Monthly Archives: January 2023

It’s complicated…

5 P.M. Monday, Jan. 30, 2023

General situation shows a large cold air mass over the midwest slowly dropping southward. Temperatures today have been slowly falling and will continue tonight as temperatures drop into the upper 20’s by morning. Meanwhile, a small upper level disturbance in the jet stream flow will move rapidly ENE over the area tonight. It’s not much of a system, but it does have enough moisture to bring us some icy weather tonight.

That’s where the forecast trouble starts. The lower atmosphere (up to 5,000 feet) is definitely cold enough to support an inch or two of snow overnight along the Ohio River. But, it’s not that simple.

There’s a pocket of slightly above freezing air roughly between 5,000 and 10,000 feet above us. That will be slowly cooling overnight but should still stay slightly above 32 degrees. That’s the fly in the ointment.

The primary consequence will be that some of the snow falling through this warm layer will melt, then refreeze into sleet before hitting the ground. That sets up a very subtle balancing act between snow and sleet for our overnight entertainment.

In general, the whole atmospheric column will be slowly cooling, so snow becomes the most likely result as time goes on. The onset is trickier. Everything depends upon just how thick that warmer air is and how much cooling it will get from evaporation of precipitation aloft.

The models are consistant on two things. First, the amount of moisture falling will be small. Probably between .1″ and .2″ of water. That would be a 1″-2″ snowfall but only about a quarter-inch of sleet. Second, the location of the maximum precipitation will be about roughly 30 miles north and south of the Ohio River.

After putting all those variables into a big pot and letting them simmer, here’s what I think will happen tonight. Precipitation should begin around 8 P.M. in Louisville. At first, it’ll be mostly sleet with a little snow mixed in. As the night goes on, the mix will gradually change to mostly snow with a little sleet mixed in. Any significant snow/sleet will end by 3-4 A.M. The Louisville area should end up with a snow/sleet total of up to one inch.

North of Louisville snow totals could get up to 1″-2″. South of Louisville will see a snow/sleet accumulation up to one-half inch.

By morning rush hour, treated roads should be in fairly good shape with icy spots. Meanwhile, non-treated roads should be mostly snow/ice covered.

Snow tonight

Mon. Jan.30, 2023 12:30 P.M.

Forecast models are all over the place with tonight’s forecast. However. it now appears that we’ll see an accumulation of snow tonight. At this point it looks like an accumulation of about 1″ – 2″ around the Louisville metro area with slightly higher totals over southern Indiana.

If that pans out, school kids could see a free day tomorrow. However, as pointed out above, forecast models are unusually scattered for an event so near in time.

More later…there’s a lot to digest.

Snowball fight

Today’s models can’t seem to agree on snow tonight, but rain is a sure bet.

First, a note on Sunday’s snowfall. Sunday’s weather events gave yet another reason why weather is so fascinating. Both the event itself and the (lack of) forecasting it. Rain was the models’ choice while also giving hints that there could be some snow at the start. But nothing like the 1″+ we had around the county. And that’s about the only place snow fell.

As the rain moved in, a sudden intensification of the precipation brought colder temperatures AND snow into Jefferson County and almost nowhere else.

Weather can be so much fun!


Meanwhile, tonight’s system will be much stronger and almost all signs point to rain. This morning, the GFS was the only model predicting snow at the start with a quick change to rain. Now, other models are drawing closer to the snow start followed by rain. Temperatures with this system are about 3-5 degrees warmer than Sunday’s, so if any snow falls, it’ll melt quickly.

Snow and/or rain should begin around Midnight or shortly after. By 2-3A.M. any chance for snow will be gone. After that, periods of rain will continue during the morning then fade away by late afternoon. Winds will pick up during the afternoon with gusts probably topping 35 mph.

Snow flurries will be likely tomorrow night and Thursday.


The northernmost point of Brazil is closer to Canada than it is to the southernmost point of Brazil.


Now looks like an hour or two of snow/sleet will be mixed in with the onset of rain around daybreak. Any minor accumulations on grassy areas will fade away during the morning.

Rainy Sunday

Saturday, Jan.21, 2023 6 P.M.

I’ve been watching the models’ handling of the next two storms headed our way. Both have been indicating a cold rain for tomorrow and for Tuesday night/Wednesday. The second on will be much stronger (for us).

Yesterday, words like snow, sleet and freezing rain started entering the forecast. A deeper dive into the weather data made me believe those words shouldn’t be there. The atmospheric setup just isn’t cold enough.

A storm developing over Texas tonight will advance ENE over the Gulf Coastal states tonight and tomorrow before turning up the Atlantic Coast tomorrow night. With the storm staying so far to our south, we’ll be on the northern fringes, so rain totals will be on the light side.

Models agree that the rain/snow line will be at least 30 miles north of the Ohio River. So, don’t be surprised if we see a little wet snow mix in from time to time. Basically, though, we’re expecting just a cold, rainy morning. Then rain will slide eastward by early afternoon.

Models also point to another (mostly) rain event by midweek, so snow lovers are probably in for another disappointment with that system.

Meanwhile, global models are pointing toward below normal temperatures here for the next week or two. So, we’ll see additional snow chances ahead.