buckeyefan1

GSP .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 320 am EST Wednesday: The latest guidance suite is starting to feature a bit better agreement on the overall aspects of the winter storm likely to impact the area over the weekend. However, there remains some variation regarding low tracks, thermal profiles, and QPF for various periods, and these details continue to make precipitation types and amounts highly uncertain. Nearly all solutions have trended toward cutting off the southern portion of the split upper flow near the lower Mississippi River Valley by late Saturday. In a slight role reversal over the past 24 hours, the ECMWF 500 mb prognostic now features a cutoff low with a farther south low center position than the operational GFS. However, both models agree fairly well on the general timing, migrating the system over the Deep/Mid South Sunday and then over the Carolinas Sunday night as the system phases back into the northern stream. Meanwhile, sprawling surface high pressure from southern Ontario to New England will establish a strong cold air damming configuration east of the Appalachians ahead of the storm on Saturday. The resulting surface-based cold layer is becoming one of the more confident aspects of the upcoming weekend storm. The onset timing of wintry precipitation, however, remains uncertain. There are hints of weak and shallow upglide developing over the preexisting baroclinic zone as early as late Friday night or Saturday morning, with the isentropic lift slowly improving the day on Saturday well east of the approaching system. The forecast features below guidance temperatures and wintry ptypes at onset across the northern half. The period of deepest moisture and best forcing now looks slated for Saturday night through Sunday as a Deep South surface wave transitions to the Carolina coast. Strong jet-level divergence is indicated during this period and deformation zone forcing will likely impact our area by Sunday, especially over western NC given the current low track forecast. Precipitation types remain challenging. Profiles have trended to stronger warm nosing across the southern half of the area, with prolonged sleet and southern tier freezing rain now quite possible. However, the operational model runs appear warmer than most of the ensemble members, so much of the QPF could still fall as snow. An ensemble approach has been adopted for weekend profiles, which leads to more snow in the forecast than might be indicated on operational model profiles. The mixed ptype belt should especially impact locations southeast of I- 85, but with a changeover back to snow likely occurring from the west throughout on Sunday night as the system pulls away to the northeast. Scattered upslope snow showers should persist along the TN border counties through Sunday night, and possibly well into Monday, further enhancing snow amounts there. We are still a bit out of the Winter Storm Watch timeframe, so this will remain highlighted in the HWO. The main change will be the addition of sleet and freezing rain to the forecast, especially across the southeast part of the area. Another vigorous shortwave is forecast to drop southeast into the eastern trough Monday before the flow pattern flattens out by Tuesday. This could briefly reinvigorate western mountain snow showers, which may not have completely ended from the weekend system before this wave arrives. Upslope moisture will gradually end Monday night into Tuesday.

Not sure if this was posted overnight

Bless your trolling heart

fwiw the 06z nam was a touch weaker and a touch south too

The 06z euro looks the same as 0z, maybe a touch weaker

I've watched everyone around me for the past 4 years get in on some flake action, while I haven't even had the opportunity to go outside with my flashlight and black construction paper to search for a flizzard. All I want is to track a legit storm and make a snow angel The awesome part is that is happening and I'm so freaking excited!! Everyone just needs to take a breath, watch how it unfolds and enjoy the sleep deprivation as we move towards kick off

It would be no fun if there weren't different solutions every couple of hours . Anywho.....it seems as if I can't leave you all alone overnight without everyone cliff diving with each turn of the models. There is 4.5 days to go and 20 different ways this could all go down before it's showtime. Ya'll go outside and play today so when you come back to check the madness there won't be any whining and cliff diving. We are about to be in STORM MODE, so buckle up, keep the banter in the sanitarium and let's bring this beautiful winter wonderland for all of us home

fwiw 0z NAM is slightly weaker and a touch north of 18z

What we need to keep it from going too far north, is for the low pressure exiting stage right on Thursday to be stronger. That is the only difference on today's euro runs.

The 18z euro was about the same as 12z. It's a touch north and a hair stronger through 90

Bump @UpStateCAD The links are on the first page and I know the Tenn subforum has copied and added to this list through the years too.

I have so many I'll try to find the list we had posted for links and stuff. That I-85 struggle is real EDIT: Found it and bumped for everyone's viewing pleasure

It's a weatherbell graphic, but here's a good free site for buffkit/meteograms https://meteor.geol.iastate.edu/~ckarsten/bufkit/image_loader.phtml just put your airport code in the box to the right Here is their buffkit output for gsp(top) and the snow meteogram(below) 220116/0600Z 108 06011KT 32.8F RASN 0:1| 0.0|| 0.00|| 0.00|| 0.020 0:1| 0.0|| 0.00|| 0.00|| 0.02 79| 0| 21 ----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+--- 220116/0700Z 109 05013KT 30.5F SNPL 4:1| 0.3|| 0.04|| 0.00|| 0.065 4:1| 0.3|| 0.04|| 0.00|| 0.08 70| 30| 0 220116/0800Z 110 05015KT 29.4F SNPL 7:1| 0.4|| 0.04|| 0.00|| 0.057 6:1| 0.7|| 0.08|| 0.00|| 0.14 64| 36| 0 220116/0900Z 111 06015KT 28.5F SNOW 12:1| 1.1|| 0.00|| 0.00|| 0.093 8:1| 1.8|| 0.08|| 0.00|| 0.23 100| 0| 0 220116/1000Z 112 06015KT 27.6F SNOW 7:1| 0.9|| 0.00|| 0.00|| 0.129 8:1| 2.7|| 0.08|| 0.00|| 0.36 100| 0| 0 220116/1100Z 113 05016KT 26.7F SNOW 9:1| 1.2|| 0.00|| 0.00|| 0.133 8:1| 3.9|| 0.08|| 0.00|| 0.50 100| 0| 0 220116/1200Z 114 05017KT 25.8F SNPL 14:1| 2.0|| 0.04|| 0.00|| 0.149 9:1| 5.9|| 0.12|| 0.00|| 0.65 87| 13| 0 ----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+--- 220116/1300Z 115 05017KT 25.1F SNOW 9:1| 1.4|| 0.00|| 0.00|| 0.153 9:1| 7.3|| 0.12|| 0.00|| 0.80 100| 0| 0 220116/1400Z 116 04017KT 24.3F SNOW 8:1| 1.4|| 0.00|| 0.00|| 0.182 9:1| 8.8|| 0.12|| 0.00|| 0.98 100| 0| 0 220116/1500Z 117 05018KT 23.6F SNPL 7:1| 1.0|| 0.13|| 0.00|| 0.148 9:1| 9.7|| 0.25|| 0.00|| 1.13 55| 45| 0 220116/1600Z 118 05019KT 23.3F ZRPL 0:1| 0.0|| 0.13|| 0.05|| 0.115 9:1| 9.7|| 0.39|| 0.05|| 1.24 0| 58| 42 220116/1700Z 119 05020KT 22.9F ZRPL 0:1| 0.0|| 0.12|| 0.08|| 0.140 9:1| 9.7|| 0.51|| 0.13|| 1.39 0| 44| 56 220116/1800Z 120 05017KT 23.3F ZRPL 0:1| 0.0|| 0.07|| 0.01|| 0.044 9:1| 9.7|| 0.58|| 0.14|| 1.43 0| 77| 23 ----------------------------------------------+----++-----+-------------++--------------++-------------++-----------+---+--- 220116/2100Z 123 04013KT 24.0F FZRA 0:1| 0.0|| 0.00|| 0.04|| 0.033 9:1| 9.7|| 0.58|| 0.18|| 1.46 0| 0|100 220117/0000Z 126 31004KT 24.7F FZDZ 0:1| 0.0|| 0.00|| 0.04|| 0.042 9:1| 9.7|| 0.58|| 0.22|| 1.50 0| 0|100

18z gfs

Whatever falls isn't going anywhere quickly

@111 the energy is sitting on the Mississippi river border where 12z had it just inside Mississippi

18z GFS through 63 looks similar, maybe a touch east with the energy in the plains and a touch stronger with the high

You are most welcome! I'm trying not to leave anyone out

NAM/EURO/GFS

GSP .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 240 pm EST Tuesday: Looking ahead to the weekend, all attention turns toward the possibility of a winter storm that would affect the western Carolinas and northeast Georgia beginning perhaps as early as Saturday afternoon and possibly continuing through the better part of Sunday...emphasis on the word "possible". It is worth noting that the 12Z ECMWF has come around to the GFS idea that a strong short wave dropping southeastward along the High Plains would ultimately cut off an upper low over the central/srn Plains Friday night into Saturday. Also worth noting is the relative run-to-run consistency seen in the operational GFS with this feature. The setup begins Friday night into Saturday as the developing split in the flow helps to slow the progress of a large continental sfc high moving from Ontario, down across the lower lakes, to Upstate NY/New England Saturday/Saturday night. This would provide the necessary source for cold air prior to the arrival of the precip associated with the upper low, which operational guidance suggests will come across the lower MS Valley region Saturday night. The operational models show partial thickness values low enough to support at least a mix with wintry precip as we acquire isentropic lift on Saturday that could force the development of said precip by the afternoon. If this develops as it could, essentially as an activating warm front, it would help to lock in the cooler sfc temps before the main mid/upper forcing arrives from the west. The operational models all show a closed upper low rolling east on Sunday, moving overhead or to the south of the fcst area, then offshore/northeast on Sunday night. Be that as it may, this is not the only possible solution, and some of the ensemble members show very different outcomes to the upper/sfc pattern. Looking at the GEFS...there has been a definite trend toward more wintry precip across more of the fcst area, with the majority of ensemble members at 12Z showing wintry precip affecting nearly the entire fcst area Saturday night/Sunday. The plume diagrams, and their supposed total snow accumulations, appear most tantalizing. However, there are as many ensemble members showing minimal wintry precip as there are showing a great deal, and some still showing none at all. Our forecast will reflect developing confidence in the wintry scenario but limits the precip probs to the chance range for the time being. The trend is toward more of a snow possibility along/north of I-85 and more mixing/changing to sleet/freezing rain south of I-85, but this is only one scenario. The track of the low will determine how strong of a warm nose might develop from the south, which would greatly affect the precip-type distribution. The QPF blend right now is especially modest, and the conservative approach is preferable for a system that is still out on Day 4/5. In spite of the trend, readers are cautioned to manage their expectations...at least for the time being. Stay tuned. If this system develops as it could, we would be in for some NW flow snow on the TN border Sunday night into Monday, otherwise the remainder of the period would be quiet with a large sfc high settling across the region Monday into Tuesday.