Absolute Vorticity

I am going to go ahead and get the thread started for discussing the clipper due in sometime on Monday ending Monday night. Clippers are usually quick hitting 1-3" systems. This one will have high ratios to work with with temps in the low to mid 20s for the event (as it stands right now). Current QPF is 0.10 to 0.15" The question for us is... how much of a dig can we get? Will the current blizzard get out of the way enough so this thing can dig more and get a little help from the Gulf. Or, will it shear out and weaken as it comes in for very little snowfall.

Good Ideal to start the thread Les. What makes an overachieving clipper is usually a good southwest wind. Going to be interesting to see if the clipper is just a little to fast and we are not getting the best southwest flow. Get a piece of energy and a strong southwest wind and that is when these clippers can get you a 3-6 inch snow. This is not a prediction but what can happen if everything falls in place. What the clipper will do though is keep the colder air in area longer than the models predict which I mentioned i another section.

tpweather wrote: ↑Fri Dec 23, 2022 8:18 am Good Ideal to start the thread Les. What makes an overachieving clipper is usually a good southwest wind. Going to be interesting to see if the clipper is just a little to fast and we are not getting the best southwest flow. Get a piece of energy and a strong southwest wind and that is when these clippers can get you a 3-6 inch snow. This is not a prediction but what can happen if everything falls in place. What the clipper will do though is keep the colder air in area longer than the models predict which I mentioned i another section.

I agree. I don't see us getting above freezing until Tues or perhaps Wed.

Currently ILN has a 30% chance for the clipper effects for here in Greenville e.g.

MVWxObserver wrote: ↑Fri Dec 23, 2022 8:41 am Currently ILN has a 30% chance for the clipper effects for here in Greenville e.g.

Same here in CVG Land. Pretty typical POPS for an event that is still 3 days out.

Starting to get within the NAM's range now. 12Z run keeps it intact much longer before weakening and it digs a little better too. Hopefully that will be the trend with this one. QPF ending at 7pm Monday at CVG is 0.17" and it's not quite over with yet.

I wouldn't mind adding a few more inches before we torch.

I guess we will see if the pattern resets in January for more snow.

Nice little clipper and on this run a little stronger and further southeast. My guess is once the clipper passes we finally hit 32 late Wednesday and then have a 3 or 4 day milder spell but models never gets the temps correct when there is snow cover to melt. Tuesday-Thursday I take off at least five degrees from the highs models show today and then by Friday we may get near 50 but chances of rain go up. At least we have one more system to follow and then I am heading to SC and will back probably on the 3rd or 4th of January

Same QPF from the 12Z RGEM accept it is S of I-64 in KY. The low is a bit too far south on this particular run for us.

12Z GFS continues to offer up a nice solution giving CVG 0.20" of QPF.

12Z CMC has about 0.15" QPF along and SE of I-71 with 0.20" North and Western sections of our CWA.

12Z GEFS QPF Mean is about 0.15" as well for the area.

12Z Euro continues to have the lowest QPF totals due to a weaker system overall and less digging vs the Canadian and American models. 0.09" for CVG when the rest are in that 0.15 to 0.20" range. We'll see how the trends go moving forward!

Good Afternoon and may need to get the shorts out as my temp has hit -3. We have all the 3 major models in for the clipper and again 3 days away but leaning towards the lower totals and weaker system atm. If this system would slow up by 12-24 hours I would tend to lean on the higher totals. Yes we will still be very cold but how much warmth and how quickly will the return be out of the southwest. Still need that temperature difference to get a really nice system but again the ratio's will help. So this early in the game 1-2 inches seems about right and probably leaning on the lower end unless this is slower in nature getting here then I would probably be a little higher

My prelim call is 1-3" so we're in sync basically Tim at this time. Good middle of the road approach right now.

tron777 wrote: ↑Fri Dec 23, 2022 1:50 pm My prelim call is 1-3" so we're in sync basically Tim at this time. Good middle of the road approach right now.

Perfect Les

So far the Indy NWS is quite high on the clipper for Monday. They do mention that it has not been fully sampled but expect a 20-1 ratio and though not a forecast 2-4 is showing up in the data

tpweather wrote: ↑Fri Dec 23, 2022 3:09 pm So far the Indy NWS is quite high on the clipper for Monday. They do mention that it has not been fully sampled but expect a 20-1 ratio and though not a forecast 2-4 is showing up in the data

Heavier amounts will be to our West / NW because the clipper is weakening as it moves into our area. This idea has been showing up for the last few days. Hope that changes.

tron777 wrote: ↑Fri Dec 23, 2022 3:13 pm

tpweather wrote: ↑Fri Dec 23, 2022 3:09 pm So far the Indy NWS is quite high on the clipper for Monday. They do mention that it has not been fully sampled but expect a 20-1 ratio and though not a forecast 2-4 is showing up in the data

Heavier amounts will be to our West / NW because the clipper is weakening as it moves into our area. This idea has been showing up for the last few days. Hope that changes.

Should be interesting and I agree about the ratios which I thought would be high but was just wondering about the track of course and when the system arrives. More to look at this weekend and free on Saturday except football but Sunday will be family all day long

Louisville going with the lower end around 1 inch.

tpweather wrote: ↑Fri Dec 23, 2022 3:16 pm

tron777 wrote: ↑Fri Dec 23, 2022 3:13 pm

tpweather wrote: ↑Fri Dec 23, 2022 3:09 pm So far the Indy NWS is quite high on the clipper for Monday. They do mention that it has not been fully sampled but expect a 20-1 ratio and though not a forecast 2-4 is showing up in the data

Heavier amounts will be to our West / NW because the clipper is weakening as it moves into our area. This idea has been showing up for the last few days. Hope that changes.

Should be interesting and I agree about the ratios which I thought would be high but was just wondering about the track of course and when the system arrives. More to look at this weekend and free on Saturday except football but Sunday will be family all day long

I'll be in family mode sometime this evening and tomorrow. More free time on Christmas Day and next week.

One last post on this system and checked with many of the NWS to see how they feel about this system and really Indy is the highest and folks in Louisville,Paducah and also in Iowa are not high on totals. The latest Nam looks wonderful for the local area but again we need to have this looked at once again on Saturday.

Another run Tim with near 0.20" of QPF. If we can get that much out of the deal, 1-3" with isolated 4" would be the call. We'll see how things shake out.

One of things to watch with the clipper is how amplified will the jet be so we'll know how much room it has to dig. A system will be crashing into the West Coast as we lose the +PNA so the clipper will only be able to dig so much. If the timing of that Pacific system is delayed any, it would bode well for us. If it speeds up, then not so much. Also... how quickly does that big low form the current system move out so heights can rise a bit ahead of the clipper. That would also help. These are the players on the field for this system.

18Z RGEM is a good example of bad timing. Pacific system is a little faster so not as much digging from the clipper so it weakens faster and starts shearing apart. Further south too since it is a weaker system overall. Light snow River on south only. S of I-64 for an inch or two possible. inch or less S of the river in our CWA. So a lot of it will depend on how strong the clipper is once it is sampled better and how quickly the Pacific system crashes into the Coast.