At this time, the severe weather potential is balancing along a very fine line. Tuesday could easily end up as a serious event, but it could also just as easily fizzle to nothing. It is important to keep that in mind and communicate that with others when you talk about this event.
Continue to monitor the forecast closely, keeping in mind that the forecast may not become clear until just hours before thunderstorms will potentially develop during the mid and late afternoon hours Tuesday. Having a plan of action in place now is a good idea, just in case.
As meteorologists, it is our job to raise awareness of potentially dangerous weather. It is also our responsibility to be clear about the uncertainties. I cannot stress enough that this is uncertain and does not mean tornadoes are certainly going to happen. It is better to prepare and be aware of the possibilities than to be caught off guard.