re: Snow Tease for Baton Rouge (Saturday) UPDATE (1/20)

What I don't understand is the difference with how different models advance the freezing line into S. LA. The NAM has the freezing line digging NE to SW across the Southern portion of the state, dropping below freezing well in advance of the second round of rain.

The GFS, though, advances the freezing line from W to E, and never really gets widespread freezing temps across the until the rain has moved out, almost like a traditional front passing through.

NAM and GFS look pretty much the same with the 12z run. The only difference is GFS is just 4-5 degrees warmer. Front passage and moisture setup is identical. Like every deep south winter event it will come down to those surface temperatures dancing around freezing and we won't know exactly what they'll do until it happens.

Another question

Even if the temp is at freezing or just slightly below, isn’t ground temperature far warmer and no ice would form on the actual ground?

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What I don't understand is the difference with how different models advance the freezing line into S. LA. The NAM has the freezing line digging NE to SW across the Southern portion of the state, dropping below freezing well in advance of the second round of rain. The GFS, though, advances the freezing line from W to E, and never really gets widespread freezing temps across the until the rain has moved out, almost like a traditional front passing through.

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The NAM has colder surface temps ahead of the rain, then drops temps to freezing right as the rain arrives. That obviously results in an icy surface which screws up daytime heating, resulting in an advancing freeze line along the precipitation.

The GFS has warmer surface temps ahead of the rain so the rain never freezes, thus allowing daytime heating to begin. Once the precip and clouds move out, temps fall.

Nobody knows which is going to be right. The bottom line is this… multiple models have been sniffing some sort of icy conditions somewhere in the gulf south off and on for a week now. They’ve been taking turns with which sees frozen stuff and which one doesn’t. The overall loose trend is that someone may see freezing rain/sleet but it’s impossible to tell who or how likely it is.

That is going to be a mess. It seems like we are going to get something at this point with the moisture and cold temps. Lets hope that some how snow develops rather than freezing rain or ice. I think we would have a lot fewer power outages with snow. If one good thing could have come out of Ida in my area is maybe it reduced some damaged that could be caused by whatever winter weather we get.

12z GFS Ensembles are still very confident

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That is going to be a mess. It seems like we are going to get something at this point with the moisture and cold temps. Lets hope that some how snow develops rather than freezing rain or ice. I think we would have a lot fewer power outages with snow. If one good thing could have come out of Ida in my area is maybe it reduced some damaged that could be caused by whatever winter weather we get.

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Who will be new HC for ya'll?

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Who will be new HC for ya'll?

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No idea, but if I had to guess they will frick up the hire.

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If one good thing could have come out of Ida in my area is maybe it reduced some damaged that could be caused by whatever winter weather we get.

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This is a fact. The 2021 snow and ice storm in north LA didn't have many power outages because Laura came through and wiped out the weak trees 5 months earlier.

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NAM is getting the axe in the somewhat distant future. They're combining HRRR, NAM, and GFS into one mega jack of all trades GFS that shows high-res and global scales. RIP NAM

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I'm hoping they differentiate between products with a mean run for a while. Treat each like an ensemble. Surely they will. If not, we're likely to see a mess that takes a while to work itself out.