Absolute Vorticity

Latest thinking from the boys:


A fast-moving clipper system will move southeast across our
forecast area on Sunday. There appears to be enough dynamics and
isentropic lift to bring a chance of snow, with the highest
probability expected along and north of the Ohio River. Current
forecast yields 1 to 2 inches north of the Ohio River, with an
inch or less south. It will remain cold on Sunday with highs
ranging from the mid 20s north to the lower 30s south.

Skies will partially clear Sunday evening as weak high pressure
also quickly traverses east/southeast through the region.
Clouds will increase from the northwest late as another
disturbance moves east into the Great Lakes. Lows will range
from the lower teens northeast to 15 to 20 elsewhere.

On Monday, aforementioned disturbance and its associated
isentropic lift may bring a chance of snow to our far northern
zones. Otherwise, a cold front will be heading southeast into
the region. Southwesterly flow ahead of the front will allow
temperatures to warm into the mid 30s north to the lower 40s
south.

Models agree that the cold front will move southeast through
the region Monday night into Tuesday. However, there remains
differences in how a southern stream s/wv will interact/inject
moisture into the cold frontal boundary. Will forecast a chance
of rain and snow, with likely PoPs possible for the far
southeast. Lows in the mid 20s to the lower 30s will not warm
much on Tuesday (could actually even slowly fall) as CAA moves
into the area.

For Tues... the 18Z GFS has partial phasing / interaction is a bit later so most of the light snow is along and SE of I-71 as a result. 12Z run obv was better with a faster phase.

21Z SREF mean tonight for the Sun clipper has:

CVG - 0.75" of snow
HAO - 1"
MGY - 1.2"
DAY and CMH - 1.3" and 1.4"

No changes from me on the clipper for Sunday. I think 1-2" looks good for the I-70 Corridor. Amounts drop off as one heads south. Dusting to 1" for the N Cincy burbs and nothing to a dusting for CVG and points south. This is pretty much my call on this system.

The Tuesday phaser is not looking good. The thread might be ending early unless guidance changes. Flow looks to fast esp for the northern stream. Models are now wanting to give us a bone towards the end of next week instead of Tues. We'll see on that threat but the Tuesday threat is in trouble. I will say that.

You know it’s bad when CB punts the Tuesday potential

12Z NAM looks decent for CMH - 0.19" QPF for the clipper and DAY gets 0.11" A dusting probably for CVG at best.

The clipper seems to becoming a non-event, like most of this winter so far.

Well, they have been putting brine down the past couple of days. It probably won't happen.

young pup wrote: ↑Sat Jan 22, 2022 11:24 am Well, they have been putting brine down the past couple of days. It probably won't happen.

Good Afternoon and I believe you might be the winner on this system and would not be surprised to see 2-4 inches just because of the ratio

CMH def looking like the best chance at getting out the shovel. 12Z Euro has 1-2" Sunday and another 1-2" on Monday from a second clipper for Columbus. DAY should get an inch or so from both. CVG... a dusting most likely from each. I'm going to change the thread title to dual clippers then that will probably wrap this thread up.

That thread title makes more sense now.

tron777 wrote: ↑Sat Jan 22, 2022 1:21 pm That thread title makes more sense now.

Makes sense Les and I do believe Columbus area has best shot of higher totals. So far the first clipper is a tad further west and stronger than models showed but no sense changing forecast until it really starts to move this way. We know being on the south side of these clippers is a death nil and lucky sometimes to get flurries.

Clipper #1 is a 1016 MB low entering ND from Saskatchewan but it originated in Alberta. This is a true Alberta Clipper. A small compact system moving very quickly. Couple nice areas of snow over ND and SD moving SE to the north and east of the low track. You usually want to be 50-100 miles north of the clipper low track for the best snows. Ideally, you want to be the pivot point. When the system is done dropping SE then scoots east as it rounds the base of the trough. For Cincinnati, the clipper low track for us that's best is usually along or S of I-64. This one looks to track more north closer to us so thus, expecting I-70 on north to have the best snows.

Great Post Les and that is usually the track we need for a decent snow with these Alberta Clippers. I was hoping a stronger push of cold may shift the storm 50 miles south but trend over the past 24 hours has been a tad north but not by much.

tpweather wrote: ↑Sat Jan 22, 2022 1:37 pm Great Post Les and that is usually the track we need for a decent snow with these Alberta Clippers. I was hoping a stronger push of cold may shift the storm 50 miles south but trend over the past 24 hours has been a tad north but not by much.

And the bad thing is... we got our north wish we wanted but the polar jet is still too dominant so it's too fast where the STJ is much slower. Once we lose the +PNA that will change. With a bit of a SE ridge coming back into play, phasing will be easier later this month and esp into Feb. We run the risk of raining but the chances for heavy snow also go up. For now, all we've got are these little skiffs of snow to track.

tron777 wrote: ↑Sat Jan 22, 2022 1:32 pm Clipper #1 is a 1016 MB low entering ND from Saskatchewan but it originated in Alberta. This is a true Alberta Clipper. A small compact system moving very quickly. Couple nice areas of snow over ND and SD moving SE to the north and east of the low track. You usually want to be 50-100 miles north of the clipper low track for the best snows. Ideally, you want to be the pivot point. When the system is done dropping SE then scoots east as it rounds the base of the trough. For Cincinnati, the clipper low track for us that's best is usually along or S of I-64. This one looks to track more north closer to us so thus, expecting I-70 on north to have the best snows.

Dreaming of Feb ‘10. That clipper train was insane.

tpweather wrote: ↑Sat Jan 22, 2022 12:52 pm

young pup wrote: ↑Sat Jan 22, 2022 11:24 am Well, they have been putting brine down the past couple of days. It probably won't happen.

Good Afternoon and I believe you might be the winner on this system and would not be surprised to see 2-4 inches just because of the ratio

Yes, it is beginning to look like that. Hoping it is in and out so all can be cleaned up by early monring Monday. Then get ready for the 2nd clipper.

Trevor wrote: ↑Sat Jan 22, 2022 2:28 pm

tron777 wrote: ↑Sat Jan 22, 2022 1:32 pm Clipper #1 is a 1016 MB low entering ND from Saskatchewan but it originated in Alberta. This is a true Alberta Clipper. A small compact system moving very quickly. Couple nice areas of snow over ND and SD moving SE to the north and east of the low track. You usually want to be 50-100 miles north of the clipper low track for the best snows. Ideally, you want to be the pivot point. When the system is done dropping SE then scoots east as it rounds the base of the trough. For Cincinnati, the clipper low track for us that's best is usually along or S of I-64. This one looks to track more north closer to us so thus, expecting I-70 on north to have the best snows.

Dreaming of Feb ‘10. That clipper train was insane.

I do every February too!

15Z SREF from both clippers:

CVG - 1/2"
DAY - 2.5"
CMH - 3.1"

18Z NAM has the first clipper passing north of I-70 now. Best snows over Lower Mich, N OH, and N IN. I-70 crew should have a snow globe kind of day tomorrow where we won't see a thing in CVG Land until the cold front comes thru with our dusting of snow in the afternoon.

18Z HRRR for the first clipper:

Monday also looking like a snow globe day for I-70 corridor per 18Z NAM. 1-2"

If some folks get hit by both clippers then a 3-5" total would be possible. Thinking ILN's N tier of counties will fall into that realm at this time.

I made it to 33 briefly today! Ground is frozen, every flake will stick. Too bad there won't be much moisture down here the next 60 hours.