Absolute Vorticity

mainevilleweather wrote: ↑Tue Feb 01, 2022 8:41 pm

tron777 wrote: ↑Tue Feb 01, 2022 8:37 pm Kind of long range still for the HRRR, but 0Z run has N Cincy burbs and I-70 Crew changing over Wed night after midnight thru 6am from NW to SE across the area. For the Metro and CVG Land area from NW to SE in the 6am to 9am time period Thurs.

Looks like another sleet fest model.

Yep. Lots of sleet and freezing rain in our future.

I like all of the thoughts from earlier by everyone. Rain to start for everybody tomorrow, no issues. By late afternoon and evening, the changeover begins in NW counties and slowly moves SE thru the night. Should be down to CVG by Thurs morning, then continue SE from there. 8-12"+ of snow looks good for Eric where he will remains mostly snow with a bit of sleet. More sleet and snow mixed for I-70 Crew frz rain then a lot of sleet burbs to river and probably 2-4" of snow. CVG on south frz rain, a lot of sleet then a couple inches of snow. I mean that was pretty much Bgoney's map which I fully agree with. I can see someone getting 3-4" of sleet cement out of this. A half inch of ice for some of you too. It's going to be an all out mess for everyone to some degree on the forum., We finally have a region wide event lol I think we've got a good handle on this system,. More data to come, but it's really turning into a nowcasting event at this point. Let it ride...

Normally I don't get nervous about winter events. I'd say this one has me pretty stressed out. LOL

Everyone North of the river getting frozen precip by 4am Thurs night on the 0Z NAM.

Frz rain NKY and sleet N of the River by 7-8am Thurs morning.

Nam looks to have a bit more FZ than sleet to start out

Sleet moves into NKY mid morning and ice over the SE. Gonna be a big sleet run NKY to I-70 and heavy snow north of there. Big ice SE Counties. Pretty much the ongoing forecast I think. 3KM NAM coming in a bit colder, changing folks over a couple hours sooner then the operational NAM. Seeing a lot of guidance now bringing the low up into SE KY into WVA. More NW solution is going to pan out it looks like. You would expect a big jump north from the GFS tonight I am going to guess without looking lol Anyway, we're locked and loaded for one messy storm guys.

Still with the 6c 850 temps, oy vay

Nam looks like continued junk for us... Really hope the GFS pulls through or I fear the sleetfest of 22' is our future

mainevilleweather wrote: ↑Tue Feb 01, 2022 9:20 pm Nam looks like continued junk for us... Really hope the GFS pulls through or I fear the sleetfest of 22' is our future

I've already resigned myself to it lol

Alright guys... will catch up in the morning! Please keep the discussion going tonight and do some nowcasting too!

Nbc 4 posted this tonight

tron777 wrote: ↑Tue Feb 01, 2022 9:21 pm

mainevilleweather wrote: ↑Tue Feb 01, 2022 9:20 pm Nam looks like continued junk for us... Really hope the GFS pulls through or I fear the sleetfest of 22' is our future

I've already resigned myself to it lol

I'm starting to get that feeling even up in my hood. If the GFS continues it's northward bump on this evening's run I will officially resign myself to mostly sleet and a couple inches, and that's a maybe, of back end snows. Never underestimate WAA in our area. Yeah, not a strong low pressure system that wraps up, but still it's warm moist air heading north. We've seen this movie before. This is a north of I-70 special more than likely.

tron777 wrote: ↑Tue Feb 01, 2022 5:47 pm I think the map looks great Bgoney! I was going to make a map after dinner but might not really have to after looking at that. Sleet / frz rain is the major precip type esp down here. I-70 Crew can go either way from that to hvy snow. N tier of counties and Eric are locked in!

Yay!

00z GFS rolling.. through hr42 looking a slight tick nw. Didn't look at 850mbs but my skills aren't good enough to properly analyze anyway!

GFS still keeps us in the game. Almost 9 inches with .25 frozen

Take that back 11 inches kuchera, 10.5 at 10:1

Watch has been upgraded to a Winter Storm Warning for most of us-

https://forecast.weather.gov/wwamap/wwa ... %20warning

Ice Storm Warning into Central KY-

https://forecast.weather.gov/wwamap/wwa ... %20warning

Anyone seen the latest NAM? Curious what it is saying

Don;t have any changes from the map of yesterday . Actually a bit more confident with amounts. A smorgasbord of accumulating wintery precip. With the FRZ rain threat biggest for the SE crew and expect ILN to go to Ice storm warning for ILNs southern and eastern most counties

Bgoney, your map looks great. I was just adding about 1 inch of snow to the totals except the northwest area which talked about yesterday has probably the most bust potential low or high. During the height of the second wave late Thursday morning through the evening what will the temps look like is one I am still not quite sure. We know the first push of colder air comes in overnight but where are temps at 12pm Thursday and 6pm Thursday and that one also is a big factor on roads. How long is the period of frz/rain of course is another issue and of course temps when that is happening. Again models have done a decent job and its really been about the thermals and so far the nam seems to be doing a decent job but really that is why that model can be important though it has its problems this time this model has been very important.

Good morning all! I have looked at the text data from the 6Z NAM, GFS and 0Z Euro models. I have no changes either. The post I made last night for timing and Bgoney's map are still perfectly valid. I'd start watching short term guidance and meso scale guidance today along with SPC mesopage. The global models and hi-res guidance are pretty much lock and step. GFS and Euro maybe give you a little more snow on the backside versus the NAM and RGEM where its more sleet and ice related. It's going to be a mess anyway you slice it by tonight for I-70 and NW counties and tomorrow for the rest of us. Friday area wide too as the light snow lingers and things begin to wind down. No one gets above freezing until Sunday afternoon once we get below later tonight.

tpweather wrote: ↑Wed Feb 02, 2022 6:21 am Bgoney, your map looks great. I was just adding about 1 inch of snow to the totals except the northwest area which talked about yesterday has probably the most bust potential low or high. During the height of the second wave late Thursday morning through the evening what will the temps look like is one I am still not quite sure. We know the first push of colder air comes in overnight but where are temps at 12pm Thursday and 6pm Thursday and that one also is a big factor on roads. How long is the period of frz/rain of course is another issue and of course temps when that is happening. Again models have done a decent job and its really been about the thermals and so far the nam seems to be doing a decent job but really that is why that model can be important though it has its problems this time this model has been very important.

Hey TIm, we talked very early on when the NAM first came into range of our event , how even though it was long range NAM , its tendency to sniff out the thermals in these difficult situations are usually better than the globals. A huge red flag for me early on was the GFS showing a foot of snow south of 71 into KY, that just wasn't going to happen with this set-up, so I never considered the GFS amounts, it was just noise.

Good Morning Les and I agree it really a now cast and having folks report in would be wonderful. Sort of funny but the gfs and euro are almost in perfect line for this system while the cmc is more in line with the nam. Thursday afternoon and where does the front stall when the second wave approaches is so key. Again it will be in eastern Kentucky heading towards central Tn. That is where the nam and rgem is showing the thermals still warm enough well north and west of the front to have liquid precip making it to the ground. 20-30 miles will make a difference on Thursday and yes we can use the models as a reference before the system arrives but nowcasting will be so important on Thursday.

Bgoney I agree and my biggest problem I seem to have is temp at the ground during the height of the storm. This concerns me more especially after 2 or 3pm on Thursday as the sun starts its normal decent and this ends the solar output that can help keep surface temps up somewhat.