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> 2016-17 Season Long GL/NE Lake Effect Snow Thread, Forecasts and Observations: October 15th-May 1st
NorEaster07
post Nov 17 2016, 09:24 PM
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https://twitter.com/blizzardof96/status/799436507715162113

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OhioBlizzard
post Nov 17 2016, 11:59 PM
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Haven't had the time to comment much on this one, but it looks like this event might be worthy for the first lake effect write up of the year. I'll probably try to put something together in the next 24-36 hours.

Some quick thoughts. The window for "pure" lake effect convection is probably going to be quite short for this event with amounts generally on the lighter side. The area that could see noteworthy snowfall will be the eastern lakes that remain closer to the upper level low and associated low-level moisture. Right now eastern areas of the Lake Erie snowbelt with the help of upstream support from Lake Huron as well as areas to the lee of Lake Ontario look to be in the best position, although downwind of Lake Ontario will probably have much more of a synoptic, lake enhanced pattern. Some form of headlines will most likely be needed for these areas.


--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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ohiobuckeye45
post Nov 18 2016, 11:40 PM
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WWWOOOWWWWWWWWW blink.gif


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ohiobuckeye45
post Nov 18 2016, 11:42 PM
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ohiobuckeye45
post Nov 18 2016, 11:43 PM
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This post has been edited by ohiobuckeye45: Nov 18 2016, 11:43 PM
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ohiobuckeye45
post Nov 18 2016, 11:44 PM
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OhioBlizzard
post Nov 19 2016, 03:49 AM
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Put together some of my thoughts for the upcoming lake effect/enhanced snowfall event for 11/19 through 11/22. Pardon any sloppiness in format, I did not have time to go back and edit/clean things up like I normally try to. Also, the discussion covers the broad synoptic scope of the event, but focuses primarily on the western to central basin of Lake Erie as this event is quite long in nature, especially over the far eastern lakes and I was short on time.

Jumping right in, a surface area of low pressure is currently progressing through the northern Great Lakes positioned northeast of the Keweenaw Peninsula at 0400 UTC with an associated cold front extending to the south across the central Great Lakes region. With the passage of the cold front, cold air advection (CAA) will affect the region quickly cooling lower tropospheric thermal profiles, steepening the lapse rates.

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Although the cold front will sweep through the region overnight through the morning, the mean low-level flow (MLLF) will still remain W-WSW during the day tomorrow with thermal profiles not sufficient for snowfall during the day. This will change however as the 500 mb level trough axis moves overhead during the late afternoon on Saturday and the MLLF veers. Thermal profiles will quickly become sufficiently cold for snowfall going through the evening tomorrow.

Attached Image


In general, the MLLF for this event should remain in the 290-320 range, allowing for a multi-banded setup to take hold. With moderate lake induced instability already in place by tomorrow evening, a lake response should quickly take hold once the flow veers. With a WNW-NW flow, the degree of low-level moisture present will be a significant factor as to how intense the lake effect is. With moisture from the upper level low (ULL) over the region tomorrow night, this period should be when the most intense snow falls to the lee of Lake Erie in Ohio. Further to the east locations across the eastern basin of Lake Erie will remain under better low-level moisture from the ULL for a longer period of time.

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The MLLF during this event will be moving along at a pretty good clip which can result in a decreased residence time for heat and moisture fluxes from the lake surface to influence the boundary layer. With a short fetch, this will probably lead to a decrease in coverage outside of the regions that are influenced by upstream preconditioning by other snow bands. One positive is that with a fast MLLF, moisture from Lake Superior/Michigan convection generally seems to hold together further inland. Type II events are generally quite dependent on topography, and with a strong MLLF (as well as a toasty lake) areas near the lake at lower elevations should not expect accumulating snowfall.

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As moisture quickly begins to pull out as the ULL shifts east (see above) Sunday morning, lake effect should quickly begin to weaken as entrainment of dry air into the developing convection lowers convective cloud heights. Thus, I would expect most of the accumulating snow to cease in NE OH by noon on Sunday, although snow showers might persist through the afternoon. Further to the northeast across the eastern basin of Lake Erie and to the SE of Lake Ontario activity will still be producing accumulating snowfall.

Overall, the heaviest amounts will certainly be across the eastern portion of the snowbelt from NW PA into SW NY. There are several factors going for this region. First, as mentioned earlier better synoptic low-level moisture will be present. In addition, upstream preconditioning from Lake Huron will significantly enhance snowfall. NE OH will not benefit from these factors other than briefly on Saturday night. I do think there will be a favorable 12-18 hr period for accumulating snowfall from roughly 00Z Sunday-17Z Sunday. Accumulations will certainly be cut by the warm ground, but still the first accumulating snowfall should be in the works for many at elevation. I’ll let the snow map explain the rest.

I did not have time to get into downwind of Lake Ontario, but suffice to say that Kurt should be able to get some snowmobile play in if he wants to. I think the sweet spot there will probably be somewhere on the western tug where the best combo of synoptic moisture, lake enhancement, and orthographic up-slope occur.

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This post has been edited by OhioBlizzard: Nov 19 2016, 03:54 AM


--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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JoeyD
post Nov 19 2016, 06:25 AM
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QUOTE(OhioBlizzard @ Nov 19 2016, 03:49 AM) *
Put together some of my thoughts for the upcoming lake effect/enhanced snowfall event for 11/19 through 11/22. Pardon any sloppiness in format, I did not have time to go back and edit/clean things up like I normally try to. Also, the discussion covers the broad synoptic scope of the event, but focuses primarily on the western to central basin of Lake Erie as this event is quite long in nature, especially over the far eastern lakes and I was short on time.

Jumping right in, a surface area of low pressure is currently progressing through the northern Great Lakes positioned northeast of the Keweenaw Peninsula at 0400 UTC with an associated cold front extending to the south across the central Great Lakes region. With the passage of the cold front, cold air advection (CAA) will affect the region quickly cooling lower tropospheric thermal profiles, steepening the lapse rates.


Although the cold front will sweep through the region overnight through the morning, the mean low-level flow (MLLF) will still remain W-WSW during the day tomorrow with thermal profiles not sufficient for snowfall during the day. This will change however as the 500 mb level trough axis moves overhead during the late afternoon on Saturday and the MLLF veers. Thermal profiles will quickly become sufficiently cold for snowfall going through the evening tomorrow.


In general, the MLLF for this event should remain in the 290-320 range, allowing for a multi-banded setup to take hold. With moderate lake induced instability already in place by tomorrow evening, a lake response should quickly take hold once the flow veers. With a WNW-NW flow, the degree of low-level moisture present will be a significant factor as to how intense the lake effect is. With moisture from the upper level low (ULL) over the region tomorrow night, this period should be when the most intense snow falls to the lee of Lake Erie in Ohio. Further to the east locations across the eastern basin of Lake Erie will remain under better low-level moisture from the ULL for a longer period of time.

The MLLF during this event will be moving along at a pretty good clip which can result in a decreased residence time for heat and moisture fluxes from the lake surface to influence the boundary layer. With a short fetch, this will probably lead to a decrease in coverage outside of the regions that are influenced by upstream preconditioning by other snow bands. One positive is that with a fast MLLF, moisture from Lake Superior/Michigan convection generally seems to hold together further inland. Type II events are generally quite dependent on topography, and with a strong MLLF (as well as a toasty lake) areas near the lake at lower elevations should not expect accumulating snowfall.


As moisture quickly begins to pull out as the ULL shifts east (see above) Sunday morning, lake effect should quickly begin to weaken as entrainment of dry air into the developing convection lowers convective cloud heights. Thus, I would expect most of the accumulating snow to cease in NE OH by noon on Sunday, although snow showers might persist through the afternoon. Further to the northeast across the eastern basin of Lake Erie and to the SE of Lake Ontario activity will still be producing accumulating snowfall.

Overall, the heaviest amounts will certainly be across the eastern portion of the snowbelt from NW PA into SW NY. There are several factors going for this region. First, as mentioned earlier better synoptic low-level moisture will be present. In addition, upstream preconditioning from Lake Huron will significantly enhance snowfall. NE OH will not benefit from these factors other than briefly on Saturday night. I do think there will be a favorable 12-18 hr period for accumulating snowfall from roughly 00Z Sunday-17Z Sunday. Accumulations will certainly be cut by the warm ground, but still the first accumulating snowfall should be in the works for many at elevation. Iíll let the snow map explain the rest.

I did not have time to get into downwind of Lake Ontario, but suffice to say that Kurt should be able to get some snowmobile play in if he wants to. I think the sweet spot there will probably be somewhere on the western tug where the best combo of synoptic moisture, lake enhancement, and orthographic up-slope occur.


Another great detailed write-up OHBLizz!!

It's going to be quite the contrast from yesterday's and the current (as of 6:00AM) weather. CLE did bump up the snow totals a bit overnight for portions of NE OH.


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Residing 1235' up a north facing slope, where the highs are low and the lows are high.
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Mike W IN herkim...
post Nov 19 2016, 08:10 AM
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I guess I should show some love to this thread biggrin.gif Nice write up as usual Ohio, you definitely help keep this thread going..

From pro met lake effect king

QUOTE
That map looks great for locations, and as you say....more to come after....but I'm thinking the totals overall, will be much higher for the higher elevations....ratios will be higher, and the upslope forcing will significantly add to the totals for this event...Chautauqua Co. will have jackpot totals over 2'...Tug Hill Area, near 3'....Hills S, SE, and SW of SYR, near 2'...Fulton, 20"...SYR, 18"....ROC 12"....BUF....3"(Unless the Huron band visits for a bit...)....The writing is on the wall....this will over-produce for many vs. model consensus....Happy kick-off to winter '16-17'!!!!! If I have time....maybe a map later.....



One more note....the wind will be ferocious for a time Sun. into Sun. night along the S/SE/E. Shore of Ontario....Blizzard criteria will certainly be met for some!!!


QUOTE
....and another thing to note...smile.gif

The EQ levels will be nearing 12K....and snow growth zone may well grow to 5K or so thick!.....or nearly double what we typically get in decent LES setups....

Look for 3-4"/hr. rates off Ontario Sun. night....even with multiple bands....but there will, of course be a primary band of convergence meandering about S. Oswego/N. Onondaga Cos.




--------------------
Seasonal Snowfall 95/96-Current

2016-2017 Snowfall 160.2
2015-2016 Snowfall 106.2"
Source

Top 5 snowiest winters of the past 20 years

1)95/96- 273.9"
2)03/04- 255.4"
3)10/11- 247.3"
4)00/01- 244.0"
5)06/07- 232.6"

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Mike W IN herkim...
post Nov 19 2016, 08:27 AM
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Good illustration of the wind direction needed off Ontario, 290-300 is right in my wheel house..


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--------------------
Seasonal Snowfall 95/96-Current

2016-2017 Snowfall 160.2
2015-2016 Snowfall 106.2"
Source

Top 5 snowiest winters of the past 20 years

1)95/96- 273.9"
2)03/04- 255.4"
3)10/11- 247.3"
4)00/01- 244.0"
5)06/07- 232.6"

My PWS
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ohiobuckeye45
post Nov 19 2016, 09:26 AM
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another monster GFS run for NY

This post has been edited by ohiobuckeye45: Nov 19 2016, 09:27 AM
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NorEaster07
post Nov 19 2016, 10:04 AM
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QUOTE(Mike W IN herkimer @ Nov 19 2016, 08:27 AM) *
Good illustration of the wind direction needed off Ontario, 290-300 is right in my wheel house..


Attached Image


That's cool to see! My sister lives in Belfast, NY (near Cuba), I'm still wondering why they always get less than others. Are they sheltered by tall hills to the West? Is it just too far for big Lake Effects?

She is at the marker. BTW, about to experience the change

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OhioBlizzard
post Nov 19 2016, 04:37 PM
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QUOTE(JoeyD @ Nov 19 2016, 06:25 AM) *
Another great detailed write-up OHBLizz!!

It's going to be quite the contrast from yesterday's and the current (as of 6:00AM) weather. CLE did bump up the snow totals a bit overnight for portions of NE OH.

Thanks JD! Shock to the system for sure after yesterday!

QUOTE(Mike W IN herkimer @ Nov 19 2016, 08:10 AM) *
I guess I should show some love to this thread biggrin.gif Nice write up as usual Ohio, you definitely help keep this thread going..

From pro met lake effect king

Thanks Mike and enjoy the snow out your way!


--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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OhioBlizzard
post Nov 19 2016, 04:44 PM
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QUOTE(NorEaster07 @ Nov 19 2016, 10:04 AM) *
That's cool to see! My sister lives in Belfast, NY (near Cuba), I'm still wondering why they always get less than others. Are they sheltered by tall hills to the West? Is it just too far for big Lake Effects?

She is at the marker. BTW, about to experience the change


The prime reason is they are too far from the lake generally to consistently get into lake effect activity, although they still get their fair share there I'm sure. Miss out on the big SW events to the south and generally too far from the lake for the WNW-NW events. A westerly MLLF is probably the sweet spot for that location. Downsloping from the higher elevations to the west probably reduces totals a bit as well in general.


--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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OhioBlizzard
post Nov 19 2016, 04:47 PM
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Current loops. Click on regional loop for animation.

Attached Image


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This post has been edited by OhioBlizzard: Nov 19 2016, 04:48 PM


--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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OhioBlizzard
post Nov 19 2016, 05:06 PM
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Cool setup currently ongoing. The influence the synoptic system is having downwind of the lakes currently is quite clear as their is a marked difference in echo intensity associated with that of lake enhanced snow, versus that which is more of pure lake effect origin. A lot of the activity in northern lower/UP is lake enhanced snowfall. Visible and IR satellite below.

EDIT: Had sizing issues. Hopefully this is better.

This post has been edited by OhioBlizzard: Nov 19 2016, 05:17 PM
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--------------------
Great Lakes Lifer. Lake Effect Enthusiast. Earth's Most Unique Subregion. ...Its the Lake Effect.

Average Seasonal Snowfall IMBY: 92.3"
Updated for 2016-2017: Last Update 10-28-2016
2016-2017 Winter Total Thus Far: 0.0"
Current Snow Depth: 0"

Significant Events:

2015-2016 Winter Total: 52.3"
2013-2014 Winter Total: 97.5" --------------- 2014-2015 Winter Total: 72.0"
2011-2012 Winter Total: 56.0" --------------- 2012-2013 Winter Total: 64.2"
2009-2010 Winter Total: 91.1" --------------- 2010-2011 Winter Total: 130.0"

Best of 2010-2011 Winter Pictures are here! "A Year To Remember"
http://forums.accuweather.com/index.php?showtopic=25851
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NorEaster07
post Nov 19 2016, 06:41 PM
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Lake effect Thundersnow?!

https://twitter.com/GregDeeWeather/status/800119285871939584

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NorEaster07
post Nov 19 2016, 07:00 PM
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ErieWx
post Nov 19 2016, 07:13 PM
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We had one rumble of Thundersnow. smile.gif I'm too close to the lakeshore in western Erie PA for this event, but we have a dusting & it's been snowing on and off all day.
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Ilovelakeeffect
post Nov 19 2016, 09:02 PM
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We've had borderline whiteoutsnows for a little over an hour now. Probably about 1.5" on the ground so far and still coming down. Streets are all covered too!

This post has been edited by Ilovelakeeffect: Nov 19 2016, 09:03 PM


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Hey Accuweather! Please send us our very own Great Lakes, Ohio Valley, Midwest blogger. Heck, with the Lake Effect alone, our winters can be more interesting than many other locations around the country not to mention the synoptic snowfalls.

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