Blizzard of 93

Here are the latest EPS & GEFS ensembles which continue to target CTP with heavy snow.

Here is the 0z Euro for today’s appetizer.

Here is the 0z Euro snow map for just this event, not including anything today!

The 0z Euro did bring the Euro up over Delaware before heading east to the south NJ coast. Our true central to 1-81 & Rt 15 crew would get crushed with this track, while Lancaster would have the chance of temporary mixing with the Euro track. Once the final track is nailed down over the next day or 2, then we can see where the deform band sets up and look at thermals got any mixing issues or snow to liquid ratios.

Yes, we just need to move the 0z Euro low track about 25 miles further east to limit the chance of any mixing for @pasnownut

I would sign up for this 6z GFS as well.

CTP agrees that elevation should help tomorrow, but most places in southern PA should get 1 to 2 inches of snow. “Model soundings indicate precipitation will start as rain over the Lower Susq Valley. However, wet-bulbing of the low levels and increased deep-layer uvvel will likely lead to a quick changeover to wet snow, that could be briefly moderate in intensity from I-81 southward during the 14Z-18Z time frame. A blend of latest model guidance supports a light accumulation of wet snow across primarily the southern tier of the forecast area. With temperatures above freezing in many spots, expect accumulations to be highly elevation dependent. In general, expect 1-2 inches across the southern tier of the state and just a coating further north. However, the higher elevations of southern Pa, such as South Mountain, could see close to 3 inches. Since temps will be in the 31-35F range for the duration of the snow, most treated roads in the valleys should stay wet. Most susceptible roads to a light slushy covering will be those traversing the tops and north sides of ridges where insolation through the thick cloud cover will be minimal. The back edge of the snow should be exiting the central mountains by 15Z and the southeast corner of the forecast area by around 19Z, as surface low pushes east of the Delmarva.”

Here is the 0z Canadian super zoomed in for CTP. The 10 to 1 map is impressive, but the Kuchera map should be illegal!

Here is a closer look at the GFS. It has a more offshore track than the other models, but that would limit mixing for our southeast crew. About 3 inches of this falls tomorrow morning in the Harrisburg area. Here are the 10 to 1 and Kuchera ratio maps.

Most models seem to be on board for at least 1 to 3 inches of snow tomorrow in southern PA. The 0z GFS is on board with 1 to 3 inches of snow tomorrow.

Harrisburg is already down to 35 degrees and the radar looks juiced in Kentucky & Tennessee. The NAM might be on the right track.

That makes sense. They are doing a good job getting the word out about the major storm. It’s good that they are not down playing tomorrow if we get a couple inches of snow in the morning.

My. Holly just hoisted Winter Storm Watches for most of their region! CTP probably will be considering to post a Watch as well. However, southern PA has the Advisory posted for tomorrow morning. We have the possibility of the elusive super rare Advisory and Watch at the same time!

For tomorrow, the 0z NAMs and HRRR are looking good for southern PA snow.

The 1037 High just says anchored in to the north while low crawls along the DelMarVa!

Here is the height of the storm on the 18z Euro.

The 18z Euro is finally on board again for the appetizer event tomorrow.

I think we are all in great shape from I-99 on east!

Epic crushing!

The 18z Euro is on board now for tomorrow’s event..., And an epic mauling in ongoing this run for Wednesday night!

Crushed! We are starting to get a consensus. Only 3 days out now.

If the NAM is correct, it usually needs to be 1 day out or less. It’s supported by the HRRR too. If we get decent rates, then a few inches are possible.

The 18z NAMs are upping the ante for southern PA and northern MD. @psuhoffman , Please let us know your thoughts on the appetizer event for tomorrow.

Meanwhile, hot off of the press from CTP for tomorrow morning for the LSV. Winter Weather Advisory URGENT - WINTER WEATHER MESSAGE National Weather Service State College PA 137 PM EST Sun Dec 13 2020 PAZ036-057-059-063>066-141000- /O.NEW.KCTP.WW.Y.0017.201214T1100Z-201214T2100Z/ Franklin-Dauphin-Lebanon-Cumberland-Adams-York-Lancaster- Including the cities of Chambersburg, Harrisburg, Hershey, Lebanon, Carlisle, Gettysburg, York, and Lancaster 137 PM EST Sun Dec 13 2020 ...WINTER WEATHER ADVISORY IN EFFECT FROM 6 AM TO 4 PM EST MONDAY... * WHAT...Wet snow expected. Total snow accumulations of 1 to 2 inches throughout the Susquehanna Valley, with around 3 inches likely on the ridges. * WHERE...Portions of central Pennsylvania. * WHEN...From 6 AM to 4 PM EST Monday. * IMPACTS...Plan on slippery road conditions. The hazardous conditions could impact the morning commute. * Additional Details...Snowfall rates of up to 1 inch per hour are possible at times near and to the south of the Pennsylvania Turnpike during the late morning and early afternoon hours.