Over the past few days we have been getting a lot of questions about the forecast for Tuesday, mainly because The Weather Channel released a graphic like the one to the left, showing the southeast corner of the state receiving over a foot and a half of snow. If you have seen this image, and have been sharing the word that this is a legitimate forecast, delete it right now and help us stop this inaccurate message. We would like to debunk this myth and show you the actual science and facts behind Tuesday’s forecast.
First of all, a 500mb trough will move into the northwestern United States by the end of this weekend and will then move into the central U.S. by Tuesday. This trough will split into a northern and southern component. Our weather will be caused by this southern component of the trough. Right now, since this system is still 3 days away, timing and location will be key and at this current time, it is anyone’s guess to where and when that will be.
At this current time this is what looks to happen by a few of our models. A piece of energy will move through the trough and will start to affect the state by Monday night and into early Tuesday morning. As the surface low associated with this system continues to move closer to the state, an area of widespread snowfall will then overcome the state. This widespread snowfall will occur sometime during the day on Tuesday. One issue that we do have is there will be low level dry air ahead of the system and this will cut down on the accumulations, especially across the north. The good from this system is that all precipitation will fall as snow so we will not have to take into account for a mix or even rain.
As we stated earlier, this is a VERY early forecast so a lot will change between now and Tuesday as our models continue to show differences on the track. However, it is clear that 18” to 24” of snow is NOT an accurate forecast, and anyone’s snowfall totals are a guess at this point in the game. This is why we will refrain from throwing out totals as they would be total garbage 4 days out, but we will say that light to moderate snowfall accumulations do appear likely, especially across the southern half of the state. You can continue to follow the Iowa Storm Chasing Network for the very latest forecast updates and information. All of that can be found on our Facebook page and right here at Iowachase.com.