Northern Ohio Obs/Discussion Part 2

[NEOH]

Looking at their forecast graphics, they have temps quickly rising into the lower 50's tonight, but have lower 40's right about now (which is several degrees too cool) which is where that low comes from. Cincinnati is pushing 60, so I wonder if we can get like 57 or 58 as a pre-dawn high tomorrow.

 

I'm stuck at 47 degrees. Temps will probably surge prior to the frontal passage. The bad thing is that temps have been in the mid-30's all day in western OH. That's the place that warm temps and heavy precip would have been helpful for LES purposes... but not the case unfortunately. West of Sandusky seems to be the line between warm/cold.

[OHweather]

I'm stuck at 47 degrees. Temps will probably surge prior to the frontal passage. The bad thing is that temps have been in the mid-30's all day in western OH. That's the place that warm temps and heavy precip would have been helpful for LES purposes... but not the case unfortunately. West of Sandusky seems to be the line between warm/cold.

I'd imagine they got enough rain and will see enough wind to disperse the ice starting to form, although a warmer push of air would've been nice there too.

[Trent]

BKL surging with downsloping. Up to 55 there.

There's a tight temp gradient between Toledo and Sandusky. I noticed that some places around Sandusky rose from the mid 30s to low 50s in a matter of minutes in the past hour when the warm front pushed through and winds shifted. Hopefully that continues to push a bit more towards Toledo overnight.

[NEOH]

Temp spiked up to 56 IMBY last night. Impressive warmth. Almost an inch or rain as well. Temps and rain have even softened the frozen ground. GFS has come around to the NAM for a more westerly flow tonight/tomorrow it seems. 280 or so looks to be the direction. Hopefully we can maintain open water for the LES following the clipper.

[OHweather]

Looking at the 12z NAM and recent RAP runs, they now bring the winds around to a solid WNW direction tonight. Granted, moisture depth and inversion heights are very marginal. The 0z ARW and NMM again spit out a quarter to half inch of QPF under any banding across the Snowbelt, but that may be a bit high. There could be an ok burst this evening with the wrap around snow showers that drops up to an inch, and then we see where any bands set up. I could see locations like 422 doing OK if the latest NAM and RAP are right about the winds. Moisture depth and inversion heights are pretty marginal (inversions around 7k feet and moisture up to 4-5k feet) so you'd have to get under a band for a little while to see more than an inch or two.

[dta1984]

Should be an exciting week! With the clipper looking to slide south, hopefully we cash in on good le.

[NEOH]

Looking at the 12z NAM and recent RAP runs, they now bring the winds around to a solid WNW direction tonight. Granted, moisture depth and inversion heights are very marginal. The 0z ARW and NMM again spit out a quarter to half inch of QPF under any banding across the Snowbelt, but that may be a bit high. There could be an ok burst this evening with the wrap around snow showers that drops up to an inch, and then we see where any bands set up. I could see locations like 422 doing OK if the latest NAM and RAP are right about the winds. Moisture depth and inversion heights are pretty marginal (inversions around 7k feet and moisture up to 4-5k feet) so you'd have to get under a band for a little while to see more than an inch or two.

 

Good to hear. Anything that falls before the clipper is a bonus. Although the clipper is looking more and more like a 30 corridor on south event. Radar looks good to our west so hopefully we can all wake up to an inch or two or snow tomorrow.

[OHweather]

Good to hear. Anything that falls before the clipper is a bonus. Although the clipper is looking more and more like a 30 corridor on south event. Radar looks good to our west so hopefully we can all wake up to an inch or two or snow tomorrow.

CLE ended up issuing an advisory for Lake, Geauga and Ashtabula into NW PA for tonight into tomorrow, so we'll see. There will be a little shortwave that goes by tonight which may help a half decent band develop by dawn tomorrow and persist for a few hours, possibly as far south as 422, before it starts gradually shifting up the lakeshore. Should be the fluffy snow so we'll see if a band can actually form this go around or not. Moisture depth after this evening is iffy at only 5-6k feet, with an inversion at 6-8k feet and 300-500J/KG of lake induced CAPE, so it will probably take an organized band that doesn't move too much to get a few inches. That looks possible tomorrow morning behind the shortwave, so we'll see.

[Chinook]

What do you guys think for the LES potential on Jan. 7th? I see 850 and 700mb temps pretty darn cold. 700mb temps down to -34C over the lake, with a 30kt NW wind from the surface to 700mb. I wonder if snow bands will organize to make for a big snow event for NE Ohio. On the other hand, I wonder if this is -too- cold and dry. Then again "too dry" seems a little dumb seeing as how the RH values aren't too bad on the GFS.

[OHweather]

What do you guys think for the LES potential on Jan. 7th? I see 850 and 700mb temps pretty darn cold. 700mb temps down to -34C over the lake, with a 30kt NW wind from the surface to 700mb. I wonder if snow bands will organize to make for a big snow event for NE Ohio. On the other hand, I wonder if this is -too- cold and dry. Then again "too dry" seems a little dumb seeing as how the RH values aren't too bad on the GFS.

The NAM appears to show saturation and decent omega in the *small* DGZ on Wednesday, so I don't think it'll be too cold. Ratios might come down to more like 15-20:1 due to the limited size of the DGZ by Wednesday afternoon, but I figure it won't be so cold that all we see are needles falling.

 

The interesting potential IMO is a potentially really nice squall along the arctic front around daybreak Wednesday. The NAM shows an extremely nice cross-hair signature (omegas better than -25 in the DGZ) as the front pushes south off the lake early Wednesday, could be a period of white-out conditions with that.

 

We should all be getting light wrap around snow soon, will be nice to see.

[dta1984]

Temp dropped to 32 in a hurry. Mod snow right now

[dta1984]

Nasty outside. Mod snow and very windy.

[OHweather]

About half an inch here, roads are pretty icy. Lake effect may take some time to organize.

[dta1984]

Been snowing pretty good this morning. Nice band set up out to the west side. Hard to measure with the wind, but I'd guess 2" unofficially.

[NEOH]

Been snowing pretty good this morning. Nice band set up out to the west side. Hard to measure with the wind, but I'd guess 2" unofficially.

 

2" seems about right. Nice band is starting to take shape. Looks like it will be sliding just north of us though.

[dta1984]

2" seems about right. Nice band is starting to take shape. Looks like it will be sliding just north of us though.

Ya we look to be on the southern edge right now. Hopefully we can hang on.

I'm surprised cuy isn't under an advisory.

The wed- Thurs event looks interesting. Hopefully we can hold off or minimize any ice forming ...

[NEOH]

Ya we look to be on the southern edge right now. Hopefully we can hang on.

I'm surprised cuy isn't under an advisory.

The wed- Thurs event looks interesting. Hopefully we can hold off or minimize any ice forming ...

 

Yeah, not sure why NE Cuyahoga is left out... CLE seems to be doing that lately.

 

I'm pretty sure the western basin will be mostly iced over by Wednesday considering the cold temps. Lots of ice out west by Toledo...

[OHweather]

There wasn't any ice on that camera yesterday morning, too bad it's already icing again. The winds will shift around with the clipper going by, so hopefully that keeps the ice from forming solid until at least Wednesday night.

[dta1984]

There wasn't any ice on that camera yesterday morning, too bad it's already icing again. The winds will shift around with the clipper going by, so hopefully that keeps the ice from forming solid until at least Wednesday night.

I hope so. Weds was looking like the best setup we have had in a while.

[NEOH]

There wasn't any ice on that camera yesterday morning, too bad it's already icing again. The winds will shift around with the clipper going by, so hopefully that keeps the ice from forming solid until at least Wednesday night.

 

The good news is that we won't have a calm night... otherwise there would be a solid freeze up. Drove past a small lake today and noticed there was no ice... yet a large body of water had no problem developing ice quickly. The flow on Wednesday comes around to 320-310 it appears which takes most of the western basin out of play anyways. I'm sure there will be significant ice coverage from the islands back west.

 

Looks like snow with the clipper will be limited to 2-3" at the best.

[dta1984]

That sounds good, hopefully still a good event. Cle does seem optimistic.

I tried measuring and got around 2.5". Alot of wind whipped areas and drifting make it tough.

[Trent]

It'll be interesting to see if Wednesday unfolds with several small bands, a single band, or a general blob of snow.

Many times with a NW flow, the orographic lift really sets off the snow along and south of 480. However, there also tends to be one of those narrow bands that develops through Lorain County down to around Strongsville and then Northern Medina through Richfield and Northern Summit. Similarly another tends to form through Lake County and into Geauga.

I've seen these situations in the past where the bands don't move much and if you're under them you do great, but if you're between bands, you might escape the event without much.

There'll probably be a lot of now casting on Wednesday.

It's unfortunate the clipper has trended less impressive run after run, that would have made a great base.

[NEOH]

Reducing my call from the clipper to 1-2" at most. We will have to rely on the lake for our snows. I overly obsess about ice cover... but I hope the ice doesn't ruin the LES event on Wednesday.

[NEOH]

Just noticed CLE's updated snowfall map. Pretty hefty totals by Wednesday evening.

 

 

 

[Trent]

Wow. They definitely aren't going conservative with totals even when you factor in 2" of clipper snows overnight.

We're still a good 30 hours out, so lots of time for fine tuning the parameters.

I'm sure lake effect watches will go out soon

[Polar Vortex 2014]

Just noticed CLE's updated snowfall map. Pretty hefty totals by Wednesday evening.

 

Looks like the snow hits an impenetrable wall right at the edge of CLE and PBZ's CWAs.

[dta1984]

Lake effect snow watch for geauga. Totals over 8" possible. Also noticed the yellow area got moved a little further north since that map was posted.

[NEOH]

Looks like the snow hits an impenetrable wall right at the edge of CLE and PBZ's CWAs.

It has been in the works for years... Nearing completion as per the map.

[Trent]

CLE's snow map for hours 36-42 looks similar to what I mentioned before - a far east and far west side band. CLE also mentions the Huron connection in their discussion below. It seems that whenever a Huron connection develops, it's harder for this band to make it any further west than Ashtabula County. Then you tend to get that "secondary" smaller band just far away from the primary band that develops from Lorain southeastward. In between the two, you really miss out on the good stuff. I'm hoping that doesn't play out like that with this event as it misses most. 

 

HIGHER RESOLUTION MODELS ARE INDICATING A DOMINANT LAKE HURON BAND

EXTENDING ACROSS LAKE ERIE INTO NE OHIO. EXACT PLACEMENT IS HARD TO
DETERMINE AT THIS TIME ALTHOUGH ASHTABULA COUNTIES LOOKS LIKE THE
MAIN AREA. AREAS OUTSIDE OF THIS BAND MAY ONLY SEE ADVISORY LEVEL
SNOWS.

 

[OHweather]

A deep upper level trough will move across the Great Lakes Tuesday into Wednesday and allow very cold air to spill into Ohio. An arctic front will drop south across Lake Erie and northern Ohio between 2AM and 8AM Wednesday, with a northwest flow setting up behind it. Ahead of the front, a strong band will likely form along the eastern lakeshore and then swing south with the front. Behind the front, questions about drier air and a short fetch due to a NW flow make the forecast tough, despite extreme lake induced instability and very high inversions.

 

 

Ahead of the front, the hi-res models suggest strong convergence along the Lake Erie shoreline, with the winds trying to back to the SW over land while they become west and eventually WNW over Lake Erie. This seems like good support for a decent single band to form along the eastern lakeshore, and the NMM and ARW both show this by 1AM Wednesday:

 

 

BUFKIT forecast soundings by this point indicate moderate lake induced CAPE with equilibrium levels near 8k feet and rising, with moisture depth to 6-7k feet. These parameters are all marginal to good, and with such strong convergence evident on the mesoscale models along the eastern lakeshore I’d expect a band with moderate to heavy snow to be developing quickly by this point if it doesn’t develop even a few hours sooner:

 

 

The surface winds have a good southerly component, however with decent WNW winds in the boundary layer mixing to the surface over the lake, I’d imagine the band would be a few or several miles inland across Lake and Ashtabula Counties. There is good moisture and instability in the DGZ, so I’d expect very high snow ratios on the order of 20-30:1 in any band in this timeframe, so snow rates of 1-2” per hour seem like a good bet under any banding in Lake and northern Ashtabula Counties between midnight and 4AM Wednesday.

 

 

By 4AM Wednesday, the front is approaching the lakeshore but still hasn’t pushed inland yet per the 0z NAM, GFS and Euro, so I’d expect any band to still be close to the lakeshore…although it may begin budging south. Also, note the decent convergence as far west as Toledo, suggest a burst of snow could occur across all of northern Ohio as this front drops south just before dawn on Wednesday. The convergence across Lake and Ashtabula Counties into NW PA is extremely strong, and heavy snow rates are very likely in this timeframe.

 

 

By 7AM Wednesday, the models all show the front south of Cleveland and pushing through the Snowbelt, likely with a band of heavy snow with it. By this point, lake induced instability will be extreme (800-1000 J/KG of CAPE) with equilibrium levels rising to 10-12k feet. In addition, the NAM shows very strong omega along the front (CLE briefly has -30 ub/sec!!). Any band along the front could produce very heavy snow rates, although the band will be moving so the snow may not add up a ton:

 

 

Behind the front, instability remains extreme and equilibrium heights will remain in the 10-12k foot range until mid to late Wednesday afternoon. However, the fetch will become shorter and some low-level dry air may work in, limiting additional snowfall behind the front.

 

The winds immediately behind the front (see the BUFKIT forecast sounding for CLE above) will be very well aligned out of the WNW for a couple of hours, so I suspect some convergence and half decent snows will hang on for a couple of hours behind the front a bit inland from the lake…mainly across parts of Lorain, southern Cuyahoga, Medina, northern Summit, southern Geauga, Portage into Trumbull and possibly Mahoning. These areas could see another couple inches right behind the front by mid to late Wednesday morning.

 

By later Wednesday morning and into Wednesday afternoon, the flow will be true NW (one of the shortest fetches across Lake Erie for northern Ohio), and the models show some dry low-level air working into parts of Michigan from Canada. Although the air over Lake Erie will be extremely unstable with high inversions, I’m worried about this dry air. NAM forecast soundings for CLE suggest it may be hard to maintain a deck of lake effect clouds at times:

 

 

The winds are very well aligned, the layer of instability is deep and the amount of instability is very impressive for a lake effect situation. However, with a short fetch and a good 25-35 knot flow in the boundary layer I have some concerns. This may be where upstream lake connections come into play:

 

 

The NAM shows a couple of things that concern me…first of all, it shows cold and very dry air (dew points below 0 into lower MI, and -20 to -30F dew points in the core of the colder air) working across the narrow and partially frozen portions of Lakes Michigan/Huron and working towards central Lake Erie late Wednesday morning into Wednesday afternoon. This would potentially limit lake effect off of Lake Erie given the short fetch. In addition, this cold/dry air pushes the Lake Michigan connection well west of Cleveland. It is very typical to get a Lake MI connection in a NW flow and that is often why there is a band on the west side in a NW flow. You can tell where the connection is by following the convergence in the wind barbs. Between the two connections close to NE Ohio, the winds at the surface are somewhat divergent. This would also limit how organized any lake effect between the two connections is.

 

Because of this, it would not surprise me at all if by late Wednesday morning after the front passes well south and the winds become true NW that the lake effect across the Cleveland metro and also Lake and Geauga Counties becomes very weak/disorganized for a few or even several hours, with perhaps just light accumulations in this timeframe in the higher terrain. There could be heavy snow in eastern Ashtabula County into NW PA under the Lake Huron connection and perhaps decent light to moderate snow in the Lake MI connection well west of Cleveland. Snow ratios during this time frame might not be great either due to the drier air causing the ceilings to climb above the DGZ for a few hours Wednesday afternoon.

 

The NMM and ARW also show the cold/very dry air trying to work its way down towards Lake Erie early Wednesday afternoon:

 

 

Note how they both show one band west of Cleveland (one model shows it stronger than the other) and the Lake Huron band well east of Cleveland at the same time:

 

 

By Wednesday evening, the winds will begin backing to a more WNW and eventually W direction, which will lengthen the fetch over Lake Erie and perhaps allow some upstream conditioning from Lake Michigan and increase moisture some:

 

 

By this point, there will still be decent instability and pretty high equilibrium levels, and convergence will increase some along the central lakeshore and into the Snowbelt as high pressure moves in, so there will probably be an increase in snow Wednesday evening into Wednesday night across northern Lorain, Cuyahoga, Lake, Geauga, Ashtabula, Trumbull and possibly northern Summit/Portage that drops another 1 to locally 4” of what by that point should again be high ratio snow:

 

 

By 3-4AM the winds go pretty WSW which should confine things to the lakeshore by that point and effectively end the event for most of us…

 

So, how did I figure accums?

 

I figured 4-8” Tuesday night in Lake and northern Ashtabula Counties due to the band I expect to develop there…and then 2-3” across Cuyahoga, northern Medina, northern Summit, Geauga, southern Ashtabula and northern Trumbull as the arctic front drops south early Wednesday, with possibly another inch or two immediately behind the front across parts of Lorain, southern Cuyahoga, northern Medina, northern Summit, southern Geauga, northern Portage into parts of Trumbull, which pushes those areas to 3-5” by mid to late Wednesday morning. The arctic front could produce a quick inch or so everywhere else across north-central and NE Ohio outside of these areas. After the arctic front, I figured another 2-4” Wednesday afternoon across eastern Ashtabula County due to getting fringed by a potentially very heavy Lake Huron band…and perhaps another 1-3” across parts of inland Lorain, eastern Huron County into parts of western/southern Medina and maybe even the higher elevations in northern Ashland Counties due to the Lake MI connection there…with maybe another inch in the higher terrain in the primary and secondary Snowbelts. I think figured another 1-4” from Cuyahoga east Wednesday evening into the overnight with the last flareup I expect.

 

This pushes most of Lake and Ashtabula up to 6-12”, with perhaps a little more in eastern Ashtabula if they do get into the Huron connection. This gives a wide 4-8” area in the rest of the primary Snowbelt and surrounding areas. I drew 3-6” amounts well west to account for the possible Lake MI connection in that area. I didn’t feel comfortable with leaving the higher terrain in SW Cuyahoga and northern Medina in just 3-6” so I added a small 4-8” area there as well. Due to favorable orographic lift in northern Geauga I figured they could squeeze out a little more in every phase of the event so I also drew 6-12” in there. Although I didn’t draw it in on this map, I expect 1-2 feet across a good portion of Erie and Crawford Counties PA as they should also get in on the band Tuesday night ahead of the front and also the Lake Huron connection for several hours on Wednesday.

 

Map: