We mark Flood Awareness Week with the National Weather Service to highlight one of the deadliest potential natural disasters.
YORK, Pa. — Note: The video is from 2020.
While it might not be the quickest or most “exciting” natural phenomenon in the weather community, more damage is caused by flooding than any other type of natural disaster on average.
Now, part of that is because flooding isn’t just about it raining a lot over a short period of time. You have river flooding, storm surge and coastal flooding, areal flooding on top of flash flooding. That’s a lot of flooding.
Once we get into hurricane season, we’ll talk more about storm surge, coastal flooding and the like.
But for today, let’s focus here at home.
The two most common causes of flooding for us in Pennsylvania are excessive rainfall from storms or tropical systems and snow melt.
Excessive rainfall might sound pretty easy to understand: too much rainfall overwhelms our area and the rain adds up. But excessive rainfall in our area leads, more often than not, to river flooding — as opposed to flash flooding.
And it’s usually hardest on our creeks and streams more than the mighty Susquehanna River.
RELATED: Severe Weather Awareness Week: Causes and dangers of river flooding
Tributaries of the main river channel are often overwhelmed because their banks are shorter and their beds shallower because they’re often only a couple feet deep. Areas that are great for kayaking or fly fishing that can easily get overwhelmed.
For us, a few creeks and streams come to mind each and every time: the Swatara Creek, the Conodoguinet, and the Yellow Breeches, just to name a few.
They’re all beautiful, family friendly creeks and streams that easily get out of hand and flood given the proper conditions.
Back in 2018, a tributary of the Susquehanna River near Accomac Road in York County received several inches of rainfall in just a couple of hours. That led to Kreutz Creek Road near Hallam turning into a raging river. I’ve never seen anything like it.
Parts of Accomac Road still have yet to recover after being carved out by the flooding.
This type of flooding can also often occur with weakening tropical cyclones passing over our area. Lee and Agnes might come to mind immediately for long term residents of Central PA.
Snow melt can cause a heck of a lot of problems in our area as well, and this one can certainly have an impact on the Susquehanna River. Remember the Walnut Street Bridge collapse of 1996? That was caused by snow melt (with help from the ice jam).
Rapidly warming temperatures or a large rain after a big snowfall can easily cause a lot of snow to melt very quickly and cause problems.
RELATED: ‘Old Shakey’ broke off into the Susquehanna River 24 years ago today
That’s why it’s important, no matter what time of the year, to remember to have your flood plan in place. Understand the advisories, watches and warnings and what they mean. Know what the flood stages mean for creeks, streams and rivers.
And above all, heed weather warnings when they impact your area.
You can get severe weather alerts right to your phone using the FOX43 app.
–Chief Meteorologist Bradon Long
Credit: Source link
