Absolute Vorticity

Wouldn't shock me a bit to see a tick back west, enough to get moisture back into our area i'm not sure

Definitely a tough forecast with a high bust potential either way as in light precip or heavy precip. Again, the timing of the phasing will make us or break us.

tron777 wrote: ↑Thu Dec 14, 2023 4:54 pm Definitely a tough forecast with a high bust potential either way as in light precip or heavy precip. Again, the timing of the phasing will make us or break us.

Both the Euro and the GFS give us an inch from the northern low actually. It slows down over us as it becomes absorbed by the stronger low.

The 18z GFS gave us Bgoney’s tick west, but no real changes to the outcome. I still expect a further westward shift. How far is TBD.

Nice wrap-around snow showers on Monday night as well.

Trevor wrote: ↑Thu Dec 14, 2023 5:47 pm Nice wrap-around snow showers on Monday night as well.

It's a shame that final piece that brings in the wrap around snow showers couldn't get more involved. Yes... I am always rooting for the most weeniest solution possible!

18Z GEFS Mean has 0.62" for precip totals. That is the mean from all Ensemble members.

52 and 23 for cvg today

Good Evening and another cold night in store. This has been a nice high sitting over us and if we would have had snow on the ground here and further north this could have thrown some temps at least in the single digits. Hopefully these highs continue through the winter to bring in some decent cold. Tricky forecast for the weekend as you have 3 pieces of energy trying to get together. The first two over the Ohio Valley late Saturday into early Sunday. That is where you may get a decent .25-.5 but probably a narrow area. Then how does the southern energy hook up with the northern energy and that is where the biggest bust are likely. How strong is the northern one because this one can make or break on precip amounts as well. The further west and stronger the system becomes will also set up the table for maybe the first accumulation later Monday in the form of some decent snow showers but again lets see how things pan out. A few cold days after that and then we get mild but nothing out of hand later next week. Some signs that another cold shot around the 23rd or so. We have time for that but would be nice to have temps at least somewhat to help the Christmas mood.

NEW This Week in Weather from DT that he posted last night:

Bgoney wrote: ↑Thu Dec 14, 2023 6:34 pm 52 and 23 for cvg today

That large high over us, combined with the ongoing drought, is sure making for some nice temperature ranges.

tpweather wrote: ↑Thu Dec 14, 2023 6:39 pm Good Evening and another cold night in store. This has been a nice high sitting over us and if we would have had snow on the ground here and further north this could have thrown some temps at least in the single digits. Hopefully these highs continue through the winter to bring in some decent cold. Tricky forecast for the weekend as you have 3 pieces of energy trying to get together. The first two over the Ohio Valley late Saturday into early Sunday. That is where you may get a decent .25-.5 but probably a narrow area. Then how does the southern energy hook up with the northern energy and that is where the biggest bust are likely. How strong is the northern one because this one can make or break on precip amounts as well. The further west and stronger the system becomes will also set up the table for maybe the first accumulation later Monday in the form of some decent snow showers but again lets see how things pan out. A few cold days after that and then we get mild but nothing out of hand later next week. Some signs that another cold shot around the 23rd or so. We have time for that but would be nice to have temps at least somewhat to help the Christmas mood.

I'm pretty much at those numbers with .25"- .75" (DAY,CBUS,CVG) for reasons talked about earlier. ATM i feel like amounts of an inch would be overachieving for this particular set-up . Winds remain out of the SE until late Sat early Sun and with dry air , low DPs to overcome some of that modeled QPF will get eaten up . Of course if the coastal low has a big shift west and can muster a push of backlash moisture into the region its a different ballgame

I also agree with 0.25 to 0.50" for much of our local area. Lightest NW, heaviest SE of course as we all know in this set up. Best case scenario is we get the proper phasing then you'd be looking at 1-2" of rain, but we just don't know this far out. I'd still look for some changes in the modeling for the next 1-2 days. Timing attm for the best rains is Sat night into Sun morning. If we see the proper phasing then Sunday is a washout.

18Z Euro has 0.89" of rain at CVG with the bulk of it coming Sat evening thru Sun morning.

Takeaways from the 00z guidance:

-it appears any westward shift with the main low has haulted; we may see another bump west but probably not enough to add to our precip totals
-GFS is the heaviest with 0.75-1.00" across the tri-state
-Euro 0.50"
-Canadian 0.34"
-NAM <0.25" (the driest model)

My forecast has been 0.50-0.75" and that still looks good, though if the NAM is setting a trend for future runs the amounts would need to be bumped down a bit.

Good Morning and another cold and crisp leading to a sunny and nice afternoon. The next 3 days is more of a tweaking of the forecast and everyone should get some rainfall but can we get higher amounts. Still believe a period later Saturday into early Sunday gives us the best shot of steady rains and going 0.25-.5 for most though a few folks may get less and few more but only slightly. The storm on the east coast looks to stay near or just off the coast and most likely take the energy we have here and transfer it to that storm. This most likely will shut off much of the rain locally during the afternoon. The east coast storm looks nice with some very strong winds and heavy rain later Sunday into Monday. I believe you may see this kind of storms several times over the winter but with colder air and could be one nice blizzard. Later Monday another piece of energy dives down into the Ohio Valley but the further east the main storm heads the less likely of snow showers locally. I still believe we are on the edge and should see a snow shower or two and maybe even whiten the ground briefly. Then we stay cold for a day or two and milder air returns late in the week.

Then Christmas weekend starting on the 23rd and will we see another system or does it wait until the 26th of so. To early and you will see some changes after this major storm on the east heads northeast. Still looks like the last week of December will become busier and sort of a transition from what we have seen most of this month to a stormier and somewhat colder pattern.

We will get busy on this forum later this month and much of Jan and Feb after a rather quiet Dec. No changes to winter as the east coast should be hit the hardest in terms of winter weather but we will be on that western edge with many systems and hopefully one or two blow up this side of the mountains.

06z NAM coming in a bit wetter with 0.60-0.70" locally. We look to be reliant on the northern wave for our precipitation. It'd take one heck of a shift to bring us back in the game with the east coast low. Even so, 0.50-0.75" forecast I have looks to be on track.

Trevor wrote: ↑Fri Dec 15, 2023 4:16 am 06z NAM coming in a bit wetter with 0.60-0.70" locally. We look to be reliant on the northern wave for our precipitation. It'd take one heck of a shift to bring us back in the game with the east coast low. Even so, 0.50-0.75" forecast I have looks to be on track.

Hey Trev and will watch the Nam more in this time range. If the Nam keeps getting wetter over the next 24 hours this tells me the system in the Ohio Valley is stronger and may help pull the coastal somewhat closer. Still some tweaks in the forecast. You are a tad higher than me on totals but we are in the same ballpark.

Good morning all and Happy Friday! I like the call of precip by most on here with the best rain chances coming Sat evening thru Sun morning. Longer in the East, a shower duration in the West. Same with rainfall amounts. Lighter NW, heavier SE. For snow lovers, we get a little action with some snow showers possible on Monday into Monday evening on the backside of this system with that third piece of energy dropping into the trough. Best chance NE counties, lowest in the SW.

Then we are cold on Tues with highs in the 30s then we warm up again. The next system of interest comes in around Christmas time. Unfortunately, it looks like a rain maker at this point in time but we'll see. Not all guidance agrees on this storm's evolution since we're around the Day 10 time period.

2 weeks now in the books. +4.3 temps and close to an inch below normal QPF at Cvg. Expect more of the same at least the next 10 days . As Tim has been saying nothing exceptional warm or cold. 500mb pattern still has a long way to go. The flow for the lower 48 and much of southern Canada remains PAC dominated biggest anomalies remain in Canada and upper plains

1.5” for Cincy on the 12z NAM. It’s what I talked about yesterday. The northern low will slow down and enhance as it is absorbed by the main low on the coast.

12Z HRRR doesn't quite go out far enough but you can tell that it is slowing down the northern shortwave also like what the NAM is doing. 9Z SREF has 0.65" for CVG as the mean.

New MEI value is out for ON. It is at 0.8 per: https://psl.noaa.gov/enso/mei/

Nice call Trev with regards to the speed of the northern shortwave. 12Z GFS is slowing things down a tad as well.

The model average appears to be right around an inch. If this wetter trend continues my 0.50-0.75 will move to 0.75-1.00.