January 23-25th Winter Wx

[MattW]

Euro also seems to have dropped Atlanta temps. Last run I saw had them not get higher than 37. Earlier we were pushing 60.

 

[Rapideswx]

The latest GFS run shows around 2" of ice in my area (central LA)! Kind of doubt that happens. NWS LCH and local meteorologists are forecasting close to a quarter of an inch.

 

[Psalm 148:8]

00Z NAM time.. yall post the good, bad and ugly..

 

[TVILLE96]

Anything and everything expected here!!. Models and weather forecasters have absolutely laid eggs here! The post mortem on this weekend will be fabulous to see!

Give it two more years, the models will be dead accurate once AI has had more time with it.

 

[N4GK]

Give it two more years, the models will be dead accurate once AI has had more time with it.

AI is only as good as the people who program it. And seeing as humans are a very flawed species, so will AI be.

 

[Blountwolf]

Hoo boy... HRRR coming in colder Friday night. I don't like that. Birmingham below freezing for 4 or 5 hours now.

 

[N4GK]

Hoo boy... HRRR coming in colder Friday night. I don't like that. Birmingham below freezing for 4 or 5 hours now.

View attachment 50171

Thankfully, it will turn to rain late afternoon, Saturday.

 

[TVILLE96]

AI is only as good as the people who program it. And seeing as humans are a very flawed species, so will AI be.

Weather forecasts will be one of the true tests or measurements of how well AI works. When you hear all the hype about AI, just look at the outcomes of forecasts and this will tell you how good it is.

 

[The Colonel]

NAM looks slightly more “diggier” through 24. Little bit higher pressure through Ark/Tn/MS/AL by an isobar.

 

[NorthGaWeather]

FFC geographical area is insane. Macon use to have a NWS should still be there. Some of the wording from FFC forecasts are very confusing especially when you live in the Atlanta metro.. it's ridiculous that Alabama and South Carolina each with about 5 million people have three national weather service offices. Georgia has one with 12 million people.

To my knowledge, the old WSO’s were at Athens, Augusta, and Columbus.

 

[bckhd2]

Think ATL will escape the worst here. Blairsville, Gainesville, Athens, all looking bad.

 

[Clancy]

Ice Storm Warnings are out now and have been expanded for parts of Mississippi and Tennessee, as well as far NE/SE corners of Louisiana and Arkansas, respectively.

 

[sak]

Hoo boy... HRRR coming in colder Friday night. I don't like that. Birmingham below freezing for 4 or 5 hours now.

View attachment 50171

this is no big deal. precip probably won't reach Birmingham until mid to late afternoon.

 

[MikeP]

Man there is a ton of snow on the ground up north. But after this weekend, about 1500 miles from north to south will be covered. It's gonna get cold....

 

[Psalm 148:8]

Something gotta give here! I’ll let yall know if I get an icenado Sunday night!

 

[Blountwolf]

this is no big deal. precip probably won't reach Birmingham until mid to late afternoon.

I'm watching model trends - the previous full HRRR run only had BMX below freezing at 5am, this one was 5 hours worth.

 

[Blountwolf]

NAM is pretty status quo - big warm nose, CAD causing mischief.


BlountWolf Alabama Ice Shield holding... (hat tip to psalm for reminding me of the Rob Smith Snow Shield from earlier on the board. Like... way earlier. Like... we're old, y'all.)



NAM is not nice to Mississippi. Yuck.

 

[Blountwolf]

Man there is a ton of snow on the ground up north.

There sure is. It's enough to give one pause - Cold air advected out of a snow-covered Midwest arrives colder and denser than models often predict. That can reinforce surface highs, strengthen cold air damming farther east, and shift precipitation types southward. It's one of the classic reasons forecast temperatures are lower than predicted. Will they be? We'll see. I confess, over the years I've gotten nerdy to the point I enjoy the watching more than whatever ends up happening exactly at my house.

 

[sak]

There sure is. It's enough to give one pause - Cold air advected out of a snow-covered Midwest arrives colder and denser than models often predict. That can reinforce surface highs, strengthen cold air damming farther east, and shift precipitation types southward. It's one of the classic reasons forecast temperatures are lower than predicted. Will they be? We'll see. I confess, over the years I've gotten nerdy to the point I enjoy the watching more than whatever ends up happening exactly at my house.

i don't know how well models will actually account for it... but i'm sure these sophisticated models take into account snowpack. they might overestimate its impact, even. some of the deterministivc model runs for temperatures are outrageous. 10-20 below zero into missisippi/alabama/georgia/eastern north carolina seems outrageous and i have to wonder if it is overestimating the impact of a snowpack on temperatures.

 

[Blountwolf]

i don't know how well models will actually account for it... but i'm sure these sophisticated models take into account snowpack. they might overestimate its impact, even. some of the deterministivc model runs for temperatures are outrageous. 10-20 below zero into missisippi/alabama/georgia/eastern north carolina seems outrageous and i have to wonder if it is overestimating the impact of a snowpack on temperatures.

The ECMWF generally handles these feedbacks better than the GFS. Its land-surface and boundary-layer schemes tend to preserve cold air longer over snowpack, which improves downstream temperature forecasts. The GFS has historically been quicker to erode snow-modified air, especially when southerly flow begins. That the Euro is the one showing the strong warm nose beating out that denser cold air means you may very well be right - there may have been some overcorrection there too.