When it comes to warm fronts there’s a real love/hate relationship storm chasers possess with them.
On one hand, some incredible cyclic tornado machines have occurred on warm fronts — on the other they can be quite fickle when it comes to getting the right ingredients to come together.
Let’s learn about them!
Why warm fronts work…
At their most favorable, warm fronts will create an incredible west-east region of enhanced vorticity and low LCLs. This is an idealized tornado environment with tons of potential. But, not all warm fronts are made equal.
You will want to target these when it looks likely storms will form and stay relatively isolated. It is also important to make note of storm motion. Motions that parallel the boundary are much more favorable than motions more perpendicular. This is especially true when storm motion roughly lines up parallel to a warm front’s orientation. In these scenarios, a storm has a relatively higher chance of being a big time severe weather producer.
If capping is strong or a warm front is moving north, you definitely want to avoid targeting these as storms may have a difficult time forming. This is doubly true if overall forcing in the mid and upper levels is weak.
Another time to avoid warm fronts is when the mean storm motion is going to result in storms quickly crossing over the boundary. For a storm to take advantage of the most favorable parts of warm fronts, they need to ride along the boundary and not simply quickly cross over them.