Saturday Afternoon Thoughts

I am generally off the grid on weekends; many of you know I do actually have other responsibilities… husband, father, children’s ministry guy, youth baseball coach, health care industry volunteer, etc… but being a true weather geek I couldn’t resist taking a peek at some data this afternoon. I won’t go into deep detail here, but here are some thoughts on “Clarence”, the system I named about a week ago.

*The main impact on Alabama will come Monday night into Tuesday.

*Significant rain is likely for the southern quarter of the state, with rain amounts of 1 to 2 inches likely.

*Accumulating snow is likely for some part of the Deep South.

*Placement of the surface low, upper trough, and thermal fields will all determine the snow forecast, and those remain challenging with a late season system like this.

*I don’t think anybody feels comfortable putting a snow accumulation graphic together now; still too early.

*The Canadian global model, the GEM remains the most aggressive for now across North-Central Alabama. We note the NAM and the GFS are moving in that direction, but the ECMWF keeps the main precipitation shield south of here. Climatology suggests a Gulf cyclone like this in early March can being a good 3 to 6 inch snow for somebody, but we simply don’t know where that “sweet spot” will be for now.

*I will have a snow accumulation forecast in place early Monday morning with the regular discussion and Weather Xtreme video; I am sure Dr. Tim will have some ideas tomorrow.

*Seems like many here believe you have to have 32 degrees (F) at the surface before we get snow. Nothing is farther from the truth; the key temperature to watch for a rain-snow line is the freezing temperature at 850 mb, or around 5,000 feet off the ground. You can have a very good snow here with surface temperatures in the 35 to 40 degree range. But, of course, for the accumulation forecast, you have to consider the soil and surface temperatures.

*MOS products from the various models are often useless in this kind of setup, and many of them have to be rejected.

So, I know that doesn’t answer many questions, but we are not in the business of telling people things we don’t know. That will come a little later; stay tuned, and enjoy the weekend!

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