Interesting Wintry Days Ahead
January 7th, 2009 at 10:40 pm by Don Paul under Weather Watch 4
After the near term lake snow, snow showers and blowing snow, we still have questions about whether Saturday’s snow will add up to anything significant. NCEP’s own NAM, which was tossed aside today in their analysis, does still show some moderate snow over WNY during Saturday. The only other model showing the storm system that far north with significant snow is the less reliable and low res Navy NOGAPS. The GFS and Euro both keep light to moderate snow mostly south of the metro area, and the UKMET shows us getting very little as well. Ensembles, in general, aren’t showing that much snow for us on Saturday, either. However, there is fairly good agreement on a Very Cold outbreak developing by Tuesday with gusty winds and shifting lake snows. This will be the coldest airmass of the season thus far and, if model trends hold, the wind chills may be brutal at times. It’s impossible to time or locate any lake snow bands at this time.
Sorry Don, I had not thought about those events. I guess I was mostly thinking about ones that ended up much more severe or much less. I must say, though, that even in my lifetime (14 years), lake effect predicting has greatly improved.
Let’s keep in mind,everyone, that with the severly cold windchills forecast,a major lake snow event could be a dangerous for those who have to travel or work outside.Sure,to some a huge snowfall is a great thing, but let’s keep in mind the seriousness of the potential effects.
Thanks Don and Nick, On some level I knew Cold air is more dense than warm air.
Lakewood, I hope your wrong about next week being the lakes “last gasp for air.” But I think your going to be right. I remember Don saying that the last few degrees take longer to loose. Lets just hope the final two degrees can last through next week. Probably a long shot.
When it comes to the Luge, I’m all set with snow. I really could use another 6 inches or so to make it perfect and it looks like I’ll get that soon. Now lets just hope for no MAJOR warm-ups. (TIL MARCH)
Sled Hill,
Another problem with very cold air has to do with the snowflake type. The limited moisture available with a cold airmass will produce a type of snow “flake” that looks like a single column rather than the classic 6 pointed flake. The 6 pointed flakes (called dendrites) can pile up more easily than a bunch of columns. That is, a very cold airmass which does produce snow will not add up as quickly as a warmer airmass due to the type of snow that’s falling.
Imagine dropping 1000 sewing needles into a bowl and measuring the needle depth, and then dropping 1000 small feathers in to the same type of bowl and measuring feather depth. The feathers would obviously pile up more quickly. This isn’t the greatest analogy, but it should get the point (ha ha) across.
Roughly a good range in temperature aloft for decent snowflakes is
-10 to -22C. For ideal conditions, you’d want the snowflake formation to be in a more narrow range: -12 to -16C. The problem with late next week is the fact that we’ll probably be dealing with temperatures aloft below -22C, which produces these column-type “flakes”.
I’ve used quotes around the word “flakes” above on occasion, as I should be referring to ice crytals, but it’s a bit easier to understand if I just say flake.
z
http://www.its.caltech.edu/~atomic/snowcrystals/class/class.htm
Everything you ever wanted to know about snowflake types
so mr “z” are we getting a major event LES or no? :O
Ayuud, overall evolving pattern for next week would favor the potential for a big lake effect event….east/southeast of Lake Ontario, but even that’s highly uncertain nearly a week out.
Z, Once again thank you. You are very good at explaining things in laymens terms. I would rather sled on feathers than sewing needles any day! haha
“WHILE IT IS TOO EARLY
TO GIVE DETAILS REGARDING THE POTENTIAL LAKE EFFECT SNOW…THE RIGHT
COMBINATION OF LOW LEVEL MOISTURE…FAVORABLE WIND SHEAR AND SNOW
GROWTH COULD RESULT IN IN SIGNIFICANT LAKE SNOWS IN THIS ARCTIC
PATTERN.” NWS forecast discussion– long term wed-fri
There are still no obvious signs of a major lake snow event in the Buffalo metro area during this outbreak, due to the modeled wind forecasts–but I’m still doing my analysis and will have more later. Somewhere along the line, though, there will be–in addition to the synoptic snow associated with the transition to this very cold pattern–some shifting lake snows which should at least make brief visits to the region.
Does anyone know if the niagara ice boom affects ice cover on lake erie and to what extent?
Z, you mentioned that conditions may be favorable for a big lake effect event east and southeast of Lake Ontario, what about Lake Erie?
Thanks in advance Z!
The clevand discussions on NWS are saying major lake snow event off Erie possible thur.”THE STORM SYSTEM WILL BE FOLLOWED BY A STRONG ARCTIC HIGH PRESSURE
DRIVING BITTERLY COLD AIR INTO THE FORECAST AREA. THE LAKE EFFECT
SNOW MACHINE WILL LIKELY KICK IN WITH THIS FEATURE AS IT MOVES INTO
THE REGION ON THURSDAY.”
z,Thank you for that interesting info on snowflake types. I learn so much on this blog!!
Juju, please refer to Don’s recent post. I’ll occasionally provide some science tidbits when time allows, but I’d prefer to leave Western NY forecast questions for Don.
Even wed there could be signifant accum, but they arent clear if its general or lake. I think they sre hinting at a lot more moisture being drawn in with each passing and strengthening low, each one potentially getting colder and stronger, drawing plenty of gulf moisture
Don,
NWS @ 10:45 this am says Lake snow could reach south buffalo by late afternoon..anything for the Metro? Just called the weather line and did not hear an update, so thought I would give you a line….Thanks
Z, thanks again. The only reason I asked was because you mentioned lake ontario could possibly have the potential for significant lake effect snow, so I read it as there are no signs pointing to the same for lake erie, just because you didn’t mention lake erie. Now I know why you didn’t mention lake erie.
Here are the accuweather snowfall predictions for fri-sun
http://www.accuweather.com/news-story.asp?partner=accuweather&traveler=0&article=0
Sled Hill you might love this one!! Lake Erie wind forecast guidance (NOAA)
http://tidesandcurrents.noaa.gov/ofs/leofs/fore_wind.shtml
Here’s a thought based on common sense. (I think) Since we’re going to be so cold next week, I would assume the wind will be out of the NNW most of the time thus leaving most of the LES south of Buff and S towns. Don said so far no major out-break, and Z said SE of Lake Ontario. Maybe with a passing low we could see a shift north, but for how long? And, if the air is that cold, (dense) how can it hold that much moisture? Just a thought from my very untrained mind.
The Cleveland discussion is irrelevant for the Buffalo area in that their lake snows are driven on a more WNWly boundary lyr flow.
I’ll have more on a new thread between 2 and 2:30.
Weatherline has been updated.
Don,
Thanks, I got the update on 844-4444, is that LES POSS for the METRO Mon?
I guess being ahead of the storm there is a chance?
Thanks Don, I don’t want to crowd you with too many what if questions, just looking for clarification…
Little Igloo, The cleveland office covers the lake erie shores up to about Erie P.A. I think. They can have major lake effect events at times when we don’t. Actually when they do we generally don’t because those areas are impacted by North to northwest flows. So I’m not sure if we should get excited by that assessment from Cleveland. Also I’m not sure we want strong high pressure either since the air will be sinking. However I’m just speculating on these matters!
Those snowfall predictions are well in line with what Don said. Very cool link on L Erie wind directions. Looks like most of the time they are out of the West, then NW, then NE. No WSW at all. Maybe a very little.
Sled Hill,
That was only through tomorrow, But you are in line for about 2-4 inches today per Don’s latest update for the LES shifting a bit northward this afternoon…
Let’s hear what Don has to say by mondays forecast regarding wed-fri’s passing lows. Im guessing(yes guessing) that warnings will start to get posted by then.
with such cold air and possible moisture content, could high pressure still produce lake snow? I thought it could….
Thanks thinksnow08, I need to catch a current forecast. I’ve been working and following the blog. Time to get an update I guess. Are we going to get snow today? Last night Devin and Don said no snow for my sledding party tonight. Snow acts like sand on ice and slows us down alot. I hope it holds off til 10-11pm.
According to today 12z run gfs model output in bufkit
friday looks the best chance for LES in the metro area
http://i43.tinypic.com/51u4o2.jpg
Don, Just listened to the weather line and got an update. So much for a snow free sled party. I saw those snows shifting earlier and thought they would deminish before they reached us. Guess not.
What time is the sled party? : )
6pm. Under the lights!! Come on over!
Did you know that if the inside walls of an Igloo are smoothed out you will not get dripped on?
Little Igloo,
How old are you? If you are young, I think your enthusiasm is well received, we are ALL learning, if your older, you need to filter some of your comments or questions better, Don only has time for so much and others do not want the site cluttered with just any post…I know from experience, been told many times…If you want to talk to Sled hill about certain things go to the other post, that is why it it there…Thank You
That’s correct. This blog is already overactive at times, and the sled stuff needs to go on the other thread, please.
NEW THREAD IS POSTED. AGAIN, PLS KEEP RECREATIONAL ITEMS WHERE THEY BELONG.
Please also watch spelling and punctuation.
Even though this is a blog, if we are all learning, we must learn by correct example (Thinksnow08.)