metallikat34

Don't pay so much attention to the current motion, but rather the expected motion of the bands from 12-6am. Remember, the last and strongest wave of low pressure hasn't fully formed yet. And I keep going back to just how "spun up" the atmosphere is around the British Isles right now. Look at this digging piece of energy north of Ireland, moving in a completely opposite direction as the storm and frontal system less than 50 miles to the east. The reach back or pivot will happen. But yeah, some of those crazy GFS totals aren't going to happen.

Same here. Been light snow all night, but starting to pile up. Another 3-6 hours at this rate should squeeze out an inch or two more.

Yeah that is such a sharp cut off on the backend! I think the winners and losers from this storm aren't going to be separated by many miles.

Also a good sign that so many are seeing snow from this initial low pressure wave. The next (and final) low pressure wave will be the main event and figures to be a few mb stronger. Good support for continued or even enhanced precipitation rates after midnight.

Snowing and sticking (at least on the sidewalks) here in Morningside. A nice moderate snow too!

That was me! And yes, I think its not going to add any "energy" to our precipitation chances tonight. But just how far it digs south will play a big factor in how far north the snow shield makes it.

I've been watching the WV imagery as well. I don't think we should discount that digging short wave northwest of Ireland. The same feature helped feed that divergence band that sat over Scotland last night. It looks to be a player again in the orientation and progress of the front. But yeah, we are in a key make or break window now!

Yup. I don't want to be a downer, but I think we should all be prepared for a big bust overnight.

Still don't like this low position from the 12Z GFS run. Shunting all the good precipitation rates to northeast England.

Interesting! I just got back from your suggested run up to Warklaw Hill. Was quite nice, but very muddy and wet! On that note, almost no difference in temperature up to 200+m this afternoon. A very uniform low level atmosphere at the moment. Haven't had a look at any afternoon guidance, but i am still concerned that the best precipitation gets pulled eastward.

Never heard of him until yesterday, but he seems to be a bit notorious on these chats? Not sure if thats a good or bad thing....

It feels like a crime posting my own twitter thread.....but here I am. Posted this mini analysis just now.

Thinking of coming up your way for a late morning snow run! Just a lot of slush down here in Morningside

Yeah I am worried that tonight will be a miss for a lot of us.

I am really having a think about this now. Could tonight be the main event? This band is in prime position and isn't moving. And it's being fed plenty of moisture. Tomorrows "Christoph" is going to be a deepening low pressure system that will likely drag a lot of precipitation eastward as it moves across the UK. Sometimes these precursor events end up being the main event.

Same down here as well. At least an inch now. Expecting this to last for a good 3-4 more hours as well. Quite the event!

I think it's safe to say this event has over performed tonight. Look at that flow of moisture from that digging low pressure system south of Iceland. It's just feeding right into this band that's nearly stationary over the central belt. This mini fire hose won't shut off for at least a few hours. Ironically, I wonder if tonight might end up being the bigger snowfall event.

I thought we never did well on snow with frontal events

Quite true!

Finally starting to stick here! 0.5 air temp and 0 dew

Wow! Looks like a good haul up there.

Temp? I've just switched to sleet/snow(ish) here, but definitely not sticking

Was just looking at the ECMWF as well. Definitely a more reasonable and likely snow scenario, and not as juicy as the GFS. One of the big differences between the GFS (top) and ECMWF (bottom) has been the position of the low pressure, shown here for 6am on Thursday. ECMWF and the UKMet have had a much more progressive solution, with the low pressure being shunted further the south as it hits the water. GFS has been showing a position more to the northwest. The ECMWF/UKMet solution is more believable given the somewhat open nature of the low pressure wave. So a low pressure positioned a bit further to the south and east isn't a complete deal breaker as its still close enough and strong enough to produce precipitation. The 925mb temps are marginal, but may actually be helped to trend a bit colder given that low position. Expecting a sharp cut off somewhere between 50-100m, but should be a pretty good event for elevated areas. Haven't had a close look at the thermal profiles, so I am not sure how much sleet/grauple will mix in, even at higher elevation. Again, I am a big believer in the diurnal bump! Don't buy the GFS totals given the likely error in low position and the likely errors in the boundary level thermal profiles adding to a "juiced" up precipitation totals. I miss model watching for these events! Growing up in Boston in the US, this was my favorite thing to do pre winter storms!

Watching the GFS come in now. I mean, the run to run snowfall output has been quite high and very consistent. But really, how much of this is snow and how much is just being represented as snow by the precipitation type masking? I don't know. But the GFS is likely way too bullish on this being all snow, which suggests some errors in its thermal profiles. And then of course there is the position of the low pressure system as it moves from the midlands to the coast early Thursday morning. Since it will be a deepening low developing along a frontal system, I don't trust any of these models with regards to low pressure position.

Lol. I am ready! I am over caffeinated and procrastinating at "work".