BLOG: Wintry Mess Leaves Mark
The wintry mess is moving away, but certainly left its mark.
What you got, really depended on where you live...because the state's weather could be broken down into many different zones. Across the lower Eastern Shore this was mainly rain with temperatures in the 40s. Extreme southern Maryland the middle Eastern Shore started as a sleet/freezing rain mix before transitioning over to rain. Along I-95, including Baltimore City, this started as snow, then went over to sleet pretty quickly before going back to a snow/sleet mix for a few hours. Then, it eventually changed to freezing rain and eventually all rain by 3-5 a.m.
North and west of the city, the cold air hung tough and this storm pretty much came to an end before even getting above freezing. This has to do with a concept known as cold air damming. Cold air is more dense and heavier than warm air. If there is nothing to really push the cold air along, or mix it out, then it will get stuck in the mountains while the warmer air spreads northward both east and west of the mountains - essentially, getting dammed up in the mountains.
In this case, we had the low level of cold air hugging the ground while a storm system moved up from the south. The storm was drawing in bands of "warmer" air along the way that was forced to rise up above the colder, denser air at the ground - creating different layers of air in the atmosphere. Anything falling out of the clouds starts as snow, but starts to melt when it encounters warmer layers on the way to the ground. If the layer is thin, the snow only slightly melts - becoming sleet ice pellets. Then, as more warm air starts to build into the storm, the snow completely melts to a rain before freezing on the ground/surface that it encounters - freezing rain. Eventually, when we can get that warm air to work all the way down to the ground, it becomes a plain rain. This storm definitely featured all of the above, and now you can try to visualize all the different factors working on the falling precipitation.
There is only a short break between that storm and the next one coming our way. The next storm is the one that got hung up over the Midwest because of the coastal storm - it stopped the Midwest storm from moving eastward. Now with the coastal storm moving away, the Midwest storm is quickly moving our direction. There will be some rain mixing with snow tonight through tomorrow morning as this moves by. This storm looks to be more of a nuisance than a big weather maker. What we are more concerned with is the temperatures overnight. If they go below freezing overnight, then what is on the ground will freeze up again...and the ground is very wet this evening. It's going to be a very marginal event with temperatures in the metro region dropping to about 31 or 32 degrees, however if we do go below freezing, then icy roads could become an issue again tomorrow morning. North and west of the city, this will be an even bigger concern.
That storm gets out of here tomorrow afternoon and we warm up to ner 40 degrees. Then, yet another storm will be moving our way. Clouds come back in on Thursday and some snow is possible Thursday night into Friday. The early call is that this doesn't look to wind up into a big snowstorm, but could have enough energy for a few inches accumulation. Of course, we will continue to watch it and keep you updated.
Be safe out there!
