Weather fronts play a crucial role in our weather across the nation. From cold fronts to dry lines, we pretty much see it all here in West Texas. Before we get into the different types of fronts, we need to go back to the basics: Air masses. There are four air masses that we see here across the continental U.S. These air masses are Continental Polar (cold & dry air), Continental Tropical (warm & dry air), Maritime Polar (cold & moist air), and Maritime Tropical (warm & moist air). In between these air masses are boundaries. These boundaries are called fronts, which is the exact definition of a front: The boundary between two air masses. 

The most common type of front is the cold front. Cold fronts can bring rain and severe storms across the U.S. as well as cooler air. Cold fronts form when colder air replaces warmer air. Cold fronts bring major changes in temperatures and many other atmospheric variables. After the passage of a cold front, temperatures become cooler, winds drastically change directions, and much drier air is replaced compared to the warm, moist air we see ahead of the cold front.

The second most common type of front is a warm front. A warm front occurs when warmer air replaces cooler air. Warm fronts still happen with your typical low pressure system, but the reason why you don’t hear much about it is because they’re usually not as drastic and severe as cold fronts. Cold fronts can back some severe weather with them under the right conditions, but don’t let warm front fool you. Also under the right conditions, especially during severe weather season, they can bring some severe weather themselves. 

You’ll occasionally hear us talk about a stationary front, but you don’t hear us talk about it that often. That’s because this front isn’t really a weather maker because it doesn’t move, hence the term stationary front. Stationary fronts form when cold fronts stall. They only really happen here in the South Plains when a cold front draped across the region stops moving, keeping temperatures to the north much colder than temperatures to the south.

This next front is more of a small scale front and drives nearly all of our severe weather in West Texas: The dry line. The dry line is the boundary between moist and dry air masses. Dry lines mostly form during the spring and summer, and that clash moist and dry air helps give us that severe weather.

The final front that we hear about here on the South Plains, but is not by definition a true front. The front we’re talking about is the gust front, also known as the outflow boundary. The gust front forms when thunderstorms develop and bring rain cooled air down to the surface. The cold air hits the ground and pushes away from the storm bringing gusty winds and rain cooled air to wherever it moves. Those gusty winds and cooler air boundary is the gust front.

If you would like to read more about different types of large scale fronts you can head here: https://okfirst.mesonet.org/train/meteorology/Fronts.html