Central PA Winter 2024/2025

[Bubbler86]

2 minutes ago, mitchnick said:

I love ya' Bliz, but those 10:1 accumulation maps will never verify with these marginal events. Kuchera are far from perfect, but will end up being much more accurate with their reduced totals.

And nothing is laying on major roads.  I am not calling for anything of consequence south of Harrisburg right now.   I believe 2M temps will be in the 35-40 range in our areas. 

[Blizzard of 93]

4 minutes ago, mitchnick said:

I love ya' Bliz, but those 10:1 accumulation maps will never verify with these marginal events. Kuchera are far from perfect, but will end up being much more accurate with their reduced totals.

We have an Arctic air mass in place with cold ground temps.

 

[mitchnick]

Just now, Bubbler86 said:

And nothing is laying on major roads.  I am not calling for anything of consequence south of Harrisburg right now.   I believe 2M temps will be in the 35-40 range in our areas. 

You'll have a much better shot at accumulations with your elevation. I'll need to drive 6 minutes up to the peak of Pigeon Hills. Either way, everyone melts and/or gets washed away.

Honestly, this move up here hoping for more snow has been disappointing to say the least. Snow nirvana it ain't! Lol

[Blizzard of 93]

4 minutes ago, Blizzard of 93 said:

We have an Arctic air mass in place with cold ground temps.

 

Also, precip coming mostly at night, so the dreaded mid December sun angle won’t impact much.

[Bubbler86]

6 minutes ago, mitchnick said:

You'll have a much better shot at accumulations with your elevation. I'll need to drive 6 minutes up to the peak of Pigeon Hills. Either way, everyone melts and/or gets washed away.

Honestly, this move up here hoping for more snow has been disappointing to say the least. Snow nirvana it ain't! Lol

Yea, I always chuckle when I see the MA folks talk about Hanover, York, etc as snow towns.    But yea I may see something if it gets here early enough.  Like mentioned above, if it arrives after dark it is a full rain IMO.    The 540 line (and even worse in other layers of the column) is retreating in response to the WAA. 

[Blizzard of 93]

SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
Focus tonight into Sunday morning is on approaching 5h trough
swinging into the high plains Saturday and middle to upper
Mississippi River Valley tonight and to the lower central GLAKS
on Sunday. Strong easterly ageostrophic flow around anomalous
arctic high pressure over the Gulf of Maine and and weak sfc
trough with approaching system on Sunday means that cold air
from the retreating arctic high will be very difficult to
dislodge. CAD entrenched along and to the east of the Allegheny
Mtns will set the stage for overrunning mixed precip Sunday into
Sunday night. Model trends indicate S/IP as most likely Ptype
well east of the Alleghenies with a good signal for fzra/icing
closer to the Alleghenies. Confidence was sufficient for near
warning criteria fzra over the Laurel Highlands to hoist a
Winter Storm Watch for .25"+ potential ice amounts, with
Advisories stretching northward through Clearfield, Elk and
Cameron Counties (coordinated with PBZ).

The depth of the cold air will be a major factor in determining
the amount of frozen (snow and sleet) versus liquid (freezing
rain and rain) precipitation. The bulk of the wintry mix and
snow/ice accumulation should stay along and to the northwest of
I81. As far as snow accumulations go, Advisory criteria
snow/sleet is looking increasingly likely over parts of the
Central Mountains, Ridge and Valley Region, and up towards the
Endless Mountains region of northeast PA. It appears that hourly
snowfall rates of .25" to .5" at times Sunday afternoon and
evening bring the best chances for 2-4 inches of snow to an area
stretching from State College to Lewisburg, Bloomsburg to Lock
Haven and back to Philipsburg, with 1 to 2.5" amounts common
across the remainder of central and north central PA (south of
Rt 6). Amounts drop off south of I-81, and along the Alleghenies
where ptypes are more likely to be freezing rain and sleet.

 

[mitchnick]

2 minutes ago, Blizzard of 93 said:

We have an Arctic air mass in place with cold ground temps.

 

True. But it's a retreating arctic High with SE winds and there's not the kind of model consensus you'd expect for a decent accumulation event. Don't get me wrong. Higher elevations will likely do as advertised, but imho anything to the south and east of the mts under 2" on the 10:1 maps will likely be 1/2" or less.

[Blizzard of 93]

Just now, Blizzard of 93 said:

SHORT TERM /6 PM THIS EVENING THROUGH MONDAY/...
Focus tonight into Sunday morning is on approaching 5h trough
swinging into the high plains Saturday and middle to upper
Mississippi River Valley tonight and to the lower central GLAKS
on Sunday. Strong easterly ageostrophic flow around anomalous
arctic high pressure over the Gulf of Maine and and weak sfc
trough with approaching system on Sunday means that cold air
from the retreating arctic high will be very difficult to
dislodge. CAD entrenched along and to the east of the Allegheny
Mtns will set the stage for overrunning mixed precip Sunday into
Sunday night. Model trends indicate S/IP as most likely Ptype
well east of the Alleghenies with a good signal for fzra/icing
closer to the Alleghenies. Confidence was sufficient for near
warning criteria fzra over the Laurel Highlands to hoist a
Winter Storm Watch for .25"+ potential ice amounts, with
Advisories stretching northward through Clearfield, Elk and
Cameron Counties (coordinated with PBZ).

The depth of the cold air will be a major factor in determining
the amount of frozen (snow and sleet) versus liquid (freezing
rain and rain) precipitation. The bulk of the wintry mix and
snow/ice accumulation should stay along and to the northwest of
I81. As far as snow accumulations go, Advisory criteria
snow/sleet is looking increasingly likely over parts of the
Central Mountains, Ridge and Valley Region, and up towards the
Endless Mountains region of northeast PA. It appears that hourly
snowfall rates of .25" to .5" at times Sunday afternoon and
evening bring the best chances for 2-4 inches of snow to an area
stretching from State College to Lewisburg, Bloomsburg to Lock
Haven and back to Philipsburg, with 1 to 2.5" amounts common
across the remainder of central and north central PA (south of
Rt 6). Amounts drop off south of I-81, and along the Alleghenies
where ptypes are more likely to be freezing rain and sleet.

 

Here is CTP’s take on tomorrow night.

Looks like our first widespread Advisory event for many of us is on the way tomorrow.

[Bubbler86]

Also, check out the high on the Rgem (first) and the high on GFS (second).  Major difference in protecting against a WAA battle

[mitchnick]

6 minutes ago, Blizzard of 93 said:

Also, precip coming mostly at night, so the dreaded mid December sun angle won’t impact much.

My forecast has rain and snow starting at 1PM. I'm sure I'll have snow TV, but it's the accumulations I doubt.

[Blizzard of 93]

2 minutes ago, mitchnick said:

True. But it's a retreating arctic High with SE winds and there's not the kind of model consensus you'd expect for a decent accumulation event. Don't get me wrong. Higher elevations will likely do as advertised, but imho anything to the south and east of the mts under 2" on the 10:1 maps will likely be 1/2" or less.

Arctic air is tough to dislodge… CTP said it in their discussion.

If the precip comes in as a solid “wall”, this should produce from around I -81 on to the north & west.

[mitchnick]

6 minutes ago, Bubbler86 said:

Yea, I always chuckle when I see the MA folks talk about Hanover, York, etc as snow towns.    But yea I may see something if it gets here early enough.  Like mentioned above, if it arrives after dark it is a full rain IMO.    The 540 line (and even worse in other layers of the column) is retreating in response to the WAA. 

There was a big difference in a number of years from the 90's to before I moved up here. And I did do substantially better than BWI in 20/21 and better last year. But not so in the other 3 years.

[mitchnick]

2 minutes ago, Blizzard of 93 said:

Arctic air is tough to dislodge… CTP said it in their discussion.

If the precip comes in as a solid “wall”, this should produce from around I -81 on to the north & west.

There's no doubt, my southern location is a problem. But getting back to my original post, I just don't think the 10:1 accumulation maps are going to be as accurate as the Kuchera. That's really all I'm saying.

[Bubbler86]

3 minutes ago, mitchnick said:

There was a big difference in a number of years from the 90's to before I moved up here. And I did do substantially better than BWI in 20/21 and better last year. But not so in the other 3 years.

There is definitely a difference but Adams, York and Lanco change over real fast with marginal temps. 

[canderson]

What’s the timing for tomorrow’s event? 

[AccuChris]

Long range 12z HRRR is slightly more generous in snowfall for tomorrow and tomorrow night


.

[Bubbler86]

Just now, AccuChris said:

Long range 12z HRRR is slightly more generous in snowfall for tomorrow and tomorrow night


.

It starts the precip earlier which is one for Team Snow.  Hard to compare from 6Z though as that run did not cover the entire event. 

[Blizzard of 93]

Here is the 6z Euro ensemble 

[Mount Joy Snowman]

Low of 18. 

[Bubbler86]

NAM brought precip in faster

 

[mitchnick]

9 minutes ago, Bubbler86 said:

NAM brought precip in faster

 

Don't look at the 3k.

[Bubbler86]

Just now, mitchnick said:

Don't look at the 3k.

It actually improved slightly as to snow presentation.  Neither are anything but white rain/mulch snow for much of the LSV IMO.  Just a better white rain that 6Z. 

[Wxdavis5784]

58 minutes ago, mitchnick said:

You'll have a much better shot at accumulations with your elevation. I'll need to drive 6 minutes up to the peak of Pigeon Hills. Either way, everyone melts and/or gets washed away.

Honestly, this move up here hoping for more snow has been disappointing to say the least. Snow nirvana it ain't! Lol

Agreed.

I'm on my 4th winter here and I think we have had 1 warning level event in 21-22. 

[ChescoWx]

This morning's low of 17.5 degrees was our coldest morning here in East Nantmeal since last February 18th when the low was 15.2 degrees. Today will mark our 10th below normal day over the 1st 14 days of December. We start a brief moderating trend tomorrow with temperatures getting above normal by Monday PM. Our mildest day will be Tuesday when we rise into the low to mid 50's. Another cool down will start by Tuesday evening. Rain and even a little freezing drizzle could arrive toward midnight tomorrow night. Rain should continue a good bit of the time through Tuesday. By the end of the work week, we could see another chance of some rain or wet snow.

[CarlislePaWx]

Guys, I'm surprised no one has mentioned the current barometric pressure.  Here at the moment it is 30.91" or 1047 millibars!  This is the highest pressure I've seen in years.  At the very least I know we never got this high during all of last winter.  One very interesting thing is that frequently in these types of setups where very high pressure (usually closer to 30.70") is present, and precip is forecast to arrive approximately 24 hours later, freezing rain is oftentimes the predominant p-type.  For me, this area is usually the last to give up the cold when there is cold air damming.  I cannot speak as to how much snow I might see since I am literally 1 mile south of I-81, but when it does go over to rain, there may be a prolonged period of freezing rain.  (Everything I have just talked about is referencing my location of central Cumberland county.)

[Blizzard of 93]

12z RGEM still looks good for around I-81 back to the north & west.

[Superstorm]

12z RGEM still looks good for around I-81 back to the north & west.

What is timing on this?


.

[Blizzard of 93]

9 minutes ago, Superstorm said:

What is timing on this?


.

CTP for now for the Harrisburg area is saying mainly after 4 pm.

[Ruin]

Any idea why we have this cloud cover today

[WmsptWx]

17 minutes ago, Ruin said:

Any idea why we have this cloud cover today

Fires in Canada lol