December 16 2020 CTP Snowstorm Disco and Obs

[pawatch]

35 minutes ago, Itstrainingtime said:

What's the biggest storm on record at IPT?

Not sure I think 93...thinking 26" 

March 14, 2017 dumped about 20" for me.

[pasnownut]

Main attraction has arrived in northern Lanco.  Just beautiful.

Now I just count every hour of +SN as a win and see where we end up.

 

[MAG5035]

4 minutes ago, 2001kx said:

Think I have a shot at 12" back here?

Definitely, the radar seems set up real nice right now. You may miss the most intense bands but I think you should get to at least 12" without too much drama. 

[Jonesy56]

I can't remember the winds ramping up this early in previous major storms, ie grass still showing and its coming down sideways.

[Heisy]

Wish I could drive about 1 hour north/NW of Lewisburg. My car couldn’t handle it. Haha. Hopefully we have a shot at 18 in Lewisburg still, gonna be close thinking more like 14

[JTrout]

Got a lot of the crew in PA! 

[JTrout]

Sorry, not sure why the pic uploaded sideways 

[MAG5035]

37 minutes ago, Itstrainingtime said:

What's the biggest storm on record at IPT?

Per CTP discussion, it had to have been close but apparently March '93 must not have went down as a 24"+ in IPT. This storm has a chance to break all of that. 

.CLIMATE...
The last time there was 12+" of snow over a two day period (as
many storms will cross from one date into another):

State College:  6-7 Feb 2010 = 14.0"
Harrisburg:   20-21 Mar 2018 = 14.2"
Williamsport: 14-15 Mar 2017 = 18.4"

Last time there was an 24+" storm (not sayin`, just sayin`):

State College:  3-4 Mar 1994 = 27.7"
Harrisburg:   22-23 Jan 2016 = 30.2"
Williamsport: 12-13 Jan 1964 = 24.1" (the only two-foot storm
for Williamsport)

Highest two-day total:
State College: 29-30 Mar 1942 = 30.5"
Harrisburg:    22-23 Jan 2016 = 30.2" (that one, again)
Williamsport:  12-13 Jan 1964 = 24.1" (that one, again)

Higest two-day total in December:
Harrisburg: 24-25 Dec 1961 = 13.9"
Williamsport: 25-26 Dec 1969 = 17.2"

Highest one-day total in December:
Harrisburg: 23 Dec 1963 = 10.1"
Williamsport: 26 Dec 1969 = 14.7"
State College (7am-7am): 11 Dec 1992 = 12.5"

[paweather]

Winter Wonderland here now. 19z backed off a bit on mixing. 

[kdskidoo]

4 minutes ago, Wentzadelphia said:

Wish I could drive about 1 hour north/NW of Lewisburg. My car couldn’t handle it. Haha. Hopefully we have a shot at 18 in Lewisburg still, gonna be close thinking more like 14

I think 14" is easily doable.  all depends on the warm layer.  keeps moving north with most models.  my concern is a change to sleet at some point later tonight.

[paweather]

2 minutes ago, JTrout said:

Got a lot of the crew in PA! 

Cantore the kiss of snow death.

[canderson]

Really nice rates in HBG city. Really nice. 

[Voyager]

1 minute ago, paweather said:

Cantore the kiss of snow death.

But the creator of thundersnow...

[JTrout]

3 minutes ago, paweather said:

Cantore the kiss of snow death.

Gotta love the guys enthusiasm for weather! 

[JTrout]

1 minute ago, Voyager said:

But the creator of thundersnow...

Yea if you want 4” hour rates and some thunder snow.  He is your man

[Voyager]

I am NOT liking the 19z HRRR. That run shows sleet wrapping around all the way up to my location. It would be so nice to NOT taint for once.

[Festus]

Dry slot around mid Virginia moving north has me a little concerned.  What's the thinking of that either filling in or shutting us off?

[Gosnow]

From lititz in northern lanco.

 

[MAG5035]

Quote

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Major winter storm in progress throughout central PA with
snow reported at all central PA METAR stations since 18z with
+SN along and south of I-80. The storm is on track with previous
predictions and may challenge December snowfall records before
all is done on Thursday morning. Widespread snow accumulations
of 1-2 feet are expected along and east of I99, with snow rates
as high as 2-4 inches per hour this evening through late tonight.
Winter Storm Severity Index reaches the Extreme category for
many valley locations from the Central Mountains to the Pocono
Plateau, including State College proper.

Main changes since previous update were to decrease snow totals
due to mixing with sleet over far Lower Susq (southern York and
Lancaster Counties), increase amounts slightly from Central
Mountains to the Endless Mountains, where confidence has
increased in 20"+ amounts, with consensus there for localized 2
foot+ before the storm winds down early Thursday morning.

Today`s focus was on evaluating the timing and location of
heaviest snowbands, where where some 2-4" per hour rates are
possible from late this afternoon through late this evening
central and east. Guidance has shifted ever so slightly farther
west with the higher intensity frontogenetical/CSI banding,
increasing the likelihood for widespread foot plus amounts and
much of the area in the 18-24" range for this storm. HRRR has
spot amounts exceeding 30", but confidence in that outlier solution
is on the lower side. However, if a situation could produce
those amounts and we could achieve 15:1 snow ratios from the
anticipated QPF, this cannot be ruled out. Given the height of
the DGZ, slightly less than ideal fluff factor is present and
suggests snow ratios in the 12:1 inch range. Peak period of
CSI-banded heavy snow comes mid to late evening with the
potential for thunder snow as the nose of a strong, 50-60 kt
easterly 850 mb jet and 130 kt upper jet focuses hefty uvvel and
slantwise instability near and just to the NW of the I-81
corridor.

Cold Conveyor belt/FGEN moderate snows with near 1 inch per hour
snowfall rates should linger until around, or shortly after
daybreak from KUNV to KIPT and points NE, leading to the axis of
heaviest snow near or just to the SE of that axis with some
areas seeing 18-20 inches for high-end storm total amounts.

The storm will be relatively quick moving, with most places
seeing precip for 18-24 hours. Nonetheless, with cold
temperatures in place, good SLRs, and very strong frontogenesis,
this should end up being the most significant snowstorm for
most of the area since November 2018... and for some areas,
perhaps one of the heaviest snow events in the past 5+ years. It
also may rival some of the record 1-day and 2-day December snow
totals. For reference, the December 2-day record snowfall at
Harrisburg is 13.9 inches, set in 1961.

[Caveman]

+SN for last hour, Etters, PA and very wintry.  These old bones say "It's cold"!

 

[pasnownut]

3 minutes ago, MAG5035 said:

I swear. WTF is it with the outline around Lanco. FFS

[JTrout]

2 minutes ago, pasnownut said:

I swear. WTF is it with the outline around Lanco. FFS

Ever hear of the warm nose! Lancaster is kinda nose like in shape, so they thinks it’s funny!! Haha

[dj88]

LOL why is any line for any map always drawn through Elysburg... I swear we are always on a "line"

 

[2001kx]

28 minutes ago, MAG5035 said:

Definitely, the radar seems set up real nice right now. You may miss the most intense bands but I think you should get to at least 12" without too much drama. 

Thanks mag.. 

[pasnownut]

Crankin in Lanco.

for now. Parachutes...big ones. 

[NeffsvilleWx]

2 minutes ago, pasnownut said:

Crankin in Lanco.

for now. Parachutes...big ones. 

 

Not here. Average sized flakes.

[kerplunk]

4” here - 23/20 - another good slug moving in from the SW.

[Itstrainingtime]

5 minutes ago, pasnownut said:

Crankin in Lanco.

for now. Parachutes...big ones. 

 

2 minutes ago, NeffsvilleWx said:

 

Not here. Average sized flakes.

It's been pouring snow here for some time now, and flake size is fluctuating between large and small flakes constantly. 

[Superstorm]

Pouring snow!!

Hoping in lasts a few hours.


.

[Itstrainingtime]

4:00pm measurement: 2.8"