Absolute Vorticity

This is comical now. ILN has issued a WWA for 3-5" for Eric and Dave's hoods.... 2-4" for CMH Metro... and 1-3" for our Eastern counties and SE Crew zones. I get all that. I am fine with it. What do we get in No Man's Land? A special weather statement!

...ACCUMULATING SNOW THIS EVENING THROUGH FRIDAY EVENING...

Accumulating snow will be possible primarily this evening through
Friday evening. 1 to 2 inches of snow will be possible. With cold
air in place, even small snowfall amounts will lead to the
potential for slick road conditions. Use extra caution if
traveling during that time

I totally understand though. It's because of the dry slot obviously.

0.08" from the 6Z NAM here in No Man's Land. So it looks like we have the NAM and HRRR against the other modeling world. Hi Res / Meso scale modeling gives us the dry slot where the globals do not. It is tough to go against the short range models IMO this close to game time. I will be keeping my ongoing forecast as is that I made yesterday.

Current SPC meso page shows the lead low at 1006 MB over OK and the main low at 1002 MB over Eastern WY. So far, the storm evolution has been what I have been saying. The F-gen / WAA snows are occurring well to our north over S Mich and back to the SW over ILL and MO.

Feel pretty good with forecast ranges. NAMs why I went with a dusting on the low end for cvgland . Too late for changes anyways , ride it out It’s in Ma natures hands to deliver . Dusting -2” counties bordering river and 1-3” north of that to I70

Bgoney wrote: ↑Thu Jan 18, 2024 5:18 am Feel pretty good with forecast ranges. NAMs why I went with a dusting on the low end for cvgland . Too late for changes anyways , ride it out It’s in Ma natures hands to deliver . Dusting -2” counties bordering river and 1-3” north of that to I70

Exactly! I couldn't agree more.

6Z GFS has 0.23" for CVG so it's still not backing down. Model showdown in progress....

I think the high res will cave this time. Forecast update coming mid morning which includes increased amounts for the area.

I will also be debuting a new style to snowfall forecast versus ranges so stay tuned for that.

Trevor wrote: ↑Thu Jan 18, 2024 6:09 am I think the high res will cave this time. Forecast update coming mid morning which includes increased amounts for the area.

Good luck my friend! Hope you are right on this one.

SPC Meso page this morning shows a 1006 MB low over the Red River (TX / OK border) and the main low over SE WY at 1004 MB. Can we get any phasing between these two lows to allow for higher QPF totals and less in the way of a dry slot? WAA / F-gen forcing snow continues in an arc from SE MO, ILL, NW IN on up into Southern Mich. A nice area of snow from the other low in WY is falling over Eastern MT and the Northern half of SD as well as portions of CO. Can we get these two areas of snow to merge tonight into tomorrow as part of the phasing process? Lots of moving parts to this one. Bust potential is there for sure. If we see the phasing occur too late or not at all, then the dry slot will impact us and those of us going lower will be correct. If we can get some phasing between the two systems then folks going with the higher amounts will be correct. It'll be interesting to watch the latest data today as well as real time observations (now casting) to see how things evolve.

6Z RGEM is really close with the dry slot but the Cincy Metro avoids it on this run. It is very close to our top tier of NKY counties (Boone, Kenton, and Campbell).

3Z SREF Mean snowfall

CVG - 1.47"
HAO -1.67"
ILN - 2.19"
MGY - 1.89"
DAY - 1.97"
CMH - 2.44"
ROD - 2.67" (Sidney, OH)

Latest thinking from the boys:


.NEAR TERM /UNTIL 6 PM THIS EVENING/...

Mid and high clouds continue to move across the region this
morning in advance of a low pressure system. For the daytime
hours today there are varying solutions as to how much snow will
occur. There are some indications that there will be some light
accumulating snow near or near and northwest of the Interstate
71 corridor mid day to early afternoon. Did not go overly high
on precipitation chances however given low level dry air in
place. Cannot rule out some light snow, however confidence in
snow accumulating during the daytime hours in any particular
location was low due to the dry low level air.

Temperatures will be a little warmer than temperatures this past
week with highs expected to be in the upper 20s to middle 30s.


&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/...

Key message for the short term period is that accumulating snow
will bring the potential for slick road conditions to the
region.

Issued or continued a winter weather advisory for areas with
highest confidence on advisory level snow. Issued a special
weather statement for the remaining areas. Cannot rule out that
an advisory will be needed for the remainder of the area with
subtle shifts in storm track, greater snow ratios, or based off
of impact. Tricky snowfall forecast for the short term with
tight gradients in snowfall expected.

While one area of low pressure will move south of the region, a
secondary surface low is expected to move near the Interstate 71
corridor this evening into tonight. The exact position of that
low will have implications for snowfall values.

There will be moisture brought up into southeastern portions of
the region this evening and also a corridor of snow northwest
of the low across northern portions of the region. In-between
the two areas expect lower snowfall values.

The surface low will start to push off to the east late tonight
into Friday morning. An upper level disturbance will start to
move through and there will be favorable winds off of the lake.
This disturbance along with supportive wind direction will allow
for snow shower activity to continue for the remainder of the
short term across the region with some higher enhanced snowfall
values across northern portions of the forecast area.

Totals across far northern portions of the region will have the
potential for 3 to 5 inches with locally higher amounts. Have a
corridor of 2 to 4 inches in an advisory as well and then
another area of 1 to 3 inches. Kept locations with 1 to 2 and
locally higher amounts out of the advisory at this time due to
lower confidence in snowfall values in these areas closer to the
low, however as mentioned previously cannot rule out that the
winter weather advisory might need to be extended with time if
nothing else based on impact alone.

Temperatures will fall Friday afternoon as cooler air works into
the region. Wind chill values by the of the daytime hours on
Friday will be down into the single digits. Wind gusts on Friday
will be in the 20 to 30 mph range.

By any measure, I qualify as a snow "weanie." At this point, however, I am not sure if I am rooting for us to get a decent snowfall to satisfy me or the other snow "weanies" I follow on this forum. Throw out the science. Simple fact is we are overdue!

Nice donut hole!
At least stand up the advisory. Just shortsightedness all the way around. When people ignore what is said, we will all understand why.

wxpatriot1 wrote: ↑Thu Jan 18, 2024 6:51 am By any measure, I qualify as a snow "weanie." At this point, however, I am not sure if I am rooting for us to get a decent snowfall to satisfy me or the other snow "weanies" I follow on this forum. Throw out the science. Simple fact is we are overdue!

We've been overdue that is for sure! I wish Mother Nature would get the memo!

fyrfyter wrote: ↑Thu Jan 18, 2024 6:53 am Nice donut hole!

IMG_7671.jpeg

At least stand up the advisory. Just shortsightedness all the way around. When people ignore what is said, we will all understand why.

ILN's AFD that I posted explains why we have the donut hole. I can't blame them to be totally honest. We know the dry slot is very possible.

tron777 wrote: ↑Thu Jan 18, 2024 6:13 am

Trevor wrote: ↑Thu Jan 18, 2024 6:09 am I think the high res will cave this time. Forecast update coming mid morning which includes increased amounts for the area.

Good luck my friend! Hope you are right on this one.

HRRR may be close to being the solution , I don’t know . The good news is the long range of the Hrrr has been pretty bad for winter forecasts. I don’t trust it until 24 hrs or less

Bgoney wrote: ↑Thu Jan 18, 2024 7:26 am

tron777 wrote: ↑Thu Jan 18, 2024 6:13 am

Trevor wrote: ↑Thu Jan 18, 2024 6:09 am I think the high res will cave this time. Forecast update coming mid morning which includes increased amounts for the area.

Good luck my friend! Hope you are right on this one.

HRRR may be close to being the solution , I don’t know . The good news is the long range of the Hrrr has been pretty bad for winter forecasts. I don’t trust it until 24 hrs or less

What bothers me is that the HRRR is not alone. It has the NAM, FV3, and ARW on its side. These are all hi-res / short term models.

6Z Euro QPF

CVG - 0.19"
HAO - 0.22"
MGY - 0.23"
DAY - 0.25"
CMH - 0.28"
FGX - 0.25"

tron777 wrote: ↑Thu Jan 18, 2024 8:10 am 6Z Euro QPF

CVG - 0.19"
HAO - 0.22"
MGY - 0.23"
DAY - 0.25"
CMH - 0.28"
FGX - 0.25"

Euro has been consistently in the range .15-.25” for the region as a whole for quite a while

It would be nice to see the Euro do well that is for sure. 12Z HRRR was improved over 6Z. I think it has sped up the main wave just a bit so that the dry slot narrowly avoids us. That is going to be key for sure with regards to QPF, snowfall duration and avoiding the dry slot.

tron777 wrote: ↑Thu Jan 18, 2024 6:40 am 3Z SREF Mean snowfall

CVG - 1.47"
HAO -1.67"
ILN - 2.19"
MGY - 1.89"
DAY - 1.97"
CMH - 2.44"
ROD - 2.67" (Sidney, OH)

For comparison... here's the 9Z SREF

CVG - 1.41"
HAO - 1.77"
ILN - 2.24"
MGY - 2.23"
DAY - 2.65"
CMH - 2.76"
ROD - 3.44"

tron777 wrote: ↑Thu Jan 18, 2024 8:35 am

tron777 wrote: ↑Thu Jan 18, 2024 6:40 am 3Z SREF Mean snowfall

CVG - 1.47"
HAO -1.67"
ILN - 2.19"
MGY - 1.89"
DAY - 1.97"
CMH - 2.44"
ROD - 2.67" (Sidney, OH)

For comparison... here's the 9Z SREF

CVG - 1.41"
HAO - 1.77"
ILN - 2.24"
MGY - 2.23"
DAY - 2.65"
CMH - 2.76"
ROD - 3.44"

Think everyone would take that and run with it

For sure Bgoney! 12Z NAM is running so let's see what it shows. I hope it trends more favorably like the HRRR did.