Blizzard of 93

Winter Weather Advisory URGENT - WINTER WEATHER MESSAGE National Weather Service State College PA 411 AM EST Thu Feb 24 2022 PAZ010>012-018-019-026>028-035-036-045-056-063>065-242115- /O.NEW.KCTP.WW.Y.0014.220225T0000Z-220225T1500Z/ Elk-Cameron-Northern Clinton-Northern Centre-Southern Centre- Huntingdon-Mifflin-Juniata-Fulton-Franklin-Southern Clinton-Perry- Cumberland-Adams-York- Including the cities of St. Marys, Ridgway, Emporium, Renovo, Philipsburg, State College, Huntingdon, Mount Union, Lewistown, Mifflintown, McConnellsburg, Chambersburg, Lock Haven, Newport, Carlisle, Gettysburg, and York 411 AM EST Thu Feb 24 2022 ...WINTER WEATHER ADVISORY IN EFFECT FROM 7 PM THIS EVENING TO 10 AM EST FRIDAY... * WHAT...Mixed precipitation expected. Total sleet and snow accumulations of up to 3 inches and ice accumulations between one tenth and one quarter of an inch. * WHERE...Portions of central Pennsylvania. * WHEN...From 7 PM this evening to 10 AM EST Friday. * IMPACTS...Plan on slippery road conditions. The hazardous conditions will impact the morning commute. Travel disruptions are expected to be significant overnight for all of the area, and into mid-morning Friday north of Route 22. * ADDITIONAL DETAILS...Any snow at the beginning of the precipitation this evening will quickly turn to sleet. Several hours of sleet will be followed by several hours of freezing rain. This combination will create a thick layer of ice. Temperatures will gradually warm to just above freezing in most places late tonight or on Friday morning. Gusty west winds on Friday may lead to power outages as the icy trees could fall onto power lines. The heavier than normal power lines themselves will also be subjected to increased stress from the wind.

The 0z 3k NAM ramped up sleet amounts for the LSV, along with the rest of CTP. 0z top vs 18z bottom

Selinsgrove went from 1.7 to 4.0 Reading went from .6 to 2.2 Still some time left for another tick or 2 south.

The cold air is really pressing into northwest PA as of 8 pm. Temps in the low 20s with dew points in the mid teens. Once the cold continues its press and gets established in the rest of PA by tomorrow, it’s going to be tough to dislodge.

The 18z Euro did push the snow line further south. The 2 inch snow line now gets into Dauphin & Lebanon county. 18z top vs. 12z bottom

Good points… I think they spend way too much time worrying about their precious “criteria” instead of getting the proper message out to protect the life & property of the people; which is stated as their primary mission.

It’s not the only bad thing in Dallas….. (sorry, you set that one up! Lol!)

Lol times a million……. But I didn’t think ice could accumulate on ground that was recently warm and only at temps of 31 degrees….. There might be a chance this happens on PA roads tomorrow night & Friday am…. Lol!

Winter weather is far far far far far far from over! March will be our snow month!

@MAG5035 Mt. Holly & Binghamton have Watches, but I guess if you cross the border from Berks to Lebanon or from Luzerne to Schuylkill county, no Watch type weather to worry about!

CTP up to their usual stuff…

The local ABC-27 Met. Brett this morning said he wasn’t expecting much trouble on the untreated roads. CTP disagreed with that in their discussion that I just posted. If places get a few hours of sleet before the freezing rain, this will provide a colder surface for freezing rain accretion. Most models get temps from the high 20’s to low 30’s even in the LSV, so sleet + freezing rain could create a “brick” on surfaces as CTP mentioned.

Great discussion from CTP this morning. ”The storm of note will be gathering over the TN valley on Thursday. Some light precip (snow??) is expected to arrive later in the day. NAM very aggressive with generating meas precip/light snow over much of the CWA during the daylight hrs. However, other model solutions hold it off for almost all day long. Much uncertainty remains with how this storm will affect the CWA. At this point, the low center will prob pass over our NW counties early Fri AM. Warm air flows in overhead Thursday night, and will likely make a prolonged period of mixed precip. Cold air will get reinforced by a cold air damming setup Thursday night. Broad srly 8H winds >40KT will supply plenty of GOMEX mstr. Most places north of the Turnpike get down below freezing Thurs evening and stay there until mid-morning Fri. The setup/signal for FZRA is strong(est) over the Laurel Highlands. WPC guidance, BUFKIT soundings and SREF probs make a good case for 0.25"+ of FZRA between 00Z and 12Z at JST. QPF thru that time is >1" with some of that falling as PL and it could turn to rain near the end of the night in Somerset Co. The sleet-heavy soundings from NAM put down 1" of sleet accums (at like a 4:1 SLR). That amount of sleet can wreak havoc on the roads, esp if people drive on it and compact it. However, the sleet would cut down on snow totals. The nrn tier is least susceptible to a turn-ovber to sleet. However, no guidance points to all snow in the north - it turns to a mix there, too. Precip type change-over timing is very much in doubt. So many what- ifs give low confidence to snow/sleet amounts, and the ice accums, too. Have decided to post a winter storm watch for the Laurels as this appears to be the most-certain area to garner signif ice accretions. Everyone south of I-80 may get 0.10-0.25" of ice, too, and may eventually go to an advy, but confidence in warning levels of snow/sleet/FZRA not there, yet. Thus, no watches elsewhere at this point. I could see posting watches/warnings later for sub- criteria amounts of straight snow if we end up getting a sig amount (1"+) of pure sleet, or sleet topped by a sig glaze of ice. It`ll just harden into a brick, and is not easy to clear from the roads/sidewalks. We had that once already this winter locally. Friday looks like it will be a "snow day" for most schools in Central PA.”

The 3k NAM came in colder and really delivers the heavy sleet even to the LSV.

Good discussion from CTP on this event: Main focus this period remains on southern stream shortwave and associated surface low lifting northeast toward Pa late Thursday into early Friday. The bulk of latest guidance tracks the primary low into western Pa with a weak secondary coastal low development and a blocking high over northern New England. This scenario favors a wintry mix for much of central Pa late Thursday into through Friday morning. Plenty of GOMEX moisture/above normal PWs accompanying this system should result in a fairly significant precipitation event, with latest ensemble plumes indicating 0.5 to 1.25 inches of [liquid equivalent] precip most likely. Latest model thermal profiles currently support snow to mixed precip over the north and mixed precip to rain in the south. We were keen to utilize NBM unconditional PoWT to derive wx types and used a blend of NBM/WPC/NBM v4.1/EXP for snow and ice accumulations. The heaviest/significant snow accums 4+ inches are most likely north of I-80 across the northern tier of CPA. A broad wintry mix zone of snow, sleet, and freezing rain is probable mainly from US-6 south to the PA Turnpike, with a icy mix to rain transition fcst from the PA Turnpike south to the MD line. The exception will be across the Laurel Highlands, with a high probability of >0.25" of ice accumulation based on the aforementioned multi model blend and supported by the WPC WWO. We will wait another cycle before considering headlines; but this event looks like a solid advisory for most of CPA pushing warning criteria for ice in the Laurels and for snow across the northern tier. Hazardous travel conditions are very likely later Thursday into Friday (HWO).

The 18z Euro & RGEM have CTP in the freezing rain bullseye Thursday night into Friday. The message, regardless of the amounts, is that there is a good chance of significant freezing rain with this event in our region. Hopefully we get the ground a little snow & sleet covered before the freezing rain takes over.

18z GFS is trying to bring back the Sunday snow chance.

This is one interesting CTP forecast for southern Perry county! Thursday Night Rain, snow, freezing rain, and sleet. Low around 31. Southeast wind 5 to 8 mph. Chance of precipitation is 100%. New snow and sleet accumulation of 1 to 2 inches possible. Friday Rain, freezing rain, and sleet before 7am, then rain or freezing rain between 7am and 1pm. High near 40. Chance of precipitation is 90%. New sleet accumulation of less than a half inch possible.

It will be interesting the next 2 days to see how the short range models forecast the final lines for the snow, sleet & freezing rain and temperatures for Thursday/Friday.

We should have our chances through the first half of March with the -EPO delivering the cold.

Still a couple of days to go to get this to trend back to a couple of front end inches of snow in parts of the LSV before the icy mix wins out.

The 0z GFS brings more sleet than prior recent runs between the turnpike & I-80 followed by a prolonged period of freezing rain. Temps don’t rise to above freezing until around 10am Friday according to this run.

The 0z RGEM ends with Harrisburg at 28 degrees at 7am on Friday with sleet changing over to freezing rain. Heavy amounts of sleet get put down this run between the turnpike & I-80.

The 18z Euro is still icy for all of CTP. Here is the ice and surface temps at 12z Friday which is the end of the run.

I agree, I like where the Sunday system is sitting at this time. With the Thursday/Friday storm, we were once on the southern edge of the snow bullseye, and now it looks like congrats to I-90 to Massachusetts. For the Sunday chance, we are on the northern & western fringe currently with 6 days to go. Let’s reel this Sunday chance in!