WINTER WEATHER ADVISORIES

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MORE WINTER WEATHER

The NWS in the Quad Cities has issued a winter weather advisory for for the southern quarter to my area from 9:00am to 9:00pm Saturday. Finally, you guys in the south get a chance to share the white gold! I've been feeling for you.

This is the official NWS forecast and I think overall they are in the ballpark. The exception is in the advisory area from near HWY 34 south. I think the potential is there for amounts more in the 2-4" category. The only concern I have is how far north the snow band gets. There is some very dry air in place that will make a sharp cut-off to the northern extent of the snow. Right now that appears to be very close to HWY 30 so that's roughly where the 1" line stops. That could end up closer to I-80 if the dry air is a bit stronger. From there south amounts gradually increase into the advisory zone.

Here's the latest snowfall outputs from the various models. These are not forecasts, just raw model guidance which is what we blend to make forecasts. I have used the Kuchera method which takes into account the snow ratios which should be closer to 20:1 than the standard 10:1. That's due to the very cold air the snow will be falling into. That should make for some nice powder that will fluff up nicely. It's easy to shovel too!

You will notice models have a good handle on the heavier snow band in the south but vary some on the northward fringe. That's the dry air issue mentioned above. I'll have more in my later posts but wanted to get this out there for consumption.

THE 3K NAM

The 12K NAM

The Canadian GEM

The HRRR, it's the furthest north and is an outlier. Either it's onto a trend or its going to bust north of I-80

The GFS

This is the EURO but I don't like the handling of the snow ratios on the site I use which means it might be too heavy and a bit far north.

That's enough for now. (For many of you enough for the rest of winter!) Until next time, roll weather...TS