BuffaloWeather

Lake Effect .LONG TERM /FRIDAY NIGHT THROUGH MONDAY/... Confidence continues to increase that the coastal system to end the week will be followed by the potential for an impactful lake effect snow event this weekend, mainly E and NE of the Lakes. Coastal low will continue to strengthen as it moves slowly NE across eastern New England Friday night, before moving NNE through far eastern Maine on Saturday. Colder air will get drawn into the region Friday night in the wake of the occluded FROPA with any lingering mixed precipitation going over to all snow across western and northcentral NY. Airmass aloft then grows cold enough aloft to support a lake response starting late Friday night with lake effect snow expected to begin off the E/NE end of Lake Erie. Meanwhile widespread synoptic snows associated with the coastal low continue east of Lake Ontario. Primary area of synoptic precip east of Lake Ontario pulls northeast of the area Saturday but mid and upper level cyclonic flow and deeper synoptic moisture remain in place through this weekend while it just grows colder aloft to support lake effect snow. All of this will only further support the development of potentially heavy lake effect snow downwind of the Lakes. At this point, the overall large scale synoptic pattern and local climatological analogs are not quite ideal for a *sustained* SW flow lake effect event. It seems to start that way later Saturday into Saturday night but by later in the weekend flow veers enough to put emphasis to south of Buffalo into the Southern Tier and eventually more on the Tug Hill instead of Watertown/Fort Drum. CIPS analogs and local guidance seem to favor those areas favored by more 260 flow as seeing the greatest chances for longer duration significant lake effect this weekend. That seems reasonable based on especially sfc-H85 trough that elongates over time instead of staying persistent vcnty of northern Ontario and James Bay. As a bonus even the Canadian-NH which typically performs superior with these type of lake effect events is showing that. Supplementing factors will be in play as well including upstream lake connections and potential of several shortwaves pinwheeling through the main upper trough that will likely both enhance lake snows from time to time, but also disrupt wind flow at times causing the bands to temporarily shift. This could limit accumulations in any one location at least providing some breaks in the activity. Eventually the upper level low slowly shifts east to just north of the area Sunday before shifting east across New England Sunday night. This will veer boundary layer flow some with lake snows shifting more due east or even southeast of the Lakes Sunday night. High pressure, drier air and increased shear will start to build in for the start of the new work week which should start to weaken lake snows on Monday. All of this said, timing and location of the lake effect snows will continue to be refined as we get closer to the actual start of the event, especially as higher res model data starts to be included. As folks well versed with lake effect know, it just takes a wind direction change of 10 degrees to make all the difference as to where heaviest band of lake snow occurs. Main point now is to stay up to date with the latest forecasts and statements.

Looks like snowstorm followed by LES for upstate this week Snowstorm: .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... ...Snow and ice possible Thursday with several inches of snow Thursday night into Friday eastern areas... High amplitude pattern with omega block to start will bring a complex winter weather scenario to our region starting late Wednesday night and lasting through Friday. Then into the weekend, lake effect takes focus and that is covered in the long term potion of the discussion. General model agreement in large picture. Broad large upper low over the central Plains with occluded sfc low slowly moves across the Great Lakes through Friday. Occluded front ahead of the low and very moist isentropic ascent along that front will bring a slug of widespread precipitation into far southwest NYS late Wednesday night, spreading across rest of the forecast area on Thursday from west to east. Due to strong high pressure ridge centered over Quebec, it likely takes until late afternoon until any precipitation reaches the eastern Lake Ontario region. That high will be a big player in ptype, which flat out is quite the mess, especially Thursday morning into early Thursday afternoon. Warm air aloft along the occluded front with some guidance showing warm layer at H85-H8 as warm as +5c will be flowing atop temps at the sfc that will be sub-freezing (25-30 on average) thanks to easterly flow out of the high. At first glance, a freezing rain scenario if one had to pick just one ptype. No can do though as some guidance is colder and would favor more sleet and even snow for a while before changeover. Thus the forecast has pretty much all winter types in it right now. Risk for freezing rain and icing of up to two-tenths of an inch is highest over inland portions of western NY down across the Southern Tier while lower elevations that could see wintry mix earlier on Thursday should switch to rain with downslope se flow warming near sfc temps enough. Once you get east of the Genesee valley and maybe even slightly west of there, mainly just snow for ptype as this warm layer stays at bay to the west. Now, come mid to late afternoon, the ptype evolution changes as in a Miller type B fashion the main focus for low-level cyclogenesis will shift to along the Carolinas. By that time, warm nose aloft pretty much disappears so that any ptype issues late Thursday afternoon onward will be function of near sfc temps as aloft, it will be mainly a snow scenario. By sunset Thursday evening, best chance for several inches of snow would be centered on the Genesee valley while best chance for ice would be in areas highlighted earlier. Elsewhere, a messy mix will lead to minor snow and ice amounts. These are just estimations right now and caution is advised that with such a dynamic system, ptype and amounts of snow and ice could change from this forecast. A couple of alternate scenarios would be if the warm layer is quicker to diminish or not as strong in the first place that would lead to more snow on the front side of this system. Or, if the warm layer hangs on longer, then that would result in more ice at least inland from the lakes. Will be something to watch as we get closer. Thursday night the main emphasis will shift to the Finger Lakes and eastern Lake Ontario region. Snow will be the main ptype by then and there could be several inches of heavy wet snow into Friday. Lower elevations will still see a mix of rain/snow which would limit snow accums. CIPS analogs and probability guidance hits the terrain in a swath from western Finger Lakes to the Adirondacks and on to the south and east for the heaviest snow potential. Meanwhile back west over western NY expect a chance of rain/snow with minimal snow accumulations as main focus will be off to the east. Expect highs in the lower to middle 30s higher terrain and upper 30s lower elevations.

Although synoptic precip east of Lake Ontario pulls northeast of the area Saturday, mid and upper level cyclonic flow and deeper synoptic moisture will remain in place through this weekend, which will only further support the development of potentially heavy lake effect snow downwind of the Lakes. ***At this time*** the overall flow looks to average 250-260 degrees Saturday through Sunday, directing lake effect plumes E/ENE of the Lakes through much of the weekend. That said, the mid and upper level low is not in the ideal climatological position with it being centered over the upper Great Lakes on Saturday. Would like to see it displaced further north, however still looks favorable synoptically. Upstream lake connections will also play important roles. In addition, the center of the upper low will drift east through the weekend with several shortwaves pinwheeling through the main upper trough that will likely both enhance lake snows from time to time, but also disrupt wind flow at times causing the bands to temporarily shift. This could limit accumulations in any one location at least providing some breaks in the activity. Upper level low slowly shifts east to just north of the area Sunday before shifting east across New England Sunday night. This will veer boundary layer flow some with lake snows shifting more due east of Lakes Sunday night. High pressure, drier air and increased shear will start to build in for the start of the new work week which should start to weaken lake snows on Monday. All of this said, timing and location of the LE snows will continue to be refined as we get closer to the actual start of the event, especially as higher res model data starts to be included.

A storm system moving out of the Plains has the potential to bring a variety of wintry precipitation Thursday into Friday. Most of the precipitation should fall as snow, but some rain, sleet or freezing rain may also mix it. Several inches of heavy wet snow is possible along with minor ice accumulations. There is the potential for significant lake effect snow this weekend. There is still considerable uncertainty in the exact placement of the lake effect bands and amounts, but it is possible there will be periods of heavy snow across southern Erie and Wyoming counties, as well as the western Southern Tier.

Check your pms stash.

Heading into the weekend, the air mass aloft will become cold enough (model 850mb temperatures range from -10 to -14) to support a lake response. Model guidance packages from 11/00Z, 11/12Z, and 12/00Z continue to support unidirectional vertical wind profile in the lower levels along with the cold temperatures aloft to support lake snows east/northeast of both lakes. Despite the model continuity, this event remains in the farthest reaches of the forecast and therefore the mesoscale features are yet to be well represented this far out. But as of right now, there is high potential for lake effect snow east and northeast of both lakes Erie and Ontario Saturday through Sunday.

Lock it in

Bills snow game next weekend?

In a general sense, a -AO/-NAO pattern increases the likelihood of impactful winter weather in the northeast US, but in this case it is also coupled with a -PNA pattern, which favors cold to be focused more in the Northwest US and northern Plains with seasonable warmth favored on average in the eastern US. Model guidance continues to show considerable uncertainty starting next weekend with significant run to run swings in the handling of synoptic scale details, which is to be expected in a large scale pattern such as this. This will likely continue in the coming days as model guidance attempts to distill this low predictability pattern. Any one model run should be taken with a grain of salt in this pattern.

It finally melted

Had 2 free PTO days from work. In 2014 I had a full week off paid. I love these events lol.

This event was quite widespread. The low QPF LES events usually happen early on in the year when the lakes are warm Nov/December primarily. The BUF NWS has a nice page that keeps track of LES events. I probably average a 2 footer + per year. I don't live in the snowbelt, just a southern suburb. South of here in the snowbelts average 200"+ and off the tug 300"+. I'd say almost every year we get a 3-4'+ event off Erie and off Ontario the potential is greater. https://www.weather.gov/buf/lesEventArchive

my socials went nuts, over 20 million impressions between youtube and twitter, I was debating on what event I liked more between 2014 and 2022. 2014 had whiteouts like I've never seen with the higher winds and 2022 had nonstop thundersnow. They are my 1a/1b at top above every other event.

Highest I saw was 5.5” QPF

Still a few inches on the ground here. Stuff had sticking power with 5” SWE in my core sample. We had 40s and 50s for almost 2 weeks straight. Had snow on ground from Nov 16-today. I’m a snowfall rates guy so dont really care about snow depth unless it’s extreme 3’+. It snowed a few hours after this, but this was close to the max depth.

Nov Temps: BUF: +2.3 ROC: +1.9 WAT: +3.0 SYR: +4.7 BING: +3.2

LES chase last night

Another close call up in the high peaks. Becoming a far too common occurrence these days. https://dailygazette.com/2022/11/30/missing-schenectady-teen-found-freezing-in-adirondacks-dec-says/?fbclid=IwAR0XLpuEnFHmQNIhy6s4mZYGLjzScSB5sjIbC8Ibe1d6ht6-ELfpE7boZOM

Picked up an inch last night up to 79.9" on the year.

Some heavy graupel here tonight

Since I finally got over 1k subs I am able to livestream on youtube now! I did my first tonight with some intense LES off Erie. Got a good clip of some thundersnow!

Windy today with some LES setting up across southern tier and tug