After this past weekend's massive snow-storm across the area, with most areas recording in between 5-9" of snow for the total event, we are still expecting an active winter-weather pattern. Unlike last-winter, as most people recall did not feature many significant winter-weather events until early March, this year, the weather-pattern seems loaded with winter-weather events and fresh Arctic air for the area. And it doesn't appear that the end is in sight anytime before Christmas.
There are two major things that bear mentioning right now. First, the Alberta Clipper, which could dump a quick 2-3"+ of snow across much of the area [mainly north and east of U.S. 30]. Secondly, a potentially major winter-storm for the upcoming weekend, which will occur in two-segments.
Tonight's Alberta Clipper
Although this will not likely be a major-event, I do expect that this clipper system will be a bit of a nuisance for the region, especially in exasperating already icy-road conditions, and making for ideal blowing snow Tuesday morning and afternoon. As you can see [below] from radar imagery, the system is not all that impressive. However, this system has unusually high amounts of moisture for a clipper-system, as well as strong omega in an already saturated DGZ [Dendritic Growth Zone; the most efficient layer for snow-crystal formation processes] layer, allowing for a brief burst of moderate-heavy snow, putting down 1-3" of snow across the area.
Not only this, but there are certain other mesoscale processes that could come into play to enhance overall snow-totals tonight, including, but not limited to mesoscale-banding [frontogenesis], higher mid-level lapse rates, and possible slowing of the system itself. All of these factors will go into producing a quick two or three inches of snow for parts of the area [most of the area will likely see about an inch of snow].
However, this is not the only clipper-system that will be moving through in the next 48-hours. By Tuesday morning, another clipper-system will be on its way into the area, and produce a quick burst of moderate snow for the area. This time, its possible that the clipper tracks farther south and thus produces some slightly "heavier" snow totals than originally anticipated. However, at this time, it appears that snow will be around an inch for tomorrow's event. After the clipper passes through, it appears that windy conditions will set-up across the area, leading to significant blowing and drifting snow. This will definitely cause hazardous travel on Tuesday night and Wednesday, and something that needs to be monitored.
Both of these events will put one to as much as four or five inches of new snow on top of an already widespread snow-pack of 4-8". This will continue to allow temperatures to be colder than usual, and will likely temper the coming warm-up this week and weekend [instead of temperatures in the 50's, its likely that temperatures only reach the upper 30's and lower 40's.]. However, how much snow we see before the warm-up comes will also determine how the next storm-system impacts the area.
Major Weekend Storm-System At this time, there is little to be certain of in regards to what will happen with the storm-system that will impact the area by the end of the week. At this point, all we can say is that the area will be impacted by a significant winter-storm, whether it be heavy rain [and thus cause flooding], heavy icing [a major ice-storm is also possible], and/or a very heavy snow-storm [some models are indicating 1-2 feet of snow possible]. At this point, all of these solutions will be on the table, and will be determined by the strength of an Arctic high across the Northern Plains, as well as the depth of the snow-pack across the area after the Thursday-Friday event ends.
Right now, I am entirely uncertain of what is likely to occur. Each model has their own solution at this point, and although there are not significant differences between runs, there are just enough differences that lead to drastically different solutions. For example [see below], the 12z ECMWF dumps over 2 feet of snow across parts of the area through Sunday. The ECMWF pushes the baroclinic boundary south of the area after the Thursday-Friday event, while at the same time develops an intense low-pressure system in the lower Mississippi Valley. At the onset of the next storm-system, the ECMWF predicts a changeover from ice/rain to heavy snow as the Arctic front pushes southward. While I believe this solution is plausible, there isn't enough certainty to say that its the most likely solution. The GFS brings the area a weaker system, but slightly warmer, with the potential for anything from moderate-snow to heavy rain/ice. On the warm-side of the guidance, the 12z CMC/GGEM brings the area a significantly heavy-rain event while bringing a massive snow-storm to the Great Lakes and Southern Canada.
At this point, I will rule out the GFS solution, because it does appear that whatever system does develop, it will be a significant one, and likely stronger than what the GFS was depicting. The NWS is currently keeping the forecast as a chance of snow [or rain/snow] for the area until details can be hammered down. As for my own opinion, I do believe the current weather pattern does support a possible system like the ECMWF has. The pattern is currently similar to the pattern just before the Groundhog Day blizzard, which we know was one of the worst Midwestern blizzards since the Blizzard of 1999.
No comments:
Post a Comment