Absolute Vorticity

Getting a snow shower here now...

tron777 wrote: ↑Fri Jan 20, 2023 9:42 am Good morning Tim and JP! Wow! We got NAM'ed for sure with this next system. It is probably 3/4's snow for us down here then some light rain at the end. Precip rate is the key here and that is how you can get it done even with marginal temps. There is no doubt in my mind that temps are going to be an issue for Sunday. But you can certainly get an inch or two of slush on grassy areas / car tops if the precip rate is heavy enough.

Good morning. Yep. Putting a wrinkle into the plans coming to Cincy Sunday and watching the game with my sister. lol Let's see if the rest of the models follows the nam.

man its one of those winters lol . lets see what happens in this next week as far as getting any white stuff. things should transition back to normal weather for this time of year and probably into early Feb

For Sunday, the 12Z RGEM has a slushy inch for the I-71 corridor, couple of inches or so further north. We are really riding the line down this way.

FYI: NCEP continues to have issues so a lot of the US model data is either incomplete or missing. The only website to my knowledge that is not having issues is Pivotal Weather so I am watching the 12Z GFS run coming in on that site right now. Tropical Tidbits, College of DuPage, Weatherbell etc are def having problems.

12Z GFS is still weak for Sunday. Not much precip at all for those north and west of Cincy. This thing falls apart as it moves thru due to no phasing whatsoever until it's well East of us.

Another differencce in Nam/GFS is surface temps on Saturday . GFS 3-5 degrees higher all the way to I70. That will be important because there won't be a big spread in overnight temps as usually occurs because of such weak high pressure

For next week....12z GFS is mainly rain for Cincy then dry slotted. I-70 Crew gets a thumping of snow to rain and then dry slotted. Heck of a dry slot on this run too. Sheesh! Low moves thru here unfortunately. Sure been seeing a lot of that this winter.

Bgoney wrote: ↑Fri Jan 20, 2023 11:02 am Another differencce in Nam/GFS is surface temps on Saturday . GFS 3-5 degrees higher all the way to I70. That will be important because there won't be a big spread in overnight temps as usually occurs because of such weak high pressure

To add... Because of the temp and thermal profile issues, the only way anyone is going to see snow for Sunday is if the precip rate is heavy enough. The GFS doesn't get it done at all. NAM, HRRR, RGEM does. Just one of those things that are a nowcast.

LOL @ the 15Z RAP for Sunday. It shows an advisory criteria event for just about everyone. Too bad the model has such a cold bias IMO. Looks pretty on paper though.

Beyond the storm for Tues night and Wed, we do get into a NW Flow pattern for a while with colder air to work with along with an arctic frontal passage and maybe a clipper like system or two. That looks to be how this month is going to end. So we do have smaller snow chances upcoming even if Sunday and Wed don't work out. There is my positive message of the day for snow lovers.

tron777 wrote: ↑Fri Jan 20, 2023 11:38 am Beyond the storm for Tues night and Wed, we do get into a NW Flow pattern for a while with colder air to work with along with an arctic frontal passage and maybe a clipper like system or two. That looks to be how this month is going to end. So we do have smaller snow chances upcoming even if Sunday and Wed don't work out. There is my positive message of the day for snow lovers.

It's better than this

GEFS is coming in now and for Sunday, a few members give us a slushy inch or two and some very little. Still not seeing one solution or the other locking in on the Ensemble. For next week's bigger storm, we are seeing the usual array of solutions from snow to rain then back to snow. Mainly rain with a wound up cutter, and even a few that have the Apps Track for a classic AV snow storm! I checked the mean and the 850 MB Low tracks right up the River. If you want a monster snow storm, you would want the 850 low to be just SE of your location. GEFS is def SE of the Operational GFS at this time. The ensemble mean would be mainly snow for I-70, and we would see a front end thump of snow down Cincy way with a changeover to rain, then backside snow showers to end the event.

Bgoney wrote: ↑Fri Jan 20, 2023 11:42 am

tron777 wrote: ↑Fri Jan 20, 2023 11:38 am Beyond the storm for Tues night and Wed, we do get into a NW Flow pattern for a while with colder air to work with along with an arctic frontal passage and maybe a clipper like system or two. That looks to be how this month is going to end. So we do have smaller snow chances upcoming even if Sunday and Wed don't work out. There is my positive message of the day for snow lovers.

It's better than this

OMG yes! Anything is better then that! +10 departure at CVG thru 1/19. Only a trace of snow. Awful...

Bgoney that map you just posted Id say is pretty darn accurate. most days were 5-10 degrees above average from what I remember . ( in my area) my guess is the rest of the month is probably going to be closer to avg though. the real question do we see any meaningful snow

tron777 wrote: ↑Fri Jan 20, 2023 10:39 am FYI: NCEP continues to have issues so a lot of the US model data is either incomplete or missing. The only website to my knowledge that is not having issues is Pivotal Weather so I am watching the 12Z GFS run coming in on that site right now. Tropical Tidbits, College of DuPage, Weatherbell etc are def having problems.

i have not looked at the ncep page in years. I would not even know how to use it anymore.

12z CMC is the usual I-71 dividing line for Sunday and then for next week, it is way NW. The low is an STL to Chicago type of track. Essshh...

The OH River, I-71... however you want to say it, seems to be the dividing line and you can see that on the 12Z Euro as well for Sunday's system. So for folks who can mainly stay snow, 1-2" of slushy wet snow I think is possible. Otherwise, a brief thump to rain is the call with little in the way of accumulation. We will all end this event as snow showers late Sunday ending early Mon morning with little in the way of problems.

Well, the Euro goes northwest from it's previous solutions for next week's storm. Still plenty of time for adjustments.

For Wed of next week, the 12Z Euro starts everyone off as snow, but then we flip over to rain. The further north you are, the longer you'll stay snow. The further south you are, the faster you'll flip over to rain. Low tracks from Paducah, KY to Dayton, OH to Western Lake Erie.

dce wrote: ↑Fri Jan 20, 2023 1:28 pm Well, the Euro goes northwest from it's previous solutions for next week's storm. Still plenty of time for adjustments.

I wonder if this system will buck the trend? Minus the Christmas Blizzard, the majority of storms seem to be overamp'ed and as you get closer in time, storms show up weaker and thus will track further SE. Not sure if that'll happen for next week or not. It all boils down to the degree of phasing and wave interaction. The faster it ramps up, the more NW it'll cut and vice versa.

tron777 wrote: ↑Fri Jan 20, 2023 1:32 pm

dce wrote: ↑Fri Jan 20, 2023 1:28 pm Well, the Euro goes northwest from it's previous solutions for next week's storm. Still plenty of time for adjustments.

I wonder if this system will buck the trend? Minus the Christmas Blizzard, the majority of storms seem to be overamp'ed and as you get closer in time, storms show up weaker and thus will track further SE. Not sure if that'll happen for next week or not. It all boils down to the degree of phasing and wave interaction. The faster it ramps up, the more NW it'll cut and vice versa.

Good question. We don't have true Arctic air this time to punch this south and east. The last several years we have seen models trend south and east much more than we used to, so I will not be surprised either way.

dce wrote: ↑Fri Jan 20, 2023 1:48 pm

tron777 wrote: ↑Fri Jan 20, 2023 1:32 pm

dce wrote: ↑Fri Jan 20, 2023 1:28 pm Well, the Euro goes northwest from it's previous solutions for next week's storm. Still plenty of time for adjustments.

I wonder if this system will buck the trend? Minus the Christmas Blizzard, the majority of storms seem to be overamp'ed and as you get closer in time, storms show up weaker and thus will track further SE. Not sure if that'll happen for next week or not. It all boils down to the degree of phasing and wave interaction. The faster it ramps up, the more NW it'll cut and vice versa.

Good question. We don't have true Arctic air this time to punch this south and east. The last several years we have seen models trend south and east much more than we used to, so I will not be surprised either way.

Even though on the 12Z Euro we didn't get the track that we need for a big one here... I did notice that the high over Eastern Canada (North of New England) was stronger. 1032 MB on this run where the 0Z run had it at 1029 MB. That helps in getting the front end of the system as snow. Of course we go over to rain and wash it all away, but it would certainly help out you guys further to the north to remain snow a little longer. Trying my best to remain positive but it's tough!

tron777 wrote: ↑Fri Jan 20, 2023 1:52 pm

dce wrote: ↑Fri Jan 20, 2023 1:48 pm

tron777 wrote: ↑Fri Jan 20, 2023 1:32 pm

dce wrote: ↑Fri Jan 20, 2023 1:28 pm Well, the Euro goes northwest from it's previous solutions for next week's storm. Still plenty of time for adjustments.

I wonder if this system will buck the trend? Minus the Christmas Blizzard, the majority of storms seem to be overamp'ed and as you get closer in time, storms show up weaker and thus will track further SE. Not sure if that'll happen for next week or not. It all boils down to the degree of phasing and wave interaction. The faster it ramps up, the more NW it'll cut and vice versa.

Good question. We don't have true Arctic air this time to punch this south and east. The last several years we have seen models trend south and east much more than we used to, so I will not be surprised either way.

Even though on the 12Z Euro we didn't get the track that we need for a big one here... I did notice that the high over Eastern Canada (North of New England) was stronger. 1032 MB on this run where the 0Z run had it at 1029 MB. That helps in getting the front end of the system as snow. Of course we go over to rain and wash it all away, but it would certainly help out you guys further to the north to remain snow a little longer. Trying my best to remain positive but it's tough!

It's getting to be late January now. This winter is yet another tough one, no doubt.