OHweather

There's been pretty persistent banding for 6-7 hours (with a brief exception around 11PM) across eastern Lake County, the chimney of Geauga County and the northern 2/3rds of Ashtabula County. It took a little longer to develop but there's also now good banding into most of inland Erie County PA and northern Crawford County PA. Hopefully MAIDEsNow wakes up to a good total...as of right now it looks pretty good near Edinboro. I think with perhaps along the immediate lakeshore in NW PA that my forecast should do pretty well, but we'll see what totals actually come in in the morning. Did get a couple of snow showers that produced a whopping 0.1" of snow here in NE Summit County...my first measurable snow of the season

OK...here it is This will be a fairly short duration lake effect event, with around 24 hours’ worth of potentially decent lake effect snow, along with two surface troughs moving through and affecting the wind field at times. Conditions will be favorable for moderate to heavy snow Friday afternoon through Saturday morning, however the potential for any banding to shift around may limit accumulations somewhat. With a mainly west wind, this lake effect event will affect only a small portion of the primary NE Ohio Snowbelt, with more of NW PA and SW NY being affected. The first fairly potent mid-level shortwave and associated surface wind shift will move through late Friday afternoon/early evening. Winds will go WSW or even SW Friday morning and afternoon ahead of this shortwave, so any lake effect will initially be carried into SW NY. An increase in moisture and steepening lapse rates beneath the shortwave could cause a few snow showers anywhere late Friday afternoon, but accumulations will be very minimal outside of the lake effect snow. As this shortwave passes, moisture will increase over the lake and lake induced instability will increase quickly late Friday afternoon as mid-level temps cool. By Friday evening, BUFKIT forecast soundings for Erie show good moisture to above 10k feet, with equilibrium levels near 15k feet, well aligned westerly winds and strong omega (upward motion) through the snow growth zone. These favorable parameters for heavy LES along with convergence developing over the lake and pushing inland as the surface trough goes by and brings winds around to the west during the evening should result in a band of heavy snow developing and pushing inland late Friday afternoon and evening, first in Erie County and then in Ashtabula and Lake Counties. The NAM and Euro briefly show winds going almost due west overland Friday evening behind this first trough, with more WNW winds aloft near 850mb, per the above NAM forecast sounding from CLE. The stronger, more WNW winds aloft will mix to the surface over the lake, causing convergence to persist along the shoreline. With slightly south of due west winds persisting over land, any band will struggle to push too far inland. The stronger, more west or WNW winds over the lake may push any band inland enough to affect far NE Cuyahoga County and northern Geauga County for a time mid to late Friday evening behind the surface trough, but with high pressure trying to build in over land and a very strong lake to land temp differential resulting in a decent lake aggregate trough, I can’t imagine any band getting south of around US 6 for any length of time Friday evening. The models show another mid-level shortwave (more of a vort max) moving through during the wee hours on Saturday, with another surface trough. This will likely cause winds to back some overland to a more SW direction after midnight Friday night, while stronger, more west winds persist over the lake. This will allow convergence to remain strong in the northern Snowbelt, keeping any band going and likely well-organized, but the shift in winds over land will likely cause the band to shift north/become more focused across eastern Lake, northern Ashtabula and Erie Counties for a few hours after midnight Friday night. Behind the second wind shift early Saturday, moisture becomes becoming a bit more limited, and warm air advection begins occurring, so instability will slowly decrease…however, the above sounding from near Ashtabula valid 7AM Saturday off of the 0z NAM still shows deep moisture to above 850mb, with implied lake-induced equilibrium levels over near 700mb…so although snow intensity will probably start decreasing some by Saturday morning, moderate to locally heavy bursts of snow will likely continue into Saturday. Winds over land struggle to even come around to due west Saturday morning behind the passage of the second trough, so any snow will likely remain confined to extreme NE Cuyahoga/northern Geauga Counties points north. Winds stay in a similar direction through Saturday afternoon, so any snow may not shift a ton on Saturday…however as warm air advection continues and ridging continues building in, snow intensity should decrease. Temps over land warming several degrees and shear increasing some due to the ridging building in Saturday afternoon should also cause convergence to weaken some. Basically, although flurries could well continue in Erie County into Saturday night, significant snows should end Saturday afternoon. As for snowfall amounts and placement…the snowband that will push into the northern Snowbelt with the first trough late Friday afternoon and into the evening could be very intense. A very deep layer of moisture/instability combined with decent low level convergence and some synoptic lift from the passing shortwave could result in snow rates exceeding 2” per hour under the band. Lake to 500mb temp differentials could approach 45C for a time Friday evening which easily supports thunder and lightning in the band. This band will likely initially move into Erie, northern Ashtabula and eastern Lake Counties before settling south a little farther…potentially as far south as extreme NE Cuyahoga, central Geauga, southern Ashtabula and northern Crawford Counties for a brief time mid-late Friday evening…before winds on land back and shift the band a bit farther north. Even if the band moves south of parts of Erie County, pre-seeding form Lake Michigan along with orographic lift should keep some snow going, especially in the higher terrain Friday evening. Instability and moisture depth decrease a little late Friday night ahead of the second little trough but still remain favorable for decent snow…and convergence should remain strong due to winds backing over land but remaining stronger/more westerly over the water. This should allow snow rates of 1-2” per hour to continue under the stronger banding, although the potential for rates greater than 2” per hour will likely be lower than with the initial push of the band Friday evening. As the winds back over land, the band will likely become refocused across eastern Lake, northern Ashtabula and Erie County later Friday night. The band may nudge back south Saturday morning, but probably not any farther south than what occurs Friday evening. The band should then starts slowly becoming more disorganized and weakening Saturday afternoon, with snow ending Saturday night. Really don’t see much accumulation south of a line from Bratenahl to Mayfield to Orwell to Andover in NE Ohio. With the banding possibly getting into northern Geauga, extreme NE Cuyahoga and southwestern Lake Counties a couple of times, could see accumulations of 1-4” in these areas…with the best bet of 4” in the higher terrain in northern Geauga County. Could also see 1-4” in southern Ashtabula County, with lightest amounts closest to the Trumbull County boarder. Amounts should increase quickly farther northeast up the shoreline where banding will be more persistent…and also where the banding will likely coincide better with the best lake effect parameters. Expect some areas to see over 6” in eastern Lake County and quite possibly northern Ashtabula County too into Erie County. Exactly how much more than 6” and where exactly the heaviest snow occurs are the main questions. With fairly strong winds over the lake that are due west or slightly north of due west, think the heaviest snow is slightly inland from the lake. In addition, snow ratios inland should be 15-20:1 due to good instability/moisture/lift in the snow growth zone, but warmer temps over water and along the shore should result in lower ratios near the shore. Drier/warmer air works in from the southwest later on Saturday so the snow in NE Ohio will cut off before the snow in Erie County does, and Erie County will see the band push in slightly earlier late on Friday. Erie County also has a longer fetch and more terrain than most of Lake/Ashtabula Counties. Given these factors, do expect heavier snow in Erie County than in Lake or Ashtabula Counties. Given a good 15 hour window of potential 1-2” (at times higher Friday evening) rates beneath the band in Erie County, followed by another 6-9 hours of lighter but potentially still accumulating snow Saturday late morning and afternoon, and the likelihood that banding affects parts of Erie County for much of that window, expect snow totals to surpass a foot in parts of Erie County, likely a bit inland from the lake. Totals will drop off in Lake and Ashtabula Counties due to shorter windows and less terrain…but still, a good 12 hour window Friday evening into Saturday morning here and still some light snow through Saturday afternoon, so do expect 6-10” in eastern Lake County and Ashtabula Counties, heaviest inland from the lake.

Definitely think there's decent potential for 6-10" (locally more) of snow in Ashtabula and Erie Counties...could be a few inches in Lake and northern Geauga as well...little for the rest of us...will try to have a more detailed forecast at some point. I like the potential for a single band of snow to persist for 12-15 hours starting late tomorrow afternoon over similar areas.

The last few GFS runs and the 12z Euro both brought the winds around to WNW a little quicker Friday night and give a several hour period of moderate instability and good moisture over Lake Erie with WNW winds, which would probably allow for half decent snowfall in the primary Snowbelt late Friday night into Saturday. We'll see if that trend holds. The overall lake effect setup looks pretty good with high inversions and pretty good moisture to about 7-8k feet through the event and a long fetch...we'll see if that holds and if the wind direction cooperates. Would hate to see all the good snow go into SW NY and then see us get scraps when the winds go more WNW later in the event.

Looks like a shot of seasonable air at the end of next week (which will feel frigid after this weekend)...the GFS ensemble mean has 850mb temps of -8 to -10C and the Euro ensemble mean has 850mb temps of -10 to -12C next Friday-Saturday with a west-ish wind, so we may get some lake effect if the cold shot materializes. It currently doesn't look like a pristine setup, but some models spin up a storm to our east as the cold moves in which could potentially make the setup more decent for a brief time. Pretty good agreement on a warm up quickly following the cool down as we head into Christmas week. The ensembles try to hint at some ridging over NW Canada/Alaska (a -EPO) developing by Christmas which could get some cold in here near Christmas or a bit after, but I don't have a good feel for that potential shot yet. Odds are definitely in favor of a brown Christmas this year, although it is possible things change and we get a fluke event near Christmas as it does look like there could be transient cold shots on either side of it. Either way, December will finish much much warmer than average across the region which is as expected.

It was a case of missing the potential. This band came at the end of a significant multi-day event...lake effect snow warnings were allowed to expire that morning before the band got going. A surface trough dropped across the lake and stalled along the shoreline for several hours late in the afternoon and really focused the band.Looking back at the soundings from DTX that day there was good moisture and instability below about 8k feet upwind of the lake and likely better parameters downwind of the lake...I definitely didn't expect the band to form like that myself but in retrospect it probably could've been forecast somewhat better. Most of our good W-E bands in NE Ohio occur when a surface trough drops across the lake.

We'll see on the lows. It looks like Saturday's record warm min is also 47. It is a long time between sunset and midnight for sure this time of year, but with clouds, high dew points and southerly breezes I can't see much of a fall off Saturday or Sunday evenings. Saturday's record could probably be broken pretty easily if the warm air gets here quickly enough Friday evening and we're above 47 midnight Friday night. The one caveat for Sunday would be the cold front moving through before midnight, but the models have trended slower with the front recently it looks like. Ha, I believe the NWS office is actually a good distance from the new air traffic control tower...and I believe the NWS office may be moving to downtown at some point within the foreseeable future (although maybe not this year). I'd definitely be worried measuring snow so close to a building, but the alternative is having it all blow away I guess.

This is CLE's new location for measuring snow this winter. Here's some more info from the person who took the picture: "Well here is where the weather observers will be taking snowfall measurements. Photo was taken indoors and there is a large wall just left of the picture. This is facing south." He said last year they measured near the west end of an "open field". So we'll see if this makes a difference. Definitely have to think snow blowing off the building with a northerly wind would be a concern. This weekend looks very warm. Record highs and warm lows will be threatened. Sunday's record warm low of 47 could be obliterated...the 0z Euro has a low of 58 for Sunday...wow.

My friend works at the airport and got a picture and gave a description of where they'll be measuring snow this winter. I'll post it here at some point.

A few areas got 1-3", mainly inland in the primary Snowbelt...although there is a 2" report from Lorain County too. In general my first map worked very well, would've liked to actually see a 4" report to be happier with my upward bump. I'm hopeful that at some point within the next 40 days we'll be tracking something bigger than these 1-4" snow events. PUBLIC INFORMATION STATEMENT SPOTTER REPORTS NATIONAL WEATHER SERVICE CLEVELAND OH 1101 AM EST THU DEC 03 2015 THE FOLLOWING ARE UNOFFICIAL OBSERVATIONS TAKEN DURING THE PAST 25 HOURS FOR THE STORM THAT HAS BEEN AFFECTING OUR REGION. APPRECIATION IS EXTENDED TO HIGHWAY DEPARTMENTS...COOPERATIVE OBSERVERS...SKYWARN SPOTTERS AND MEDIA FOR THESE REPORTS. THIS SUMMARY IS ALSO AVAILABLE ON OUR HOME PAGE AT WEATHER.GOV/CLEVELAND **********************12 HOUR SNOWFALL********************** LOCATION 12 HOUR TIME/DATE COMMENTS SNOWFALL OF /INCHES/ MEASUREMENT OHIO ...ASHLAND COUNTY... ASHLAND 0.2 1032 AM 12/03 SNOW SPOTTER ...ASHTABULA COUNTY... JEFFERSON 2.0 1027 AM 12/03 SNOW SPOTTER GENEVA 0.7 1053 AM 12/03 SNOW SPOTTER 1 E ORWELL 0.5 1056 AM 12/03 SNOW SPOTTER ...CRAWFORD COUNTY... GALION T 1052 AM 12/03 SNOW SPOTTER ...CUYAHOGA COUNTY... BROADVIEW HTS 0.5 1025 AM 12/03 SNOW SPOTTER CLEVELAND HOPKINS AI 0.3 1058 AM 12/03 ASOS ...ERIE COUNTY... HURON T 1029 AM 12/03 SNOW SPOTTER ...GEAUGA COUNTY... MONTVILLE 3.2 934 AM 12/03 SNOW SPOTTER CHARDON 2N 3.0 1019 AM 12/03 SNOW SPOTTER CHARDON 2.5 1021 AM 12/03 SNOW SPOTTER SOUTH MADSION 2.0 1022 AM 12/03 SNOW SPOTTER ...HURON COUNTY... NEW LONDON 3NW 0.6 1031 AM 12/03 SNOW SPOTTER ...LAKE COUNTY... 4 SW KIRTLAND 1.4 1023 AM 12/03 SNOW SPOTTER MENTOR 0.7 1019 AM 12/03 SNOW SPOTTER PAINESVILLE 0.5 1055 AM 12/03 SNOW SPOTTER ...LORAIN COUNTY... KIPTON 0.5 1021 AM 12/03 SNOW SPOTTER ELYRIA 0.1 1022 AM 12/03 SNOW SPOTTER ...LUCAS COUNTY... TOLEDO EXPRESS AIRPO T 1059 AM 12/03 ASOS ...MEDINA COUNTY... BRUNSWICK 0.7 1030 AM 12/03 SNOW SPOTTER LODI 0.5 1053 AM 12/03 SNOW SPOTTER WADSWORTH 0.5 932 AM 12/03 TRAINED SPOTTER ...PORTAGE COUNTY... DIAMOND T 935 AM 12/03 SNOW SPOTTER ...RICHLAND COUNTY... MANSFIELD LAHM AIRPO T 1058 AM 12/03 ASOS ...SUMMIT COUNTY... AKRON CANTON AIRPORT 0.2 1057 AM 12/03 ASOS ...TRUMBULL COUNTY... YOUNGSTOWN WARREN AI 0.6 1059 AM 12/03 ASOS NEWTON FALLS 0.3 1054 AM 12/03 SNOW SPOTTER WARREN 0.2 1055 AM 12/03 SNOW SPOTTER ...WAYNE COUNTY... DOYLESTOWN 0.5 1032 AM 12/03 SNOW SPOTTER ...WOOD COUNTY... PERRYSBURG T 1028 AM 12/03 SNOW SPOTTER PENNSYLVANIA ...CRAWFORD COUNTY... MEADVILLE 5W 2.0 1033 AM 12/03 SNOW SPOTTER CANADOHTA LAKE 1.3 1018 AM 12/03 SNOW SPOTTER MEADVILLE 1.2 1030 AM 12/03 SNOW SPOTTER ...ERIE COUNTY... NORTHEAST 6SW 4.0 1031 AM 12/03 SNOW SPOTTER COLT STATION 3.5 1020 AM 12/03 SNOW SPOTTER CORRY 2.0 1027 AM 12/03 SNOW SPOTTER AMITY TWP 1.3 1020 AM 12/03 SNOW SPOTTER MILLCREEK TWP 1.2 933 AM 12/03 SNOW SPOTTER GIRARD 0.5 1028 AM 12/03 SNOW SPOTTER ERIE AIRPORT 0.4 1058 AM 12/03 ASOS **********************24 HOUR SNOWFALL********************** LOCATION 24 HOUR TIME/DATE COMMENTS SNOWFALL OF /INCHES/ MEASUREMENT OHIO ...ASHLAND COUNTY... 1 NNE SULLIVAN 0.9 700 AM 12/03 COCORAHS 1 WNW ASHLAND 0.2 600 AM 12/03 COCORAHS ...CUYAHOGA COUNTY... 2 NNW PARMA 0.2 800 AM 12/03 COCORAHS ...ERIE COUNTY... 5 NNE WAKEMAN 1.3 700 AM 12/03 COCORAHS N BERLIN HEIGHTS 1.0 700 AM 12/03 COCORAHS 2 NNE CASTALIA 0.5 700 AM 12/03 COCORAHS ...GEAUGA COUNTY... 1 SSE MONTVILLE 3.2 430 AM 12/03 COCORAHS 1 NE MIDDLEFIELD 0.5 800 AM 12/03 COCORAHS ...LAKE COUNTY... 3 SW WILLOUGHBY 0.4 700 AM 12/03 COCORAHS ...LORAIN COUNTY... 6 SW WELLINGTON 2.0 800 AM 12/03 COCORAHS SE ELYRIA 0.1 707 AM 12/03 COCORAHS ...MEDINA COUNTY... 5 WNW WADSWORTH 1.0 602 AM 12/03 COCORAHS 1 NE BRUNSWICK 0.7 700 AM 12/03 COCORAHS 8 ENE MEDINA 0.4 700 AM 12/03 COCORAHS ...OTTAWA COUNTY... 3 W PORT CLINTON 0.1 900 AM 12/03 COCORAHS ...PORTAGE COUNTY... 1 NNW MANTUA 0.5 700 AM 12/03 COCORAHS N HIRAM 0.4 700 AM 12/03 COCORAHS 2 SSW STREETSBORO 0.3 700 AM 12/03 COCORAHS 4 NE KENT 0.2 800 AM 12/03 COCORAHS ...TRUMBULL COUNTY... YOUNGSTOWN-WARREN RE 1.0 651 AM 12/03 ASOS PENNSYLVANIA ...CRAWFORD COUNTY... 1 NE CONNEAUT LAKE 1.5 700 AM 12/03 COCORAHS 3 WNW SPRINGBORO 0.6 615 AM 12/03 COCORAHS ...ERIE COUNTY... 6 SW ERIE 0.7 600 AM 12/03 COCORAHS 1 WNW NORTH EAST 0.5 800 AM 12/03 COCORAHS ***********************SNOW ON GROUND*********************** LOCATION SNOW TIME/DATE COMMENTS ON GROUND OF /INCHES/ MEASUREMENT OHIO ...ASHLAND COUNTY... ASHLAND 0.5 1032 AM 12/03 SNOW SPOTTER 1 NNE SULLIVAN 0.5 700 AM 12/03 COCORAHS ...ASHTABULA COUNTY... JEFFERSON 2.0 1027 AM 12/03 SNOW SPOTTER GENEVA 0.7 1053 AM 12/03 SNOW SPOTTER 1 E ORWELL 0.5 1056 AM 12/03 SNOW SPOTTER ...CUYAHOGA COUNTY... BROADVIEW HTS 0.5 1025 AM 12/03 SNOW SPOTTER 2 NNW PARMA T 800 AM 12/03 COCORAHS ...ERIE COUNTY... 5 NNE WAKEMAN 1.3 700 AM 12/03 COCORAHS N BERLIN HEIGHTS 0.5 700 AM 12/03 COCORAHS HURON T 1029 AM 12/03 SNOW SPOTTER ...GEAUGA COUNTY... 1 SSE MONTVILLE 3.0 430 AM 12/03 COCORAHS MONTVILLE 3.0 934 AM 12/03 SNOW SPOTTER SOUTH MADSION 2.0 1022 AM 12/03 SNOW SPOTTER CHARDON 2N 1.0 1019 AM 12/03 SNOW SPOTTER 1 NE MIDDLEFIELD 0.5 800 AM 12/03 COCORAHS ...HURON COUNTY... NEW LONDON 3NW 1.0 1031 AM 12/03 SNOW SPOTTER ...LAKE COUNTY... MENTOR 1.0 1019 AM 12/03 SNOW SPOTTER 4 SW KIRTLAND 1.0 1023 AM 12/03 SNOW SPOTTER PAINESVILLE T 1055 AM 12/03 SNOW SPOTTER ...LORAIN COUNTY... KIPTON T 1021 AM 12/03 SNOW SPOTTER ...MEDINA COUNTY... 5 WNW WADSWORTH 1.0 602 AM 12/03 COCORAHS WADSWORTH 0.5 932 AM 12/03 TRAINED SPOTTER 8 ENE MEDINA 0.4 700 AM 12/03 COCORAHS BRUNSWICK T 1030 AM 12/03 SNOW SPOTTER 1 NE BRUNSWICK T 700 AM 12/03 COCORAHS ...PORTAGE COUNTY... 1 NNW MANTUA 0.5 700 AM 12/03 COCORAHS N HIRAM 0.4 700 AM 12/03 COCORAHS 1 E RAVENNA T 750 AM 12/03 COCORAHS 2 SSW STREETSBORO T 700 AM 12/03 COCORAHS ...RICHLAND COUNTY... 1 NW LEXINGTON T 800 AM 12/03 COCORAHS ...SANDUSKY COUNTY... 2 ENE FREMONT T 500 AM 12/03 COCORAHS ...TRUMBULL COUNTY... YOUNGSTOWN WARREN AI 1.0 1059 AM 12/03 ASOS NEWTON FALLS T 1054 AM 12/03 SNOW SPOTTER ...WAYNE COUNTY... DOYLESTOWN 0.5 1032 AM 12/03 SNOW SPOTTER ...WOOD COUNTY... 2 WSW PERRYSBURG T 500 AM 12/03 COCORAHS PENNSYLVANIA ...CRAWFORD COUNTY... MEADVILLE 5W 2.0 1033 AM 12/03 SNOW SPOTTER 1 NE CONNEAUT LAKE 1.5 700 AM 12/03 COCORAHS CANADOHTA LAKE 1.0 1018 AM 12/03 SNOW SPOTTER MEADVILLE 1.0 1030 AM 12/03 SNOW SPOTTER 3 WNW SPRINGBORO 0.6 615 AM 12/03 COCORAHS ...ERIE COUNTY... NORTHEAST 6SW 4.0 1031 AM 12/03 SNOW SPOTTER COLT STATION 3.0 1020 AM 12/03 SNOW SPOTTER CORRY 2.0 1027 AM 12/03 SNOW SPOTTER MILLCREEK TWP 1.0 933 AM 12/03 SNOW SPOTTER AMITY TWP 1.0 1020 AM 12/03 SNOW SPOTTER 6 SW ERIE 0.7 600 AM 12/03 COCORAHS 1 WNW NORTH EAST 0.5 800 AM 12/03 COCORAHS GIRARD 0.5 1028 AM 12/03 SNOW SPOTTER ERIE AIRPORT T 1058 AM 12/03 ASOS $

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Definitely looks like you had to be higher up for this one. I see some light accums on the traffic cams in SW Lake and a little down 271 but less than an inch. Heaviest precip fell where it was too warm to accumulate well. We'll see what totals CLE gets soon...I wonder if that 3" Chardon report will make it into their PNS. By "light accumulations" I mean "a few patches of fading white on grassy surfaces"

I'll have to look again when I get off work but I'm liking the odds of someone in eastern Cuyahoga or Geauga getting something like 4". Models came in a bit cooler, temps and dew points are on schedule and the hi-res models seem to be liking that area for heavy snow early Thursday AM. Edit: I did bump up my map this afternoon before work. I don't see any reason to not ride with this at this point. Radar lighting up over lake, temps inland into the mid 30s, rain/snow falling already away from the lake where it's precipitating.

Although I’m not sure how much snow ultimately falls due to marginal temperatures, we’ve had a slow start to the LES season in NE Ohio, so I’m going to do a write up on this event. Aloft, a closed off upper level trough will move right over Ohio Wednesday night, with strong height falls, a good shot of PVA and deep moisture. The upper trough will also bring colder mid-level temperatures and a surge of colder air at the surface behind a secondary cold front that will move through early Wednesday evening, which will allow some lake induced instability to develop Wednesday night in combination with synoptic lift and deep moisture. As the upper trough moves overhead Wednesday evening, the models are in good agreement on an inverted trough in the low-mid levels developing across Lake Erie into extreme NE Ohio and into northern PA. The models have come into agreement on perhaps initially lifting this trough across the Cleveland metro early Wednesday evening, before lifting it northeast a tad over the primary Snowbelt and then swinging it southeast early Thursday morning as the upper low begins pulling away and winds turn more NNWrly. The area where this inverted trough “pivots” (somewhere over far NE Ohio or perhaps NW PA) will likely see the most prolonged period of moderate to heavy precip, and will likely see a good amount of QPF…the question will be how much of this falls as snow. There appears to be good potential for heavy precipitation where this inverted trough sets up Wednesday evening due not only to lake enhancement but also due to good synoptic moisture and non-lake effect related sources of lift. The low resolution NAM shows the convergence with the trough over Lake Erie and far NE OH/NW PA extending up above 700mb, with good vertical velocities showing up as a result. On its own, convergence this strong would likely be enough to get half decent precip to develop. In addition, positive vorticity advection in the mid-levels with the upper trough is also a source of lift. In addition to a good amount of lift from the trough moving over Lake Erie/far NE Ohio, the upper trough will provide for very deep ambient moisture…to around 500mb…so moisture will not be a limiting factor to this event. Although lake to 850mb and lake to 700mb temperature differentials won’t be extreme…13-15C for the lake to 850mb differential and 23-25C for the lake to 700mb differential…the upper trough moving directly overhead will bring inversion heights way up, to near 15k feet. So although lake induced instability isn’t “extreme,” there’s lake induced CAPE and deep moisture to 12-15k feet or slightly higher from Wednesday evening through early Thursday. 500mb temperatures are progged to get to around -32C Wednesday night, which gives lake to 500mb temperature differentials of 40-42C off of the central and eastern basin. This is around the threshold for thunder, so although there won’t be a lot of lake induced CAPE, the deep layer of moisture/instability and strong lift from the trough through a fairly deep layer of the atmosphere may be enough for some lightning strikes over and near the lake at times, mainly during the first half of Wednesday night. At this point I’m fairly convinced that moderate to heavy precip will develop Wednesday evening and persist for several hours Wednesday night…possibly over the Cleveland metro early on before shifting into the primary Snowbelt for a good chunk of time, before swinging southeast and then weakening early Thursday. The main questions now become if temperatures will cool quickly enough to support accumulating snow, and if this happens, where will the heaviest precipitation and possible accumulations be? One factor that may be important will be wet bulb temps…especially south of the band…as WSW winds into the band could advect in this cooler/drier air and allow wet bulb cooling to occur under the band along with dynamic cooling from lift within the band and perhaps precipitation drag of cooler air down to the lower levels. The NAM at 10PM Wednesday has wet bulb temperatures near 40F under the band and above 35F across much of northern OH…while the GFS on the right is several degrees cooler. The difference appears to be due to the NAM showing dew points in the mid 30s persisting inland until much later Wednesday night, while the GFS cools dew points to near or below 30F inland from the band after midnight. Dew points to our west are in the upper 20s/lower 30s, so I am inclined to believe the lower dew points inland, which would support wet bulb temperatures being a bit cooler. The wet bulb temps appear to cool enough for a change to snow to start occurring after 10PM. The NMM has temperatures under the band (this model has it across Lorain and Cuyahoga Counties initially) cooling to 33-36F by 10PM, with that cooling continuing as the band swings northeast over the next few hours into the primary Snowbelt after midnight. Given the potential for good dynamical cooling under the band and wet bulb cooling from cooler/drier air inland trying to get drawn into the band, a scenario like this seems quite possible…although the model does never get temperatures below freezing under the band. The NAM shows 925mb temperatures starting to fall below freezing by 10PM Wednesday…and getting below freezing in much of the NE OH Snowbelt by 1AM Thursday…by 4AM Thursday it also gets 925mb temps below freezing in NW PA. Based on when wet bulb temperatures inland get below freezing and when 925mb temps are progged to fall below freezing, my guess is that locations inland from the lake, especially in the higher terrain in Geauga County and NW PA, will start changing to snow by 10PM Wednesday and become mostly snow by around midnight. The precipitation should start as rain possibly mixed with graupel initially, as low level temps will definitely be too warm for snow initially. The hi-res models are in decent agreement on 0.50-0.75”+ of QPF where the band stalls for a few hours late tomorrow evening into the wee hours of Thursday morning. The Euro and low-res NAM also even have over half an inch of QPF, and the GFS has 0.25-0.50” of it. At this point, for placement of the lake enhanced band, the NAM, Euro, GFS and ARW (along with most of BUF’s WRFs) develop it initially over the Cleveland metro before quickly moving it northeast into Lake, northern Geauga, Ashtabula and parts of Erie/Crawford Counties, while the NMM and hi-res Canadian are a bit farther south. The band placement will be mainly driven by where the synoptic inverted trough develops and less by lake effect processes, however with WSW winds south of the band and a warm lake possibly trying to focus the surface trough a little farther northeast, I’m going to lean towards the north camp. The models do swing the band SE early Thursday morning, which could bring a period of decent precip in much farther west, but it would be brief. Lake effect conditions remain OK into Thursday morning, but the synoptic support will be over, and winds will turn onshore which will push warmer air over the lake farther inland, so I doubt there are any real accums in the NNW flow lake effect Thursday morning once the trough moves southeast. Accumulations with the trough are ultimately tough…we’ll definitely have a good amount of QPF to play with, and given there are mesoscale processes driving the precipitation including lake enhancement, I have to think the hi-res models with the higher QPF are more on the mark. The question, how much falls as snow and how well does it accumulate? I don’t expect any accumulations before 10PM…but should see the precip change to mainly snow (especially inland) between 10PM and midnight, with accumulations likely starting in the higher terrain by midnight. This gives a few hours and a quarter inch or so of QPF of potential accumulating snow in the primary Snowbelt before the trough swings southeast and takes the band with it. This could give 2-3” in the higher terrain in northern Geauga County and southern Erie/northern Crawford Counties. If the changeover occurs any quicker, or the models are a little too quick in shifting the trough southeast, someone could get a little more. I could see 1-2” in the rest of the primary Snowbelt excluding the lakeshore, with little to none along the lakeshore, as surface temps should stay in the 35-40 range. Maybe a heavier burst deposits a dusting along the shore, but I struggle to see any more playing out. There could be a brief burst of snow farther west later at night, but with marginal surface temps and a short duration of decent snows, although some grassy/car top type dusting are possible, I don’t expect more than an inch outside of the primary Snowbelt right now. Here's my fairly low confidence map:

Interesting looking scenario Wednesday evening up there...and even here I think I could see a legitimate snow shower Wednesday night... The upper low is progged to move right over Lake Erie Wednesday night, with good moisture and marginally cold enough temperatures for accumulating snow (especially inland from the lake). The NAM was slightly more interesting than the GFS as it had a very sharp low-mid level trough/wind shift dropping south off of Lake Erie Wednesday night, which would provide for decent synoptic lift (along with decent vorticity advection with the upper low moving overhead) to go along with some instability off the lake, and probably result in a period of moderate to briefly heavy precipitation downwind of the lake. The GFS has the trough/wind shift dropping in a little farther northeast, so although there'd still probably be a period of enhanced precip, it would be more focused on extreme NE Ohio and NW PA (as opposed to the NAM which would drop the heavier precip right into Cleveland east into Geauga/Portage Counties and maybe even down towards YNG). Although the lake to 850 and lake to 700mb temp differentials aren't extreme, both models have good moisture up to about 15k feet as the trough tries dropping south Wednesday night with lake to 500mb temp differentials pushing 40C+...which would likely combine with the synoptic lift from the trough to produce moderate to heavy precip. 850mb temps are progged to be in the neighborhood of -5 to -7C, with 925mb temps of around -1 to -2C, which is marginal...however, if the setup works out, I'd have to think that the precip would dynamically cool things enough to force the precip over to all snow with accumulations not too far inland. FWIW, the Euro is closer to the NAM and brings the heavier precip right through Cleveland. Although the window looks brief...with the potential for very good lift from the trough combined with a deep layer of moisture and instability...I could see some fairly quick accumulations playing out and lightning wouldn't shock me. My first guess is 1-3" inland from the lake and maybe sloppy dustings near the lake wherever the trough drops in...be it near Cleveland or farther NE towards Ashtabula or NW PA...but this could be something sneaky to watch and locally more snow wouldn't shock me. I want to see the NAM and Euro hold for another run or two before getting too excited about this possibly occurring in the Cleveland metro.

Another lack luster PNS from CLE. I feel like I have to wait for you or DTA to post to know how much snow falls in western Geauga County. No reports from eastern Cuyahoga or western Geauga. It's been like that for a while too and makes no sense, especially since the 271 corridor is very populated.

I'd have to imagine a few spots in that area east into parts of Geauga squeaked in advisory amounts or at least got close, but outside of the band this morning most areas are struggling to hit the low end of predicted amounts. The hi-res models still insist on one more burst tonight over the heart of the Snowbelt...maybe that can push a few areas up another inch or two. Since it was the first accumulating snow of the season and a lot of the snow fell in a fairly short time I'm ok with the advisory this go around even if it's marginal (well go figure I was clambering for them to issue one) It definitely looks like the first inch at CLE has a good chance at having to wait till December at some point.

It looks like it's snowing very hard downtown right now on traffic cams, but the band is slowly moving.

The winds look like they're still taking on a bit more of a northerly component. We'll see if that disrupts the band or if it just shifts south a little but keeps going. Edit: and there's the advisory for Cuyahoga

CLE needs an advisory for Cuyahoga right now. Really inconsistent handling of this storm. Went watch for Ashtabula and NW PA...then they just go advisory for Erie County...then expand the advisories 5 hours later...and now the heaviest snow may be falling outside of the advisory area. Welcome to lake effect snow I guess.

It is using the full fetch...and you can see it better on satellite...but because of the dry air it doesn't start showing up on radar for a while.

The storm pulling out faster and letting dry air in really killed this one. We have the long fetch and good instability but yeah, dry air is often killer. The winds don't look too strong by late tonight though but we'll see.

Ehh CLE is going to punt this another shift. Leaving the watch as is for Ashtabula and NW PA

Agree. Even with my forecast as is (assuming it doesn't over-perform), I'd still issue advisories for Lake, Geauga and Ashtabula...and at least consider going for one for Cuyahoga too...especially since it's the first accumulating snow of the season. We should find out what CLE's going to do soon.

Wow! Dew points in the 10s must be helping the snow make it to the ground