HOUSTON – Working in the world of weather can be quite a bumpy ride when it comes to making sure forecasts are accurate as the atmosphere can throw a variety of changes at meteorologists. Sometimes, though, all the ingredients line up just right and can help meteorologists like the Stormtracker 2 Weather Team to provide a highly confident forecast.
A little background:
To understand how tricky weather forecasting can be, it’s crucial to know what the atmosphere is really is. The atmosphere is fluid. Think of the atmosphere like a river that your watching as you walk along a path. While the water is usually flowing in the same direction (a la the jet stream), you can always spot little changes in the flow (called eddies) that will disrupt the overall flow in small, but sometimes, significant ways.
Those little changes can have big consequences in how we interpret our weather models that we use to put together our forecasts, especially a very important forecast like many where relying on this week as the snow was lurking.
Before the snow:
We knew that there was good consensus that most of the southern U.S. was going to be seeing a huge outbreak of Arctic air the week of the 21st-25th of January. So, we knew that one of the main ingredients for wintry weather was going to be here: very cold air.
Most of the longer-range models also were hinting that a surface-based area of low pressure was going to develop just off the southern coast of Texas and drag northward across the Gulf Coast states Tuesday into Wednesday. While it’s not uncommon that both the (commonly used) longer range models, the American (GFS) and the European (Euro), show similar solutions when big storm systems are projected, they usually will have significant differences in timing, intensity, and location.
This time however both models were telling a very similar story about one week before the storm arrived late on Monday, the 20th. When the long range forecast is consistent we have a much higher confidence.
Clearly, as you can see above, the Euro was more aggressive with the snowfall, which ultimately turned out to be the right solution! But even the GFS was saying that there would be snow moving in as the storm system moved up from the coast. Therefore, we had a very confident idea that the two main ingredients in place for snow: Very cold air already here and plenty of gulf moisture to move into that cold air.
Our weekend before forecast:
With model consistency our team felt pretty confident the week before we would see snowfall. The next question was how much snow would fall. By Thursday evening we began to forecast 2-6″ for SE Texas. On Friday morning, Chief Meteorologist Anthony Yanez confidently wrote in his newsletter “snow totals should range from 2″-6″ in Houston!”
As we went through the weekend our forecast continued to become more refined. By the time we got to Sunday we had a snow forecast that nearly perfectly aligned with what actually fell across SE Texas. Take a look at the snow forecast Meteorologist Daji Aswad showed at 5 p.m. on Sunday below.
You’ll see the dark blue where we expected the highest totals.
Actual snowfall totals were very spot on with the forecast. Below you can see the radar estimated snowfall totals across SE Texas. In dark blue you can see the highest totals across our area.
Accurate forecasts are critical for planning during major weather events. We were thrilled to see the city plan closures in advance of the winter storm. This helped keep Texans safe and off the roads when the heavy snowfall was falling.
