Roger Smith

Snowfalls to date -- to May 9, 2019 -- this post will be updated whenever new snow is reported ... LOCATION _______ Oct __Nov __Dec __Jan _ Feb _Mar _Apr+May Contest total __ % Normal (full season) APN ______________ 0.2__11.2 __11.5__33.6 __24.7__ 8.1 __10.1 ____ 99.4 _______ 124 ORD ______________ Tr __12.7 __ 1.4 __18.2 __ 9.0 __ 0.3 __ 7.9 ____49.5 _______ 130 CLE _______________0.0 __ 4.4 __ 2.8 __16.0 __ 5.4 __ 6.6 __ 0.0 ____35.2 ________ 52 CMH ______________0.0 __ 2.1 __ 0.4 __11.3__11.6 __ 2.0 __ 0.0 ____ 27.4 ________ 96 DTW ______________ Tr __ 6.7 __ 0.5 __14.2 __ 7.3 __ 2.6 __ 0.0 ____ 31.3 ________ 70 FWA ______________0.0 __ 2.1 __ 0.1 __14.3 __ 5.4 __ 2.7 __ 0.1 ____ 24.7 ________ 73 GRR ______________ Tr __14.4 __ 3.2 __30.5__ 20.4 __ 7.9 __ 4.9 ____ 81.3 _______105 GRB ______________ Tr __ 3.8 __ 8.1 __22.7 __ 28.4 __ 6.5 __ 4.5 ____ 74.0 _______137 IND _______________Tr __ 0.4 __ 0.5 __ 11.7 __ 4.5 __ 2.3 __ 0.0 ____ 19.4 ________ 75 LSE ______________ 0.1 __ 1.9 __ 4.0 __15.1__ 31.1 __ 5.9 __ 6.2 ____ 64.3 _______ 139 YXU ______________ 0.0 __ 3.2 __ 2.0 __16.0 __ 9.4 __ 2.8 __ 0.6 ____ 34.0 ______ 45 SDF ______________ 0.0 __ 0.5 __ Tr ___ 7.5 __ 0.6 __ 2.6 __ 0.0 ____ 11.2 _________81 MQT ______________4.2 _ 37.7 _ 39.0 __34.1 _ 89.9 __ 8.2 __ 8.6+5.8_227.5 ____ 114 MKE ______________ Tr __ 6.6 __ 1.5 __20.2 __18.7 __ 1.6 __ 7.5 ____ 56.1 ________ 114 MSP ______________0.3 __ 4.0 __ 6.7 __ 6.8 __39.0 __10.5 __ 9.8 ____ 77.1 _______ 151 MLI ______________ 0.2 _ 18.4 __ 1.1 __30.2 __ 8.8 __ 2.1 __ 0.0 ____ 60.8 ________ 181 PAH ______________0.0 __ 2.3 __ Tr ___ 3.2 __ 0.3 __ 0.3 __ 0.0 _____ 6.1 _________ 66 PIA _______________Tr __ 9.8 __ 0.4 __17.9 __ 2.5 __ 0.8 __ 5.0 ____ 36.4 _________146 STL ______________0.0 __ 5.2 __ 1.7 __12.5 __ 2.4 __ 2.4 __ 0.0 ____ 24.2 _________132 YYZ ______________1.0 __ 6.2 __ 2.2 __24.9 __17.3 __ 3.3 __0.2 ____ 55.1 _________130 ________ _______ _______ _______ _______ _______ _______ _______ _______ _______ Total _____________________________________________________ 1094.6 _____ 108.0% _____________________________________________________________________________ _ All locations updated to May 2nd. ORD had 2.5" MKE 1.7" and LSE 0.3" on Apr 27th, YYZ 0.1" on 29th and MQT 5.4" on May 1st and 0.4" May 7-9. ... Canadian locations are converted to inches from cms. ... LSE and GRB became 6th and 7th locations to pass contest average on 20th. MSP is now the 8th and MQT the 9th station to pass 1986-2015 contest averages. ... APN surpassed seasonal average but the addition came from a revised November total. That makes ten stations above contest average now. ... MKE edged past contest normal on April 10th. GRR reached contest normal on April 11th and passed it on the 14th. ... CMH is within 4% of seasonal average but is running out of time to increase. ... The least snow relative to normal has fallen at YXU (45%) and CLE (52%). ... The remaining five locations (DTW, FWA, IND, SDF, PAH) are in the 66 to 81 per cent range. TOTAL SNOWFALL PASSED THE CONTEST NORMAL VALUE ON MARCH 30th.

Still thinking that we are entering the best part of the winter for eastern states, one or more of these energy peaks seems likely to deliver good snowstorm events: Feb 2-4, Feb 12-15 and/or Feb 17-20. The predecessor events in the series have tracked mostly inland and delivered to regions like the eastern Great Lakes, interior New England, central PA, Ohio. With a bit of retrograde influence peaking in early to mid February, expect the storm track to loop further south ending up closer to the east coast. I am holding to my earlier prediction that a warm trend would then quickly develop into March and that March-April might be well above normal in temperature in many parts of eastern and central NA.

From a different research perspective I am expecting a peak in retrogression and blocking in mid-February. Is there any chance that the MJO index has some correlation to externally driven factors? I have not had much time to investigate this, but the retrograde index that I use has periods like 90 and 120 days (won't say more precisely what they are outside a research paper). And is the MJO a retrograde feature or random in its movements relative to longitude? I have thought all along that this would be a difficult winter to forecast because of the competing influences of El Nino (a warming influence) and the combination of low solar and prior negative anomaly buildups in a source region (central arctic of Canada). Rather like saying your football team has a strong offence and almost no defence, will you be favored to win or lose?

Reality has passed the following numbers of forecasts: BWI _ 1 forecast surpassed. DCA _ 5 forecasts surpassed. IAD _ 3 forecasts surpassed. RIC _ 12 forecasts surpassed. and I think SBY has passed one of 55 who chose it, LYH has not passed any of its three forecasts.

After the widespread snowfalls of the past few days, the contest grid has now passed the 40% mark (table is back in the thread, first posted Dec 17th and edited up to date). STL has passed its average for 1986-2015. MQT has roughly one quarter of all the snow recorded and is a little over half of its seasonal average at 105" now. Plenty of snowfall opportunities appear on the charts so we should at least keep pace with normal snowfall for a while yet. I think that 40% on January 21st is probably a touch below average pace but not much, as February and March contribute at least 40% of a normal winter's snowfall and April perhaps 5%, so we should be at about 55% at the end of this month to be on a normal pace. That would only take 150" of snow over the 20-station grid or an average of 7.5" per location in the next ten days. The location doing worst so far is YXU sub Tillsonburg although they have yet to report the second half of the snowstorm and could go up from current 18% of normal. MSP and LSE are also in a snow drought relatively speaking in the low 20's for percentages. The highest performers behind STL (now at 103%) are MLI and PIA (both at 93%). That is largely because of their totals in November. (MLI took over the lead on Jan 23rd). Forecasts are generally still ahead of actuals, with a few exceptions for STL, MLI and PIA. But these are some of the error totals you now have locked in from those locations (updated for Jan 22nd snow at MLI, none reported at STL or PIA) ... this has changed as of Jan 23rd, see the scoring table two posts down for updated info as MLI added 5.9" and PIA 0.1" bringing in contest normal (MLI) and adding to all of these totals. The table below was valid after Jan 22nd but won't be updated. dmc76 _____ 7.7" __ (MLI and PIA, still 6.0" to give at STL) Jackstraw ___6.2" __ (PIA and STL) Stebo ______ 5.7" __ (PIA and MLI, almost caught at STL with 1.0" left to give) Roger Smith _4.5" __ (STL only) madwx _____ 2.8" __ (STL only) DAFF _______2.2" __ (STL only) DonSutherland 1.2" __ (MLI only) and the rest of the field are so far not into red numbers on any of these. ... The entire field have amounts left to use up everywhere else.

Best chances for thunder probably around 8 p.m. to 2 a.m. ahead of the low center which will be close to FDK around 0400h. A secondary peak will accompany the cold front mid-day Sunday.

Low is currently in w TN and track appears to be something like CRW to 50n FDK to PHL to ISP to BOS. There may be some eastward jogs in that overall e.n.e. to n.e. track. So I would expect some interesting weather to develop later because this is not advecting warm air very efficiently and when heavier precip moves in over top, it could change phase in some parts of MD and far n VA, ne WV. Not saying snow from that, more like ice pellets or sleet. Eventually it will begin to draw in the high 50s and low 60s temps from se VA but I think a very sharp demarcation of air masses will develop overnight so that some counties of se MD will reach 60-65 and the I-95 will stay around 40-45, further north 33-38. This is when precip could get quite thundery. When the low center reaches NYC the arctic cold front will be rushing southeast and temps on Sunday will likely fall 20-30 deg in a few hours, from those variable numbers in the warm sector and frontal zone, to 10-15 F. Some bursts of moderate snow are possible with the passage of the arctic front, 0.1 to 0.3 inch forecast for the airports and 1.0 inch for some parts of nw MD. So for the northern half of the forum it won't be a simple case of warming up, raining, and turning colder. For the southern half it may play out like that more so.

I don't want the UK I just want a KU, I don't want the Euro I just want a big snow, I don't want the RGEM, I just want a front end, I don't want the GFS, I just want these storms suppressed a little. a little. a little. a little.

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.