Monday, December 10, 2018

Record storm wrap up and what's next??

Wow, so what a storm.. most places saw a foot or more region wide. This is without a doubt the most significant storm this early in the season for our area.

My last posted map was..







Not a bad call, but a little low on the north side and a little low south of Danville. 

I had actually made another map and never uploaded it..

Would have been a little better in some areas but missed the 20 inche totals. 

Actual storm totals..

That northern side was way underdone by everone. This somewhat shows why I didn't really back off Friday when the data sunk south again. Northern edges are always a bear and there were some suble changes that lead to 13.5 in Charlottesville, 11.5 in Richmond and 15-20 in Lexington to Covington areas. 

I ive in Lynchburg and the official total will be 11.7, I had an even 12 or so and region wide 12-15 seems to be the common numbers for our area. 


We are off to a nice start this winter with over 50% of more of the seasonal totals already achieved. 

Outside shot at a little snow and ice late this week but we should be mild until Christmas week. That may be the transition week and then by early January we should be back into a colder pattern. 

In moderate El Ninos-- When you get one storm over 10 inches, you often get a second or even a third. 

09-10, 86-87 and 65-66 were winters that had 2 or more storms over 10 inches in most of our region. 02-03 had a plethora of storms between 3 and 6 inches. 

Meaning, enjoy the break-- we may chatting a lot as the season moves forward. 

Hope you saw my heavy snow video! 



Saturday, December 8, 2018

Double digit snowfall like across much of region Starting Sunday Pre dawn.

This is the type of events that bring meteorologists, hobbyiest and casual weather  fans to the brink of frustration and sanity.   The pattern and set up looked like a snowstorm, but there were several issues that had to be resolved.  This leads to models drifting all over the place and general chaos about the forecast. It seems we have a general idea that 1 inch of liquid, falling as snow like reaches at least to hwy 460 from Blacksburg east through Appomattox. Hence, my totals are going up.

A few points:
Don't rely on your app. Most take one model and spit out what the model says. It is a huge disservice in a winter weather event 5 days out. Accept that the "chance" is there and the details will be ironed out.  It is important to be comfortable with not knowing the exact details.  To me, that's half the fun-- figuring it all out.

Every weather forecaster will be wrong on some aspects of their forecast.  We (They) often focus on their local area and then fan out to areas that they know, but not as well. I have no issues saying I am expect on Lynchburg weather. I do well other places but I know the local nuances better than likely anyone living in the area. Sadly, I have spent literally 20 years now reading computer model data about weather and storms here. The further you get away from any one person's area of local knowledge, the less accurate a forecast will be.  (AKA, people who ask me 2 hours away I can take a stab at it but it won't be great, I have not invested as much into understanding your area.

With that, I accept part of the map will be wrong somewhere.

My totals are going up. Honestly, there is some wiggle room especially in the Lynchburg area for a tad more than I show even though my totals have increased.   I am actually typing this up before the noon model data believing if anything we see another drift north on the snow totals.


I'll save you the weather jargon. This is a big wet system. There is just cold enough air in place and it will snow. A lot. Any place may end as sleet or freezing drizzle. Places in Charlotte, Pittsylvania and Henry County may mix a little more but will still get crushed.  There may be a few minutes where it snows so hard you just stop and smile and say WOW! I expect a few Facebook posts of " Heaviest snow ever". I would not be shocked to see 2 inch an hour snows at some point tomorrow in all areas.

I'll start tweeting/posting more on FB as we get close with the latest up to date information and will include computer modeled snow maps at this point forward.

Noon data looks even better, FYI 

Tuesday, December 4, 2018

Weekend storm potential update!

Short Summary: Models continue to show the potential for a signficant snow event Saturday into Monday.

Can you tell me how much?? It is still too soon to throw out amounts. Most model data is showing  1 to 2 inches of liquid falling out of the sky for the event, and most of that is snow. There is a risk of some mix, all regions but especially southside regions.
(Snow is usually 10 to 1 ratio, so 1 inch of precipitation is 10 inches of snow.

Can this really happen, it's awfully early in the cold season? That's a great point and it would be quiet the anomaly for event over 6 inches this early in the season. For recent history, I moved to Lynchburg in 1996 and we had 1 storm 6 inches or more this early in the year, back in 2002 (And actually an analog year this winter too)

What can go wrong and we won't get any  or much snow? 
There is quiet a bit that can go wrong.

1. Storm remains too far south and we get fringed.
2. Storm comes too far north and we flip to ice and rain.

Both are possible. The models currently oscillate between a great track for our region and a tad suppressed, especially the regions north of HWY 460.

What can go right? 
I don't post snow maps 5 -6 days out. It's poor taste and people struggle with uncertainty. Simply beause the models change doesn't mean the event isn't or is happenning.

With that, some of the crazy runs had a large swath of 20+ inches across our region. This was accomplished by the primary batch of snow targeting our region and then the upper air support taking a great track that keeps it snowing another 12 hours that racked up the 20+ inches. Not a likely outcome, but could be partially right where we get the majority of our snow Sunday then a second batch falls into Monday Morning.

When will you give us accumulation ideas? 

If the model data is consistent, I will blog up tomorrow "floors and ceilings"..

Meaning, if everything goes wrong we can expect XYZ if Everything goes right we can expect XYZ.

Saturday, December 1, 2018

Next weekend's possible Snow/Ice event..

There has been chatter about this event for several days now so I figured I'd write up rather than short tweets and posts that lack detail. 


Timeframe:

Dec 8 to 10th--

Set up:

Cold air filters in as an impulse rides along the sub tropical jet. This means timing is everything. Some runs are slower with the storm and the cold air is LEAVING meaning a chance to ice/rain while others are too fast with the storm and the cold air isn't here yet, meaning rain to ice to snow.  Models that show the storm starting overnight Friday are warmer to start while others that Delay the onset to Later Sunday end as Rain.

Could this be a significant event:

Yes, but a lot can and will change in 6+ days. Cold air is often not as cold as modeled and storms like to start a little quicker. (read above, this could mean more ice/rain, less snow)

What will I see on Social Media:

Expect a strong influx of snow maps from every backyard forecaster. Take them with a grain of salt. They often include what would fall as ice/sleet and even rain as snow.  They are useless at this time, and quite honestly most of the time.

Any initial guesses on accumulations:

Anyone who says they have a strong idea on what will happen at this point is foolish. Don't trust them.  Many of you may know I am Family Counselor in real life and in both meteorology and counseling, you have to be comfortable with gray areas and uncertainty. This is the case here.

1. It's early in the seasonan and we don't know the seasonal biases on the models yet.
2. We will have to deal with always present adjustment north modesl do  as we get closer.
3. It's a long ways out so the data will have several changes and adjustments.

With that,

Places along and West of the Blue Ridge  and north of Hwy 460 have the best chance of a plowable snow, with some ice mixed in, places south of that region may still see snow but now as much and an increased risk of ice/rain. 

I will start tweeting and posting maps and thoughts will more comprehensive blogs when I need to convey more information.

Thanks for sharing with your friends and family.

Wednesday, November 14, 2018

Early season Warnings, Watches and Advisories.

Pretty straigh forward forecast on tap.

Today will be cloudy and chilly with a chance of some drizzle. Temps will be steady or slowly drop.  For most of the region, temps will be mid to upper 30's by late evening. Rain and sleet move in from the south after midnight. Temps fall to and then below freezing. Rain will quicly mix with and then change to sleet, and then freezing rain will mix in. By mid morning most areas should be all freezing rain, with rain southside and then end as rain.  The western regions will have some snow showers over night Thursday.

I expect most schools to be closed tomorrow.  Road won't be horrible but they pretty much close for everything. Some places like Lexington and Covington may see 3-4 inches of sleet while Roanoke, Blacksburg and Lynchburg will see closer to an inch. Southside will have a trace and some ice but not a big deal.

I've attached a map from the NWS to show current watches and advisories and my call on ice/sleet.
I expect all the Blue areas to be upgrade to warnings, basically everyone along and west of the Blue Ridge

Decent sleet accumulations north and west of Roanoke and Lynchburg. They may never get above freezing some of those regions. Anything south and east of the blue line will see some sleet and freezing rain but only trace amounts. 


FWIW, pattern looks pretty amped the week after Thanksgiving. Thanks for sharing my blog with your friends and family :)


Sunday, November 4, 2018

Final Winter Outlook for Lynchburg, Roanoke, Blacksburg and Danville Areas 2018-2019

I did way too early outlook here and stated that we could see a rather cold and snowy winter. Because some other factors could change, I left it open ended where changes could be made to my initial thoughts.


So, did things change? 

Short answer is no. We still have a west based modiki El Nino that will likely be weak to moderate.  The  PDO looks to be positive and the majority of climate models show good jet stream configuration that lends to cold and stormy in our regions. 

What do the official mets say? 

The NOAA official outlook is normal temps. Many to most private sector mets are on board with a colder than normal and snowier than normal winter. (Look up Wxrisk, RaleighWx if you want two public access winter forecasts)

What is Normal for our region

Tempature data is accessable on the NWS Blacksburg but snowfall per region on a long term average:

Danville 10 inches. 
Lynchburg 17 inches
Roanoke 19 inches
Blackburg 22 inches. 

I am using long term because there were some data errors in the early 2000 and we also had some less snow winters in the 00-08 winters. 

Tempatures:

In general will be 2-4 degrees below normal for the winter. 

Snowfall
 125 to 200% of normal snowall. 

Danville 14-22 inches for the winter .
Lynchburg 20-30 inches for the winter. 
Roanoke 22-32 inches for the winter. 
Blacksburg 26-40 inches for the winter. 

These as based on regions-- you should have an idea if your place does better or worse. EG: higher elevations in Roanoke like Bent Mountain do better than the Valley Floor on Orange ave. 

Confidence Level: 
The last super big winter, 09-10 I was fully convinced we were on the way to a banner winter. There are a few subtle differences that knock my confidence down a couple pegs but still lend credence to a big winter being on tap. 

25% chance we come in under my snow totals. 
50% chance we end up in that range. 
25% we out perform what I predict happens. Right now, these numbers put us just outside a 10 winter for our region. If this pattern develops as maximizes potential, we could end up with a top 5 winter ever. 

Winter Development

We will actually have a pretty cold pattern starting next week and will last about 2 weeks.  There is a decent show we may see our first flakes of the winter. 

December may favor a chance or window for a snowstorm, like late month between the 20th and New Years Day. 

I favor the pattern setting up for our "heart of winter" by late January. Late January through mid February should be highest risk for cold and snow. 

March could go either way but the pattern on many models still look solid for chances for snow. 

3 comparable winters:

09-10- Big December snow storm, 2 minor events. 
January- Big storm late month then active first 2 weeks Febuary. Lynchburg had storms of 12.5, 11.2 and 8 inches. 
02-03
No BIG snow storms but numerous events of 3-6 inches from early December Forward with a near miss where 4 inches of sleet would have been 14 inches of snow in Mid February. 
86-87
New Years Day snowfall of 3-5 inches, Back to back big snowfalls on Jan 22 and 26 of 10-15 inches and then another 2 events in February 

There are other years that have similiar but not as simialir patterns that had less cold and snow. (06-07, 87-88)

Share this outlook with our friends and make sure to follow Virginiawx on facebook and twitter for important updates. 

Saturday, August 18, 2018

Winter "Pre" Previews are trickling out.. If you like cold and snow you will LOVE..

Winter outlooks done by mets/ weather hobbyists are more fun than accurate at times but they do make fodder to read and post. I've noted a few notable mets with early previews and others tossing hints.

I have some early thoughts for the areas including Lynchburg, Roanoke,Danville and Blacksburg.

Most guess are predicated upon:

1. We will most likely have a low to moderate Modoki El Nino. This means the Pacific, especially in the mid pacific known as Regions 3/4 will be in an El Nino phase. 

2. The PDO should be positive- Warmer water closer to the north pacific coast from Alaska down towards the US will be warmer. 

3. The Atlantic MAY be more favorable for high lattitude blocking in the NAO and AO regions.

If you have every kept up with my blogs, those are all really good things if you like cold and snow. We always blog from the perspective that snow is a good thing,.

A modoki El nino is the closest winter  to a consistent theme.  Most end up remebered for being fairly cold and rather snowy.  Winters with similiar patterns were 86/87, 02/03 09/10 with other years having lesser levels of commonalities. 

86/87 is remember for have back to back 10-14 inch snowstorms in our area from Jan 22 to 26. Region had 30 to 60 inches of snowfall.

02-03 had MANY storms in the 3 to 6 range and a BIG storm ended up being sleet here (in the 3-6 inch range of sleet). The region had 20-50 inches of snowfall for the winter. 

09/10 had 2 storms over a foot and another get really close. Snowmaggedon dumped close to 15 to 30 inches region wide over a few days but DC north had 40 or more inches in a 10 day stretch.  Seasonal totals were 25 to 50 inches region wide. 

With that,  nothing is every a lock-- especially before we have an offical El Nino and a few other variables. 

If we get to October 15, we know the Modoki El Nino is happening and the other factors are in place, my winter outlook would be:

Temps regions wide-- Seasonal 1-3 below normal for the winter. 

Snowfall, by city. 

Danville region/southside- 10 to 20, but a lot wiggle room for more. 
Lynchburg Area 18 to 28 inches, with higher end potential. 
Roanoke Valley region- 21-31 inches, potential for more. 
Blacksburg, NRV and Highlands Region- 25-35, even more in Lake Effect areas. Also, potential for much higher totals. 

Each city's top 10 snowfall winters has 2-3 modoki winters in those totals. 

Modoki El Nino's are known for having 2 or more LARGE events of over 10 inches.. once snow gets into double digits around here, it's a memorable event. 

There is also a "hot" period from around January 20th until February 10th or so that has a historical precedent these large events with other events being more scattered thoughout the winter season. 

That time period is often easily identifed  in advance by-- Modeling showing strong blocking in the Artic/Greenland region (Negative A0/NAO cuplet) positive PNA(Ridge on the west coast) and the SOI (Southern oscillation index) dropping  7-10 days in advance. (This is tied into the sub tropical jet becoming active)If that happens we could pop 2-3 winter events in a 7-10 day period. 

A couple runs of the seasonal runs from the Canadian Model and European model showed literally perfect 500 mb maps if you wanted a cold and snow winter for December to March. These maps displayed blocking on the west coast and artic/NAO regions with clear evidence of a strong sub tropical jet. Sub tropical jet is very important for our region because we do sit far enough south that we need a pretty unusual pattern to have the northern jet suppressed for snow in our region. 

With that, we are only on August 18th and a lot can and will change.  It is completely possible that we have all the pieces I cited in perfect alignment and we end up with a rather tame winter. This outlook previews where I am likely heading, but will updated my thoughts hopefully by late October.