Good morning everyone! Over the last two days we have been talking about nothing other than snow across a large sum of the area. There is good news to offer today as IA cleared the snow activity overnight and the current snows depicted by simulated radar below in central/east-central MO (as of 8:05am CST) will be slowly winding down as it drifts southeastward through the day into this evening.
Here’s a synopsis of what to expect going through the remainder of the day: Locations across IA will continue to dry out while lingering energy in the eastern portions of MO will keep scattered snow showers around through the evening hours, though will slowly lose coverage.
Simulated radar through 12am CST tonight: Scattered snow showers progress slowly southeastward through the morning and afternoon hours, continuing the chance in the St. Louis Metro area through about 6pm CST this evening. During the evening hours, patchy snow showers will be located in southeastern MO before diminishing/exiting into western KY/TN around midnight as the upper-air forcing progresses southeast of the area.
Additional snow accumulation through 12am CST tonight reveals generally up to a dusting of snow (0.25-0.75″) at best from here on out across central/east-central MO, including St. Louis. The snow shower activity will be in a weaker state as it progresses through southeastern MO, likely resulting in little to no accumulation.
The potential exists tonight into Monday morning for the development of patchy freezing fog, mainly in the circled region below. The recent snows along with the calmest wind in the area will promote this patchy freezing fog to develop that could lead to a few slick spots in the locations that observe fog. Patchy fog is possible elsewhere across IA and MO, but is not as likely.
The fresh snowpack will enhance radiational cooling tonight and allow temperatures to fall well into the teens for many areas in southern IA and the northern third of MO (model likely underdone in northern MO). Areas that can achieve clearer skies tonight will fall into the single digits, with an emphasis on this possibility near the Des Moines vicinity. During the day Monday, temperatures aren’t expected to warm much as most will only reach the 20s for highs in those areas.
We’re looking at generally dry weather through most of Monday. However, a weak shortwave trough from the Northern Plains will dive southeastward into IA late in the afternoon and especially the evening hours, increasing the risk for patchy precipitation risks. Based on the atmospheric profile across most of IA during this timeframe, it appears the precipitation type would be in the form of patchy drizzle due to a lack of several variables coming together to form ice crystals or snow. This risk could work into far northern MO Monday night.
As discussed in yesterday’s update, we continue to monitor the risk for a potential significant storm system late work week into early next weekend. Shown below are various ensemble runs from the latest GEFS model which depicts quite a bit of agreement regarding a strong system working through the region during this timespan, putting down a swath of snow for some locations. The details will need to be ironed out as the event nears, but the overall pattern favors increased wintry risks lingering through the end of January.
If you have any questions do not hesitate to reach out! Have a great rest of your weekend!