John1122

The GFS went full on coastal craziness on us for Nashville and points east. We'd be fighting some ground temps for sure. and the height is in the afternoon, but the sun angle this time of year is similar to early February.  The Euro is well NW during this time with a major storm from Oklahoma to Michigan with some snow showers here chasing the back end. There was a member of the EPS that showed a similar event last night.

3 minutes ago, Carvers Gap said:

Man, we go to the Sanibel vicinity most summers.  Really like that area.   Definitely been eyeing the time frame next week.   Very strong, early season trough w energy rounding the base...lake effect machine gets cranking with most solutions.

We're going to Marco Island. Leaving Wednesday evening next week. A week ago the forecast high was 86 upon our arrival. Now it's changed to 73/56.

Euro snowfall map for next week. Obviously still a ways out and the accumulation is a crapshoot at best. But 43 of 50 members of the EPS at 00z had some form of dusting or more for the various parts of the valley. Most were clustered like this snowfall map but some were more West Tennessee based, of member mauled NW Tn up through SWKY.

More important to me is the significant cold being modeled. My cold November stance is well noted and this cold snap is just what I was hoping for. Hopefully it comes to pass, even though I'm going on vacation to SW Florida next week and temps when I arrive there are forecast to be 15-20 degrees below normal. The normals where I'm going is 83/64 so probably looking at 70/50ish.

Looking more and more like the first lower elevation flakes of the season are going to be possible somewhere over the valley early next week. Clarksville to Nashville and points East look most likely right now, to see snow showers. The Euro and GFS are putting out .5-1.5 on the Plateau/SEKy/SWVA with 1-3+ inches in the mountains.

Looking back on reports about the Euro weeklies from around 4-6  weeks ago, it was also depicting zonal flow towards the end of its run then.  

This looks to be the actual result for the time frame.  

I'd actually say most of the area here is now at peak as well after taking a look around yesterday evening. It's crazy how fast it has moved. The entire process of change has happened in about 10 days.

This is looking down in the 1300-1700 feet range yesterday evening from around 2800 feet. You can see much more color looking down on it.

It's had that look off and on for a few days now. Reel her in GOOFY!!

My area is at peak above 2000 feet and probably a week from peak below that. The heavy rain tomorrow may end the peak early above 2000.

11 hours ago, jaxjagman said:

Here John,went through my links, knew i had something better

snow/ice

For whatever reason, that is the site that won't work for me. It gives a security error no matter which browser I use to open it. Says the security certificate is figured incorrectly.

It's  raw day today. 44 degrees and NW flow showers passing over. 

The NASA climate scientist who's panel I attended this summer was bullish on winter weather during this low solar period. She said the minimum was still likely 12-18 months away. Which would put it at June 2019/January 2020. She tied the low solar activity into the  the little ice age and  the year without a summer. She said this minimum was an extremely low minimum compared to the recent past events and similar to those from long ago. So at least in her mind, there's a decent impact on winter weather with low solar activity. Of course the entire global climate conditions have changed since then, so no telling what the ultimate result would be to the very low minimum.

Greatly enjoyed that, Flash, hopefully you grab an A on the overall forecast next spring!

The AN temps the ensembles were forecasting for the 1st week of November have turned the corner. Good way to start the month if we can reel this in.

A very simple take on winters in the region is this in my experience. In the 1950s-1970s it snowed often in winter. It was often cold. It didn't seem to matter what state certain drivers were in, the most favorable ones (NAO/AO/PNA) were often favorable.   Heck, 1965-66 was a strong El-Nino, which is usually tough for winter here, that didn't even matter. It was a frigid/snowy winter. 

The 1980s began to transition away from that. It snowed and was cold in the first half of the 80s but it became less frequent in the 2nd half. From the late 1980s until the late 2000s good winters were the rare exception rather than the rule they were in the 1970s and decades prior. Since 2009-10 it's been feast or famine. We will have 2-3 colder winters with snow chances, then 2 winters where you chase individual flakes.

Just saw Carver's post further explaining the QBO. Thanks Carver!

After looking at the more extensive data I can't find a true pattern of -NAO/QBO relationship.

1955 strong/moderate -NAO Jan/Feb'/Mar. QBO went from -9 to -5 to -1 to +1 D-M

1956 moderate/strong -NAO Feb. QBO went from +3.8 to -3.3 D-F.

1958 JFM deeping -NAO from Mod to Strong but steady +QBO the entire time

1959 J mod -NAO but steady -QBO

1960 mega -NAO Jan-Feb (oddly not nearly as - in Mar when it snowed so much) QBO was in 6th consecutive + month by Jan but was falling towards negative from it's peak.

1961 mod D -NAO QBO in it's 6th month of steady +.

1963 mod/strong -NAO JFM  QBO in a steady negative state.

1963-64 mod/strong -NAO DJF QBO in a 6 month steady + state

1965 mod -NAO  FEB, QBO changing from + to -.

1966 strong -NAO JF QBO steady -.

1967 mod -NAO J. QBO steady +.

1968 mod -NA0 F QBO steady -.

1968-69 DJF mod/strong -NAO  rapidly weakening -QBO

1970 strong -NAO J rapidly weakening +QBO

1970-71 DJ mod -NAO rapidly weakening -QBO

1975 mod -NAO FM steady -QBO

1976-77 DJF mod -NAO rapidly strengthening -QBO 

1977-78 DF mod -NAO with J being +NAO +QBO rapidly strengthening.

This is where I got to from my prior post. 

By looking at that, the NAO was - when the QBO was heading from - to +, when it was heading from +  to -, when it was steadily +, when it was steadily -, when it was gaining strength both towards + and -.

There was a longish stretch from the late 80s to 2009 when the QBO was - for each of the relatively few -NAO months we had during that time that could lead to it looking like a stronger indicator than it is imo. The 50s-70s were prominent -NAO years for whatever reason and the state of the QBO didn't seem to matter in those years. 

As I mentioned in my prior posts, the sheer volume of deeply -QBO months that don't result in a -NAO makes me skeptical about it's connection to the NAO.

5 hours ago, jaxjagman said:

https://www.esrl.noaa.gov/psd/data/correlation/qbo.data

Thanks Jax!

Great post Carvers  but we will indeed have to disagree on the QBO. I look at it more this way, there were 54 months of -QBO during DJF for the last 38.5 years. Only 12 out of 54 saw a moderate -NAO average out for a winter month and 12 is debatable as I point out below regarding Jan 85. When you throw in the fact that it was almost equal from + QBO years, it just doesn't seem like a strong indicator to me.  So a -QBO in winter saw a 20 percent rate of -NAO coinciding with it. +QBO saw a -NAO 12 percent of the time.

As Jeff pointed out, times of change may be a factor. January 85 it flipped from - to + and in reverse, the NAO flipped from + to -.  I even list 85 as -, because technically it was at -.30, but it was + for the latter half of January and rising rapidly during that time. So it could be argued that the split was 11-7-1 on the QBO years that produced -NAO, as the QBO was neutral essentially in Jan 85. 

I'll look later and see if I can find a QBO reading for the 1950s - 1970s. Not been able to find one so far. Not really sure why the -NAO was so common before and why it became so rare over the last 28 years vs the prior 40.

The ENSO state and the PDO look like they could shape up for Western blocking. Which tbh, is my favorite blocking. The NAO is nice too, but it's not the be all/end all for winter weather here. We can get it done without a -NAO. We have a lot more trouble getting it done with a -PNA. 

I'll throw this out there about the NAO/QBO. The QBO was deeply negative in winter 2015 and winter 2018. Now we had cold weather around those winters, but what we didn't have was the -NAO. The cold was Pacific driven.

 As a matter of fact, the last time the NAO was below -1 for a winter month was January 2011.  The QBO at 30mb (the measure the mets in the video) had left negative territory and was climbing into positive territory that fall into that winter. 1984 into 1985 is another year that saw it rise from negative to positive heading into winter.  When it flipped positive January 85 had a deeply negative NAO. I don't really see a strong connection between the QBO and blocking. Even when it's negative we seem to get no blocking much more than we get blocking. When it's positive blocking seems  hard to come by as well, but not much more so than when it's negative.

Looking at the best -NAO months in winter we find the following since 1979 when the QBO 30mb measurements start from CPC.

January 1979 -2.12 NAO  + QBO  

Feb 1979 -1.20 NAO + QBO 

Jan 1980 -1.38 NAO - QBO 

Jan 1982 -1.55 NAO - QBO

Feb 1983 -1.03 NAO + QBO

Jan 1985 -2.38 NAO - QBO

Feb 1985 -1 NAO + QBO

Feb 1986 -1.58 NA0  + QBO

Jan 1987 -1.85 NAO - QBO

Feb 1987 -1.27 NAO - QBO

Dec 1989 -1.15 NAO  - QBO

Dec 1995 -1.65 NAO - QBO

Dec 1996 -1.40 NAO - QBO

Jan 1997 -1.08 NAO - QBO

Dec 2009 -1.88 NAO  - QBO

Jan 2010 -1.89 NAO - QBO

Feb 2010 -2.63 NAO - QBO

Dec 2010 -1.80 NAO + QBO

Jan 2011 -1.53 NAO + QBO

So out of the 19 moderate to deeply Negative DJF months since 1979 it's a 12-7 split in favor of the -QBO. There were also 42 DJF months with a -QBO that didn't produce a NAO of more than -1 for the month. Sadly, the -NAO is just uncommon here since the  80s ended. Since 1990 we've had the NAO average more than -1 8 times in any DJF month. By contrast from 1960-1987 we had 37 DJF months total with the NAO at -1 or less on average for those months. In the 50s, 60s, 70s and 80s it happened 8 or more times each decade. I'm not sure if there's some long term pattern of -NAO vs + NAO in winter or not, if there is, I hope it doesn't stay in it's mostly + phase for another decade.

The GEFS backed down on the strength of the early November warmth in the SE that it was showing yesterday at this time.

12z yesterday.

Same time frame today.

East coast ridging yesterday 

Today the 588 dm over Florida is not there.

Ridge is brief, retreating NE and Pacific ridging is pushing the trough eastward.

https://journals.ametsoc.org/doi/full/10.1175/JAMC-D-16-0249.1

Try this Jax, similar subject matter.

The ridge looks to be breaking down after a week or so in November. We need it to be overblown and out of here. I want no part of a warm November for the reasons I've posted about many times.

The GFS just cooked up a high mountain heavy snow event next week from basically a miller A system. Mostly confined to North Carolina but a few inches at Roan Mountain and those areas would be on tap.

October 1963 was very mild as well. 80s all the way up until late October. BNA and Crossville were 4-6 degrees above normal for October. BNA was near 90 as late as October 21st.Transitioned to slightly BN for November in the area and then all the winter mentioned above happened.

1963-64 was one of those legendary stretches of early winter in the Valley, 4 inches of snow fell on November 29th. December was bone chilling cold. My area had 15 inches of snow December 22nd and 23, then 8 more on December 31st. 26 inches for the month. There was a -8 degree low during the month as well that led into those snow events. 5 more fell on January 1st. So in a 10 day period two double digit snowfalls fell here. There was 10 inches of snow on the ground on Christmas day and 14 inches on the ground on New Years day. There would have been more than 14 on New Years day but it got to 58 degrees on December 26th and melted the snowpack down to 2 inches from the 10 that was on the ground on Christmas day. Another snow fell on January 12, this one 4 inches. Then it turned mild a few days later and there wasn't another significant snow until late February. 7 inches on the 28th. By March 4th it was in the lower 70s.