Winter WX January 29-30 Southeast Event

[rolltide_130]

Somebody somewhere said Clipper systems tend to usually underperform on snowfall totals. I don't remember who said it exactly, but they've been proven right before and it looks like that may happen again.

 

[AL_ham_op]

Oh, this is pitiful. At least I'll have a pretty drive on my way to class in the morning. I'm betting that things aren't going to close until first thing in the morning if at all.

 

[Richardjacks]

The hrrr is a good bit faster with the cold air.

 

[RF16Gold]

Calhoun County, Oxford, Jacksonville, and Faith Christian in Anniston all closed tomorrow.

 

[Kory]

The hrrr is a good bit faster with the cold air.

I'm seeing rates of 1-2" an hour in West AL and East MS with changeover. That will easily collect on surfaces.

 

[skelly]

I'm concerned about ground temps. It's 57 degrees and very sunny here right now. Can they drop fast enough?

Lot of moisture in the ground still.

 

[darkskys25]

The hrrr is a good bit faster with the cold air.

I'm seeing rates of 1-2" an hour in West AL and East MS with changeover. That will easily collect on surfaces.

 

[Kory]

Lot of moisture in the ground still.

Which is why runoff will be a problem (with initial rain before changing to snow)...and then temps drop below freezing.

 

[Kory]

No change on the Euro...1-2" hit across the 20/59 corridor. 17z HRRR keeps with the heavy snow with changover...temps dropping to near freezing.

 

[AL_ham_op]

I don't know what everyone else is thinking but I have a sinking feeling the temps are going to be too high for this. It's almost 60 today and I just don't see the temps dropping fast enough for this to really do much more than cause some bridge icing. Not too hopeful for snowfall at this point.

 

[Blizzard1]

AL_ham, getting the temp down enough to snow should not be an issue except the final accumulation totals. The fact that it is 60 today is not unexpected. The front should be a game changer in and of itself and it will snow. If the bursts are heavy enough it will even accumulate before it reaches freezing(air temp) on some surfaces. The bigger question is where the sub-freezing air temps make it to cause the icing concerns on the roads.

Thanks to all of you posting model updates by the way...

 

[Richardjacks]

AL_ham, getting the temp down enough to snow should not be an issue except the final accumulation totals. The fact that it is 60 today is not unexpected. The front should be a game changer in and of itself and it will snow. If the bursts are heavy enough it will even accumulate before it reaches freezing(air temp) on some surfaces. The bigger question is where the sub-freezing air temps make it to cause the icing concerns on the roads.

Thanks to all of you posting model updates by the way...

Yes, the real issue here is how much precip is behind the front. This is based on amount of surface convergence, and divergence aloft that we typically see with a positively tilted trough. This is a very energetic system and that could be underplayed by models.

 

[Evan]

I wouldn't put too much stock into that nasty run of the NAM. I actually think the Bham area and to the west will still be one of the best areas. I think the NAM was either too slow with the cold air moving in or too fast with the precip moving south.

Still, there's been a few times recently the NAM did very well with winter systems.

I'm always suspect of big model changes 24 hours from an event because often times things adjust back closer to the solution presented earlier. We will see, but I think the most recent 1-2 NAM runs were way too fast. HRRR ensembles give me a lot of hope as do the last run of the operational HRRR.

It is very difficult for models to nail the timing on events like this, so verifying model guidance against current observations and conditions is key.

 

[Blizzard1]

Yes, the real issue here is how much precip is behind the front. This is based on amount of surface convergence, and divergence aloft that we typically see with a positively tilted trough. This is a very energetic system and that could be underplayed by models.

Thanks for the info Mr. Jacks...you and Kory, et al have been doing really well with the updates! It does seem like a very dynamic system compared to what we are used to with clippers and I am looking forward to any convective bands we might get. Do you see any opportunity for say thunder-snow with this event given the dynamics?

 

[Gail]

My son attends an early college high school in Columbus, MS, and they’ve cancelled classes for tomorrow!

I’m still waiting to see what my other son’s school and the Air Base does (I work on base). Crossing my fingers for a snow day for us also.

 

[Kory]

Something of note off the HRRR...mid level lapse rates over the region of 6.5-7 C/KM. Maybe a clap of thunder with the snow?

 

[northeastatlwthrguy]

kory bud how is it looking east of you in ATL?

 

[Jacob]

18z NAM is running, and it's another bad run for central AL. It is slower with the surface cold, and still has it 37 in Birmingham at 12z as precip is moving out. Shows a few spotty accumulations where the heavier snow changed over, but overall little to nothing.

Oddly, it's slightly faster with the arrival of the cold air aloft, but slower at the surface.

 

[NorthGaWeather]

I'm not too confident in major impacts across the Atlanta Metro attm. Maybe that will change as we get into the evening. Model trends, soil temps, cold air/precip questions are faaaaaar more prevalent across our area. You guys in Alabama, Tennessee, and Far North Georgia should have a decent event.

 

[AL_ham_op]

18z NAM is running, and it's another bad run for central AL. It is slower with the surface cold, and still has it 37 in Birmingham at 12z as precip is moving out. Shows a few spotty accumulations where the heavier snow changed over, but overall little to nothing.

Oddly, it's slightly faster with the arrival of the cold air aloft, but slower at the surface.

This is what I'm going with. I just don't see the temps getting cold enough quickly enough.