New York City saw a spring preview on Thursday. Temperatures have hit the 70s for the first time since October.

Here's why it was so warm and how long it will last.

70-degree temperatures in March aren't common, but they do happen. Usually, we see consistent readings in the 70s when we get to around Mother's Day and later.

The reason for this warm-up is because of what's known as a Bermuda High. These weather patterns often set up in the summer and can bring us heat waves. The heat is caused because of the position of the area of high pressure. It parks near Bermuda, off the East Coast. This brings a warm wind flow from the southwest. This will help to push our temperatures to around 20 degrees above the average. 

Like most spring warm-ups, the mild temperatures are short lived. That will be the case this time, too. Look for readings to return to the 50s and 60s for Friday and the weekend, and by Tuesday, we will be back in the 40s.

Often, when we get warm weather in the winter or spring, many people question if the rise in temperatures is due to climate change. Many people also have trouble enjoying the brief break from the cold because they are concerned about our changing climate. Our climate is getting warmer. Our winters are shorter. Our springs come earlier. However, a brief warm spell isn't climate change. It's weather. Climate is measured in decades, not days. 70-degree days in March are more likely due to climate change, but they aren't a direct result. Warm days do happen. The record temperature for Thursday is 76 degrees. It was set in 1946. 

Our team of meteorologists dives deep into the science of weather and breaks down timely weather data and information. To view more weather and climate stories, check out our weather blogs section.