Bob Chill Posted December 7, 2013 Share Posted December 7, 2013 I guess high and low range is ironed out with the initial wave. 1-4" of snow seems probable from the cities west. East of DCA needs the death band to get more than an inch from what I'm seeing. Uncertainty in the expanse and organization leaves no easy call on the high or low end. Column supports all snow for a 3-6 hour window. A good bit of zr is more of a lock than the snow portion. I'll go with the nam temps, gfs precip, and toss the euro. Link to comment Share on other sites More sharing options...
snow. Posted December 7, 2013 Share Posted December 7, 2013 I guess high and low range is ironed out with the initial wave. 1-4" of snow seems probable from the cities west. East of DCA needs the death band to get more than an inch from what I'm seeing. Uncertainty in the expanse and organization leaves no easy call on the high or low end. Column supports all snow for a 3-6 hour window. A good bit of zr is more of a lock than the snow portion. I'll go with the nam temps, gfs precip, and toss the euro. we don't have thermals, but my guess is the euro is the coldest in the mid levels of all 3 models....the NAM torches pretty quickly.... In terms of precip through 45 hours and warm nose NAM - wettest and warmest GFS- middle and middle Euro - driest and Probably a tad colder than GFS right now I would toss the NAM completely and take a Euro/GFS blend (taking about 80% of average QPF and doing a slight DCA suck adjustment).....so for DCA for instance, flip is probably around 19z, and precip is in the 0.15 - 0.18" range....I went 0.7" in the contest but I think around an inch is probably a good forecast for DCA right now....1.5" wouldn't shock me...neither would 0.5"... I think the flip will occur metro wide pretty uniformly.....north of a line from BWI - HGR should stay snow a bit longer....but it isn't like IAD will be snow all that much longer than DCA...both airports are torching at 21z in the warm nose.... Link to comment Share on other sites More sharing options...
Ian Posted December 7, 2013 Share Posted December 7, 2013 yeah--i think our range locally is basically around 0.5" to around 2" ... which probably means a bulls eye of higher and i'm not really looking into the hills, just the general DC metro goal is like a good 30 to 60 minute period of like 1" per hour rates. Link to comment Share on other sites More sharing options...
snow. Posted December 7, 2013 Share Posted December 7, 2013 yeah--i think our range locally is basically around 0.5" to around 2" ... which probably means a bulls eye of higher and i'm not really looking into the hills, just the general DC metro goal is like a good 30 to 60 minute period of like 1" per hour rates. could happen...SREF is out and it is uber wet just a hair after we flip....we probably flip from snow around 19-20z.....so about 0.15-0.20 before the flip which is in line with the blended globals....but I like the idea of a fat thump even if it is sleet because I like heavy precip...I'd almost like a NAM type scenario where we might not get any more snow, but we get pummeled with heavy sleet...should be fun no matter what unless the precip is spotty and awful Link to comment Share on other sites More sharing options...
clskinsfan Posted December 7, 2013 Share Posted December 7, 2013 OK. After all of the guidance. I think its a given that me and winterwxluvr are going to lose our electricity at this point. I have a party to go to tomorrow. So I just wanted to say good luck and I will "talk" to you all in a few days. Link to comment Share on other sites More sharing options...
Bob Chill Posted December 7, 2013 Share Posted December 7, 2013 I think we're all on the same page. 1" line running 95 and up to 4" tops somewhere west. This includes sleet. WAA pecip can have some upside surprise. Not saying I think someone gets more than 4. Just that maybe more people get 1-2 instead of 1 or less but that is a best case scenario based on today's guidance. But I would be hardly surprised for a bit of a miss on the front wave and us close in folk miss the incredibly high 1" benchmark. Link to comment Share on other sites More sharing options...
yoda Posted December 7, 2013 Share Posted December 7, 2013 Cause I am somehow still awake for it, 06z NAM through 27 has the 0c 850 line on NC/VA border. 27 hr sim radar makes it look like the "finger" of precip is pointing directly at DCA Flurries/Virga in N VA at hr 30 (12z SUN) Link to comment Share on other sites More sharing options...
snow. Posted December 7, 2013 Share Posted December 7, 2013 Cause I am somehow still awake for it, 06z NAM through 27 has the 0c 850 line on NC/VA border. 27 hr sim radar makes it look like the "finger" of precip is pointing directly at DCA Flurries/Virga in N VA at hr 30 (12z SUN) it gets in early..an inch of snow in the western burbs by 10am Link to comment Share on other sites More sharing options...
yoda Posted December 7, 2013 Share Posted December 7, 2013 it gets in early..an inch of snow in the western burbs by 10am Snow sounding at DCA through at least 1 pm... decent QPF... 0.25 in N VA into DCA by then Pinging by 21z at DCA... prob at 20z is switchover to sleet Link to comment Share on other sites More sharing options...
snow. Posted December 7, 2013 Share Posted December 7, 2013 Snow sounding at DCA through at least 1 pm... decent QPF... 0.25 in N VA into DCA by the..mo it's dry compared to 0z ....more in line with the other models Link to comment Share on other sites More sharing options...
yoda Posted December 7, 2013 Share Posted December 7, 2013 it's dry compared to 0z ....more in line with the other models Agree... looks like .3 QPF is snow on intial wave before changeover to sleet? DCA below freezing through 12z MON at 30/31... looks like we sneak into mid 30s by 18z MON Link to comment Share on other sites More sharing options...
Jebman Posted December 7, 2013 Share Posted December 7, 2013 all along, my gut was telling me I'd probably end up with about a half inch of snow and maybe a glaze. Link to comment Share on other sites More sharing options...
NoVaWx Posted December 7, 2013 Share Posted December 7, 2013 Give me two inches that sticks everywhere rather than four that only gets on some grassy areas. Last years snowfall total imo was 0.0". It snowed sure but the street only got dusted once and the grassy areas never got any solid coverage. Link to comment Share on other sites More sharing options...
needbiggerboat Posted December 7, 2013 Share Posted December 7, 2013 6z runs look nasty for IAD area. A few inches of snow followed by a significant period of frz drizzle, with GFS a touch colder. I'm always skeptical of icing potential around here, but this one seems to have legit potential. Link to comment Share on other sites More sharing options...
BristowWx Posted December 7, 2013 Share Posted December 7, 2013 6z runs look nasty for IAD area. A few inches of snow followed by a significant period of frz drizzle, with GFS a touch colder. I'm always skeptical of icing potential around here, but this one seems to have legit potential. Agree a couple inches of snow would help lock the low level cold especially after dark to set that stage for some icing. Link to comment Share on other sites More sharing options...
TSSN+ Posted December 7, 2013 Share Posted December 7, 2013 6z runs look nasty for IAD area. A few inches of snow followed by a significant period of frz drizzle, with GFS a touch colder. I'm always skeptical of icing potential around here, but this one seems to have legit potential. Gives me .6" ZR. ice ice baby. Link to comment Share on other sites More sharing options...
usedtobe Posted December 7, 2013 Share Posted December 7, 2013 The models haven't really changed my thoughts from yesterday's CWG discussion. How low the precip stays sleet is tricky as the models bring in a dry layer and the saturated layer above the warm layer does not get below -8C which usually means freezing rain as you can't form the initial snow crystals. Link to comment Share on other sites More sharing options...
winterymix Posted December 7, 2013 Share Posted December 7, 2013 There are significant differences between the 06Z NAM and 06Z GFS. The NAM brings in the initial snow 2 or 3 hours earlier and keeps the surface below freezing 3 to 5 hours longer than the GFS. More importantly, the GFS dries out on Tuesday and the NAM goes bonkers. Link to comment Share on other sites More sharing options...
WxMan1 Posted December 7, 2013 Share Posted December 7, 2013 I think you meant freezing drizzle Wes Yeah, my thoughts haven't changed much either, actually going back a few days now. I'm still not expecting as prolonged of a SN or SNPL period as some of the models would suggest IMBY, and I don't expect the IP to be around very ling either. At this point I will gladly take 1-2" of snow and sleet, although my hunch continues to be closer to 1" or less. That warm nose aloft typically comes in faster and more vigorously when we've got more SW flow aloft and to our north (weaker mid level FGEN). There are a few conceptual signatures @ 500 mb by 18-21Z that certainly grab my attention in supporting more liquid pcpn overall (FZRA) with a faster vs. slower transition: SW/WSW flow well north into northern New England and southern Quebec, a bubble/shortwave ridge developing over the GL, and 582 DM heights into Cape Hatteras. IMBY I think the real question is going to be how much ice accretion. The Crofton-Bowie area may sit near 32 for a while Sun evening well into Monday, but depending on the pcpn rates, it's awfully tough to get significant ice buildup with temps so marginal, even along elevated surfaces including trees and power lines. Farther west of 95 (above the fall line), I would think chances of hitting at least .25" of ice go up significantly. The models haven't really changed my thoughts from yesterday's CWG discussion. How low the precip stays sleet is tricky as the models bring in a dry layer and the saturated layer above the warm layer does not get below -8C which usually means freezing rain as you can't form the initial snow crystals. Link to comment Share on other sites More sharing options...
olafminesaw Posted December 7, 2013 Share Posted December 7, 2013 Gotta love the cutoff on the 12z nam. (although if you average the earlier runs which put the heavy snow "finger" north of us and this run you get jackpot.) Link to comment Share on other sites More sharing options...
Huffwx Posted December 7, 2013 Share Posted December 7, 2013 NAM coming around to a more ominous solutions for my area ice wise. Had been sleety and dry slot ish. Link to comment Share on other sites More sharing options...
wxmeddler Posted December 7, 2013 Share Posted December 7, 2013 Back to the N of I-70 shafted solution. Link to comment Share on other sites More sharing options...
Ian Posted December 7, 2013 Share Posted December 7, 2013 NAM kinda sucks overall. Link to comment Share on other sites More sharing options...
Ian Posted December 7, 2013 Share Posted December 7, 2013 NAM kinda sucks overall. NAM kinda sucks overall. well unless you're south of DC and believe weatherbell Link to comment Share on other sites More sharing options...
stormtracker Posted December 7, 2013 Share Posted December 7, 2013 Congrats Wes Link to comment Share on other sites More sharing options...
TSSN+ Posted December 7, 2013 Share Posted December 7, 2013 Amazing how the models work. GFS went more south at 0Z, came back a bit north at 6Z. Nam was north now going south. Figures. Link to comment Share on other sites More sharing options...
Bob Chill Posted December 7, 2013 Share Posted December 7, 2013 One of the nam's better features is the option to toss or hug within about an hour after the run is finished. Link to comment Share on other sites More sharing options...
DCAlexandria Posted December 7, 2013 Share Posted December 7, 2013 Ian South DC and south do great on that map. Link to comment Share on other sites More sharing options...
DCAlexandria Posted December 7, 2013 Share Posted December 7, 2013 One of the nam's better features is the option to toss or hug within about an hour after the run is finished. Meaning it's going to be a now cast where that band sets up. Link to comment Share on other sites More sharing options...
Ian Posted December 7, 2013 Share Posted December 7, 2013 Ian South DC and south do great on that map. it's wrong though. that's not all snow. the flip is pretty quick still. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.