In Depth: Beyond the 10 Day
ROCHESTER, N.Y. (WHEC) — Exciting times ahead on this update of "Beyond the 10 Day" if you are a fiend for cold and snow as the chances for both are going up over the next two of weeks. Currently across the United States, a big storm set to impact the Northwest US is moving in form the Pacific and this energy will be responsible for a snow chance locally towards the end of this week. Over the Central and Eastern US, the jet stream is taking a dip and then moving northeast through the Eastern US bringing us the wintry weather today. Behind this storm, our first legit injection of cold air is expected with wind chills near 0 and temperatures in the 20s for afternoon highs on Monday. This cold shot of air looks to be a taste of the cold that may be on the way towards the end of this week and early next week. Further out across North America, our pattern is already beginning to change. Ridging over Alaska is stretching north and westward over the Bering Strait and our Greenland block continues to break down. Both of these pieces will impact the next two weeks across the Eastern US.
Locally over the next few days, not much change is expected as temperatures will remain near average before the cold air moves in. An Alberta Clipper will swing to our north on Wednesday and bring us a few rain and snow showers, but it’s what’s behind it that we are watching. After this clipper swings through, we will see a period of lake effect setup across the Great Lakes as another shot of cold air swings by locally. Lake Ontario water temperatures remain in the low 40s and with a temperature gradient greater than 10C from the surface to the 850mb layer, there is a good chance lake effect sets up. Right now, winds will likely be out of the southwest which means a better chance for lake effect for Buffalo and Watertown, but we could see a day filled with snow showers and light accumulations with a band from Lake Erie. Something to monitor as we move forward. After that, another chance for wintry weather enters the picture for Friday. Cold air will be in place locally and an area of low pressure will try to form near the Tennessee river Valley and move northeast along the East Coast. Track of this system will be key as if it tracks too far east than we will miss out on the snow. If it travels along the coast or inland, we will have a decent shot of snow locally. Even if this storm misses to our east, we will still have a good shot of lake effect continuing from Thursday. Also towards the end of next week, the cold air will continue to filter in locally as highs drop into the 20s once again for the first part of next weekend.
Another round of unsettled weather and a chance for snow likely rolls in for Sunday. This situation is a bit different from Friday’s snow chance, but similar to the one we are dealing with right now. As of now, it looks like we will be walking the fine line again as we will either be on the wintry side or milder side. It will come down to which area of low pressure is in control. If the piece to the north is in control, than we can expect a milder storm before another shot of cold air. If the southern piece takes control and becomes its own entity, than we will have a good shot of being on the colder side of things with snow. Models are split on the decision right now, but if the southern piece takes over I believe the cold air will be more available than what we are dealing with today, and we see less mixing and a better chance for all snow. If the southern piece does take over, track will be important for us as it will determine whether we see snow or not.
After those two synoptic storm chances this week, things turn quiet synoptically for snow. This is because the jet stream will likely dip well south and run out to sea. I like to call this "suppression depression" as the jet look keeps the storm chances over the southeast and suppresses anything along the East Coast. However, this setup will favor an increase of Alberta Clippers and lake effect. The winds next week in the upper levels of the atmosphere through the Great Lakes will be coming out of the northwest, and with the cold air in place the chance for lake effect locally and snow from clippers will increase. For what it is worth, models the chance for our first decent lake effect event in what feels like forever. Obviously being a week away things will change and this will affect the delicate process of setting up lake snow. Overall, the next two weeks will increase our chances for snow locally whether it be synoptic or lake effect.
Temperatures: Seasonable early before turning below average lake this week and through the majority of next week.
Precipitation: Near normal
January 6th: Lake effect behind Alberta Clipper, Wind out of southwest, watching out for effects from Lake Erie band at this point.
January 7th: Potential storm along the East Coast. How close to the coast or inland does it get? If it does miss, continuation of lake effect.
January 9th-January 11th: Low pressure on Sunday followed by lake effect behind? Track will determine snow and if lake effect sets up behind system.
January 11th-January 16th: Too early for exact timing but northwesterly winds will favor Alberta Clippers and lake effect with the cold air in place and the northwesterly flow.