Northern Ohio Obs/Discussion Part 2

[OHweather]

As you guys know, the Cleveland NWS seems to be averse (being nice here) to issuing winter weather warnings.  I remember when the March 2008 snowstorm was approaching/occurring, all of Ohio was under a blizzard warning except for the Cleveland CWA which stuck to winter storm warnings.

 

...Funny how northern IN and western NY are under a winter weather advisory, winter storm warning respectively.  For Cleveland, only a wind chill warning. Surprised they issued a warning as it would be in keeping with their style to issue just a wind chill advisory.

 

 I'm really puzzled as to why CLE is always lowballing winter events (exception being the 2012 Boxing Day storm when CLE issued a blizzard warning...I was shocked at that.).

They actually have 5"+ as far west as KCLE and 8"+ for central Geauga eastward. I think their amounts are often ball park or even too high, but they have been very conservative with issuing winter headlines, especially this winter. I'm sure they have their reasons, but I really think this needs an advisory or even warning for the reasons I laid out above. Their snowfall amounts would at least suggest an advisory if not warning based on the blowing snow. I'm sure they'll issue something later tonight or tomorrow.

 

 

http://www.erh.noaa.gov/btv/gis/images/CLE_Snow.png

[LakeEffectOH]

They actually have 5"+ as far west as KCLE and 8"+ for central Geauga eastward. I think their amounts are often ball park or even too high, but they have been very conservative with issuing winter headlines, especially this winter. I'm sure they have their reasons, but I really think this needs an advisory or even warning for the reasons I laid out above. Their snowfall amounts would at least suggest an advisory if not warning based on the blowing snow. I'm sure they'll issue something later tonight or tomorrow.

 

 

Thanks for the update!  Yeah, I bet they will have to force themselves to issue an advisory.  They had no mention of snow/blowing snow in their latest Haz Wx Outlook. You would they would have mentioned something.

[NEOH]

Just saw that Buf has warnings for 6-12". Wasn't even expecting snow amounts so high, and so close to our area. Precip amounts don't vary that much between wny and northeast Ohio. Clearly not much collaboration between offices. We'll see what happens but if Buf is optimistic I can only think that CLe will be wrong in not issuing advisories.

[OHweather]

I'm working on a write up for my blog and will post it here when I get done in an hour or two. In the meantime, here's my map. Am concerned about locally higher amounts, but with ratios getting really low by later tomorrow afternoon I'm not sure the higher terrain can squeeze out more than 2-3" of very fine flake lake effect.

 

[dta1984]

Snow has started. I agree, definitely surprised there is not a warning or advisory out. I imagine roads will be a mess tomorrow and lots of traffic with valentines dinners,movies etc. I did see the wind chill watch includes snow amounts ....thought that was odd.

Good map ohweather. I like these events that have potential for surprises. Maybe the lake will contribute more, better ratios etc.

[OHweather]

I was trying to be "sociable" while typing this (it is Friday night after all) so it took a while haha

 

 

A tall +PNA ridge extending almost to the North Pole is helping facilitate a cross polar flow Friday afternoon, which is allowing frigid air to pour south towards the Great Lakes straight from the Arctic. A lobe of the polar vortex (currently over western Hudson Bay) will drop south through the Great Lakes on Saturday, causing a surface low pressure pictured over Lake Superior above to move southeast and intensify across the lower Lakes. This will cause some light to moderate synoptic snow along and ahead of a cold front that will drop across northern Ohio Saturday morning, and the deep arctic airmass behind the front will help cause some lake effect snow across northern Ohio. Ice on Lake Erie and upstream lake moisture will be critical to the lake effect forecast.

 

 

For the remainder of tonight and into Saturday morning, a nice shot of upper level divergence in the left-front quadrant of an upper level jet streak combined with some half decent warm air advection on the nose of a strong mid-level jet will cause light snow across northern Ohio. There could be an inch or so of snow by 7AM Saturday as most models spit out around 0.1” or a little less of liquid precip. Ratios tonight should be 12-15:1 with most of the modest low to mid level lift focused in the DGZ.

 

As we head into Saturday, low level convergence will really increase along and immediately ahead of the arctic frontal boundary, and falling mid-level temperatures will result in steepening low to mid level lapse rates and some surface based instability. This will lead to the snow becoming a little more snow showery after sunrise on Saturday, but the snow intensity will also increase. This will all culminate in a brief period (an hour or so) of blinding snow squalls along the arctic front late Saturday morning near Lake Erie and around noon or so farther inland. A look at synoptic model plots and forecast soundings in BUFKIT all suggest a very impressive snow squall potential along the arctic front:

 

 

There will be a very impressive shot of positive vorticity advection early Saturday afternoon across northern Ohio (and much of the state really). This is a source of lift and can also help raise equilibrium levels and increase instability.

 

 

In addition, low level frontogenesis and convergence will be very strong along the arctic front (both sources of lift). Note how at 850mb, there is a very sharp temperature gradient, and also note the sharp and sudden shift in wind direction and increase in wind speeds along and behind the arctic front. These are both sources of convergence and lift that can help an intense snow squall develop.

 

 

As alluded to above, the frontogenesis values are fairly strong in the low levels along the arctic front as it drops across northern Ohio late Saturday morning and early afternoon. The layer of deep moisture and steep lapse rates along the front on forecast soundings is impressive due to falling mid-level temps and large scale lift acting to steepen lapse rates and raise inversion levels:

 

 

Although the model does show a weak inversion limiting the model equilibrium level, the steep lapse rates and good moisture extend well above 10k feet in the atmosphere. If there is enough open water on Lake Erie to modify the airmass at all, equilibrium levels easily climb above 10k feet. This all suggests a heavy burst of snow.

 

 

The snow along the arctic front will not only be intense, it will also be very high ratio, with large dendrites likely. Note how the omega (vertical velocity) in the red lines is very strong in the dendrite growth zone (the purple and yellow contours). This suggests that snowflakes will grow very effectively in any snow squalls along the arctic front. With strong omega up to about 17k feet, a flash or two of lightning in any squalls along the front wouldn’t shock me.

 

Although the snow squalls along the arctic front will be short lived, totals by early afternoon from a combination of the light snow tonight into early Saturday, and the snow showers/likely squalls ahead of and along the arctic front will likely be 2-4”. The high ratio nature of the snow up through this point will improve the likelihood of these totals being realized.

 

Forecast soundings show 30-40 knot winds along and behind the arctic front in the boundary layer, really just above the ground…cold air advection should help a large portion of that mix down in gusts, causing 30-40MPH wind gusts along/behind the arctic front…strongest near Lake Erie. Due to the high ratio nature of the snow, it will easily blow around. Blowing snow along/behind the arctic front will undoubtedly cause visibility issues and road condition issues.

 

 

Although there were some cirrus clouds on Friday, we got a good MODIS shot of Lake Erie. There is a large crack in the ice east of the Lake Erie islands towards Lorain (very common), and also along the northern lakeshore. These cracks appear to be slushy, but could open up some with breezy  SW winds late Friday night into early Saturday and strong NWrly winds Saturday afternoon behind the arctic front. There are a few smaller cracks farther east, including a pencil thin but long from all the way up the central and eastern lakeshore that may open some if the southwesterly winds into early Saturday enough.

 

So, not a lot of moisture to be picked up off of Lake Erie, but definitely some.

 

 

Immediately behind the arctic front, instability may briefly decrease for a time as surface temperatures crash a little quicker than the mid-level temps (above)…however, the mid-level temps will quickly recover. There’s still a fairly deep layer of steep lapse rates (that gets deeper again by mid to late afternoon) behind the front and high RH air to above 10K feet, so orographic lift could help ring out snow showers starting very quickly behind the front.

 

 

By later afternoon, a very deep layer of steep lapse rates will return and good moisture will remain to above 5k feet. Winds will become very well aligned out of the northwest. This may help any lake effect/orographic lift snow showers increase late Saturday afternoon after perhaps a brief lull behind the front. Snow growth will really diminish by this point as the dendrite growth zone is confined to near the ground (much of the lift is just above the ground). This suggests that even as lake effect snow/orgraphic lift snow increases again later Saturday afternoon that it may not pile up as quickly.

 

 

The increase in instability later Saturday afternoon will correspond to the vort-max (500mb vorticity on right) moving over Lake Erie and also an increase in mid-level moisture. This all suggests an uptick in lake effect/CAA advection type snow showers…the most concentrated snow will probably be over the higher terrain in the secondary and primary Snowbelts where orographic lift will improve the odds of snow showers developing.

 

 

In addition, a surface trough may also drop across the lake Saturday evening, acting as another source of potential increase snow showers downwind of the lake. This surface trough passage does appear to correspond to another increase in low level omega as shown in the NAM overview image above (where I drew a circles and got excited over omega in the DGZ early Saturday afternoon).

 

 

Lake effect conditions remain favorable through Saturday evening, so it’s not inconceivable that the vort max passage/mid-level moisture increase and surface trough passage all combine to allow half decent lake effect snow showers to continue through much of Saturday evening, especially in the higher terrain where the NWrly winds will cause good orographic lift. On the sounding above the winds appear to be sheared, but that’s more a product of the trough passing (winds become better aligned again later). The winds veering with height suggests low level convergence along the surface trough…winds over the lake will be closer to the mid-level winds (hence more northerly) due to less friction over the water/ice and slightly warmer temperatures (due to whatever heat flux occurs from the lake to atmosphere)…the warmer temperatures promote mixing of the more northerly winds aloft to the ground. Winds over land will be lighter and NW as opposed to N…convergence near the shore where the two meet.

 

Later Saturday night, inversion heights and moisture depth decrease quickly, so lake effect should decrease to just flurries after midnight. An exception may be under any Lake Huron band after midnight where light to moderate but very fine snow could continue into early Sunday.

 

As for snowfall amounts…2-4” synoptic for most. The lake effect is tough. The snowflakes will become very small and hence much lower ratio by late Saturday afternoon, so it will be hard to rack up good accums. The biggest crack in the ice is east of the Lake Erie islands, so to account for this I figured in 1-2” of fine lake effect snow as far west as parts of Lorain/Medina County to push totals to 3-5” here…could see a local 6” total on the west side if a band forms intensely enough before the dendritic growth becomes very low. Farther east, with better terrain and potential Lake Huron moisture, even with the lower ratio of the snow, I have to figure at least another 2-4” of lake effect snow in the higher terrain of the primary Snowbelt. Even though there’s ice on the lake, there’s a lot suggesting decent snow will continue well into Saturday evening, especially in the higher terrain…so I painted in 4-7” here. The only way there’s more is if the Lake Huron connection is better than I think.

 

As for impacts…winds will gust 30-40MPH behind the arctic front into Saturday evening before gradually decreasing. The snow will become increasingly fine Saturday afternoon and evening, which when combined with the wind could cause significant visibility restrictions into Saturday evening before a gradual improvement occurs. The falling snow and likely extensive blowing snow will cause roads to be very slick from late Saturday morning when the arctic front drops through into Saturday night. Wind gusts and visibilities may arguably push blizzard conditions where lake effect sets up Saturday afternoon and evening, although it may be hard for many spots to actually verify 3 hours straight of 0.25 mile or less visibility and 35MPH wind gusts…but some places will be close.

 

Map above. As I typed that I almost got worried I'd be a tad low in spots, we'll see. Should be fun, expecting a nice squall down here too

[OHweather]

Hopefully this link still works in the AM...Andre on Fox 8 showed a time lapse from the crib, definitely some movement of the ice and what appears to be an area of open water

 

http://fox8.com/2015/02/13/brutal-cold-temps-begin-moving-in-tomorrow/

[OHweather]

CLE's AFD isn't out yet, so I probably won't read it unless it's out soon because even I am going to sleep shortly. However, I'm really eager to figure out their reasoning for what they just did with their headlines.

 

They issued a winter storm warning for Ashtabula County and NW PA. I'm cool with that (they issued the warning until 7PM Sunday and the WSW "includes the wind chill"  and didn't issue any wind chill headlines there, but I've heard that offices in general don't try to issue multiple headlines on top of each other, so I won't say anything about that). For the rest of NE Ohio, they issued a wind chill warning starting noon Saturday. Based on the wind chills, I'm also cool with that.

 

However, they didn't issue any winter weather advisories or winter storm warnings for anywhere else. This makes no sense to me (again though, maybe they have some reasoning other than "advisory criteria is 4 inches so we 'can't' issue an advisory for 2-4 inches", that's what I will respectfully call not helpful to the public). They may try to say that the "wind chill warning involves the snow" (which would be the first time I've heard that), however the wind chill headlines kick in at noon. There's a chance the squall along the front that will likely cause extremely hazardous conditions will be completely through Cleveland and Akron by noon. The wind chill product also does not mention blowing snow or low visibilities, which will be the biggest issues (as mentioned earlier, 2-4" of snow on its own isn't a big deal). The snow and blowing snow could continue well into Saturday evening in orographic lift areas and also the band that will probably set up on the west side downwind of the crack in the ice there.

 

Also, if they issued a winter storm warning for Ashtabula, they need to issue it for the rest of the Snowbelt. Due to the lack of higher terrain in much of Ashtabula County, amounts in Geauga County are almost always the same as or higher than amounts in Ashtabula County. The only exception is if a Huron band sits over Ashtabula County and doesn't move any farther west, or if a W-E type band just hugs the Ashtabula lakeshore. However, there is strong support for whatever Huron band develops moving into Lake/Geauga Counties. With ice on Lake Erie, terrain will be needed to ring out better lake effect snow. You have more terrain in far southern Lake County, Cuyahoga County and Geauga County (hell throw northern Medina in there too) than anywhere in Ashtabula County. This all suggests that if they issued a WSW for Ashtabula that they can extend it at least to Cuyahoga and Summit, if not even another row of counties west.

 

Maybe I shouldn't sit here at 3:30AM picking apart the NWS headline decisions, but I'm really at a loss right now. After trying to reason it out bits of brain actually started oozing from my nose. Oh well.

[Trent]

Picked up 2" of fluff overnight. This is super high ratio fluff. Can't wait to see what KCLE comes in with for an overnight total, likely a trace since the METAR didn't report any liquid equivalent.

Radar looks good for the main show about to begin shortly.

[NEOH]

Picked up 2" last night. Radar looking good. Snow keeps changing from fine flakes to larger ones.

Nice disco ohweather. Considering we have a couple inches down already your map looks great. Looking forward to the whiteout as the front passes.

[Trent]

Radar has just exploded. Huge fat flakes falling.

[NEOH]

Radar has just exploded. Huge fat flakes falling.

Yeah... Quickly flipped to parachutes. This will pile up quickly.

[OHweather]

If Trent already had 2" at 8AM I say no way he has less than 4" by 1PM. Intense squall line over the lake and decent snow showers continuing behind it all the way past Detroit.

[dta1984]

3.25" as of 930am. Arctic front is getting close. Should be a fun show!

[MAIDEsNow]

3.6" as of 10am.  

 

Actually quite nice out there as of now, mod snow, little wind, 23 degrees.  Cleared the deck & grill for steaks this evening, may be a little different weather story by then...

[LakeEffectOH]

Nice fat flakes here. Can't wait until the wind picks up!

[Trent]

If Trent already had 2" at 8AM I say no way he has less than 4" by 1PM. Intense squall line over the lake and decent snow showers continuing behind it all the way past Detroit.

 

Absolute white out there now. I'm up to 4.6". Just unbelievable there isn't an advisory out for this. 

[Trent]

I don't like to exaggerate, but this might be one of the heaviest snow rates I've experienced. Just incredible.

 

[OHweather]

Absolute white out there now. I'm up to 4.6". Just unbelievable there isn't an advisory out for this. 

Claridon in Geauga County already at 5.5" as of 11AM. The lakeshore counties will have 4-7" widespread by 1PM before any LES kicks in. Way too low on my forecast, but I still would've issued a warning.

[carumba]

Claridon in Geauga County already at 5.5" as of 11AM. The lakeshore counties will have 4-7" widespread by 1PM before any LES kicks in. Way too low on my forecast, but I still would've issued a warning.

I just went out to shovel the snow for some guests coming over today. I'd say here just south of Chagrin Falls we've got about 3 - 4" but it's blowing quite a bit. It's very light, very shovelable snow too.

[dta1984]

They sky just opened up! Heavy snow with huge flakes.

[OHweather]

Almost every traffic cam is just a wall of white in Cuyahoga County. Impressive squall.

[Trent]

Up to 5" on the dot here. Snow band seems to have shifted south of the immediate lakeshore. I hope KCLE accurately captures this snowfall today.

[dta1984]

Is it normal for the wind chill warning to be for snow amounts too? They have 4-8" in the warning.

[OHweather]

CLE did update their AFD at 11AM with much better reasoning and did hit the snow/blowing harder in the wind chill warning. I think by this point they were sort of bound by the wind chill warning issued last night without any winter weather advisories and didn't want to confuse people. I still stand by that a winter weather advisory or winter storm warning should have been issued for the snow, with wind chill warnings kicking in later, but it was nice to get a nice explanation and a mentioning of the snow/blowing in the wind chill warning...which wasn't initially done last night.

 

It's actually up to 35F here. Hoping we get unstable enough for a really nice squall in a couple of hours.

[OHweather]

Is it normal for the wind chill warning to be for snow amounts too? They have 4-8" in the warning.

I've never seen that before...I've seen a winter storm warning include wind chill but not the other way around. Like I said, I think they were sort of "stuck" once the wind chill warning was issued last night starting at noon. I may be wrong but that's the impression I got. The AFD actually almost directly discussed almost everything I took issue with in my post at like 4AM...I'm glad someone there finally explained what's going on with the snow and wind in some forecast products, but don't agree with no snow/winter storm headlines being issued off the bat.

[Trent]

Likely measuring problems at KCLE as the METAR didn't even have the "SNINC" mention. I was thinking they should have had 2" in the last hour.

 

KCLE 141651Z 35017G23KT 1/4SM SN FZFG VV005 M07/M09 A2960 RMK AO2 WSHFT 1551 SLP035 BLSN P0002 T10721094 $

[OHweather]

Likely measuring problems at KCLE as the METAR didn't even have the "SNINC" mention. I was thinking they should have had 2" in the last hour.

 

KCLE 141651Z 35017G23KT 1/4SM SN FZFG VV005 M07/M09 A2960 RMK AO2 WSHFT 1551 SLP035 BLSN P0002 T10721094 $

They came in with 0.9" last night. I'm sure they did get 2-3" last hour, but I'm also sure that 1.5-2.5" of that "blew away" from where they measure. We'll see what they come in with today.

 

There should be a general decrease in the snow soon as the band keeps sagging south, but snow showers and blowing snow will continue. We'll see if there's a nice uptick in LES by mid to late afternoon or if the lake is just too icy.

[Trent]

The accumulated precip maps show a swath of 0.3" liquid equivalent stretching along I-90 from Lorain County through downtown. There's even a small speck of 0.6" near Lorain. Considering what's fallen here, there must be a hefty total under the speck.

[Trent]

Snow has increased again along the shore. We'll see how long it lasts. With temperatures plunging below zero by the evening, it's going to be extremely treacherous. 

 

There's an outside chance that tomorrow's high will actually be colder than the record low for the date of -4.