Math/Met

Big flakes in Greeneville right now.

http://www.resortcams.com/webcams/greeneville-tn/

1 hour ago, John1122 said:

Can't find a map but the 1-28-98 event saw 21 inches fall at Wise with a max depth of 16 inches. Missing data at Mountain City with 9 inches on the ground 2 days after the event.  Erwin has 9 inches falling with 3.05 inches of QPF. No idea if that snow amount is accurate. It also shows 9 inches on the ground the day that 9 inches fell, 6 inches on the ground the next day. Missing data in Abingdon with 10 inches of snow falling recorded.  Tri recorded 2.3 inches of precip but doesn't have snowfall listed/missing data. Elizabethton recorded 18 inches.  5 inches at Gatlinburg. 26 inches at Mt LeConte.

Lots of missing data for NE Tn sites is common for the 90s. Elizabethton looks like it has the least missing data with 18 inches of snow recorded on around 1.9 inches of qpf.

I've noticed that too. It's hard to find reliable weather data for this area. 

The MRX weather calendar lists the following for that date. The mountain totals seem realistic, but the valley is underestimated. 

Quote

Snowstorm hit the area in 1998. 24-48" fell in the mountains, 5-10" in the valley. 1 died.

The UT experiment station in Greene County had archived weather data available online a few years ago. I remember seeing a hand written record from that location with 18 inches listed as the snow depth for the day after the storm. I’m sure there was some melting and compaction, so I feel really confident that many areas had around 20 inches.

15 minutes ago, Carvers Gap said:

Is this the 98 snowstorm?

https://fox41blogs.typepad.com/wdrb_weather/2013/02/february-1998-the-forgotten-snowstorm.html

The Northeast TN storm was 1/27/98.

The January 1998 storm was discussed in the following link (it is primarily about 2009). 

https://www.highknoblandform.com/2010/01/mega-disaster-storm-of-december-2009.html

1 hour ago, tnweathernut said:

3+" per hour for over 6 straight hours.  I remember thinking at the time i'd likely never see anything like it again.....   I would have given anything back then to have the technology and social media presence we have now.  the videos would have been awesome.  As a side note, local forecasters NEVER bit on a big snow and were always playing catch up.  The power went out in my part of JC and there was about 6-7" of snow on the ground (either 5:15 or 6:15).  I remember the time because WJHL (Mark Reynolds) was on TV saying don't be surprised if we see some 6-7 inch reports, then poof.......power went out.  We ended up with over 20" and the sounds of transformers blowing all over JC.

1 hour ago, DownNDirtyTN said:

I remember that storm as being kind of out of nowhere. Maybe I just didn't pay enough attention to the weather then but I'm pretty sure we got like 20" of snow or something close to that and if they were calling for snow it definitely wasn't that much to my recollection. The main takeaway I had was that it came hard, fast, and the flakes were gigantic. It was the hardest I've ever seen it snow in my lifetime. 

That’s how I remember it as well. I’m pretty sure that the original forecast was for a rain/snow mix changing to rain by the afternoon. It actually changed to rain in Greeneville, but it changed back to snow when the heavier precip developed.

I’m not sure that the NWS was ever truly aware that such a major snowstorm was occurring. It was a fairly localized event and no social media to get reports. By the time the warnings were finally issued, we had already exceeded the totals mentioned in the warning.

50 minutes ago, Carvers Gap said:

Definitely a decade with some really big snows, but I think less "extended winter" patterns and less consistent snows.  I remember UT opened their outdoor pool one winter during January.  So yeah, plenty of days to get outside.  And I might be a bit skewed as my family is in Kingsport, and we missed the 98 storm.  I like to tell tnweathernut that we had a guy who missed a week of work in 98.  We got like two inches here in Kingsport (maybe 2") that was gone by mid-day.  JC received like two to three feet!  He kept telling folks that he couldn't get out of his driveway, that his power was out, and that trees were down all over his yard.  We thought he was just taking some time off.  Nope.  They got absolutely hammered.    This was before social media where folks would have been talking about it.  I think my work schedule prevented my from seeing the local news for a few days.  We felt terrible once we knew how much damage he had received.  Johnson City will sometimes get these weather systems that just sit over Buffalo Mountain.  During summer it results in torrential rains.  During winter it results in big snows.  The Methodist camp had to be moved due to flash flooding that knocked buildings off of their foundations.  And to this day, I hate that I missed the winter of '96 here in Kingsport.  I was in Knoxville, and it wasn't a shabby winter there either.  But I kept coming home to visit family, and the parking lots were full of towering mounds of snow after two heavy snows during three weeks.  So, I only have '93 in my back pocket out of those three big storms.  Now, Kingsport did get a big snow the year before or just after the big JC snow.  I think we got 18" on the west end of town and 5" on the other end...depended on if you were down wind of the industrial areas.  I think the winters of the past couple of decades are similar to the 80s excluding 84-85. We are long overdue for a region wide big snow of 12" plus...long overdue.

The 98 snowstorm in NE TN was probably my favorite weather event of all time. I didn’t realize that Kingsport missed it. I know Greene County, Washington County, and other spots along the mountains got hammered.  Incredible snowfall rates with that system and by far the biggest snowflakes I’ve ever seen (in person or video). I really wish someone had video from that event. I’ve looked several times but never found any footage.

59 minutes ago, Carvers Gap said:

I agree with all points.  If UT can land Wright and Russell in February, he has set a great foundation.  SEC size and speed.  Hey, I ran into a lady who lives near Camp Creek while eating Sunday evening.  Among other things, she basically said half jokingly that everyone gets new lawn furniture(the neighbors) with each mountain wave event...and she even knew the term, mountain wave!  

True, you don’t see a lot of lawn furniture or Christmas decorations in that area.  My family learned our lesson with Christmas decorations the first year we moved to southern Greene Co. We tried to reinforce them, but it still didn’t work.

I think MRX and local TV meteorologists have done a good job in recent years of explaining mountain waves.  When I was a kid, people in that area just referred to it as the “south winds”. At that time, there could be 80+ mph winds in Camp Creek and there wouldn’t even be a Wind Advisory issued.  It is such a localized event and there wasn't a wind tower yet, so MRX didn't even know about it.

23 minutes ago, Carvers Gap said:

I think that is correct.  Losing him will rank up there with some great misses in recruiting with respect to Tennessee football...Spurrier a similar situation.  It was remarkable what Lawrence was doing with the football last night...great decisions, strong/accurate arm, limited mistakes, made big plays, reading Bama's multiple look defense/blitzes, and was cool under pressure.  Not to mention that Higgins and Rogers both played their high school football in Knoxville.  Ugh....that hurts just typing it.  But Clemson showed how to beat an SEC defense...spread them out and put your best receivers running into the middle with LBs covering them...read or heard that this AM.  Very true.  But it doesn't hurt to have Sunshine(compliment intended) slinging it either behind a stellar offensive front.

I’m not a UT fan, but I was thinking about that last night. Tennessee would be a completely different team the next couple years if they had those guys from East TN. You could also add Mays (Georgia) to that list.  On the bright side for you guys, I think Pruitt is a major upgrade and the state of TN seems to be producing a lot more talent these days.  

3 hours ago, Carvers Gap said:

Stings a bit knowing that Lawrence grew up as a TN fan.  Butch Jones didn't want to adapt to his skills.  Weather looks nice out there in Cali though.

Didn’t he grow up in the Tri-Cities area before moving to Georgia? It would have been fun to watch him play locally in high school if he would have stayed here.

2 hours ago, John1122 said:

I'm going to have to go to Camp Creek during one of these events. It's probably the strongest low elevation winds you can experience without being in a tornado/storm/hurricane.

It would be worth the trip. I was out there a few years ago when there was a 92mph gust. I wish the wind tower was there for the 2004 event, it was crazy. It had to be close to 100mph.

The rain moved in pretty quick tonight compared to most mountain wave events. Usually the downslope wins the battle for a longer period. Large areas of precip usually decreases MW winds significantly if it holds together. 

I went to Camp Creek this afternoon. There was an 81mph gust just before I got there. Only gusting in the 70mph range while I was there. I'm still expecting higher gusts after dark.

Camp Creek is already gusting to around 72mph. That should continue to increase this evening. 

You guys do a great job with the long range discussion. I enjoy reading your thoughts.

I just wanted to give a quick update on the mountain wave event for tomorrow. I’ll post some updates in the obs tomorrow. Everything still looks on track for a significant mountain wave event. MRX issued a High Wind Warning along the mountains, which is probably the right call because winds should easily meet the criteria in several locations along the mountains. I wouldn’t be surprised if there are some strong gusts in a few spots outside of the warning.  For example, parts of southern Washington County can get hit pretty hard with these events too.

A major mountain wave event is possible for Thursday into early Friday morning for the foothills of East TN.  Models are consistent with bringing a southerly 60-70+ kt LLJ across parts of TN and KY, with the strongest core of the LLJ just to the west of the mountains. This puts East TN mountains in a favorable spot. Winds below 850mb are from a southeasterly direction and that will establish the cross barrier flow within a stable boundary layer.  This system and forecast soundings look like a classic set up, so I think damaging wind gusts are likely along the favored mountain and foothills locations.  

1 hour ago, Blue Ridge said:

Incredibly thick fog has developed within the last hour. Temp is hovering around freezing. This may spell trouble in the morning.

Freezing fog has formed a thin layer of ice on cars.

9 minutes ago, John1122 said:

It's snowing pretty hard here, quarter sized flakes roughly. It looks like it'd be really coming down just south of me. Are you under heavy returns at all?

It's doing the same in Greene Co at the moment. Quarter sized flakes. The radar looks good. The 06z NAM has this hanging around eastern areas until about 15z.  

Congratulations to everyone who received heavy snow accumulation. I know it didn’t work out for everyone (including me), but it was an interesting system to track. There’s always something to be learned from each system.  I’m hoping some of us can get a small consolation prize tonight.  It looks like lift is increasing and we are starting to get better saturation in the snow growth zone.

22 minutes ago, tnweathernut said:

I’d bet a dollar to a donut, @Math/Met   is searching for a mountain wave event with the look of the system on the 14th and 15th......

I've been too focused on the current system,  but you are right. The 12z GFS would have potential for a major mountain wave event with that system. 

Euro text shows KTRI with 13.6 inches. That’s based on ratios that are around 8:1 for the majority of the storm and end around 10:1. The actual ratios would probably be a little lower than that, but I don’t have soundings to analyze.  It also has the high temperature for today at 43, so we can see how that verifies this afternoon. 

1 hour ago, Math/Met said:

To be honest, it does concern me that it shows up on the models.  I still don’t see much of a surface response to potential downslope on the surface wind or temperature products, so it could be overdone. But models are trying to depict something happening in those areas, so it’s hard to completely dismiss that. I have a lot less experience with this type of setup compared to true downslope events.

To expand on this discussion. There could be a shadowing effect right along the mountains that decreases precip. I’m not sure that it would be as expansive as some models are showing. Possibly a narrow region right along the mountains. There could also be an area just northwest of that where surface convergence would actually act to increase lift and enhance banding of precip. That’s just my thoughts.  As you all are well aware, trying to predict wind flow through and over complex terrain is not easy.

1 hour ago, tnweathernut said:

I see MathMet lurking, hope you are doing well.  We all probably MBY focused on some level, but I’d like to know if you have an opinion of the mesoscale models showing the downslope this AM?  If your prior opinion still stands no worries about a response,  I know you have to be busy....lol

overall modeling seems to be converging on a heavy northeast (maybe much of east) TN snow.  It’s funny I’m almost obsessing about the trailing piece of energy as much as the main system.  I find that discrete feature fascinating!

To be honest, it does concern me that it shows up on the models.  I still don’t see much of a surface response to potential downslope on the surface wind or temperature products, so it could be overdone. But models are trying to depict something happening in those areas, so it’s hard to completely dismiss that. I have a lot less experience with this type of setup compared to true downslope events.

0z Euro text data(from f5wx.com) for Johnson City has ratios around 8:1 with a total of 10.1 inches. KTRI and Greeneville are about 9 inches.  The ratios might be slightly lower than that, but it gives you a general idea.

Generally 4-6 inches in NE TN based on the Euro text data. Higher totals as you get closer to the mountains.  The area near the mountains where we were concerned about having downslope issues may end up being the favored spot based on that Euro run.  But as John said, that run had much less precip over northern areas.   

4 minutes ago, John1122 said:

The ratio'd map at Pivotal has Tri at 9 inches. So it seems to work pretty well based on your math, which I trust more.

I’m using F5wx text output, but it looks reasonable compared to soundings.

Looking at the text output for the 00z FV3 at KTRI. It has .42 falling as snow with ratios about 7:1.  Then another .67 with ratios increasing to around 10:1 as it moves out.  That brings the total of 9.7 inches. Based on soundings, those ratios might be slightly too high but probably not too far off.