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Yesterday and today represent great examples of the tricky business of forecasting freezing drizzle vs. snow/ice crystals. Both soundings valid at 10AM each day from the 12 UTC 3-km NAM. Just as in 'classic' IP/SN vs. FZRA situations, 1-2C aloft makes all the difference. #okwx
The freezing drizzle sounding yesterday had a shallow cloud (few hundred m deep) with cloud-top temperatures AOA 0C, but crucially only reached ~ -5C or so, *just* shy of being cold enough to nucleate the supercooled drops and freeze them (usually beginning around -6C or so).
In contrast, today's sounding of an equally shallow cloud also has cloud-top temperatures above the ~ -6C nucleation temp, but gets cold enough to nucleate and has just enough depth to allow for (pretty terrible) depositional growth, resulting in flurries & minimal impacts.
Naturally these look almost identical in Z on radar (today's precipitation being a bit weaker), highlighting the importance of real-time reports like mPING when the profiles come down to the wire like this.
