Absolute Vorticity

They had some dandy snow squalls in the NE yesterday

Bgoney wrote: ↑Sun Feb 20, 2022 7:30 am Return to our 3 days of warmth starting today. Tues rain still a go of course , 1-2" qpf , with the 1" closer to I70 and the 2" along the river , keeping rivers and streams on the high side, but i don't think this will be as widespread 2+" amounts that we just had, Those amounts should stay to our south . Thursday's mess still a go also with 850 temps up and down throughout the region with EU of course much warmer for 850s. Coming in 2 waves scenario,

Good Morning Bgoney, first part of the week much easier and I agree closer to 1 inch is more likely than 2 inches locally. The end of the week system or systems as we could have 2 and maybe 3 waves. The timing of each one is critical and like you mentioned the 850 temps go up and down from later Wednesday until later Friday. I talked about last week how its nice to get a second system come in rather quickly after the first system so we don't warm to quickly and that can be true but moving in to fast behind the first system only lets the cold go so far south. I am not sure models will get a true hold of the second system until Wednesday and by the it will be on our door step. Do we get snow on the ground and if so how cold can we get either Saturday or Sunday morning and will the winds die down and the sky clear. This is a very cold air mass and models will be on the high side in terms of temps next weekend so would not be surprised one or both days highs in the 20's.

GReat post Tim, ATM , there is pretty good agreement on the first wave that has very light amounts of QPF , early thursday morning, That wave should be snow or freezing rain where precip is falling , so the morning drive could be dicey. Then we get the next batch noon or after with of course much more QPF involved and thats when the models differ with 850s

Looking beyond this week and the following week looks to stay rather busy. The mjo is heading back towards phase 2 per the Aussies and that should slow down and then start heading toward phase 4. How long it takes can also determine when we start getting into spring on a regular basis. I still believe the middle of March we see a nice turnaround and still looking at a rather mild spring this season.

12z gfs keeps its theme for Thursday of mostly FRZR along and south of 71 with snow/sleet mix to the north .

Bgoney wrote: ↑Sun Feb 20, 2022 11:14 am 12z gfs keeps its theme for Thursday of mostly FRZR along and south of 71 with snow/sleet mix to the north .

I agree its rather similar to the overnight run and maybe a tad northwest but not much. Only difference I see is on Friday it does try to strengthen the low pressure a little more as it heads northeast through eastern Ky or W.Virgina

No changes for Tuesday rains from post earlier this morning

The Cmc is similar to the overnight run and similar with the late Wednesday/early Thursday 1st wave but it is warmer than the gfs with the second wave but does show the stronger system so that is why we end up with more liquid later Thursday

Really don't want another ice event. Please trend south.

young pup wrote: ↑Sun Feb 20, 2022 11:48 am Really don't want another ice event. Please trend south.

Over the last 24 hrs the GFS has definitely trended NW with the 850 warmth especially into Daytonland

Bgoney wrote: ↑Sun Feb 20, 2022 12:07 pm

young pup wrote: ↑Sun Feb 20, 2022 11:48 am Really don't want another ice event. Please trend south.

Over the last 24 hrs the GFS has definitely trended NW with the 850 warmth especially into Daytonland

Makes sense if the second wave is somewhat stronger as you would expect those temps to be somewhat warmer. So you may get more rain with the second wave but the backside snows may be somewhat higher because the system is stronger but again that is usually not a winner for us in terms of snow. I hope the first wave is mainly snow and would hate to see several hours of frz/rain. Heading into late February though temps in the 10a-4p time period usually rise a little more and unless the precip is really falling hard then liquid has a better shot than frozen and even if it is frozen the solar radiation will help with roads.

tpweather wrote: ↑Sun Feb 20, 2022 9:12 am Looking beyond this week and the following week looks to stay rather busy. The mjo is heading back towards phase 2 per the Aussies and that should slow down and then start heading toward phase 4. How long it takes can also determine when we start getting into spring on a regular basis. I still believe the middle of March we see a nice turnaround and still looking at a rather mild spring this season.

Definitely looking forward to it, bro!

And for the crazy MLB lockout to get resolved soon.

12z EU so far staying with the theme that first wave early thursday is frozen light precip.

Bgoney wrote: ↑Sun Feb 20, 2022 1:19 pm 12z EU so far staying with the theme that first wave early thursday is frozen light precip.

Exactly and going somewhat stronger with the second wave as the other 2 models have shown. This much agreement 4 days away scares me lol.

MVWxObserver wrote: ↑Sun Feb 20, 2022 1:01 pm

tpweather wrote: ↑Sun Feb 20, 2022 9:12 am Looking beyond this week and the following week looks to stay rather busy. The mjo is heading back towards phase 2 per the Aussies and that should slow down and then start heading toward phase 4. How long it takes can also determine when we start getting into spring on a regular basis. I still believe the middle of March we see a nice turnaround and still looking at a rather mild spring this season.

Definitely looking forward to it, bro!

And for the crazy MLB lockout to get resolved soon.

I agree Eric, can make it until the NCAA basketball games are over with but then I need my baseball.

EU says any minor ice from the first wave will be gone during the second wave , for cvgland, above freezing surface temps with the low passing over Lex or just north

Euro adds another wave over the weekend which has been shown from time to time on the models

Bgoney wrote: ↑Sun Feb 20, 2022 12:07 pm

young pup wrote: ↑Sun Feb 20, 2022 11:48 am Really don't want another ice event. Please trend south.

Over the last 24 hrs the GFS has definitely trended NW with the 850 warmth especially into Daytonland

I really don't like that.

No significant changes from overnight mods . Tues still going with 1-2" qpf, north to south. Early thurs morning , pre-dawn, still looks llike light frozen precip along and north of river, with GFS hinting at maybe an inch of snow near I70, then a short break late morning before more moisture works in . GFS continues to move towards EU with warmer 850s, while EU ever so slightly colder surface temps , so for now, along and north of 71 a sleet /FRZ mix and south of 71 FRZR to rain for second wave.

Here is the latest GFS accretion map , (I don't understand why they even have those other freezing rain maps). About a .10- .25" of accumulation. Not a crippler but enough to cause minor issues across the heart of cvgland and surrounding areas

Good morning everyone! Back from ice fishing and it looks like we are dealing with another mess! ILN has a flood watch issued again. It looks like 1-2" of heavy rain coming tonight thru Tues night. Then we get cooler and the kitchen sink is back. Lovely! I've about had enough with ice and sleet. All snow or rain thank you but anyway that doesn't look to be the case. Even the Euro has cooled off from when I left for Michigan. Surface temps for CVG are marginal so it'll be close for big impacts down here. N of the river, a different story of course. Looks like another kitchen sink storm in the works.

Welcome back Les. Hope you had a great trip. This is going to be a busy week.

Thanks Bud! Yeah it will be. With the Thurs / Fri system, this is looking good for the I-70 Crew for mainly wintry weather. I do not like the icing thread for your hood. For down here, it is borderline. If we do not drop to 30 or below, CVG may get away with minor impacts. Ground is warm again and unthawed finally... at least down here... so you are going to need colder air for nice ice accretion to occur. Away from downtown to the north, should be ideal. Any shift to the south in the low track will put more of NKY into the game but for now... the river looks to be the cut off between minor and major impacts from wintry weather.

Down here with everything thawed and more rain coming Tues ahead of the wintry mess, swollen rivers and creeks are also a huge concern.

Folks... Please use the new storm thread to cover the wintry threat coming later this week for Wed night thru Fri. Rain likely for everybody tonight after midnight thru Tues night. Flood watch is out. We can cover that here. The new thread is for the potential wintry mess coming for the forum area with the second low pressure wave riding along the stalled out frontal boundary.

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PV update


The strat. vortex is currently stronger than ERA interim average
and is forecasted to remain stronger than average (according to GEFS-mean)
31 of 31 members have stronger vortex than average at the
last forecast step (2022-03-08 00:00:00)

The zonal mean zonal wind at 10 hPa 60N is today (GFS analysis): 41.8 m/s
Weakest zonal wind at 10 hPa 60N in ERA interim record for todays date is: -22.9 m/s 2018
Strongest zonal wind at 10 hPa 60N in ERA interim record for todays date is: 53.7 m/s 2020