Roger Smith

The table is how much more snow you need, so it's consistent with your forecast as you quoted it.

Thunder-frozen possible from I-95 northwestward (in MD) and north of an east-west vector from Dale City (in VA). Most likely MoCo to Baltimore county.

Still looks like it would not take much pressure from the cold air to force a center jump from CRW to se DCA and allow wintry precip to continue in much of this region. It's a steadily deepening low which is good in that the energy will force cold air to flow into the CAD zone. My gut says 1-2" snow followed by sleet, non-accum zr, then back to sleet and a top off of 0.5" snow in a final plunge. SBY could hit 60 while BWI and DCA remain 35-40, IAD 32-35 F. Some thunder with all of the above. While it could have been so much better, at least it's interesting.

I updated the table of snowfalls required from amounts reported in this recent event (0.9" BWI, 1.0" DCA, 1.8" IAD). The table is back a page now, here's the amounts still required in much reduced print size if you want to see them right away. Note, I backed this work up with an excel file, the only possible source of error now would be if I have entered anyone's predictions incorrectly. SNOWFALL CONTEST AMOUNTS STILL REQUIRED (entries in brackets = amounts now in excess of season to date) Forecaster _____ Nov date _____ BWI ___ DCA ___ IAD ___ RIC _____ Total dep Snow to date __ 18 Jan ____ 9.2 ___ 12.7 ___ 15.4 __ 13.0 EastCoastNPZ ______ 22 _______ 1.7 ___ (6.2) ___ (4.3) __ (4.3) _____ 16.5 Bristow Wx _________ 1 _______ 4.6 ___ (6.0) ___ (2.8) __ (4.3) _____ 17.7 MN Transplant _____ 28 _______ 8.6 ___ 1.5 _____ 4.2 ___ (5.2) _____ 19.5 supernovasky _______ 9 _______10.8 ___ (1.7) ___ 3.6 ___ (4.0) _____ 20.1 RodneyS __________ 21 ______ 11.1 ___ 1.2 ____ 8.2 ____ 0.3 ______ 20.8 biodhokie __________ 8 ______ 12.1 ___ 5.1 ____ 2.7 ____ 1.5 ______ 21.4 leesburg 04 _________1 ______ 12.8 ___(0.7)____ 7.6 ____(2.0) _____ 23.1 Weather53 _________21 _____ 12.0 ___ 3.8 ____ 6.7 ____ 1.7 ______ 24.2 Olafminesaw _______25 ______ 10.2 ___ 4.6 ____ 8.1 ____(3.2) _____ 26.1 Stormpc ___________26 ______10.7 ___ 4.0 ____ 9.2 ____ 4.2 ______ 28.1 nw Baltimore wx ___ 10 ______ 12.8 ___ 3.3 ____ 9.6 ____(5.0) _____ 30.7 Bob Chill __________ 27 ______ 16.8 ___ 3.3 ___ 13.6 ____ 1.0 ______ 34.7 Prince Frederick Wx _ 1 _______ 15.3 ___ 5.0 ___ 12.4 ____ 4.1 ______ 36.8 WinterWxLuvr ______ 8 ______ 13.8 ___ 5.3 ___ 16.6 ____ (2.0) _____ 37.7 dmillz25 ____________1 ______ 19.8 ___ 6.3 ____ 9.6 ____(2.0) _____ 37.7 Chris78 ____________ 1 ______ 17.5 ___ 5.7 ___ 13.2 ____ 1.9 ______ 38.3 Thanatos_I_Am ____ 30 ______ 18.4 ___ 5.6 ___ 10.4 ____ (5.5) _____ 39.9 Grothar of Herndon _ 30 ______ 16.5 ___ 5.6 ___ 13.7 ____ 6.2 ______ 42.0 MillvilleWx __________1 ______ 18.2 ___ 8.4 ___ 14.1 ____ 2.0 ______ 42.7 cae ______________ 30 ______ 18.4 ___ 9.1 ___ 15.9 ____(0.3)______ 43.7 Gopper ___________ 15 ______ 19.6 ___ 5.0 ___ 17.9 ____ 2.5 ______ 45.0 Gramax Refugee ____27 ______ 20.3 ___ 4.2 ___ 16.6 ____ 4.2 ______ 45.3 Wonderdog ________ 9 _______17.8 ___ 3.3 ___ 17.6 ____ 7.0 ______ 45.7 NorthArlington101 ___ 1 ______ 16.5 ___10.1 ___ 16.8 ____ 3.0 ______ 46.4 Yoda _____________ 27 ______ 20.4___ 9.1 ___ 17.5 ____ 1.1 ______ 48.1 WxWatcher007 _____30 ______ 19.7 ___ 8.4 ___ 17.1 ____ 3.4 ______ 48.6 mattie g __________ 28 ______ 21.4 ___ 8.4 ___ 23.3 ____ 0.9 ______ 54.0 Prestige Worldwide __27 ______ 21.8___10.3 ___ 19.6 ____ 2.8 ______ 54.5 North Balti Zen ______5 ______ 19.6 ___ 8.4 ___ 20.3 ____ 6.6 ______ 54.9 ___ Consensus ____ median ___ 21.4___10.0 ___ 19.6 ____ 4.0 ______ 55.0 Shadowzone _______ 14 ______ 22.5___11.4 ___ 20.3 ____ 3.8 ______ 58.0 LP08 ______________ 5 ______ 25.2 ___ 7.0 ___ 27.2 ____ 0.3 ______ 59.7 WxUSAF ___________ 5 ______ 22.3 ___10.0 ___ 19.8 ____ 8.1 _____ 60.2 mappy _____________5 ______ 22.8___12.3 ___ 19.6 ____ 6.0 ______ 60.7 George BM ________ 15 ______ (7.5) __(11.3) __ (12.4) __ 29.7 _____ 60.9 Sparky ____________ 2 ______ 24.8___12.3 ___ 23.6 ____ 1.0 ______ 61.7 BTRwx'sThanksGiving_12 _____ 24.8___11.3 ___ 22.6 ____ 4.0 ______ 62.7 T. August _________ 21 ______ 26.8___10.2 ___ 12.1 ____16.2______ 65.3 Cobalt ____________ 30 ______ 24.0___14.2 ___ 24.0 ____ 3.8 ______ 66.0 clskinsfan _________ 20 ^ 1 ___28.3___14.8 ___ 21.1 ____ 5.5 ______ 69.7 OnceinaLifetime2009_ 28 ______20.9___14.0 ___ 29.1 ____ 6.9 ______ 70.9 HighStakes _________ 6 ______ 28.2___11.8 ___ 25.7 ____ 7.0 ______ 72.7 ravensrule _________12 ______ 28.8___17.3 ___ 24.6 ____ 2.0 ______ 72.7 psuhoffman ________ 1 ______ 29.8___15.3 ___ 21.6 ____ 7.0 ______ 73.7 C. A. P. E. __________1 ______ 29.3___17.6 ___ 20.4 ____ 7.1 ______ 74.4 Roger Smith _______ 26 ^ 1___ 34.6___16.5 ___ 27.1 ____ 8.0 ______ 86.2 JakkelWx _________ 30 ______ 30.8___22.3 ___ 26.6 ___ 11.0 ______ 90.7 GATECH __________ 1 _______ 35.7___23.0 ___ 32.1 ____ 1.3 ______ 92.1 southMDwatcher ___ 20 _______34.6___18.4 ___ 32.5 ____ 7.7 ______ 93.2 budice2002 _______ 14 ______ 32.8___18.3 ___ 30.6 ____13.0 ______ 94.7 weatherCCB _______ 16 ______ 37.6___14.7 ___ 34.2 ____10.0 ______ 96.5 snowgolfbro _______ 10 ______ 37.8___17.3 ___ 36.6 ____ 5.0 ______ 96.7 nj2va _____________ 1 _______39.5___16.5 ___ 44.5 ____ 5.9 ______106.4 SnowLuvrDude _____30 ______ 39.4___24.4 ___ 37.0 ____ 8.7 ______109.5 showmethesnow ___ 27 ______ 40.8___21.3 ___ 38.6 ___ 11.0 ______ 111.7 tplbge ____________16 _______43.8___21.3 ___ 33.6 ___ 16.0 ______114.7 wxdude64 ________ 13 _______46.6___25.7 ___ 42.0 ___ 13.1 ______127.4 osfan24 ___________ 7 _______45.1 __33.5 ___ 40.5 ___ 18.3 ______ 137.4 AFewUnivBelowN ___ 1 _______55.8 __27.3 ___ 40.6 ___ 15.0 ______ 138.7 RIC Airport ________ 1 _______53.3 __33.3 ___ 46.5 ___ 19.2 ______ 152.3 __________________________________________________________

Euro not very encouraging but you never know with these lows moving southeast away from the Rockies, they can stay wide and come up the coast. Thursday's overperforming snow might be a tip that cold is not giving up without a fight. Would see if 12z model runs start to show a coastal trend.

AIRPORTS: IAD 1.5" __ DCA 1.0" __ BWI 0.6" (to midnight)

A clipper a day keeps the snow drought away.

Southward trends as models come more in line with fantasy forecast ... still not sure if this can get all the way to an all or mostly snow outcome but models have at least realized what was fairly obvious yesterday, this low was not likely to suck up a lot of warm air with that lurching trough and a frigid Canadian high pushing down, nor was it ever going to see the sights of Pittsburgh, Scranton or Springfield, MA. Looks like one of those early spring lows that never advects warm air and gets hammered from all sides by cold air with an explosion of thunder-sleet, ice pellets, and winds backing around the compass for hours.

They will get a good cover from all the snow falling off vehicles turned around at the Donner Pass.

That is one ugly baby.

Mid-Atlantic weather crew's greatest hits ... "Once in a lifetime (jet stream flowing under) ... Once in a lifetime (snow drifts getting bigger) ... and you may ask where is my cold air damming? and you may ask where are my cold 850s? (same as it ever was) (same as it ever was) ..."

Oh great, that should add a few hundred feet to the inversion cloud layer above my head then. Here's a schematic ... ^ ^^^ - - - - - - - - 10 deg C ^^^^^^ %@%@%@%@%@% cloud @%@%@%@%@% ^^^^^ ^^^^^^^^^^^ ------------- drizzle ----------- drizzle ---- ^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^^ moi ^^^^^^^^^^^^^^^^^

These would be my reasons for optimism, but even so I would currently say 30% chance of 5" snowfall as far south as I-95. A lot of things have to go right to get this to be a mostly snow event in this area. First thing would be for the leading wave to drop 1-3" snow over the bare ground between your fading snow pack and the more permanent one further north. Second good sign is that the weekend low will form out of the base of another Pacific low swerving north, so is not going to be subject to easy modelling for several days yet. Looking west, there is remnant snow cover from the last event to weaken warm air advection into the plains states. Every degree south we can find this low forming over OK-AR the better your chances. Third positive thought is that another potent arctic high is coming into play for the weekend storm and each model I looked at seems to respond a bit sluggishly to the possibility of cold air building up over PA-NJ into the mid-Atlantic region in advance of the storm. Old school, one would draw the arctic front quite a bit further south than the 0 C 850 isotherm which tells me that this weekend storm could be running into some well-entrenched colder air. Fourth good sign is the steady deepening trend for central pressure after the low reaches TN. A steadily deepening low will continue to pull in the cold air on the east side of the mountains until it reaches south-central VA. This should allow some early portion of the precip to be snow. If we can find (I don't like to say get because that's a bogus process) -- if we can find this low just edging south of the model tracks, continuing to deepen nicely, then it could drop 8-12 inches of snow at least north of I-95. A lot of things have to go right. But then they all did last weekend.

I will post optimistic thoughts in the new thread. But this weekend storm is more likely to shift south than north given all the variables in play.

All you need at this point is for more robust cold air intrusion between the weak Friday system and the stronger Sunday-Monday low, and with the track that seems to be emerging, the event could become largely wintry at least from I-95 north. Each model I look at invites a second look with that more robust cold air setting itself in front of the depicted track, which itself would likely be pushed slightly south if that cold air did make its move. Probably about a 30% chance of the event being a significant snowstorm for DC and BAL. Same general idea in play for PHL, NYC and BOS also, the track is only just on the wrong side of them too.

Okay, that's because I corrected a few errors, you were right but it was all my math that created them. Just about done checking using a calculator so it should be good. If we get more snow later, I will check those against a calculator instead of trying to do them in my head. Found a few that were just slightly off so the order in my table was still okay. Thanks for looking.

Okay, will check it out, starting with Leesburg04. Send me a PM just names if you have a moment, I can check it faster if I know where to look. Have checked your top ten and fixed leesburg04 and a small error for biodhokie which did not affect placement in the table (0.3 error). Both of these errors were in my math in the departures and not in the raw data entry so I haven't found anything to edit yet in the basic tables, just that last one I worked out. But if you're aware of any other errors, let me know. I am going back over the basic data entry first before I check the standings table that I published.

Continued reports on anomalies and forecasts ... ______________________ DCA _ NYC _ BOS __ ORD _ ATL _ IAH __ DEN _ PHX _ SEA _8th ___ (7d) __________+10.2_ +7.1_ +7.6 _+12.0_+12.5 _+1.8 __+2.7 _--6.2 _+2.7 15th __ (14d) __________ +5.5_ +3.1_ +3.9 __ +6.9_ +6.9 _+1.5 __+2.9 _--2.1 _+4.1 22nd __ (21d) __________+2.9_ +0.9_ +2.1 __ +4.3_ +4.8 _+1.1 __+4.2 _--0.6 _+3.8 25th __ (24d) __________ +2.8_ +1.4_ +2.4 __ +3.3_ +4.4 _+1.1 __+2.8 _--1.1 _+3.6 ((*)) 29th __ (28d) __________ +2.4_ +1.3_ +2.7 __ +0.3_ +3.5 _+0.9 __+1.8 _--0.9 _+3.6 _8th ___ (p14d) _________+4.5_ +2.5_ +2.8 __ +6.0 _+5.8 _+2.0 __+5.0 _--1.6 _+2.5 15th ___ (p21d) _________+3.5_ +1.2_ +1.8 __ +3.8_ +5.0 __0.0 __ +2.3 _--1.0 _+2.7 22nd ___ (p28d) ________ +2.0_ +0.1_ +0.5 __ +0.8_ +2.0 _--1.0 __ +2.8 _+0.5 _+3.1 _8th ___ (p24d) _________+1.5_ +0.5_ +0.5 __ +2.0 _ +2.0 _+2.0 __ +1.5 _--2.0 _+1.5 ((*)) 15th ___ (p31d) _________+0.5_--1.5_ --1.0 ____ 0.0 _ +2.0 _--1.5 __--1.5 _--1.7 _+0.5 22nd ___ (p31d) ________ +0.5_--0.5_ --0.5 ____ 0.0 _ +1.0 _--1.5 __ +2.0 _+0.5 _+4.0 29th ___ (p31d) _________+1.5_ +0.5_ +2.0 ___--2.5 _+2.0 __0.0 __ +1.5 _--0.5 _+3.0 31st __ final anomalies ___ +1.2_ --0.1_ +1.8 ___--2.8_ +2.6 _+0.3 __+1.3 _--0.4 _+3.0 ____________________________________________________________ 15th _ The expected cooling trend was reasonably well predicted with an average error of 1.04 deg. The coming week will see most locations falling slowly at first and then much faster from their current positive anomalies. Then the GFS advertises very cold anomalies for most locations after 21st, and this should begin to turn some of the positives to negatives before the month ends. 22nd _ The faster cooling trend in the past seven days was well handled except at DEN and SEA which warmed more than expected. The next seven days will be a collection of very cold days with milder than average intrusions, making the reliability of the seven-day (and therefore end of month) outlooks a bit subject to change, then the last three days look very cold in the east, cold to milder further west. SEA should hold on to a large positive anomaly which will be good news for DonS if I am reading the charts right. Provisional scoring will follow later today, based on the new end of month figures. 25th _ The 16d forecast from 8th is verified today ((*)) rows can be compared. The average error is 1.5 deg and the score for the "forecast" would be 640, about the same as our consensus from the first, so no improvement and similar numbers to our consensus. I have not updated end of month because it seems that if the cold is extreme the numbers will verify and if not some locations will come in higher by 0.5 to 1.0, so I will revisit this on 29th. 29th _ Got to this task very late so I have the anomalies for the 29th as well. The forecasts from 22nd were generally too cold in the east and too warm in the west, so changes in the end of month are mostly due to that fact rather than anything unexpected from today to Thursday. Chicago will plummet with record cold on top of the severe cold they've had all week, and the eastern cities will only get a glancing blow, so those numbers are going to change substantially. The western three will all come in a bit colder than earlier forecast, I think. Scores will be adjusted soon. 31st _ 1st overnight __ updating anomalies and scoring __ no big surprises except that IAH already reported, usually they are last in.

SBY now updated too, 3.7" storm for 4.5" seasonal. LYH had already posted 4.1" for 15.6" seasonal. My charts showing the graphic version of the contest standings are updated. Hoping that my calculations are accurate, I did come up with the same leader anyway.

It looks cold but in Feb 1934 there were readings of -50 F in upstate New York and eastern Ontario, and Lake Ontario froze over completely. Also in Jan 1976 I was living close to where you see that -14 reading east of Georgian Bay and it was -42 F overnight. The readings north of Lake Superior are probably close to all-time records on that map though. There is very little ice on the Great Lakes so far this mild winter (until last few days), Canadian govt not shut down so I could refer you to the ice cover maps on the EC site. But only small amounts of ice showing near shore on the GL.

Thanks, it just changed for RIC on the daily climate report as you say, 13.0 with 1.5 this month but the CF6 still shows missing amounts for 12th and 13th under snowfall. I will edit tables and charts after they confirm on the CF6, as I am not sure if this 1.5" includes all the weekend time period or only a part of it. Will make no difference to the order I have listed there since almost everyone has 0.5" left to use up but it will move the leaders 1.0" closer to their chasers if they have gone over their forecast amounts for RIC. Also my charts are totally unofficial, just for something to look at until the official stats are posted by PFwx. edit __ I have updated now using the 13.0" total.

In the meantime, I have edited those charts that I posted earlier (the DCA centered one is two posts back, the RIC centered one is edit back further) ... the only unknown at this point is SBY, as I have an update of 1.5" for RIC and have now confirmed 3.7" for SBY for a seasonal total of 4.5" (LYH is 15.8" seasonal) -- will continue to edit those charts with updated information as it comes in. But I think participants may be interested in this, it's a table of what you are now forecasting to reach your targets (and in a very few cases, departures from already passed forecasts). This will approximate what the official contest report says in a day or two about the new order of merit, as I arranged these in terms of total departures. So this is how much more snow you need to get to a perfect forecast (excluding those few who have built in errors already). I have not included the tie breakers in this table. (As of March 8th, SBY now 5.3" and LYH now 21.0"). SNOWFALL CONTEST AMOUNTS STILL REQUIRED (entries in brackets = forecasts now in excess of season to date) Forecaster _____ Nov date _____ BWI ___ DCA ___ IAD ___ RIC _____ Total dep Snow to date __ MAR 8 _____ 18.2 __ 16.9 __ 26.5 __ 13.1 Stormpc ___________26 _______ 1.7 ___(0.2) ___ (1.9) ___ 4.1 ______ 7.9 Olafminesaw _______ 25 _______ 1.2 ___ 0.4 ____(3.0) ___(3.3) ______7.9 RodneyS __________ 21 _______ 2.1 ___(3.0)___ (2.9) ____ 0.2 ______8.2 Weather53 _________21 ______ 3.0 ___(0.4)___ (4.4) ____ 1.6 ______ 9.4 nw Baltimore wx ___ 10 _______ 3.8 ___ (0.9) ___(1.5)___ (5.1) _____ 11.3 Bob Chill __________ 27 _______ 7.8 ___ (0.9) ___ 2.5 ____ 0.9 ______ 12.1 Prince Frederick Wx __1 ________6.3 ___ 0.8 ____ 1.3 ____ 4.0 ______ 12.4 WinterWxLuvr ______ 8 ________4.8 ___ 1.1 ____ 5.5 ____ (2.1) _____ 13.5 biodhokie __________ 8 _______ 3.1 ___ 0.9 ____ (8.4) ___ 1.4 ______ 13.8 Chris78 ____________ 1 _______ 8.5 ___ 1.5 ____ 2.1 ____ 1.8 ______ 13.9 leesburg 04 _________1 _______ 3.8 ___ (4.9)____(3.5) ___(2.1) _____ 14.3 MN Transplant _____ 28 _______ (0.4) ___(2.7)___(6.9) ___ (5.3) _____ 15.3 dmillz25 ____________1 ______ 10.8 ___ 2.1 ____(1.5)____(2.1) _____ 16.5 Thanatos_I_Am ____ 30 _______ 9.4 ___ 1.4 ____(0.7)____ (5.6) _____ 17.1 Grothar of Herndon _ 30 _______ 7.5 ___ 1.4 ____ 2.6 ____ 6.1 ______ 17.6 MillvilleWx __________1 _______ 9.2 ___ 4.2 ____ 3.0 ____ 1.9 ______ 18.3 supernovasky _______ 9 _______ 1.8 ___ (5.9) ___(7.5) ___(4.1) _____ 19.3 cae ______________ 30 _______ 9.4 ___ 4.9 ____ 4.8 ____(0.4)______ 19.5 Gopper ___________ 15 ______ 10.6 ___ 0.8 ____ 6.8 ____ 2.4 ______ 20.6 Gramax Refugee ____27 ______ 11.3 ___ 0.0 ____ 5.5 ____ 4.1 ______ 20.9 NorthArlington101 ___ 1 _______ 7.5 ___ 5.9 ____ 5.7 ____ 2.9 ______ 22.0 Wonderdog ________ 9 ________8.8 ___(0.3)____ 6.5 ____ 6.9 ______ 22.5 Yoda _____________ 27 ______ 11.4 ___ 4.9 ____ 6.4 ____ 1.0 ______ 23.7 WxWatcher007 _____30 ______ 10.7 ___ 4.2 ____ 6.0 ____ 3.3 ______ 24.2 mattie g __________ 28 ______ 12.4 ___ 4.2 ___ 12.2 ____ 0.8 ______ 29.6 Prestige Worldwide __27 ______ 12.8___ 6.1 ____ 8.5 ____ 2.7 ______ 30.1 North Balti Zen ______5 ______ 10.6 ___ 4.2 ____ 9.2 ____ 6.5 ______ 30.5 ___ Consensus ____ median ___ 12.4___ 5.8 ____ 8.5 ____ 3.9 ______ 30.6 Bristow Wx _________ 1 ______ (4.4) _ (10.2) __(13.9) ___(4.4) _____ 32.9 Shadowzone _______ 14 ______ 13.5___ 7.2 ____ 9.2 ____ 3.7 ______ 33.6 LP08 ______________ 5 ______ 16.2 ___ 2.8 ___ 16.1 ____ 0.2 ______ 35.3 wxUSAF ___________ 5 ______ 13.3 ___ 5.8 ____ 8.7 ____ 8.0 ______ 35.8 mappy _____________5 ______ 13.8___ 8.1 ____ 8.5 ____ 5.9 ______ 36.3 Sparky ____________ 2 ______ 15.8___ 8.1 ___ 12.5 ____ 0.9 ______ 37.3 EastCoastNPZ ______ 22 _____ (7.3) __(10.4) __(15.4) ___(4.4) _____ 37.5 BTRwx'sThanksGiving_12 _____ 15.8___ 7.1 ___ 11.5 ____ 3.9 ______ 38.3 T. August _________ 21 ______ 17.8___ 6.0 ____ 1.0 ____16.1______ 40.9 Cobalt ____________ 30 ______ 15.0___10.0 ___12.9 ____ 3.7 ______ 41.6 clskinsfan _________ 20 ^ 1 ___19.3___10.6 ___ 10.0 ____ 5.4 ______ 45.3 OnceinaLifetime2009_ 28 ______11.9___ 9.8 ___ 18.0 ____ 6.8 ______ 46.5 HighStakes _________ 6 ______ 19.2___ 7.6 ___ 14.6 ____ 6.9 ______ 48.3 ravensrule _________12 ______ 19.8___13.1 ___ 13.5 ____ 1.9 ______ 48.3 psuhoffman ________ 1 ______ 20.8___11.1 ___ 10.5 ____ 6.9 ______ 49.3 C. A. P. E. __________1 ______ 20.3___13.4 ____ 9.3 ____ 7.0 ______ 50.0 Roger Smith _______ 26 ^ 1___ 25.6___12.3 ___ 16.0 ____ 7.9 ______ 61.8 JakkelWx _________ 30 ______ 21.8___18.1 ___ 15.5 ___ 10.9 ______ 66.3 GATECH __________ 1 _______ 27.7___18.8 ___ 21.0 ____ 1.2 ______ 67.7 southMDwatcher ___ 20 _______25.6___14.2 ___ 21.4 ____ 7.6 ______ 68.8 budice2002 _______ 14 ______ 23.8___14.1 ___ 19.5 ____12.9 ______ 70.3 weatherCCB _______ 16 ______ 28.6___10.5 ___ 23.1 ____ 9.9 ______ 72.1 snowgolfbro _______ 10 ______ 28.8___13.1 ___ 25.5 ____ 4.9 ______ 72.3 nj2va _____________ 1 _______30.5___12.3 ___ 33.4 ____ 5.8 ______ 82.0 George BM ________ 15 _____ (16.5) __(15.5) __ (23.5) __ 29.6 _____ 85.1 SnowLuvrDude _____30 ______ 30.4___20.2 ___ 25.9 ____ 8.6 ______ 85.1 showmethesnow ___ 27 ______ 31.8___17.1 ___ 27.5 ___ 10.9 ______ 87.3 tplbge ____________16 _______34.8___17.1 ___ 22.5 ___ 15.9 ______ 90.3 wxdude64 ________ 13 _______37.6___21.5 ___ 30.9 ___ 13.0 ______103.0 osfan24 ___________ 7 _______36.1 __29.3 ___ 29.4 ___ 18.2 ______ 113.0 AFewUnivBelowN ___ 1 _______46.8 __23.1 ___ 29.5 ___ 14.9 ______ 114.3 RIC Airport ________ 1 _______44.3 __29.1 ___ 35.4 ___ 19.1 ______ 127.9 __________________________________________________________

I think that the relationship between snow cover and cyclone tracks is largely a manifestation of persistence rather than forcing. The southerly extent of snow cover is likely to be similar to the track of previous cyclones. So if persistence is the best forecasting random element then the next cyclone should run along the snow boundary too, except that a snowfall event is more likely than not to be followed by cold air which would be statistically linked to falling heights, so therefore at random the next cyclone should run further south than the first snow-producer did. In actual fact I think there is almost no forcing mechanism from event to event. If other factors realign the upper level flow, then a low will just charge into the snow cover zone and rain on it, and the only feedback will be in terms of slight downward pressure on air mass temperatures in the warm sector. Also in this case, you have two distinct snow boundaries so the next major system could choose either one to verify the theory (one being south of your region and one being around upstate NY into south-central ON). In this particular case, I have a hunch that there will be a last-minute trend south on the main event after the leading wave is followed by a sagging frontal boundary and the strong high clamps down on the energy. Not 100% confident that you'll be in the sweet spot, perhaps more like s PA, but in with a chance for 5-10" anyway. The harsh temperature drop seems realistic for any who do get into the warm sector.

If highs are in the 38-43 F range I would expect you would lose about 2" a day mostly to sublimation (loss into the air as water vapor). As I mentioned before the storm, we had a similar snowfall here last Wednesday that was unrelated to your storm except it happened at a similar temperature and we've had those sorts of temperatures since, and I still have full snow cover of about 2-3" here today. If it gets much above 43 F though, it's going to disappear in two or three days or so except in deeper shade. Since there's some chance of a top-up on Friday, I would expect you will get to that event with half your snow pack intact, and of course all large snow piles will start melting down a bit, but those will last until there's three or four very mild days and/or some heavy rain.

I knew if I hung in long enough, I could under-predict a Mid-Atlantic snowfall. It almost happened in 2010 but now it has. We move on to the second sign of the apocalypse.