Many of you are watching the developing story about the winter storm that is expected to affect parts of the Southeast this coming week, especially Tuesday and Wednesday. While the situation is still evolving and will continue to change over time, the models are coming into more agreement on when and where the storm is likely to cause the greatest impact. The axis of snow in the blended models is now a little north of where it was being predicted yesterday and earlier today (see map below) and the timing of when the storm will move through the area has slowed down a little, so that while it is going to be moving through Alabama late Monday into Tuesday, the precipitation in Georgia is most likely to start sometime during the day on Tuesday and it may be late Tuesday afternoon before we see much precipitation there, although there is still disagreement in the individual models when the precipitation will arrive. That reduction in the speed of the storm will also delay the onset of winter precipitation in South and North Carolina. The storm will also bring winter weather to the East Coast, especially if a low develops along the coast and moves northward.

It is not known how far north the snow will get in this storm compared to the one last week, and northern parts of Alabama and Georgia may not get any precipitation at all, or they might get smaller amounts of snow. If they get no snow there is little chance of moisture later in the week, which could add to drought conditions there. Areas to the north of the main snow belt are not too likely to get any freezing rain and so power outages are less likely there than last time.

Areas south of the main snow band will see a mix of snow, sleet, and freezing rain. Any liquid precipitation that falls is likely to freeze on contact with the ground since it is likely to be below freezing at the surface. The areas farthest south may just see a cold rain, but with such cold temperatures any wetness on the surface of roads is likely to freeze quickly once temperatures drop below 32 F in the evening, if it even gets above freezing. As it stands now, the area with the highest likelihood of freezing rain is in northern Florida, but it is possible farther to the north if the track of the low shifts northward.

Precipitation of all types is expected to continue through Tuesday night into Wednesday morning. Some of the models have all of the precipitation out of Georgia by sunrise on Wednesday, while others keep it in the southeast part of the state for a few more hours. Temperatures will continue to be frigid, so any snow or ice that melts during the day is likely to refreeze once the temperature drops below 32 F again, leading to treacherous black ice on roads and bridges until temperatures warm up again and the ice melts.

Remember that these forecasts will continue to change as new model runs come in. The high-resolution models that are used in short-term forecasting are just starting to come in range of when the storm is expected to impact Alabama and Georgia, so we should get more clarity on timing, type, and amount of precipitation in the next day or two.

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