Late Wednesday Evening Update
No major changes from my earlier forecast. A bit of lt mixed precip may reach WNY during Thursday afternoon. Lt Snow is currently streaking north from Kentucky, but temps may warm just enough for it to begin as a mix. A little burst of snow is likely in the predawn hours of Friday, accompanying the passage of the cold front--maybe a quick 1-2" just in time for the Friday AM drive. A punch of drier air will thin out those snow showers early Friday. Gusty SW winds will develop, but the cold inflow will be fairly dry, and any afternoon lake effect near the metro area looks to be limited, but extending inland toward Batavia from near Buffalo. A little more moisture may enter the flow Friday night, with this limited lake snow staying approximately in place during the evening, and possibly shifting north after midnight as winds back to more of SSW flow ahead of the low pressure system moving our the way. The cyclonic curvature of that low will produce enough wind shear to break up any organized lake snow by Saturday morning, but snow showers should bring modest accumulations across much of WNY during Saturday until later in the day, when winds veer to WNW. The WNWly flow will bring lake snow into ski country & the srn tier, but from that direction we tend to get multiple bands of lake snow, rather than a single, well-organized band. (A due westerly flow would bring more substantial accumulations to the ski slopes). This WNW flow will continue on Sunday, which will be a fairly bitter day when you factor in the brisk breeze. Sct Lighter Snow Shwrs w/limited sun on Sunday for the metro area, and some occasionally significant lake snow in the hills and well NE of Buffalo (ern Niagara, Orleans, & Gen Cos). These multiple bands will be coming in from Lakes Erie, Ontario & Huron.
The NAO now looks to be neutral most of the time for the next 2 weeks, and PNA will be weakly negative. That makes a prolonged cold wave much less likely.
Today and tonight's model runs have made the lake effect potential for Monday much less impressive.
The NAO now looks to be neutral most of the time for the next 2 weeks, and PNA will be weakly negative. That makes a prolonged cold wave much less likely.
Today and tonight's model runs have made the lake effect potential for Monday much less impressive.
posted by Don Paul at
11:08 PM
29 Comments:
So it doesnt look like a ALOT of snow will fall all at once BUT it may add up over the weekend into early next week, addind the usual anything can happen..
Great Blog , looks like needs a little cleaning but nice work..
So it doesnt look as though we will see much snow here in the north towns. You say that this probaly wont be a pro-longed cold snap, and that the models seem to be down playing the lake effect snow potential. If your someone who likes winter weather (snow)... is there anything I/ we can look forward to? Im sorry, but this has been such a lame winter for snow lovers so far! Thanks for the update... and I hope this LES for some reason or another proves you wrong... just for the shear fact that I along with many others are wanting snow so bad! With lake effect snow... we all know that its somewhat harder to predict... so we'll keep our fingers crossed! Thanks again and keep up the good work!!
Any change on the model runs for today on this Thursday? Does it look like a better chance for LES, or is it looking less likely and less impressive if it does in fact form? Any new developments/ changes for people who want snow here in the North towns? As always -Thanks!
Don,
How long do you think this cold snap will stick around? you have any dates when expecting warm up? Any chance the lake will freeze over this year?
Thanks, you's are great
Morning model runs show little change. Any lake snow which develops Friday afternoon will be weak, with very dry air punching in. What there is of any weak lake snow would develop from near Buffalo to Batavia, and possibly shift north late Friday night due to backing of the winds to a SSWly flow ahead of that Saturday low pressure system. Even after passage of that low, the WNW flow later Saturday into Sunday is not ideal for the heaviest accumulations in ski country & the srn tier. They'll get some help from nature, but not as much as they would with a Wly flow.
The coldest of the cold air will be with us on Sunday, with a little moderation again early next week. With a moderate la nina, a neutral NAO, neutral to weakly negative PNA and a mostly positive AO all working against prolonged cold spells, we're more likely to see "shots" of cold air. However, the 2nd half of January does look colder than the extraordinarily mild first half. As of this morning, our monthly temperature is an amazing 10 degrees above normal, and snowfall is about -9".
Our 12z and 18z runs of Super Microcast are showing a band of lake enhanced snow forming ahead of the Saturday low pressure system across Buffalo & suburbs to the N & NE (maybe srn Niag & Orleans, along w/nrn Gen Cos). It won't be much, but could bring localized accum of 2-4" from the predawn hours through late Saturday AM, before winds veer later on Saturday to a WNWly flow.
better than nothing!!! amherst will take it!
Don i am an avid snowmobiler and groomer operater for a snowmobile club in Catt.Co. Is there a chance that the southern tier could see up to a foot on snowfall by monday morning? How about chances for snow next week? You didnt mention anything about snowfall chances at 6. I'm just wondering if that was because chances are not good or if you were running short on time with the rest of your forcast. Keep up the good work. You and your team are by far the best tv mets in the area.
Mike,
In answer to your questions, it was a bit of both; short on time and nothing huge coming so far in guidance for next week.
As for accum this wknd in the srn tier, a flow from the WNW tends to favor multiple, less well organized bands. A flow from 265-270 would bring organized lake snow into the nrn halves of Chau & Catt Cos, but a flow of 280-290 means a shorter fetch over Lk Erie, and less potent lake effect. The latter is what we're currently looking at from Saturday afternoon into at least Sunday morning. There might be some backing to 270 later Sunday. The best chance for a foot will be along the NE to SW Chautauqua Ridge, because the wind will be coming in perpendicular to that ridge, forcing more lift and convergence of the limited moisture into snow. Also any westward facing slopes should pick up at least several inches. But, once again, current computer guidance doesn't shape this up to be a huge snow maker, even in the srn tier.
Don and MB,
Pardon my ignorance, but what are the "ideal" conditions for lake effect? I realize that there are probably too many variables to list all and too many complexities to even address in a graduate course let alone a blog, but are there certain generic factors (wind speeds, upper air/lake temperatures, dew points, etc...) which improve the likelihood of lake effect?
As always, I look forward to your thoughts-Matt
Matt,
Here are a few of the variables. Ideally, there should be a temperatures dropoff of at least 13degrees between the lake surface temperature and the temperature at 850mb pressure surface, or about 5000 feet. Winds should be well aligned, with less than 30 degrees change in direction from the surface up to 850mb, and not much directional shear from 850mb to 700mb (10k feet). There should be adequate humidity/ice crystals in the air aloft for dendritic crystal growth to occur. There shouldn't be too much speed shear either (that is, winds that are too strong are distuptive to some extent before lake bands form, even if well aligned. Once lake bands form, they often can withstand greater boundary layer speeds because the convergence of moisture is already in place.
If there is curvature to the winds, it is better for it to be cyclonic rather than anticyclonic. But in both cases, if the curvature/directional change is too great, that is disruptive to band formation. Air above, say, 3000 feet which is sinking or very stable will inhibit the development of lake bands, because this creates a capping inversion that stops vertical development.
Those are just some of the factors, off the top of my head. I believe the NWS Buffalo site has a good primer on lake effect, if you want to take a looksee.
Its hard to believe we have not had a big scale LES event yet this winter. And the lakes that should be frozen this time of year are not! We really havnt had a good snow storm ever since the Oct. storm snowfall of around 2 feet. We are so over-due for a big snowfall... and it looks as though it wont happen any time soon. Bad news for snow lovers, thats for sure!
Jim,
In case you forgot, we had a foot at the NWS and up to 18" in Niagara County on December 16th.
I did not forget about that! I have lived in WNY all my life, and 18" of snow in a rather small part of Niagara county is nothing like snow events we have had in past years, mabye 5-6 years ago. Back then we would get big snow storms, much bigger than any we have had in the past few years (leaving out the oct storm, and 1 or 2 LES events in the S. towns)
We're due for "a good one"... and in my mind, the 18" of snow up in Niagara county was not like snow storms measured by the foot like we used to have in past winters. What ever happened to the real good snow storms we used to get at least once or twice a winter?
When it all comes to the bottom line, winters just arn't like they used to be. We may get some snowfalls of 18" in a small part of the viewing area, but when that 18 inch snowfall is compared to large-scale snow events we had 5-6 years ago... that 18 inch snowfall simply woulnt be classified as a "large-scale event." In winters from 3-4 years ago up to now, that 18 inch snowfall would be considered a "large snowfall."
The Bills, Sabres and Winter are over... No more snow...
Thanks Don and MB for doing a great Job! MB, I wish we could get a big LES storm!
Lake Effect info I think Don was talking about:
www.erh.noaa.gov/buf/lakeffect/indexlk.html
I must agree , we in Buffalo are seeing Global Warming or are in a very long warming trend ( years not days) , 1 or 2 winters ago , It rained pretty much all of Winter season ( I think)
Anyone who doesnt't think 18 inches of snow is a lot needs to have their head examined!
I can hardly remember a time when storms by the feet were a COMMON occurence. Yes, they happened once in awhile but not frequently.
I just think a lot of the people on here were younger and smaller which made the storms seem bigger.
Things have changed this much over a 5-6 year period... makes you wonder! Buffalo has been known for its snow and LES. 18 inches of snow is by no means a "big one" for us, I totaly agree with you Jim. We used to get much much bigger snow storms measured by the foot!
-Adam
Soprano, winters have progressivly gotten "lamer" over the past few years. Snow storms measured by the foot were much more common 5-6 years ago, look at the data if you beg to differ. They were by no means a "run-of-the-miill" occurance though. We used to get at least one or two of those big ones per winter back then. Now-a-days, we look at 18 inches as being the mother of all snow storms... things have changed...
I also agree with Jim and disagre with Soprano person.
We used to get big storms.
When was the last time the N.Towns saw a snowfall of a foot and a half or more? Not within the past few winters! It is true 5 to 6 years ago, places such as Amherst would see a few big snow-falls a winter. In todays time, snow-falls such as that have not happened for quite some time now!
Steve
18" used to be nuttin.
Now all news stations go crazy even of we get 4".. It's kind a like all that spendin goin on..
Peoples use banks money to spend way ova their means and now we have this mess. We need a correction in our expectations.We need 2 weeks of heavy snow like we used to get in the old days and then 18" would be 18" not 5 feet.
I agrees with Jim too.. foregtaboooutit
Ok... say a "big snowfall" is 2 feet or more. In the winters of 1992 up to 2002, we have had many "big snowfalls." Nowadays, we dont see as many big snowfalls... if any. When you think about it, last winters big snowfall was the Oct storm snowfall, and that wasnt even offically in winter! So Your flat out wrong if you think winters are the same as they have always been! Things have changed. thats for sure!
Don, I was wondering what the chances are at this juncture for somewhat more organized lake effect for later monday into tuesday. I looked on the noaa website at the wind direction and it was showing a shift more south-westerly winds for atleast eight to ten hours or so during that period. I understand that Friday their will be drier air and possible wind shear on saturday that would cut down the chances of significant lake snow, but will this be the case for monday? If you get this could you let us know on the 11:00 newscast?
Don,
Would you consider 18 inches a lot of snow for a single storm?
I think what everyone is failing to realize is that after we get 18 inches of snow (like the Dec storm) its melts..there isn't another storm following and the snow does not tend to pile up...thats why it seems like we do not get any big storms anymore.
Don is in the media. His job is to hype it up and up. So Don's going to say it is a lot.
I think AL was right from Buff news..Great article//
Not giving Don much credit are you. I think he will answer it honestly.
Of course Don is in the media, and it is his job to deliver an accurate forcast based on several computer models that update daily, possibly several times a day, I dont know. The hype part is not "embelishment" at all. Yes, Don wants to draw a larger audience by giving us "tid-bits", but he is doing so by delivering the most current information to us. If it means taking a chance by giving us inferences into a longer range forcast than any other station even comes close then thats great. As for your buffalo news article- Al just needs to get his 500 words in, and he didn't have anything else to write that day.
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