January 18-19th Accumulating Snow Threat

[Bgoney]

Going to get a little windy later in the day tomorrow 15-25mph maybe higher towards I70 crew. So some blowing of whatever fluffy snow falls

[Trevor]

Going to get a little windy later in the day tomorrow 15-25mph maybe higher towards I70 crew. So some blowing of whatever fluffy snow falls

Yep. Going to look and feel very wintry tomorrow!

[MJSun]

Looks like we were just issued a WWA at 2:46pm.

Hi neighbor!

Howdy! Looks like we are going to get some snow for once!

One can only hope!!

[tron777]

Good evening all! Sorry for the lack of posts. Been busy (not that I wanted to be).

18Z Euro looks great! I will post the QPF for you all from now thru Sat morning.

CVG - 0.22"
HAO - 0.21"
MGY - 0.22"
DAY - 0.21"
CMH - 0.23"
FGX - 0.27"

[mainevilleweather]

I got a flight leaving CVG at 7:50am. Could be a tough drive from Maineville....

Before you head out you may want to check with the airport re your flight.

Still holding at 27 here in G'ville.

For sure!

[mikeyp]

Already looks like the storm is about to phase together

[tron777]

34 here for the high, CVG 33. Currently CVG is 31 / 13 and I am 31 / 15 so dews are slowly coming up as we try and get the column saturated. SPC meso page this evening shows a 1046 MB arctic high in MT that will be delivering our next shot of cold air for the weekend. A weak low of 1016 MB is over the TN / NC border. Moisture in the upper levels at 700 MB is moving into the area. PWATS are up to 0.4" S of the River 0.3" North and 0.5" in Central KY.

The snow on radar over Central KY is trying to move to the NE and expand but we have to overcome some dry air first. The main system and area of snow is still back to our NW over Iowa, MO and getting into ILL. That is where the bulk of our snow comes from. Areas that do really well will be areas that can tap into the central KY snow and add on snow from the area to our NW. Trends in the modeling today has been for our Eastern and SE County zones. I think most folks should be in that 1-3" range but if you can get snow from both areas that I just talked about 4"+ amounts would be possible. It is a nowcast pretty much at this point.

[tron777]

Latest thinking from the boys:

A lull in snow coverage is expected early this evening before
multiple waves of snow move into the region tonight. The first wave
begins to move in from KY and will start to accumulate snow in our
northern KY counties, mainly around midnight. Shortly after this
time, a shortwave trough will begin to propagate through the Midwest
region. This feature will provide ample lift across the region to
usher in widespread snowfall across our CWA. Snowfall rates will
begin to increase after about 4AM. Snow ratios of 16:1 to around
20:1 will lead to rapid accumulations with this snowfall late
tonight. Given the overall timing of this system, favorable SLR`s
and frozen ground temperatures, have decided to expand the Winter
Weather Advisory for the entire CWA given the overall impacts.

&&

.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Efficient snowfall continues through Friday morning as the shortwave
traverses the region. Will continue to observe the best
accumulations through about noon on Monday across the entire
CWA, with snowfall shifting more towards portions of
central/west-central OH and portions of the Scioto Valley.
Persistent northwesterly flow will help lead to longer periods
of snowfall across our central OH counties throughout the
daytime hours and even into Friday night. Accumulations do
become lighter Friday afternoon in that area, with limited
accumulations expected once we get into Friday night as the best
snowfall/forcing shifts eastward.

Given the latest 12z guidance showing higher snowfall potential
around the Tristate area, have trended snow totals slightly higher
compared to previous forecasts. There will likely still be a general
minimum in snowfall totals around the Tristate area as this region
will receive less snowfall being on the western fringe of the
southern snowfall wave, and on the southern extent of the best
snowfall from the northern shortwave trough. Overall, highest
accumulations expected in west-central OH as 3-5" is still possible,
capturing the higher end of snow potential in our CWA. As we
progress southward, 2-4" becomes more favored across the majority of
counties north of the OH River. Along/south of the OH River is where
1-3" of snow is then expected given that less accumulations will
occur form the northern shortwave trough.

Other concern to highlight for this period will be the falling
temperatures into the single digits Friday night. Combined with
breezy winds out of the NW, this will lead to sub-zero wind
chill values across our entire CWA.

[tron777]

WAVE3 out of LOU where BG works, will be having an Alert Day update at 8:15pm this evening. You can watch it here:

[tron777]

21Z RAP:

RAP.png

[tron777]

I expect snow to begin in that 11pm -1am window and the best snows should be in that 3 or 4am to 8 or 9am window tomorrow morning IMO as far as timing goes for the best action.

[dce]

It looks to me like the two waves have already linked together. Precipitation from both areas have merged.

[Trevor]

From a radar and mesoanalysis perspective, things look pretty darn good. Pretty confident in 3-4" isolated 5" along and east of 71.

[tron777]

0Z HRRR is coming in and it is looking decent from what I've seen so far.

[tpweather]

It looks to me like the two waves have already linked together. Precipitation from both areas have merged.

Hey Les and its sort of a partial phase so far but probably a little quicker than models showed. Still believe east of here in southeast Ohio and northeast Kentucky have the best shot of higher totals and some folks there might see 4-6. Still believe 1-3 is the correct call locally but even that amount with the already cold ground and more cold working into the system roads could be bad especially side roads all day and probably even on Saturday. How cold do we get and snow cover will make a difference as -20 was how cold it got in parts of eastern Kentucky but they had snow cover so if we get a few inches below 0 is very likely

As we get warm next week eastern Alaska will be turning really cold and though they are always cold in the winter this will be the first time where temps can get into the -40 - -50 range. Keeping the cold on this side of the earth will hopefully help next month in getting the cold back down in the lower 48.

[tron777]

0Z HRRR is def. suggesting the heaviest snows are along and SE of I-71. 2" to 2.5" has fallen by 7am tomorrow morning in that zone and it's not over yet.

[Trevor]

0Z HRRR is def. suggesting the heaviest snows are along and SE of I-71. 2" to 2.5" has fallen by 7am tomorrow morning in that zone and it's not over yet.

Yep that's what I am expecting and backs up the placement on my map.

[tpweather]

Just another possible bust is the ratio. I have been going with maybe 12-1 but that may be low and if that somehow gets closer to 20-1 then there is the bust. Still too early but will watch this especially on Friday as temps will drop all day.

[tron777]

She starts to wind down after 10am on the 0Z HRRR but I would still expect flurries and light snow shower activity for a bit longer. The steady snows will be done by then though for the Metro. After 12-1pm in the East. A solid 2-3" for most, with isolated 4" possible in the East is a very good call to be quite honest. Ok... could be a rough go of it in the morning for me so I need to get to bed. Please by all means keep the discussion going! If it's bad I'll call in. F-it.

[Trevor]

Just another possible bust is the ratio. I have been going with maybe 12-1 but that may be low and if that somehow gets closer to 20-1 then there is the bust. Still too early but will watch this especially on Friday as temps will drop all day.

Ratios should average 13-17:1 for a majority of our snowfall. Then some 17-20:1 snow showers tomorrow afternoon.

[dce]

00z HRRR

[Trevor]

Snow continues to rapidly develop to our west and southwest. It would be a good idea to get where you need to be now if you haven't already. Road conditions are going to go downhill very quickly over the next few hours.

[dce]

The snow looks to be developing quickly. Should begin to see some flakes very shortly.

[Trevor]

Zoomed in view. Let's start seeing some ground reports!

[Bgoney]

Might take a bit to get saturated cvg was 30 and dp of 11 last hour, while Louisville was 31 and 23