Pattern Januworry

[Webberweather53]

The pattern is is setting up nicely for overrunning which is perfect if you want snow. Typically don’t have to worry about a whole lot of mixed bag stuff. And usually a major swath of the southeast gets the snow. It just matters where the rain snow line sets up and everyone north of there from the western south to the southeast score.

Overrunning events are actually synonymous with mixed precipitation, esp ice. The only time you don’t worry as much about mixed precip/ice is during coastal cyclones. Those are of course rare outside the Carolinas

 

[Myfrotho704_]

Overrunning events are actually synonymous with mixed precipitation, esp ice. The only time you don’t worry as much about mixed precip/ice is during coastal cyclones. Those are of course rare outside the Carolinas

Yeah the 18z GEFS really shows that mixed precip would be a issue with shallow cold air at the sfc/warmer air aloft

 

[iGRXY]

Overrunning events are actually synonymous with mixed precipitation, esp ice. The only time you don’t worry as much about mixed precip/ice is during coastal cyclones. Those are of course rare outside the Carolinas

Really ? Our locals Mets always said with overrunning we typically dealt with really tight cutoffs and gradients.

 

[Myfrotho704_]

Really ? Our locals Mets always said with overrunning we typically dealt with really tight cutoffs and gradients.

That applies to Miller A cyclones mostly

 

[Rain Cold]

Yeah the 18z GEFS really shows that mixed precip would be a issue with shallow cold air at the sfc/warmer air aloft

Deeper cold doesn't start to potentially make it near/into the area until the end of the run. The PNA looks to be positive, but shallow. But at least its not showing big negative. If it were a little bit more amped, the model would have shown a huge cold air outbreak for us.

 

[LovingGulfLows]

Really ? Our locals Mets always said with overrunning we typically dealt with really tight cutoffs and gradients.

Think about it. Overrunning means warmer air overriding a shallow cold air mass at or near the surface. As that warm air rises, it warms the column aloft pushing temperatures above freezing while the surface remains at or below freezing. This is exactly how you get ice or sleet.

 

[Webberweather53]

Really ? Our locals Mets always said with overrunning we typically dealt with really tight cutoffs and gradients.

Yes & no they do not tend to have tight gradients in p type. Overrunning events are driven by warm advection + isentropic upglide over a cold low level air mass (i.e. warm/moist “overrunning” a cold low level air mass). These are same processes that drive precipitation during CAD events in the Carolinas which have expensive areas of mixed phase precipitation/ice as well as snow

 

[Mr. Golf]

I know most dont like JB, but he did a good Saturday summary today. Check it out.

Weatherbell.com

 

[Mr. Golf]

I like overrunning events because I like sleet and ice mix. Mainly due to the shallow nature of the air and like Webber alluded to, the isentropic lift over that.

 

[iGRXY]

Yes & no they do not tend to have tight gradients in p type. Overrunning events are driven by warm advection + isentropic upglide over a cold low level air mass (i.e. warm/moist “overrunning” a cold low level air mass). These are same processes that drive precipitation during CAD events in the Carolinas which have expensive areas of mixed phase precipitation/ice as well as snow

I completely forgot about process of overrunning (learned that a couple years ago) and started focusing on the H5 progression of it. I know Miller A’s were also tight rain snow transitions with typically limited to no mixing and Miller B/CAD were tons of mixing with the majority of precip being some form of ice.

 

[GaWx]

Here is the 18Z GEFS 850 mb 11-15 day temperature anomaly map:



Believe it or not, this is the coldest GEFS 11-15 day 850 mb anomaly map in the SE US as a whole since way back on the 12Z 11/26 run and the coldest in the Midwest since at least sometime last winter!

 

[Webberweather53]

Here is the 18Z GEFS 850 mb 11-15 day anomaly map:

View attachment 99189

Believe it or not, this is the coldest GEFS 11-15 day 850 mb anomaly map in the SE US as a whole since way back on the 12Z 11/26 run and the coldest in the Midwest since at least sometime last winter!

You think that’s impressive, just wait another week or so after this, when the cold air over Siberia starts to enter the picture

 

[Mr. Golf]

You think that’s impressive, just wait another week or so after this, when the cold air over Siberia starts to enter the picture

Looks like the wpo is trending negative.

 

[TheBatman]

I don’t mean to be negative but that isn’t that great of a look for the south. Maybe just some cold rain cads in North Carolina. I guess it’s a start for cooler weather

You gotta start somewhere. It wouldn’t take much for us to tap in that shallow arctic..

 

[pcbjr]

There’s a dark lining in every silver cloud for sure.

The shoe is on the hand it fits
There's really nothing much to it
Whistle through your teeth and spit 'cause it's alright
Oh, well, a touch of grey, kind of suits us anyway
That's was all I had to say, but it's alright

I will get by
I will get by
I will get by
I will survive

?

 

[olhausen]

I like overrunning events because I like sleet and ice mix. Mainly due to the shallow nature of the air and like Webber alluded to, the isentropic lift over that.

I don’t like them at all. They eat into the snow totals and it feels like a waste when we have some rare cold air and moisture coming together in the southeast. I will take it though over rain as long as it’s not heavy ZR.

 

[Avalanche]

The shoe is on the hand it fits
There's really nothing much to it
Whistle through your teeth and spit 'cause it's alright
Oh, well, a touch of grey, kind of suits us anyway
That's was all I had to say, but it's alright

I will get by
I will get by
I will get by
I will survive

?

Love it. Their last hit song.

 

[pcbjr]

Love it. Their last hit song.

never knew the Dead had "hit" ... just great music every time out ... best model run I ever did ... 30 years out on the trail ...

 

[Avalanche]

never knew the Dead had "hit" ... just great music every time out ... best model run I ever did ... 30 years out on the trail ...

Touch of Grey and Truckin' both charted. I guess hit, per say, was a bit of a stretch on my part, but having such a long following I felt obliged to call their signatures "hits". As you say, most of their music is appreciated regardless of chart status.

 

[pcbjr]

Touch of Grey and Truckin' both charted. I guess hit, per say, was a bit of a stretch on my part, but having such a long following I felt obliged to call their signatures "hits". As you say, most of their music is appreciated regardless of chart status.

Yes ...