January 2021 General Discussions & Observations Thread

[Rjay]

The Euro drives a low into the lakes then redevelops into strong coastal.  Another run, another solution.  200+ hours out.  

 

 

[Rjay]

Pretty odd solution but that's to be expected I guess will a big west based -nao, deep trough in the west and a 200+ hour out op run 

 

[wdrag]

Good Sunday morning everyone, Jan 17.  No insight except my own interp of what the models are trying to say up here.  No big deal til the 25th and even then, quite a bit of uncertainty, including ptype along I80-LI. 

 

I84 corridor Today-Tuesday... a few flurries and maybe one or two short periods of minor accumulative snow showers, especially Poconos Monday-Tuesday where dustings are probable.

 

I84-I80 corridors including LI Wednesday morning-early afternoon including LI: COLD. A period of flurries seem likely or even minor accumulative snow showers.

 

I84-I80 corridors including LI Thursday afternoon-early Friday: A period of flurries or minor accumulative snow showers, except possibly sprinkles-light rain for LI.

 

25th-26th: No 06z V16 as of this writing and the 06z op was scary dry. NAEFS has a widespread light event of snow or ice I80 northward (Rain LI?). Not convinced yet of the NAEFS amounts of 0.4" melted. Could be less.   Have a good day and let's cross fingers for something.  

[CIK62]

The next 8 days are averaging 34degs.(29/39).          Making it 29degs., or -3.0.

The last week of January is averaging 26degs.(21/31).[GFS,0Z]       Big increase in the average and we would greet February at 50degs.        All models have some snow 25th./26th.*****        No sub-20 T till the 27th./28th.

06Z Run is warmer still>>>  *****No storm phasing either.     SO SORRY

36*(70%RH) here at 6am, breezy.       37* by 9am.       38* by 10am.

[donsutherland1]

Morning thoughts...

Today will be partly cloudy. Temperatures will likely reach the lower and perhaps middle 40s in most of the region. Likely high temperatures around the region include:

New York City (Central Park): 44°

Newark: 46°

Philadelphia: 46°

A strong cold front could move across the region late in the week bringing a period of light snow or flurries.

[bluewave]

We are doing better than Northern New England with cold temperatures relative to averages. It was a tie for the warmest first half of winter at Caribou. BTV finished at the 4th warmest. NYC is further down the list at 19th warmest.

Time Series Summary for Caribou Area, ME (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Jan 15	Missing Count
1	2021-01-15	25.0	0
-	2016-01-15	25.0	0
2	2011-01-15	24.3	0
3	2007-01-15	23.6	0
4	2002-01-15	23.5	0
5	1997-01-15	22.8	0

 

Time Series Summary for Burlington Area, VT (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Jan 15	Missing Count
1	2016-01-15	34.7	0
2	2007-01-15	33.2	0
3	2002-01-15	30.9	0
4	2021-01-15	30.0	0
5	1997-01-15	29.4	0

 

Time Series Summary for NY CITY CENTRAL PARK, NY
Click column heading to sort ascending, click again to sort descending.

Rank	Ending Date	Mean Avg Temperature Dec 1 to Jan 15	Missing Count
1	2016-01-15	45.7	0
2	2007-01-15	44.5	0
3	1932-01-15	41.9	0
4	2002-01-15	41.7	0
5	2012-01-15	41.2	0
6	1983-01-15	41.0	0
7	2013-01-15	40.7	0
-	1950-01-15	40.7	0
8	1995-01-15	40.6	0
9	1890-01-15	40.2	0
10	2000-01-15	40.1	0
11	1998-01-15	39.9	0
-	1992-01-15	39.9	0
-	1985-01-15	39.9	0
12	2020-01-15	39.8	0
13	1972-01-15	39.7	0
-	1937-01-15	39.7	0
-	1892-01-15	39.7	0
14	2005-01-15	39.6	0
-	1991-01-15	39.6	0
15	1966-01-15	39.2	0
-	1913-01-15	39.2	0
16	1975-01-15	39.1	0
-	1924-01-15	39.1	0
17	1997-01-15	39.0	0
-	1980-01-15	39.0	0
18	1933-01-15	38.8	0
19	2021-01-15	38.6	0

[snowman19]

6 hours ago, Rjay said:

Pretty odd solution but that's to be expected I guess will a big west based -nao, deep trough in the west and a 200+ hour out op run 

 

If there’s a deep, full latitude trough on the west coast instead of off the west coast for this storm, people aren’t going to like the results here as far as snow, even with the blocking. Plus you still have a raging fast northern stream at that point....

[snowman19]

1 hour ago, bluewave said:

The GFS and several EPS members look like they are going for more of a spring snow set up than what we usually see during the winter.  We normally don’t get big winter snowstorms with such a pronounced trough out West. But it has happened during the spring. April 1982 was a famous example. 
 

GFS forecast

April 1982

 

Exactly. That setup might work in March with the shorter wavelengths, but as far as that look (deep, full latitude trough on the west coast instead of off the west coast) producing a big snowstorm next week, along with the northern stream still screaming across the CONUS....color me skeptical 

[snowman19]

@bluewave @donsutherland1 I know @Rjay and others don’t like BAMWX and I can understand why at times, but they have a point here. Yet another modeled “cold” period turning way warmer as we move closer in time. Now, 1/18-1/31 doesn’t look so cold and snowy anymore. GEFS and EPS doing an about face yet again. The beat goes on....

 

 

[Allsnow]

1 minute ago, snowman19 said:

@bluewave @donsutherland1 I know @Rjay and others don’t like BAMWX and I can understand why at times, but they have a point here. Yet another modeled “cold” period turning way warmer as we move closer in time. Now, 1/18-1/31 doesn’t look so cold and snowy anymore. GEFS and EPS doing an about face yet again. The beat goes on....

 

 

A 2-3 degree difference in temps a week out isn’t exactly can kicking. The overall theme is there for colder weather. 

[Allsnow]

13 minutes ago, snowman19 said:

Exactly. That setup might work in March with the shorter wavelengths, but as far as that look (deep, full latitude trough on the west coast instead of off the west coast) producing a big snowstorm next week, along with the northern stream still screaming across the CONUS....color me skeptical 

That’s not what he said at all. You continue to speak in absolutes which gets you in trouble all the time. How’s the Niña February looking? 

[snowman19]

5 minutes ago, Allsnow said:

That’s not what he said at all. You continue to speak in absolutes which gets you in trouble all the time. How’s the Niña February looking? 

Not speaking in absolutes at all. And how good is the Niña February looking? About as good as the SSW bringing epic cold and snow here. Or “MJO phase 8!” Or the collapsed Niña by January. Lol I’m going to bring this post back up should we be deep in the throws of a canonical La Niña pattern next month 

[Isotherm]

My brief thoughts w/ attendant illustration. The difference in outcomes b/t the 00z ECMWF and yesterday's 12z run (and by extension, other guidance), is largely predicated on the behavior of the short wave trailing the target short wave. Yesterday's solutions maintained significant magnitude/coherency w/ the trailing short, thereby keeping the front-running target short wave deamplified, and thus unlikely to "connect" with the Canadian PV lobe. The off-West Coast s/w trough is a key ingredient as to raising the putative ceiling on the downstream outcomes, as it provides the wave spacing to ensure deamplification until the "right" time, additional ridging in the Rockies, which aids in phasing and amplification at the most propitious times. The new set of solutions would still yield a winter event in the Northeast, but a lower-ceiling event. Which solution has more credence? The answer at this point is stochastic and effectively anyone's conjecture. The macro-scale features, inclusive of a westward retrograding, slowly degrading blocking structure, concomitant 50/50 positioned vortex, set condition precedents which significiantly increase the probability of wintry weather in the Northeast, as has been targeted for the month. The question as to the specifics of the actual system will be a function of the behavior of the incoming Pacific short waves. For snow enthusiasts, the solution to desire is a return to a larger trailing short wave which deamplifies the front-running initially, obviating early phasing. Full-latitude Western trough solutions would yield lower ceiling, energy transfer/SWFE type outcomes.

 

[donsutherland1]

2 hours ago, snowman19 said:

@bluewave @donsutherland1 I know @Rjay and others don’t like BAMWX and I can understand why at times, but they have a point here. Yet another modeled “cold” period turning way warmer as we move closer in time. Now, 1/18-1/31 doesn’t look so cold and snowy anymore. GEFS and EPS doing an about face yet again. The beat goes on....

 

 

A few things, from my perspective:

1. I didn’t believe that the last week of January would be frigid. It will likely be solidly colder than normal, but if one is looking for a genuine Arctic blast, that does not appear to be likely. 

2. There will likely be some opportunities for snowfall. But in late January, an AO-/PNA- pattern generally does not produce major snowstorms for the Philadelphia to Boston region. Once wave lengths shorten, one sees such outcomes on a more frequent basis (typically during the second half of February and onward). 

3. The modeled pattern on some of the guidance is unusual for late January in that some ensemble members suggest a significant snowfall. I’m skeptical of that idea from this far out. If one were less than 72 hours out, that might be different.

For purposes of illustration, below is a scatter diagram for NYC's days with 4" or more snowfall during the January 20-31, 1950-2020 period for the AO/PNA:

[LibertyBell]

21 hours ago, Stormlover74 said:

I had an early dismissal but lived down in Jackson at the time. I believe it started snowing around 10am

yup early dismissal here too, about an hour before regular release time from school

[LibertyBell]

21 minutes ago, donsutherland1 said:

A few things, from my perspective:

1. I didn’t believe that the last week of January would be frigid. It will likely be solidly colder than normal, but if one is looking for a genuine Arctic blast, that does not appear to be likely. 

2. There will likely be some opportunities for snowfall. But in late January, an AO-/PNA- pattern generally does not produce major snowstorms for the Philadelphia to Boston region. Once wave lengths shorten, one sees such outcomes on a more frequent basis (typically during the second half of February and onward). 

3. The modeled pattern on some of the guidance is unusual for late January in that some ensemble members suggest a significant snowfall. I’m skeptical of that idea from this far out. If one were less than 72 hours out, that might be different.

we rarely get those kinds of arctic outbreaks here anymore so I didn't think it likely either.  Highs near freezing are a good possibility though.

why people like extreme cold is beyond me

[eduggs]

12 hours ago, Rjay said:

To be fair I didn't really look into the details until now.  The low in Canada is just a vigorous northern stream s/w.  It's not like a storm developed over the plains and drove into the block.  So I guess it's plausible. 

 Btw, I'm legit laughing at breaking down a day 9/10 op run but it's always fun to learn I guess.  

Yes the models show an active northern stream, and it would be surprising if a southern stream low went north of the Lakes with the current flow regime over the Northern Hemisphere. The point I was trying to make is that if one of the primary models shows a southern stream low moving through the Lakes at day 9, it's probably a valid solution. It doesn't mean it's likely to happen, just that it could happen. No, lows don't drive into blocks. But lows form and move in concert with movement of upper level features. So in this hypothetical scenario, if there's a cutter low, the modeled "block" probably moved or disappeared.

[LibertyBell]

2 hours ago, bluewave said:

The GFS and several EPS members look like they are going for more of a spring snow set up than what we usually see during the winter.  We normally don’t get big winter snowstorms with such a pronounced trough out West. But it has happened during the spring. April 1982 was a famous example. 
 

GFS forecast

April 1982

 

my favorite pattern is a trough on the west coast and a trough on the east coast with a ridge in between- it looks like the Greek letter Omega

 

[eduggs]

44 minutes ago, snowman19 said:

Not speaking in absolutes at all. And how good is the Niña February looking? About as good as the SSW bringing epic cold and snow here. Or “MJO phase 8!” Or the collapsed Niña by January. Lol I’m going to bring this post back up should we be deep in the throws of a canonical La Niña pattern next month 

I like Walt's approach. He doesn't really talk about weeklies, ENSO states, climate indices etc. And he generally does not look past about 10 days. He doesn't seem to talk a lot about "pattern". He just seems laser focused on tangible threats for the local area. Because for us, weather is a very local phenomenon. Apologies to him if I'm misrepresenting him. I just really prefer this approach to the long-range twitter crowd. It keeps hopes and expectations much more realistic.

[NEG NAO]

35 minutes ago, donsutherland1 said:

A few things, from my perspective:

1. I didn’t believe that the last week of January would be frigid. It will likely be solidly colder than normal, but if one is looking for a genuine Arctic blast, that does not appear to be likely. 

2. There will likely be some opportunities for snowfall. But in late January, an AO-/PNA- pattern generally does not produce major snowstorms for the Philadelphia to Boston region. Once wave lengths shorten, one sees such outcomes on a more frequent basis (typically during the second half of February and onward). 

3. The modeled pattern on some of the guidance is unusual for late January in that some ensemble members suggest a significant snowfall. I’m skeptical of that idea from this far out. If one were less than 72 hours out, that might be different.

EURO is the model of choice because on it's  last run it showed the most logical solution--- the primary LP continues moving towards the block - until it senses the block and then  lets the  energy take over down south of it developing a secondary  and then that secondary moves underneath the block ....BUT according to this run there is only borderline cold enough air in place over the metro so it shows a frozen mix at that point. BUT the primary does initiate a period of snow here before the secondary approaches and slides underneath the metro......

[wdrag]

On frigid weather - enjoyment of-- cause some of us lived through it (we're older but still alive).  

I think there was the 30 days or so of subfreezing weather in NYC that contained the damage of a January garbage strike back in the 60s.  How about pond hockey regularly every winter in the 1960s.  

how about the wonderful chill of the freezer NFL bowl in Jan 82 ...  that was some pretty decent cold. I remember MKE  Jan 1982... two separate super cold episodes out there where electronic means  were needed to keep the oil in your engine from congealing (ie so you could drive to work). and I know one of those shifted episodes into the northeast USA.  BRRRR...   and that's why I own too much long under and outer wear.   Now that was ARCTIC...   The were the days in the northern USA...   

[wdrag]

8 minutes ago, eduggs said:

I like Walt's approach. He doesn't really talk about weeklies, ENSO states, climate indices etc. And he generally does not look past about 10 days. He doesn't seem to talk a lot about "pattern". He just seems laser focused on tangible threats for the local area. Because for us, weather is a very local phenomenon. Apologies to him if I'm misrepresenting him. I just really prefer this approach to the long-range twitter crowd. It keeps hopes and expectations much more realistic.

Thanks... still learning. It's tough to be realistic ...but in forecasting, credibility goes to crud pretty quick if you miss more than the coin flip.  Good to discuss everything as is done on these forums.. helps me see data use that I'm not up to speed on.  

Speaking of which: watch those lapse rates this week and R1(boundary layer RH aka Temp-dew point spreads less than 20F)... We'll have to see if downslope dries out the potential for snow showers all the way down to the city.  I like what I see but models and MOS are pretty dry so that tempers my enthusiasm. Plus the observation process might miss the tiny sub one quarter inch amounts. Making the most out of this winter pattern. 

[NEG NAO]

21 minutes ago, bluewave said:

I think the last time we pulled off a major non-SWFE winter snowstorm with a trough in the West was 2-19-79.

 

ALSO WELL KNOWN AS PD 1............and up to that point NYC had accumulated close to the same amount around 10 inches as they have had so far this season....

[BxEngine]

10 minutes ago, NEG NAO said:

ALSO WELL KNOWN AS PD 2 ............and up to that point NYC had accumulated close to the same amount around 10 inches as they have had so far this season....

Wrong storm.

[NEG NAO]

9 minutes ago, BxEngine said:

Wrong storm.

corrected it to PD 1 - also that was a La NADA season

El Niño and La Niña Years and Intensities (ggweather.com)

[IrishRob17]

45 minutes ago, wdrag said:

On frigid weather - enjoyment of-- cause some of lived through it (we're older but still alive).  

I think there was the 30 days or so of subfreezing weather in NYC that contained the damage of a January garbage strike back in the 60s.  How about pond hockey regularly every winter in the 1960s.  

how about the wonderful chill of the freezer NFL blow in Jan 82 ...  that was some pretty decent cold. I remember MKE  Jan 1982... two separate super cold episodes out there where electronic means  were needed to keep the oil in your engine from congealing (ie so you could drive to work). and I know one of those shifted into the northeast USA.  BRRRR...   and that's why I own too much long under and outer wear.   Now that was ARCTIC...   The were the days in the northern USA...   

Don’t forget frozen car locks, .couldn’t even get the key in the slot let alone turn it. 

[donsutherland1]

Below is a scatter diagram for New York City's daily snowfall of 4" or more during the January 21-31, 1950-2020 period based on the AO/PNA:

[wdrag]

Added from the American Meteorological Society (AMS) Dec 2020 Digital edition.  I think they would like to see this info shared and I think it valuable...especially Lead Time on SVR and Synoptic Scale events. It definitely supports my basis for acting on threads.    This is from page 1125.  

AMS STATEMENTS

Priorities for a New Decade: Weather, Water, and Climate

A Policy Statement of the American Meteorological Society

(Adopted by the AMS Council on 28 September 2020)

 

One to three hours. Our national investment in research and observations has paved the way for severe weather guidance to extend beyond traditional 30- to 60-minute warnings into the 1- to 3-hour time frame. Such guidance could lead to major benefits in preparation and safety. It also raises new questions. How will people respond if they expect to have more than an hour to take action ahead of a possible tornado or a flash flood? How can the probabilities and uncertainties inherent in such guidance best be conveyed? How can schools, workplaces, and other institutions act to support public safety measures in these extended time frames?

Weeks to months. Specific local weather forecasts cannot be issued with accuracy beyond about 10 to 14 days. However, many other types of outlooks have demonstrated accuracy over periods of weeks to months (subseasonal to seasonal periods) when they are presented in terms of probabilities or likelihoods. For example, some periods of increased regional tornado risk

Predicting and respond- ing to such multipronged threats will require new forms of collaboration and data sharing across sectors and disciplines.

 

[NEG NAO]

12Z GFS -redevelops off coast but too warm

[SnoSki14]

The models ramming the block are going to be wrong. I see Miller B or SWFE.

Caveats apply this far out.