January 24-26: Miracle or Mirage Thread 2

[snowfan]

[JenkinsJinkies]

6 hours ago, Ralph Wiggum said:

I thought you were out?

If you read the 2nd part of that I said I’d be back in if 6z stopped the bleeding. So far so good.

[Ji]

Could be a top 10 in Dulles ??

[Jebman]

This is a very very alarming excerpt from the latest Richmond AFD as of 248am EST.

https://forecast.weather.gov/product.php?site=AKQ&issuedby=AKQ&product=AFD&format=CI&version=1&glossary=1&highlight=off

 

A variety of precipitation types are expected in this setup
with big differences as you head NW to SE across the forecast
area. Cold air holds strong at the surface for inland areas as
the wedge reinforces. Warmer air likely intrudes across the far
SE, with temperatures potentially climbing into the upper 40s to
around 50 while areas across the NW stay in the lower 20s. In
addition, all guidance indicates some form of a warm nose
developing around ~850mb, potentially spreading as far inland as
the NW Piedmont. This will result in a messy situation with
snow, sleet, freezing rain, and plain rain possible across the
forecast area. The thickness and strength of the eventual warm
nose is what will ultimately decide our precipitation types.
Precipitation likely starts off as all snow for a majority of
the area Saturday afternoon-evening, spreading north from the
south. A change over then occurs from SE to NW with areas across
the far SE changing to plain rain. Meanwhile, it gets messier
further inland with snow/sleet/freezing rain all being possible
Saturday night into Sunday night. Right now far NW portions of
the area would be favored for the most snowfall, while areas
south of I-64 and along/west of I-95 would be favored for more
icing (see further details about both below). Whatever form of
wintry precipitation that does fall will be significant, hence
the Winter Storm Watches.

Ice: After looking at the 00z guidance, am really starting to
get concerned that a good portion of the area may see
significant to potentially catastrophic ice impacts. The latest
NBM indicates a 30- 50% chance for AT LEAST 0.50" of freezing
rain for much of the area along/south of I-64 from our western
border over to the western Tidewater and up to the Middle
Peninsula. 1.00" probabilities of freezing rain have increased
to near 20% across South Central Virginia which may be too low.
Even more concerning, the EPS Mean accumulation of freezing rain
ranges from 1.00-1.50" across the same locations, with the
deterministic ECWMF showing even higher/more alarming numbers.
It is possible that the EPS/ECMWF, are overdoing the freezing
rain and some of this QPF may be sleet instead (from glancing at
model soundings), but even half of these amounts will result
and a significant ice storm. Ice accumulation of this magnitude
would likely result in major travel impacts as well as
widespread and long-lasting power outages.

Snow: Snow probabilities remain fairly steady, favoring the far
northern half of the area up to DC. The probabilities for
greater than 12" of snow (off of the NBM) range from 40-60% for
much of the northern half of the forecast area, with even higher
probabilities (60-80%+) for at least 6". I am concerned these
values may be overdone, especially the further south you go, due
to substantial mixing of sleet and/or freezing rain. There will
likely be a very sharp cutoff in snow amounts (from north to
south) just over or near the northern half of the forecast area
which we will still need to fine tune with future forecasts.

Everyone should take note and begin to make preparations for a
significant snow/icing event as moderate to major (potentially
extreme) impacts are looking increasingly likely from this
storm. In addition, after effects from the storm will likely
last well into the work week due to very cold temperatures.

I am sorry if this has been mentioned before but this situation is SERIOUS BUSINESS.

I am very concerned about those higher numbers. A few years ago I personally experienced three quarters of an inch of ice in Buda, TX. The effect on the oaks down here were alarming to say the least. Ice in excess of 1.50 inches is something I can not even begin to imagine. South Virginia and parts of North Carolina will very likely become disaster zones deteriorating into outright humanitarian catastrophes.

[Interstate]

What did the 6z CMC say?

[Ralph Wiggum]

What time does the morning euro come out?

[TSSN+]

Just now, Ralph Wiggum said:

What time does the morning euro come out?

620

[Snowlover11]

Just now, Ralph Wiggum said:

What time does the morning euro come out?

6:30 ish

[Solution Man]

2 minutes ago, Jebman said:

This is a very very alarming excerpt from the latest Richmond AFD as of 248am EST.

https://forecast.weather.gov/product.php?site=AKQ&issuedby=AKQ&product=AFD&format=CI&version=1&glossary=1&highlight=off

 

A variety of precipitation types are expected in this setup
with big differences as you head NW to SE across the forecast
area. Cold air holds strong at the surface for inland areas as
the wedge reinforces. Warmer air likely intrudes across the far
SE, with temperatures potentially climbing into the upper 40s to
around 50 while areas across the NW stay in the lower 20s. In
addition, all guidance indicates some form of a warm nose
developing around ~850mb, potentially spreading as far inland as
the NW Piedmont. This will result in a messy situation with
snow, sleet, freezing rain, and plain rain possible across the
forecast area. The thickness and strength of the eventual warm
nose is what will ultimately decide our precipitation types.
Precipitation likely starts off as all snow for a majority of
the area Saturday afternoon-evening, spreading north from the
south. A change over then occurs from SE to NW with areas across
the far SE changing to plain rain. Meanwhile, it gets messier
further inland with snow/sleet/freezing rain all being possible
Saturday night into Sunday night. Right now far NW portions of
the area would be favored for the most snowfall, while areas
south of I-64 and along/west of I-95 would be favored for more
icing (see further details about both below). Whatever form of
wintry precipitation that does fall will be significant, hence
the Winter Storm Watches.

Ice: After looking at the 00z guidance, am really starting to
get concerned that a good portion of the area may see
significant to potentially catastrophic ice impacts. The latest
NBM indicates a 30- 50% chance for AT LEAST 0.50" of freezing
rain for much of the area along/south of I-64 from our western
border over to the western Tidewater and up to the Middle
Peninsula. 1.00" probabilities of freezing rain have increased
to near 20% across South Central Virginia which may be too low.
Even more concerning, the EPS Mean accumulation of freezing rain
ranges from 1.00-1.50" across the same locations, with the
deterministic ECWMF showing even higher/more alarming numbers.
It is possible that the EPS/ECMWF, are overdoing the freezing
rain and some of this QPF may be sleet instead (from glancing at
model soundings), but even half of these amounts will result
and a significant ice storm. Ice accumulation of this magnitude
would likely result in major travel impacts as well as
widespread and long-lasting power outages.

Snow: Snow probabilities remain fairly steady, favoring the far
northern half of the area up to DC. The probabilities for
greater than 12" of snow (off of the NBM) range from 40-60% for
much of the northern half of the forecast area, with even higher
probabilities (60-80%+) for at least 6". I am concerned these
values may be overdone, especially the further south you go, due
to substantial mixing of sleet and/or freezing rain. There will
likely be a very sharp cutoff in snow amounts (from north to
south) just over or near the northern half of the forecast area
which we will still need to fine tune with future forecasts.

Everyone should take note and begin to make preparations for a
significant snow/icing event as moderate to major (potentially
extreme) impacts are looking increasingly likely from this
storm. In addition, after effects from the storm will likely
last well into the work week due to very cold temperatures.

I am sorry if this has been mentioned before but this situation is SERIOUS BUSINESS.

I am very concerned about those higher numbers. A few years ago I personally experienced three quarters of an inch of ice in Buda, TX. The effect on the oaks down here were alarming to say the least. Ice in excess of 1.50 inches is something I can not even begin to imagine. South Virginia and parts of North Carolina will very likely become disaster zones deteriorating into outright humanitarian catastrophes.

Don’t want to see that. I pray that does not happen 

[TSSN+]

I passed out at 945 last night lol. Staying up the two prior nights killed me. But glad I woke up to still in the game. 6z euro out shortly. 

[Solution Man]

1 minute ago, TSSN+ said:

I passed out at 945 last night lol. Staying up the two prior nights killed me. But glad I woke up to still in the game. 6z euro out shortly. 

You’ll be primed today, wandering what happened to you

[poolz1]

Couldn't stay awake for the runs last night either.  Needed a good night's sleep.

Hopefully, we have seen the constant jumps north come to and end after the 6z gfs.  The first run I have seen that actually had a slight bump south.  Unless I am missing anything.  Too many posts to sift through! Hoping the euro at least holds. 

[Solution Man]

1 minute ago, poolz1 said:

Couldn't stay awake for the runs last night either.  Needed a good night's sleep.

Hopefully, we have seen the constant jumps north come to and end after the 6z gfs.  The first run I have seen that actually had a slight bump south.  Unless I am missing anything.  Too many posts to sift through! Hoping the euro at least holds. 

Your rested eyes saw it correctly 

[mitchnick]

9 minutes ago, Interstate said:

What did the 6z CMC say?

GREAT!!!

Link to all the parameters.

https://meteocentre.com/numerical-weather-prediction/forecast-systems.php?lang=en&mod=cmc_gdps

[Jebman]

4 minutes ago, Solution Man said:

Don’t want to see that. I pray that does not happen 

On that we both agree fervently. Its not just the ice and the outages and damages to trees/shrubs vegetation, vehicles, structural damages to buildings and electrical/communications infrastructure and massive pileups on highways to say nothing of people trying to walk to warm places on solid highly slippery glacierlike ice substrates, but the extremely cold air, devastating wind chills which will make this a very difficult dilemma for responders attempting to help people in need.

[WxUSAF]

I’ll wait until Saturday morning or so and NAM 3k is in range, but I’m really skeptical of ZR north of like EZF (and maybe even south of that). Really would think snow to sleet to storm over.

[Weather Will]

WB 6Z EURO AI

[TSSN+]

1 minute ago, Weather Will said:

WB 6Z EURO AI

Looks like basically a hold. 

[SomeguyfromTakomaPark]

2 minutes ago, TSSN+ said:

Looks like basically a hold. 

Toggling the 850 anomaly it looks like a noticeable shift colder.

[Ji]

Looks like basically a hold. 

It ticked south and colder. Primary wasn’t as far north

[TSSN+]

1 minute ago, SomeguyfromTakomaPark said:

Toggling the 850 anomaly it looks like a noticeable shift colder.

A little ya dc increased like 1” of snow that run. 

[nw baltimore wx]

Last night’s 0z on top.

6z below. Thanks, Will!

[Terpeast]

3 minutes ago, SomeguyfromTakomaPark said:

Toggling the 850 anomaly it looks like a noticeable shift colder.

Small tip on interpreting 850 anoms - our climo minimum is -4C, so even if it's "anomalously warm" by 3 C, it's still -1

May not be worth much since it's an AI model and I don't trust thermals (yet), and there are other levels where the warm nose could be strongest (probably 750-800 mb). Mesos will help us figure that out as we get closer in.

[Weather Will]

WB 6Z EURO 1am Sunday, 7, 10, 1 pm, 4, 7, 10

[SomeguyfromTakomaPark]

6Z euro looks to be colder too.

[mappy]

At hr81, euro is a little drier, and/or slowed down by a few hours. Less qpf when comparing runs 

[mappy]

Euro still has that warm nose at 700-850 gets up to me by Sunday afternoon 

[mappy]

Just now, mappy said:

Euro still has that warm nose at 700-850 gets up to me by Sunday afternoon 

About an inch qpf IMBY before any flip 

[aldie 22]

3 minutes ago, Weather Will said:

WB 6Z EURO 1am Sunday, 7, 10, 1 pm, 4

WV panhandle looks to be the spot on the euro...im holding on for dear life at 4pm

[mappy]

I’m terrible at analysis but it’s a region wide hold, def sleety in the afternoon Sunday for 95 east