lpaschall Posted January 17, 2018 Share Posted January 17, 2018 33 minutes ago, losetoa6 said: Not surprising..it's been virga here for an hour or 2 . Winds out of the west not a good sign either. Probably will cut things off quickly Coming down nicely as of 10 min ago. Best rates of the winter so far. Deck covered already. Link to comment Share on other sites More sharing options...
AfewUniversesBelowNormal Posted January 17, 2018 Share Posted January 17, 2018 radiation index is about a 10. Big time wet snow event. Last night conditions were perfect, and no wind! Link to comment Share on other sites More sharing options...
poolz1 Posted January 17, 2018 Share Posted January 17, 2018 8 minutes ago, WVclimo said: Snow is tapering off. 1.2" on 0.08" liquid. For all those numerous runs of the NAM and RGEM that showed 0.20-0.40" of QPF, the GFS and the last 48 hours of Euro runs were much closer to what fell. Thats a gradient! To say I have a dusting is being generous and you are barely 10 miles to my NW. Light snow. 30* Oh well.... You lose some, you lose some.. Link to comment Share on other sites More sharing options...
NorthArlington101 Posted January 17, 2018 Share Posted January 17, 2018 Good to see the Reistertown mPING report as soon as they got under some returns. To get anything tonight in the snow hole (0z NAM showed it too) we will need to minimize virga. Link to comment Share on other sites More sharing options...
winterymix Posted January 17, 2018 Share Posted January 17, 2018 Here I am and no snow yet, pregnant though. (39.474331, -76.797151) Link to comment Share on other sites More sharing options...
wxdude64 Posted January 17, 2018 Share Posted January 17, 2018 Should have known with the lowering DP's earlier.......snow evaporating off radar to my west. I am done with 10 minutes of pixie dust. Fully expect to see snow blossom on a Richmond to Greensboro line within the hour. Classic, classic transfer for here. MAYBE it can back in to here, but that would be asking a lot, kudos to the King, nailed it. Link to comment Share on other sites More sharing options...
WVclimo Posted January 17, 2018 Share Posted January 17, 2018 9 minutes ago, poolz1 said: Thats a gradient! To say I have a dusting is being generous and you are barely 10 miles to my NW. Light snow. 30* Oh well.... You lose some, you lose some.. Sorry you weren't able to get in on it, Poolz. It's a very fluffy snow. Doesn't even stick to your shoes. I think another 10 miles to my NW, in the Big Pool/ Ft. Frederick area, they probably picked up twice what I have here. Crazy how little the precip shield moved all day. Link to comment Share on other sites More sharing options...
ldub23 Posted January 17, 2018 Share Posted January 17, 2018 10 minutes ago, Amped said: Wow models really barfed on the closed H5 low in the short range. Won't matter for us, but makes a pretty big difference for S VA and NC Even more snow there? Link to comment Share on other sites More sharing options...
Chris78 Posted January 17, 2018 Share Posted January 17, 2018 39 minutes ago, Amped said: Big gradient across the mountians if there's 1.5" in smithtown and nothing here or in Westminster. Starting snowing lightly around 4pm. Occasionally moderate but mostly light stuff. Looks like a total of 1.75. Link to comment Share on other sites More sharing options...
clskinsfan Posted January 17, 2018 Share Posted January 17, 2018 Looks like I am about done out here. Ended up with .2. This winter sucks. Link to comment Share on other sites More sharing options...
AfewUniversesBelowNormal Posted January 17, 2018 Share Posted January 17, 2018 01z RAP is closer to giving us a SECS with coastal low than other model runs, 00z was much different. We would have to cool down a lot..... Link to comment Share on other sites More sharing options...
Chris78 Posted January 17, 2018 Share Posted January 17, 2018 42 minutes ago, WVclimo said: Snow is tapering off. 1.2" on 0.08" liquid. For all those numerous runs of the NAM and RGEM that showed 0.20-0.40" of QPF, the GFS and the last 48 hours of Euro runs were much closer to what fell. Yep. I was hoping for once they would be right. Some of there runs over the last 2 days gave me 4 to 6 inches. GFS and Euro nailed the liquid aspect of it out our way. Link to comment Share on other sites More sharing options...
Amped Posted January 17, 2018 Share Posted January 17, 2018 All models did this, but here is the NAM valid in 24hrs. Quite a change from 12z. Unfortunately not going to help us. EDIT: CMC had close to the correct depiction, GFS Euro and NAM didn't do to well. Link to comment Share on other sites More sharing options...
mappy Posted January 17, 2018 Author Share Posted January 17, 2018 After an hour of virga, -SN now Link to comment Share on other sites More sharing options...
Mrs.J Posted January 17, 2018 Share Posted January 17, 2018 Started over here in Frederick about an hour ago. Grassy surfaces and sidewalks have a dusting. The roads were treated and seem to be fine for now. Link to comment Share on other sites More sharing options...
Mimiof2 Posted January 17, 2018 Share Posted January 17, 2018 34 minutes ago, Chris78 said: Starting snowing lightly around 4pm. Occasionally moderate but mostly light stuff. Looks like a total of 1.75. Wow....we got a dusting here in the Southern end of the county Link to comment Share on other sites More sharing options...
yoda Posted January 17, 2018 Share Posted January 17, 2018 Lol Prince William just declared 2 hour delay Link to comment Share on other sites More sharing options...
Chris78 Posted January 17, 2018 Share Posted January 17, 2018 2 minutes ago, Mimiof2 said: Wow....we got a dusting here in the Southern end of the county The cut off was crazy. Watching radar most of the afternoon route 70 was the deviding line with the training of echos. Link to comment Share on other sites More sharing options...
Staged Posted January 17, 2018 Share Posted January 17, 2018 Finally have some light snow in Leesburg/ landsdowne edit, Aaaannnndddddd, it's over lol. Link to comment Share on other sites More sharing options...
feloniousq Posted January 17, 2018 Share Posted January 17, 2018 Nice, steady, five-flake-per-minute pace. This should really stack up. Link to comment Share on other sites More sharing options...
WEATHER53 Posted January 17, 2018 Share Posted January 17, 2018 Heavy precip down tx/la/ms and watch national radar 12 hour; like balls or streams of moisture firing off but can't hit us Be great to get that main mass down there up here Link to comment Share on other sites More sharing options...
WEATHER53 Posted January 17, 2018 Share Posted January 17, 2018 5 hours ago, Tenman Johnson said: You do not need models right now. Since noon the radar has shown little eastward movement. Our only hope is the area down in Tennessee which picked up some moisture early this afternoon and does have some eastward component to it It's getting close Link to comment Share on other sites More sharing options...
Stormpc Posted January 17, 2018 Share Posted January 17, 2018 First flurry, west of Woodbridge. 31.4. Link to comment Share on other sites More sharing options...
WEATHER53 Posted January 17, 2018 Share Posted January 17, 2018 It's funny but right this instant there are radar returns from just nw of Richmond to Lancaster PA except for a blank area right around D.C. Link to comment Share on other sites More sharing options...
Cobalt Posted January 17, 2018 Share Posted January 17, 2018 Just now, Tenman Johnson said: It's funny but right this instant there are radar returns from just nw of Richmond to Lancaster PA except for s blank area right around D.C. Looks like it's trying to fill in, but mostly virga. Looks like decent returns to the South, but not sure if virga or not either. Link to comment Share on other sites More sharing options...
BTRWx's Thanks Giving Posted January 17, 2018 Share Posted January 17, 2018 1 minute ago, Tenman Johnson said: It's funny but right this instant there are radar returns from just nw of Richmond to Lancaster PA except for a blank area right around D.C. It's beginning to merge. Link to comment Share on other sites More sharing options...
RichmondTarHeel Posted January 17, 2018 Share Posted January 17, 2018 Flurries in Fairfax Link to comment Share on other sites More sharing options...
Cobalt Posted January 17, 2018 Share Posted January 17, 2018 HRRR has been steadily increasing snowfall, and now has 0.5" (10:1 ratio), just West of DC. Probably not worth much, but it would fit what we're seeing with that light band of snow creeping North, and of course reports of flurries. Link to comment Share on other sites More sharing options...
cae Posted January 17, 2018 Share Posted January 17, 2018 Unless some sort of miracle happens, this will be my last post on what I think is going on in the atmosphere. This is for people like me who are just trying to figure this stuff out. Those of you who know what you're talking about, please correct me if any of this looks wrong. I apologize in advance for the length of this post and the number of images. I'm going to compare two Euro runs: 00z on Sunday night and 12z today. 00z on Sunday was a better run for our region. I'll first show some gifs for 12z tomorrow, or 7:00 in the morning. The firsts shows four images in order: 1) Precipitation over the last 3 hours from the 00z run. 2) The winds at 850 mb from the 00z run. Notice that around DC they're coming from the south, bringing moisture with them. 3) The winds at 850 mb from the 12z run. Notice that around DC they're coming from the west, bringing dry air. 4) Precipitation over the last 3 ours from the 12z run. The dry air has shut of precip around DC. Notice what happens between 2) and 3) above. There is a small dip in the 850 mb winds just to the east of Toronto. In the 12z run, it pushes down a little more, getting the DC area into the western flow and cutting off our snow. I've mentioned this all before, and PSU had a very nice explanation this morning that the shift in winds is related to the development of the first wave, which manifests itself on the surface as the coastal that hits areas to our north. I've been trying to figure out how this shift relates to all of the H5 maps we're always looking at. So the next couple of gifs will start at the 850 mb wind maps shown above and go up to the 500 mb level to see what happens. Let's start with the 12z (no snow) run first. Pay attention to what is happening near Toronto. The images in this gif are, in order: 1) The winds at 850 mb from the 12z run. This is the same as 3) above. 2) The winds at 700 mb from the 12z run. Notice how you can still see a "dip" in the winds near Toronto. I believe this is the first wave PSU was talking about, or something close to it. 3) The winds at 500 mb from the 12z run. Notice how the speeds appear to be pinched just below Toronto. I believe the dip just above the pinch is related to the similar features at 700 and 850 mb. The H5 is just about to close off, but to see that we need to look at the geopotential height plots. That's what we'll see in 4)-7). 4) The H5 map corresponding to 3) above. 5) The H5 map 3 hours later. 6) The H5 map 3 hours later. Now we can see a closed contour forming near the KY/VA border. 7) The H5 map 3 hours later. We can clearly see the closed contour, with the split occurring near southern PA. Next let's look at the same thing for the 00z (more snow) run. The images in order are: 1) The winds at 850 mb from the 00zz run. This is the same as 2) in the very first image. 2) The winds at 700 mb from the 00z run. The dip near Toronto is less distinct. 3) The winds at 500 mb from the 12z run. The pinch in the wind speeds is gone, or at least hard to spot. 4) The H5 map corresponding to 3) above. 5) The H5 map 3 hours later. 6) The H5 map 3 hours later. Unlike the 12z run, there is no clearly closed contour. 7) The H5 map 3 hours later. H5 has closed off, but now the split has occurred near southern NY. So now we (finally) get to the insight I think I've gotten out of all of this. In the 00z run, even though H5 appears to close off later, we get more snow. Why? I think the answer has to do with the two different sides of the H5 split. Up until now, I'd always paid attention to the bottom half. Closure in H5 favors greater circulation near the bottom half of the split, which can generate winds coming from the east. That's good around here. But I'd never paid much attention to the top half of the split. I suspect that the top half of the split is more likely to produce winds that come from the west at lower levels, as opposed to winds that come from the south (if there were no split). In the 00z run, where the top half of the split stays farther north, so did the winds from the west at 850 mb. In the 12z run, the top half digs farther south, and I think this is associated with the southern shift in the winds from the west. So I think I may have been hoping for the wrong thing. I wanted to see H5 close off to get the easterly winds. But now I think the wave associated with the top half of the split actually ended up producing our winds from the west. In a sense, this all comes back to what PSU said. We just happened to be caught between the two waves at the worst place. My takeaway from this is that H5 closing off is not always a good thing - it could indicate trouble at the lower levels, depending on where you are relative to the split. If you've read this far, thanks. And to the more knowledgeable readers, I apologize for the non-technical language. I hope you were able to follow along. Link to comment Share on other sites More sharing options...
cae Posted January 17, 2018 Share Posted January 17, 2018 I just went outside, stared for a while, and finally saw the snowflake I've been tracking all week. 33/30 here with a flurry. Link to comment Share on other sites More sharing options...
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