jc_cshmny Posted March 4, 2013 Share Posted March 4, 2013 This will be updated again at what time? Around 10pm I think...for time ending Wed 7:00pm. Link to comment Share on other sites More sharing options...
tdmorrow Posted March 4, 2013 Share Posted March 4, 2013 15z SREF Plumes went up across the board: APG from 8.68 to 9.83 BWI 11.99 to 12.99 IAD 14.47 to 15.19 DCA 12.62 to 13.09 Link to comment Share on other sites More sharing options...
dsnowman Posted March 4, 2013 Share Posted March 4, 2013 The NWS is just starting to update their grids. Using Centreville, VA as a reference point (some mentioned it earlier as a good place), they are calling for 3-5 inches Tuesday night alone. Which syncs with the above map of 8-10 for that area by 1pm. Looks like even that area will flip back/forth between snow/sleet/rain during the event. So they seem to be riding these higher GFS/NAM-like QPF totals. Link to comment Share on other sites More sharing options...
scratchart Posted March 4, 2013 Share Posted March 4, 2013 I just took a look at the model soundings for DCA. Outside of a mix of RASN at the start and maybe a mix of snow and sleet for an hour or less at 9z Wed. It is in fact all snow. It may mix at the very tail end with lower rates too. All in all 85-95% of the precip from the NAM is snow. As always.. it's the NAM. Perhaps this isn't the time or place for this question, but how could the NAM soundings be >85% snow on 2"+ QPF but spit out that clown map that shows maybe 3" of snow for DC? Wouldn't the clown map take the soundings into account? Link to comment Share on other sites More sharing options...
tdmorrow Posted March 4, 2013 Share Posted March 4, 2013 What will benefit us is that the timing of the most marginal temps seems to line up pretty well with the best vertical velocity and highest rates. Link to comment Share on other sites More sharing options...
gymengineer Posted March 4, 2013 Share Posted March 4, 2013 Perhaps this isn't the time or place for this question, but how could the NAM soundings be >85% snow on 2"+ QPF but spit out that clown map that shows maybe 3" of snow for DC? Wouldn't the clown map take the soundings into account? There are two types of clown maps---snowfall and snow depth.The snow depth ones are the much lower ones. For example, compare instantweathermaps' snowfall vs. snow depth map. Edited to add: I'm sure the snow depth ones have some melting algorithm based on the surface temperature (35 F at DCA verbatim from the NAM at 18Z). Link to comment Share on other sites More sharing options...
Ian Posted March 4, 2013 Share Posted March 4, 2013 Look at the time.. Ending 1:00 PM... Wed... that is only half of the period. kind dumb to have a map out for part of the storm but then again that map has always been kinda dumb Link to comment Share on other sites More sharing options...
eurojosh Posted March 4, 2013 Share Posted March 4, 2013 Perhaps this isn't the time or place for this question, but how could the NAM soundings be >85% snow on 2"+ QPF but spit out that clown map that shows maybe 3" of snow for DC? Wouldn't the clown map take the soundings into account? I don't think the clown maps are that complex - don't they just take QPF at 2m temps and run with it? Link to comment Share on other sites More sharing options...
wxmeddler Posted March 4, 2013 Share Posted March 4, 2013 Perhaps this isn't the time or place for this question, but how could the NAM soundings be >85% snow on 2"+ QPF but spit out that clown map that shows maybe 3" of snow for DC? Wouldn't the clown map take the soundings into account? Yes, but they do a very poor job at it. Often times they take surface temps way too seriously or on the flip side they put the rates too high. They also put out just the true snowfall. Which is not the case in the real world because of compaction; which with very wet snow can be quite significant. The only way to truly tell is with interval rates and looking at soundings. Edit: Also it doesn't consider the depth of the cloud and at what height and temperature your seeder feeders are. 1" precip of small plated snow from shallow clouds with tops of -7°C is way different from 1" of precip from 25kft tops with temps at -30°C and a tall dendritic growth layer. Link to comment Share on other sites More sharing options...
TalcottWx Posted March 4, 2013 Share Posted March 4, 2013 kind dumb to have a map out for part of the storm but then again that map has always been kinda dumb It spells out they aren't highly confident on full totals Link to comment Share on other sites More sharing options...
gymengineer Posted March 4, 2013 Share Posted March 4, 2013 Yes, but they do a very poor job at it. Often times they take surface temps way too seriously or on the flip side they put the rates too high. They also put out just the true snowfall. Which is not the case in the real world because of compaction; which with very wet snow can be quite significant. The only way to truly tell is with interval rates and looking at soundings. I believe that poster was just looking at snow depth maps. What you say about the snowfall ones is true, of course. Link to comment Share on other sites More sharing options...
clskinsfan Posted March 4, 2013 Share Posted March 4, 2013 GFS crushing almost all of VA at 39. Link to comment Share on other sites More sharing options...
blazeKing Posted March 4, 2013 Share Posted March 4, 2013 Gfs looks about the same thru 39 .. low slightly south and slower , still kinda warmish Link to comment Share on other sites More sharing options...
TL97 Posted March 4, 2013 Share Posted March 4, 2013 DC at 1 inch at 48 on the GFS Link to comment Share on other sites More sharing options...
stormtracker Posted March 4, 2013 Author Share Posted March 4, 2013 Gfs looks about the same thru 39 .. low slightly south and slower , still kinda warmish You have the soundings already? Link to comment Share on other sites More sharing options...
Ian Posted March 4, 2013 Share Posted March 4, 2013 It spells out they aren't highly confident on full totals think it might be more that the timeframe is too far out for their zone products to have numbers but still stupid and confusing Link to comment Share on other sites More sharing options...
stormtracker Posted March 4, 2013 Author Share Posted March 4, 2013 Rapid 850 crash after 45 hour Link to comment Share on other sites More sharing options...
TL97 Posted March 4, 2013 Share Posted March 4, 2013 DC at 1.5+ at 54, Baltimore at 1 in. Link to comment Share on other sites More sharing options...
mitchnick Posted March 4, 2013 Share Posted March 4, 2013 nasty dry slot at 45 hrs Link to comment Share on other sites More sharing options...
blazeKing Posted March 4, 2013 Share Posted March 4, 2013 You have the soundings already? just compare the 18z to 12z it does look slightly warmer, not much though, it still goes away once the heavy precip starts Link to comment Share on other sites More sharing options...
Ian Posted March 4, 2013 Share Posted March 4, 2013 oof my snow maps look terrible for dc Link to comment Share on other sites More sharing options...
MN Transplant Posted March 4, 2013 Share Posted March 4, 2013 Gfs looks about the same thru 39 .. low slightly south and slower , still kinda warmish Not kinda warmish, really really warm. Link to comment Share on other sites More sharing options...
WinterWxLuvr Posted March 4, 2013 Share Posted March 4, 2013 For those flipping out over snow maps, the better ones over at wxcaster have the 12" line running right through DC. Not that it means much, but I thought it might make some feel better. Link to comment Share on other sites More sharing options...
yoda Posted March 4, 2013 Share Posted March 4, 2013 48 h5 is a beaut.. well placed Link to comment Share on other sites More sharing options...
Ian Posted March 4, 2013 Share Posted March 4, 2013 oof my snow maps look terrible for dc some redemption post 0z thurs but cut way back compared to prior Link to comment Share on other sites More sharing options...
stormtracker Posted March 4, 2013 Author Share Posted March 4, 2013 Not kinda warmish, really really warm. Cools after 45 though? Link to comment Share on other sites More sharing options...
MN Transplant Posted March 4, 2013 Share Posted March 4, 2013 Cools after 45 though? No, this is the nightmare run. All rain immediate DC metro during daylight hours Wednesday. Link to comment Share on other sites More sharing options...
Ji Posted March 4, 2013 Share Posted March 4, 2013 i think im ready for the N/W trend to stop Link to comment Share on other sites More sharing options...
Ji Posted March 4, 2013 Share Posted March 4, 2013 Im taking a road trip to Leesburg Link to comment Share on other sites More sharing options...
Ian Posted March 4, 2013 Share Posted March 4, 2013 No, this is the nightmare run. All rain immediate DC metro during daylight hours Wednesday. yeah it blows next Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.