1/10-1/12 Southern Slider

[Carvers Gap]

Big trend south.....by the 18z Euro.  There is the new data going into the modeled storm I bet.

[Carvers Gap]

The storm just ran out of gas on that run...break in continuity there by the Euro.

[Carvers Gap]

18z vs 12z.....

 

 

 

[jaxjagman]

5 minutes ago, Carvers Gap said:

18z vs 12z.....

 

 

 

Not as cold?

[Carvers Gap]

4 minutes ago, jaxjagman said:

Not as cold?

Precip went way down....just ran out of gas as it crossed the region.  I looked at 500.  I don't see much different from 12z regarding phase.  Maybe a tad more shear?  However, it has been going down on accums since 6z.  It has always been the weakest.  Waiting to see the ensemble.  May have been a hiccup.  However, with the northern system being sampled now, we may see some changes over the next 12 hours.  I wouldn't think large scale track changes, but we could see the qpf change.

[jaxjagman]

1 minute ago, Carvers Gap said:

Precip went way down....just ran out of gas as it crossed the region.  I looked at 500.  I don't see much different from 12z regarding phase.  Maybe a tad more shear?  However, it has been going down on accums since 6z.  It has always been the weakest.  Waiting to see the ensemble.  May have been a hiccup.  However, with the northern system being sampled now, we may see some changes over the next 12 hours.  I wouldn't think large scale track changes, but we could see the qpf change.

Is the snow map 10:i higher than the Kuchera,might be cutting back on the totals like 5-7:1 maybe,i need to find some better models

[John1122]

The Euro struggled last year with the snow event until 24 hours out. It was weaker and south before finally trending back. It never did catch up qpf wise and missed the 8 to 10+ totals. 

[tnweathernut]

4 minutes ago, John1122 said:

The Euro struggled last year with the snow event until 24 hours out. It was weaker and south before finally trending back. It never did catch up qpf wise and missed the 8 to 10+ totals. 

Good to know.  There’s always a model or two that probably make the pros break out in hives leading up to the event.

[Carvers Gap]

It definitely has been weaker for several storms - GFS/NAM/RGEM have been better with overall the qpf.  I don't like the trend though, but it is one run.  However, with the northern stream energy making it onto the continent, it is possible better sampling will improve the resolution of the forecast.  On to the next run!

18z EPS vs 18z Deterministic.  Pretty rare to see the ensemble have more juice than the operational.

18z Deterministic vs 12z Deterministic

 

[John1122]

This was the Euro last January while every model was showing a big hitter in Tennessee. 

The map here is through 126, but the storm was already in NAM/RGEM range at this time. The Euro suddenly went south and basically whiffed. It spent several cycles trying to recover and eventually did with the path but never with the QPF. 

[tnweathernut]

4 minutes ago, John1122 said:

This was the Euro last January while every model was showing a big hitter in Tennessee. 

The map here is through 126, but the storm was already in NAM/RGEM range at this time. The Euro suddenly went south and basically whiffed. It spent several cycles trying to recover and eventually did with the path but never with the QPF. 

I don’t remember how that storm verified, mainly because I don’t remember any snow from last year.  lol

[John1122]

1 minute ago, tnweathernut said:

I don’t remember how that storm verified, mainly because I don’t remember any snow from last year.  lol

8 to 12 inches Plateau and up the Central Valley of East TN. Far east areas had downsloping issues. 

When the storm was 42 hours from hitting Memphis the Euro got the track correct but the qpf was about 60 percent of what fell. 

The RGEM was probably best on it if I recall correctly, and the ICON was close too. 

[Holston_River_Rambler]

18z EPS members and slps:

 

 

 

 

[John1122]

8 minutes ago, tnweathernut said:

I don’t remember how that storm verified, mainly because I don’t remember any snow from last year.  lol

I believe basically 5-7 in the Mid-State and 3 to 5 in West Tennessee as well. 

[nrgjeff]

The forecast vertical cross sections with time (not distance) that @Knoxtron posted on the previous page are excellent. 

The immediate surface won't hurt Chatty. That warm bubble at 900 mb would be a disaster during the event, but that's mostly before precip. Column is forecast to cool. One can see that really well esp. TYS and TRI. By main event time the column is cool enough. The perfect storm track is why we can accomplish that, rather than have warm air bleed down and up from the bubble and the ground. 

Barring a disaster everything should work out. OK I'm signing off for the night. Happy forecasting!

I love those charts this storm. Most of the time they'd have warm air expanding and piss me off, lol!

[Matthew70]

3 hours ago, Reb said:

Woof woof!!!!!

[ShawnEastTN]

1 hour ago, John1122 said:

The Euro struggled last year with the snow event until 24 hours out. It was weaker and south before finally trending back. It never did catch up qpf wise and missed the 8 to 10+ totals. 

I'm glad you brought that up, I think the Euro really blowing it last year lead to some forecasters who lean heavily on the Euro to really bust on their forecasts probably even WVLT.  I remember having a pit in my stomach all the way to the start of the event of "what if Euro is right."  For that storm the Euro was basically alone, all other major models were much juicer in qpf.  Wonder if we'll see similar this January storm and then the question of why such disparity.  Euro had me at about 1 inch when I got 10 inches.

[TellicoWx]

25 minutes ago, ShawnEastTN said:

I'm glad you brought that up, I think the Euro really blowing it last year lead to some forecasters who lean heavily on the Euro to really bust on their forecasts probably even WVLT.  I remember having a pit in my stomach all the way to the start of the event of "what if Euro is right."  For that storm the Euro was basically alone, all other major models were much juicer in qpf.  Wonder if we'll see similar this January storm and then the question of why such disparity.  Euro had me at about 1 inch when I got 10 inches.

I despise that storm lol...ruined my whole winter. Was exact opposite here..was showing a decent event and watched rain falling 90% of the event lol.

[ShawnEastTN]

7 minutes ago, TellicoWx said:

I despise that storm lol...ruined my whole winter. Was exact opposite here..was showing a decent event and watched rain falling 90% of the event lol.

Right the cutoff was extreme.  Sweetwater had a few inches but as you continued East toward Tellico it dropped completely off.

[*Flash*]

Yeah, it feels weird saying but I’m not sure I’m buying the Euro at the stage. Almost to the 60 hour threshold so hopefully higher resolutions will start to unveil a clearer picture. FWIW, SREF Plumes have a 3.22” mean for BNA.

[Scottie16]

Right the cutoff was extreme.  Sweetwater had a few inches but as you continued East toward Tellico it dropped completely off.

I had 11 in sweetwater but soon as you got halfway towards Madisonville it dropped to a dusting.


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[ShawnEastTN]

6 minutes ago, Scottie16 said:

I had 11 in sweetwater but soon as you got halfway towards Madisonville it dropped to a dusting.


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I didn't realize Sweetwater got that much, I knew they had snow as I had to get on I-75 a few days later at sweetwater to go to Knoxville because I couldn't go to I-40 the way I normally would because it was just still too bad locally where I live.  I have a friend in Madisonville that said they got virtually nothing so knew the line was between the 2 somewhere.

[Scottie16]

I didn't realize Sweetwater got that much, I knew they had snow as I had to get on I-75 a few days later at sweetwater to go to Knoxville because I couldn't go to I-40 the way I normally would because it was just still too bad locally where I live.  I have a friend in Madisonville that said they got virtually nothing so knew the line was between the 2 somewhere.

I think sweetwater was right at the edge to be honest. Some of the biggest flakes I’ve witnessed.


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[Scottie16]

But you’re correct Shawn, the picture below is my son who was at his mom’s during the snow. She lives in Madisonville.


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[Scottie16]

I learned something I didn’t know during the big snow last year, that when heavier flakes fall over the smaller flakes it compacts the snow making the accumulation seem smaller. It also can melt it causing a solid sheet of ice. Couldn’t get out of my driveway for three days.


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[John1122]

0z HRRR looks pretty similar to where the 18z GFS was at the same time. 

[Scottie16]

Last one, I promise


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[ShawnEastTN]

Just now, Scottie16 said:

Last one, I promise


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It was a great event, for me it was basically an all day mostly light snow event.  Literally early morning to late night just kept falling.  Never really got heavy for me just really long duration.

[Carvers Gap]

18z Euro AIFS looks very similar to 12z in terms of its qpf.  Knocks about 0.05 off across the board, but not as drastic as the 18z op.

[Scottie16]

It was a great event, for me it was basically an all day mostly light snow event.  Literally early morning to late night just kept falling.  Never really got heavy for me just really long duration.

It wouldn’t be a grand thing but I wish we could witness a back to back event like that. I lived in Florida most of my life and when I saw those big flakes coming down you couldn’t keep me inside.

Like you and Tellico said, The cutoff was so extreme.


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