Textbook meteorology has been at play in recent days.
I posted about this on Facebook Monday.
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After seeing it again Tuesday, I wanted to write a more in-depth piece about it.
We're talking about outflow boundaries.
Outflow boundaries and how they create new storms
You ever stand outside on a summer day? You hear the thunder in the distance, and you feel some cooler air. You know the storm is miles away, though.
That's outflow, and it's exactly as it sounds. Rain-cooled air flows outward from a thunderstorm.
At the same time, there's hot and humid air that's rising ahead of the storm. This creates a temperature boundary - almost like a miniature cold front.
Rising air along that boundary causes new storms to develop.
We'll show you what that looked like Tuesday in just a couple screenshots below.
Outflow causes rough storms Tuesday in the Triangle
This is exactly what caused storms to essentially "blow up" over parts of the Triangle Tuesday evening.
These storms brought flooding, wind damage and even fires from lightning strikes.
Before 5:00 p.m. Tuesday, you could see that little line near Hillsborough. This is the outflow that was racing out from initial storms over the Triangle.
As that outflow collided with other storms coming in from the west, BOOM!
Storms really got going over the Triangle, and they moved slowly from west to east.
This is not an uncommon occurrence in the summer time.
The collision of outflow boundaries, especially in our part of the state, can lead to more thunderstorms in the afternoon heat of the day.
We wrote about our "typical" storm zones in a previous Ask the Meteorologist.