Thursday, Feb. 14, 2019 4:30 P.M.
Snow possible tomorrow night!
Happy Valentines Day!
First of all – tonight. A weak cold front will cross the area. It has little upper air support and slim moisture available. Nevertheless, it could squeeze out a few, brief light showers tonight. Only about a 30% chance for a measurable amount. Temperatures tomorrow should stay near 40 during the day.
The northwest U.S. is being pounded by yet another winter storm. A small piece of upper air energy is breaking away from the parent system and will move eastward across the country over the next two days. Both the GFS and NAM portray this system a little stronger than yesterday. They still differ on the storm path and consequences for us.
The GFS is gung ho on snow for us as the surface system slides south of us tomorrow night. GFS snow totals are around 2″ for Louisville area with heavier totals (up to 4″) over SW Indiana and western Kentucky. Snow forecast is even higher along a path from near Evansville to south of St. Louis to Kansas City.
Then, there is the NAM. Like yesterday, it isn’t taking the snow very seriously for the Louisville area. It projects the storm track to be a little farther south. That puts us on the northern edge of the snow threat. Southern KY will see a mix of snow, sleet, freezing rain and rain creating major road problems tomorrow night and early Saturday. It also has the heavy snow from far western KY back into Missouri.
So, which model is correct?
Good question. Can you wait until Sunday morning for the answer? Of course not! We want to know beforehand. So, I’ll give you my thoughts on the situation.
In general, most of the forecasting fraternity will go with the GFS. Over the long haul, it seems to be the better of the two. But, this winter the GFS has had snow lovers salivating over two big snow forecasts. Both times local media and National Weather Service followed the GFS and went into hype mode only to have both forecasts fail. Overall, the GFS has been in a slump but the NWS is going along with its 2″ forecast for tomorrow night.
But, what about the NAM? It’s a good model, too. But the wide differences between the two models for this forecast must mean something. If tomorrow night’s weather solution were “settled science”, the two models would be very close. The fact that they are not close tells us there is something about this atmospheric setup that they can’t quite resolve. In essence, neither model can be ignored.
So, here’s my best shot. I’m leaning toward the NAM ideas having the surface storm taking a more southerly track. That means less snow for the Louisville area. I’m expecting less than one inch for Louisville metro. Snow totals will increase south of the city and could get an inch or two down to the E’town area. South of the parkway they’ll see the wintry mix described above.
West of Louisville snow accumulate along and south of I-64. The farther west in IN/KY, the more snow – as high as 4″ near Evansville. North of Louisville, little or no snow will fall.
Again, I believe the Louisville area will be on the northern edge of the snow system. I expect less than 1″…probably closer to the lower end of the range.
For hundreds of years BCE (B.C.), the Romans celebrated a Spring ritual known as Lupercalia. It was a fertility rite to welcome back the growing season, among other things. It was celebrated around February 14th. About 500 CE (A.D.) the Catholic Church decided that Lupercalia was a little too bawdy for its flock, so it was banned. It was replaced by a new Church holiday they named Valentines Day in honor of an Italian saint who had been decapitated (by the Romans).