A Note on Lead Time

Some have asked (prematurely) what has led to a relatively quiet (so far) hurricane season in Atlantic Canada. While it is true that the number of storms (to date) that have impacted the area is lower, there are some trends that we should be very aware of.

Severe Storms or Hurricanes (up to End Nov)

First, Beryl showed us just how quickly a relatively minor storm could turn into a significant hurricane. This only took a few days. Also noteworthy was how quickly Helene went from being a depression to one of the deadliest storms on record in the USA. These factors emphasize the need to be watchful and not to discount evolving situations because they look “manageable” at the time.

All told, hurricanes forming in the Eastern Atlantic and following paths that swing northward to Canada generally offer around 4-6 days worth of warning for those that are checking these kinds of things.

Second, we need to be cautious of storms that have formed along the southeast coast of the USA that come up along the coast. These have shown signs that they could evolve into cyclonic storms. These tend to run up along the coast (if they don’t push eastward).

These storms may evolve and move quickly, offering only 2-4 days warning that they are coming.

Finally, we also see storms that can turn into significant storms that develop or evolve into more significant storms off the northeastern USA. These storms may form into more significant storms, but tend to really evolve once they get past the cooler waters that surround Nova Scotia and hit the warmer waters that come up from the south.

These storms may form rapidly, offering only 1-2 days warning that they are coming.

Winter

As we move towards the winter, we are currently looking at heavier snowfalls predominantly in the Atlantic Canada region. Given how weather systems behaved last winter and this summer, we should also be prepared for weather that has systems colliding into rather heavy storms. These may offer only a couple of days worth of lead time.