RIC Airport

The 12Z Euro has the snow band arriving tomorrow morning, but the bulk of the precip doesn't enter the Richmond area until around 3 or 4 pm The heavier rates from north to south are between 7pm and 1am. Surface temperatures are above freezing when the precipitation starts but drop near freezing as the snow begins. The snow band didn't hang around as long as the GFS did before lifting north. GFS has an earlier arrival of the snow (heavier rates), which helped keep surface temperatures lower.

Here is the National Blend of Models (NBM). It runs every 3 hours, and it's basically a time-lagged blend of at least a few dozen models and ensembles. It still likely has some 06z or earlier guidance. It slowly responds if guidance continues to trend up or down, but it's what the NWS uses and should correlate to what you see in your point-and-click forecast. FWIW, here are the last two runs.

I like how the over-running from the initial wave seems to be "trending." Of course, some models have fluctuated with how far south it developed. The farther south, the better for us, and maybe even as far SE as Newport News/Hampton. Some models have the band advancing north into NoVa and dry-slotting us quickly, while others have it lingering longer around Richmond. Some models have surface temp and 850/925mb temp issues for parts of the Richmond area, while others have the column below freezing for the entire initial wave. Also, the timing of the precip is slightly different from model to model. What was a Tuesday event is now solidly a Monday one on some. I am not a pro, but I imagine trying to put out a forecast would be frustrating. I have given up hope on the coastal low. It could enhance precip to an extent, but I agree that most of the precip is from the initial wave vs the coastal.

12Z still had it. Actually, the past few runs of the GFS. I want to get excited once the Euro catches on, which is possible. I noticed the 6Z EPS improved from the 00z EPS for Friday. But, since 6z EPS only goes out to hour 144, it only captured some of the event.

Thank you, nice to wake up to a jackpot run.

The 00Z Euro is similar to other models in that it has the initial snow band developing Monday over the Richmond metro and quickly moving north. Some rain could fall on the southern end of the band south and east of Petersburg and West Point. Euro has the bulk of the precip moving into the metro area after about 7 or 8pm, but it only hangs around for about 5-6 hours before taping off. Euro was also warm at the surface (33-34°F) around Richmond, so unless there are good rates, it could make accumulations more difficult. It's looking more like the DC metro area could be the winner with this wave. Light rain spreads over Hampton Roads and NE NC Tuesday morning into the afternoon as the coastal low develops and begins to pull away. The Euro also had the Friday storm, but the snow was confined to NoVA and basically became a 40N storm. But it is something to monitor in the next couple of days.

Not really seeing any big changes on the 00z GFS for the Monday-Tuesday event. It still has snow arriving as early as Monday morning with periods of snow into Monday night and possibly a heavier burst of snow Tuesday morning before tapering off.

Tracking that, I just posted the HRRR since it's now coming within its range. It's always interesting to see how the short-range models start off. I did see the 3K NAM and liked it less for Richmond, especially if you are south and east of US Hwy 360. The model has the band forming right over the metro area and quickly moving north. It also has a warm layer at 925mb, which means Richmond could mix even though surface temps are at freezing during the precip band. As the band shifts north, surface temperatures rise above freezing Monday night as the coastal looks to be taking over off the SE coast, and we are dry-slotted in between.

The 00Z HRRR, which only goes out 48 hours, has a similar scenario, however, snow arrives earlier on Monday. Surface temperatures remain below freezing from when any precip starts until the model ends for areas north and west of Petersburg and West Point. Like the 18Z GFS, HRRR has the 925mb and 850mb temperatures remaining below 0°C along and north of a line from about Petersburg to West Point. Precip is still falling when this run ends, but the snow map (assuming a 10:1 ratio) has a band of 1-2" of snow from about Farmville to Tappahannock and Northern Neck by 7pm Monday evening.

AKQ favors areas north and west of Williamsburg for accumulations.

For the initial band, the 18Z GFS has surface temperatures at 33-34°F in the Richmond area and upper 30s to around 40°F once you get south and east of Williamsburg, as the bulk of the snow falls Monday evening into Tuesday morning. So, hopefully, the rates are heavy enough to overcome marginal surface temperatures to accumulate. The heavier rates, at least this run, look to occur from about 1am to 7am Tuesday, which helps, but the farther south and east you live, the harder it might be to accumulate. The 925mb and 850mb temperatures remain below 0°C along and north of a line from about Petersburg to West Point, further indicating areas north of there have better chances for sticking.

The surface depiction on the 18Z GFS isn't much different from the 12Z run. The initial band comes on Monday afternoon, with light snow, maybe a brief period of moderate rates, continuing into Tuesday morning. As in earlier runs, the coastal low develops too far offshore, so we do not get additional precipitation. It could be in southside Hampton Roads and NE NC, but it doesn't look cold enough for snow. We should all just root for maximizing snow accumulations with the initial band.

The short-term models are getting further within range, and so far, the 3K NAM is developing and pushing that initial band farther north of Richmond while everyone S and E see little, if anything. Meanwhile, the HRRR was a little farther south. Both of these are at the end of their ranges, so I don't know if I'd take them too seriously for now, but something to watch in later runs.

Also, the EPS wasn't too encouraging for that Friday-Saturday threat.

We already talked about this. I also posted the maps for that event and the GEFS for that threat. Did you overlook it?

Still a snow signal on the 12Z EPS for Tues-Wed, but certainly not as aggressive as the 12 GEFS. EPS only has about a 40%-50% probability of 1" at RIC vs GEFS 80%.

I agree that the models have trended better for us with that wave. We needed the coastal to flare up faster, which would've enhanced our totals further Tuesday night into Wednesday morning. Definitely time for some fluctuations, but that 2nd scenario has looked less lightly. Also, the Euro was a big no for Friday and Saturday's storm. Maybe the EPS will offer some hope.

Euro still gives light snow from the overrunning with the initial wave, but the coastal low did not get going early enough to enhance the totals in Hampton Roads and NE NC.

This is a slowed-down gif of the 12Z GEFS from 12Z Thursday to 18Z Sunday. There are some good hits for Friday into the weekend, but you can also see some warmer, rainy members, especially S and E of RIC.

Also, the 12Z GEFS for Tuesday-Wednesday had RIC at an 80% probability of seeing 1" of snow.

Definitely alright. The initial wave looks to deliver for most of us, and once the coastal gets going, that provides another opportunity for coastal areas. Liking the trends. The best runs happen when I decide to skip them and get some sleep. The storm for the end of next week and weekend certainly can improve as well. I posted the snow accumulation map for the Friday-Saturday storm, and also the total this run of the GFS did for both events. Hopefully, we score higher. And as @Conway7305mentioned, there should be continued opportunities in the weeks ahead.

00Z GFS is hanging on to the snow threat idea. No need to really go into the specific details. Will continue to monitor over the next couple of days until other models align on a solution.

The 18Z EPS says don't close the blinds on Tues-Wednesday.

Very true, the 18Z GFS still likes accumulating snow as the coastal low pulls away. Some snow is moving into VA between 1pm and 4pm on Monday with the initial wave, even into the Richmond area between 4pm and 7pm. However, like the 12z run, most snow on Monday afternoon and evening primarily stays north and west of Richmond. Almost all of C VA and Hampton Roads get dry slotted between the snow that falls north and west of Richmond and the precip that begins to develop with the coastal low to our south and east. It’s not until the coastal low gets going Tuesday morning when rain begins to fall across eastern NC and the Hampton Roads area. But even that is limited and short-lived as 18Z GFS has most of Tuesday dry. But, as the coastal low deepens and begins to pull away, more precip breaks out across the state between 7pm and 10pm Tuesday. It had snow chances until about 7am in Richmond and 10am Wednesday over Hampton Roads and NE NC. 18Z GFS drops 1-2” across most of region (assuming 10:1 ratio, of course), especially in interior SE VA. The 18Z GEFS also still show a snow signal for Tuesday and Wednesday, definitely not giving up hope. Also, by tomorrow night at 00Z, the NAM begins to get within range so we'll begin to see what the short term models do with this set up.

Yeah, certainly wasn't ideal, but at least it didn't completely take away the snow. While I recognize it may not be a 6"+ event, I'm still rooting for an inch.