Most of my friends and followers for my weather stuff likely follow other weather resources ( Yes, I consider that cheating :)) Haha, I should make a list of good people to follow (Kevin Myatt, Blue Ridge Weather, Wxrisk) and those to avoid (DooleyCaster)
So, this means that most knew the pattern change to cold was coming. However, what it means in your backyard is much different. Here are a few thoughts.
1. It will be cold by December 7th. Well below normal for a few days here and there and seasonable cold many other days. Normal to above will be limited, but still happen.
2. The pattern looks more cold than not through December 20th, then make sink back colder after a lull or small break. Most data supports cold through the end of December and maybe even into the first 2 weeks of January. (The further out we get, the more risk is involved with that statement)
3. Most people care mostly about snow chances. Now, I do love a cold brisk day.. but reality is cold without snow kinda sucks. So, what do we know about snow changes.
A. No specific threats to really track. The models have flashed a couple of things starting December 7th, but nothing at all to "track".
B. It's not out of the relm that we don't see a decent snow, even though it will be cold.
C. With that, It's been snowless in December since 2010, and I think odds are greater than 50% that we break that streak.
Types of storms that impact our area (Central and Southwest VA, including Lynchburg, Danville, Roanoke and Blacksburg) that bring ice/snow to the region.
1. Nor Easter, Coastal lows(Also called Miller A )- These are the classic big storms. They originate in the Gulf and head up the coast. These have the most potential for big events.
Risk of mix- high, especially east of the blue ridge.
These storms often deepen quickly, which creates for stronger winds.
2. West of the Mountains (Miller B)
These storms form in the south/west and end up west of the mountains. At some point, the jump to the coast, 99%of the time too far north to impact our area.
These often start as snow, change to ice and eventually rain. Snow amounts can be small to at times significant (each set up is different, and is dependent on the strength and depth of the cold air in place
3. Clipper systems (Alberta, not Los Angelos)
These systems originate over the Alberta Region of Canada and head south east. Most often, the pass to our north, but in times of strong blocking, will dip over our region. These systems are usually in the 1-3/2-4 inch amounts with the occasional amounts hitting the 3-6 inch range.
4. Overrunning-
No realy defined low pressure, but cold air in place and the flow aloft turns to the south and southwest pushing warm air our direction). These systems vary from ice events to decent snow events. Bigger overunning events can be in the 6-12 inch area, but more often are a few inches that changes to ice ( Think this way, if there is cold air in place and warm air pushes in, it would eventually change to ice/rain unless more cold pushes in
5. Souther slider- A coastal low like a nor easter that heads out to sea near the NC coast rather than up the coas.t
Less likely to mix, can be a big or biggest event
Now, these are labels we put on storms and not every storm falls into a box like I've described. Once we have a few storms to track, this is a handy glossery to use when I start talking about storm tracks.
Wednesday, November 29, 2017
Sunday, November 19, 2017
A winter outlook so to speak..
In the past I have done a more in depth write up and conveyed more "personal"ideas about what may happen in the upcoming winter. In General, long range at some levels is more of a "good guess" area rather than skill. Often I read many outlooks then do some local research and put out a forecast. This year, I have some ideas
This year we have two schools of thought.
1. Normal "La nina" winters which would favor milder tems and less snow/dry.
2. Other impacted "La Nina "winters which would feature more snow/maybe more snow.
- Other impacts are the QBO, Hurricane season and global SST's.
Analog years are harder in the context of weather or not you are a "believer" in some type of climate change, the globe is very warm and this does impact our sensible weather. You could go above normal temps in an season at this point and be correct maybe 80% of the time.
For our area (Lynchburg, Roanoke, Danville, Blacksburg) I'm to hedge colder, with below normal snow, but due to ice/mix and dryness.
Temps- All Areas Normal to -1. I do think we see a couple of significant artic outbreaks. Let's be honest, if our lows are in the single digits with wind chills, kids are getting snow/Cold days from school.
Snowfall-
Danville 2-12 inches
Lynchburg 5 to 15 inches
Roanoke 7 to 17 inches
Blacksburg 11-21 inches.
Upslope regions will be above normal (those places that just snow when it's cold)
Why the weird snowfall range?
La Nina winters tend to lack the sub tropical Jet. With that you tend to have system that are a smidge to north for our region. Storm track may feature systems going into eastern Kentucky then jump to the coast north of our region. Those are classic snow to mix or just mix events here. The risk for increase blocking could push those to our south under the block and increase our snowfall.
Snowfall is a guess at best, so take that for a grain of salt. I'd expect a little drier than normal winter. IF we over achieve on blocking (Blocking up north pushes cold air south) during an active storm pattern, we could easily over achieve on snowfall.
Be ready for frequent twitter, facebook and blog updates when pattern changes arive. We should remain seasonable chilly for the rest of the month. Good bet that we remain snow/ice free through mid December.
Thursday, September 7, 2017
The impact of Irma on Roanoke, Lynchburg , Danville and Blacksburg
So, the blog has been dusted off for Irma. I'm a shameless winter guy but this is a big deal event in some areas and worth sharing ideas about. If you are reading this blog, again this is a discussion for Lynchburg, Danville, Roanoke and Blacksburg region.
Key phrase for our region:
Know the difference between disruptive and catastrophic.
Harvey was catastrophic in 2 ways.
1. The landfall region was horrible. Stormchaser iCyclone was in that region noted Click here for Harvey Landfall
2. The flooding was caused by the lack of movement and 30-50 inches of rainfall over a large region including Houston Metro.
Irma has been and will be catastrophic in a large area. Most have already viewed the footage from St. Martin and Barbados which are humanly horrific and hard to watch.
The track that is possible of destroying the more islands, avoiding Hispaniolia and Cuba as it gets a little stronger over the warmer water, landfall near Miami, then head due north just off shore (note the slight curve of the coast that could allow a due north track to get just off shore). This allows the eyewall scrape almost the distance of the eastern Florida coastline, a short timeover water before a final landfall in South Carolina region. Adding, a large storm like this has an expansive wind field and a larger storm surge. Most of that region will experience a catastrophic event.
Meanwhile, we don't really know what the impact will here because the track has yet to be determined this far north.
Worse Case scenario: Irma Tracks from Landfall in SC to a Point near Martinsville/Galax area. most of the region sees 2-6 inches of rain and wind gust could reach 70mph, especially nearest the storm and the highest elevations.
In that case, we see some flooding, a good amount of power outages and life is disruptive a few days to maybe a week. It may be a challenge to get a hot meal, some power outages, local flooding in flood proned areas, but nothing remotely close to what we have noted in the islands so far or what will happen over the those who get the direct impact of a Cat 4 or 5 system. In our region, Tropical Storm conditions are a worst case scenario.
Current trends have been a secondary landfall in South Carolina and a westward movement that keeps the worst away from us. We'd see winds up to maybe 30mph and under 2 inches of rain.
We could also have a mid track that meets those conditions in the middle, with up to 4 inches of rain and wind gusts up to 50 mph.
Point being, it's always smart to check flash lights , candles and batteries. It is always smart to have some non-perishables and keep some water bottles handy in our region of Western Virginia. Even if this event isn't a big deal, you are protected agains a future ice storm, derecho and even zombie outbreak. However, there is little or no chance of a catastrophic event here. In a worst case scenario, we have up to a week of smaller disruptions in smaller areas.
Supporting my point that we wont have a catastrophic event here..here are the local observations from Fran in 1996. Our highest winds were gusts to 36 and 6 inches of rain total. Rain and winds at 30mph is a lot more intense then one would recall and I lived in a second story apartment with cheap windows and the wind pushed the rain over the top of the window and leaked in that way. But, by 2 pm the sun was out and I went to the J Crew sidewalk sale in Forest.
Key phrase for our region:
Know the difference between disruptive and catastrophic.
Harvey was catastrophic in 2 ways.
1. The landfall region was horrible. Stormchaser iCyclone was in that region noted Click here for Harvey Landfall
2. The flooding was caused by the lack of movement and 30-50 inches of rainfall over a large region including Houston Metro.
Irma has been and will be catastrophic in a large area. Most have already viewed the footage from St. Martin and Barbados which are humanly horrific and hard to watch.
The track that is possible of destroying the more islands, avoiding Hispaniolia and Cuba as it gets a little stronger over the warmer water, landfall near Miami, then head due north just off shore (note the slight curve of the coast that could allow a due north track to get just off shore). This allows the eyewall scrape almost the distance of the eastern Florida coastline, a short timeover water before a final landfall in South Carolina region. Adding, a large storm like this has an expansive wind field and a larger storm surge. Most of that region will experience a catastrophic event.
Meanwhile, we don't really know what the impact will here because the track has yet to be determined this far north.
Worse Case scenario: Irma Tracks from Landfall in SC to a Point near Martinsville/Galax area. most of the region sees 2-6 inches of rain and wind gust could reach 70mph, especially nearest the storm and the highest elevations.
In that case, we see some flooding, a good amount of power outages and life is disruptive a few days to maybe a week. It may be a challenge to get a hot meal, some power outages, local flooding in flood proned areas, but nothing remotely close to what we have noted in the islands so far or what will happen over the those who get the direct impact of a Cat 4 or 5 system. In our region, Tropical Storm conditions are a worst case scenario.
Current trends have been a secondary landfall in South Carolina and a westward movement that keeps the worst away from us. We'd see winds up to maybe 30mph and under 2 inches of rain.
We could also have a mid track that meets those conditions in the middle, with up to 4 inches of rain and wind gusts up to 50 mph.
Point being, it's always smart to check flash lights , candles and batteries. It is always smart to have some non-perishables and keep some water bottles handy in our region of Western Virginia. Even if this event isn't a big deal, you are protected agains a future ice storm, derecho and even zombie outbreak. However, there is little or no chance of a catastrophic event here. In a worst case scenario, we have up to a week of smaller disruptions in smaller areas.
Supporting my point that we wont have a catastrophic event here..here are the local observations from Fran in 1996. Our highest winds were gusts to 36 and 6 inches of rain total. Rain and winds at 30mph is a lot more intense then one would recall and I lived in a second story apartment with cheap windows and the wind pushed the rain over the top of the window and leaked in that way. But, by 2 pm the sun was out and I went to the J Crew sidewalk sale in Forest.
Summary: Those in the Bahamas, Turks and Caicos, Florida will have a horrific and life changing event. Failure to head warning will have significant consaquences including loss of life.
In our region, in a worse case scenario we have a disruptive event. At this point, we don't have enough information for a "exact" forecast at this point.
I'll throw another update or two out there in the next few days.
Sunday, March 12, 2017
How Much Snow Monday night and Tuesday??
I'll start with the details and then elaborate for those who care!
New River Valley up 81 to past Roanoke 3 to 6, up to the Blue Ridge.
East of the Blue Ridge - North of Altavista , Cutting north to Farmville , Including Lynchburg 2-4.
Martnsville, Danville, Ect coating to 2 inches.
If this is a Dud: Ending as snow in NRV, LYH and ROA and all Rain southside.
If we over achieve, 4 to 8 NRV, ROA and LYH, 2 to 4 down to Martinsville and Danville.
Discussion:
If this were January, we'd be looking at 6-10 inches region wide, maybe some bonus snows in the north and east areas. It's not too warm, it's just March, mid March at that.
To not overcomplicate my discussion, we have storms that are phased and unphased, Phase, simply put is when 2 branches of the jet streams, and their upper air energy work together.
Early on, a phase seemed likely, then models moved away from that. Today, they are more phased and the net gain is best snows should be west of the Blue Ridge.
What a phase does is strenghten the low fast enough to cool the air from top to bottom by creating strong vertical motion upwards. The models currently strengthen the low a little sooner and enough cold is in place along -81 for mostly snow, or rain changing to snow. As the low deepens and pulls east a rapid change over takes place. However, the snow ends pretty quickly after it changes over with maybe 2-3 hours of accumulating snow and then 2-3 hours of light snow and flurries.
Details:
Roaonoke and NRV, a mix of snow, sleet and rain develops late afternoon, changing to all snow in the evening. Snow will be briefly heavy. Snow ends in the pre dawn hours. 3 to 6 on colder surfaces, slushy mess on roads, etc.
Area including Lynchburg: Rain and sleet develop, maybe all rain for a while then changing to snow. Snow could be heavy an hour or three, before ending as 2-3 hours of light snow and flurries. It's gone by sunrise with 2-4 inches falling, mainly grassy areas. The roads will have some slush on them..
Southside. Rain and maybe a little sleet ending as snow, coating to 2 inches.
Crazy talk: In my "weather chats" with various people I've predicted that if the low deepens to 995mb before Cape Hatteras we see 4-8 in all areas except southside. I still believe that. I think we miss it by 50-75 miles. (AKA, Past the VA/NC border.
More Crazy talk: Pretty good odds school is out Tuesday. Snow will be gone by noon. Gone, as in melted.
Even More Crazy Talk: Winter is hanging on a little after NO winter. May need to blog later about other events.
What can go wrong? If the low is SLOWER deepining, we get some rain ending as lighter snow, but no accumulations to speak of.
If you're up, the snow may rock a couple hours nice big flakes from 10pm to 3am.
Thunder, as the low deepens with both the rain and snow is possible.
Huge event just north of DC. My baby sis lives 20 miles NW of Philly near where I was raised, I think she sees 12-20 inches.
I think that the NWS will go Winter Weather advisory for most areas NOT southside and MAYBE winter storm watches/warnings for Amherst, Bortetourt and Rockbridge Counties.
Doubt I will make another full blog. Thank you for the "ad clicks"of appreciation.
I will update with model runs, and updates, upgrades and downgrades on social media. Remember you can follow my FB Page, VirginiaWx me personally, Keith D. Huffman, (do a FR or follow) and/or twitter which is VirginiaWx
New River Valley up 81 to past Roanoke 3 to 6, up to the Blue Ridge.
East of the Blue Ridge - North of Altavista , Cutting north to Farmville , Including Lynchburg 2-4.
Martnsville, Danville, Ect coating to 2 inches.
If this is a Dud: Ending as snow in NRV, LYH and ROA and all Rain southside.
If we over achieve, 4 to 8 NRV, ROA and LYH, 2 to 4 down to Martinsville and Danville.
Discussion:
If this were January, we'd be looking at 6-10 inches region wide, maybe some bonus snows in the north and east areas. It's not too warm, it's just March, mid March at that.
To not overcomplicate my discussion, we have storms that are phased and unphased, Phase, simply put is when 2 branches of the jet streams, and their upper air energy work together.
Early on, a phase seemed likely, then models moved away from that. Today, they are more phased and the net gain is best snows should be west of the Blue Ridge.
What a phase does is strenghten the low fast enough to cool the air from top to bottom by creating strong vertical motion upwards. The models currently strengthen the low a little sooner and enough cold is in place along -81 for mostly snow, or rain changing to snow. As the low deepens and pulls east a rapid change over takes place. However, the snow ends pretty quickly after it changes over with maybe 2-3 hours of accumulating snow and then 2-3 hours of light snow and flurries.
Details:
Roaonoke and NRV, a mix of snow, sleet and rain develops late afternoon, changing to all snow in the evening. Snow will be briefly heavy. Snow ends in the pre dawn hours. 3 to 6 on colder surfaces, slushy mess on roads, etc.
Area including Lynchburg: Rain and sleet develop, maybe all rain for a while then changing to snow. Snow could be heavy an hour or three, before ending as 2-3 hours of light snow and flurries. It's gone by sunrise with 2-4 inches falling, mainly grassy areas. The roads will have some slush on them..
Southside. Rain and maybe a little sleet ending as snow, coating to 2 inches.
Crazy talk: In my "weather chats" with various people I've predicted that if the low deepens to 995mb before Cape Hatteras we see 4-8 in all areas except southside. I still believe that. I think we miss it by 50-75 miles. (AKA, Past the VA/NC border.
More Crazy talk: Pretty good odds school is out Tuesday. Snow will be gone by noon. Gone, as in melted.
Even More Crazy Talk: Winter is hanging on a little after NO winter. May need to blog later about other events.
What can go wrong? If the low is SLOWER deepining, we get some rain ending as lighter snow, but no accumulations to speak of.
If you're up, the snow may rock a couple hours nice big flakes from 10pm to 3am.
Thunder, as the low deepens with both the rain and snow is possible.
Huge event just north of DC. My baby sis lives 20 miles NW of Philly near where I was raised, I think she sees 12-20 inches.
I think that the NWS will go Winter Weather advisory for most areas NOT southside and MAYBE winter storm watches/warnings for Amherst, Bortetourt and Rockbridge Counties.
Doubt I will make another full blog. Thank you for the "ad clicks"of appreciation.
I will update with model runs, and updates, upgrades and downgrades on social media. Remember you can follow my FB Page, VirginiaWx me personally, Keith D. Huffman, (do a FR or follow) and/or twitter which is VirginiaWx
Friday, March 10, 2017
Sunday looking small- Monday- Tuesday Standing Tall
First, Sunday-- Southside and Mt Empire/NRV may get more than a coating but not big deal . Roanoke-Lynchburg, flurries and some light snow, not much more than a coating. Not a big deal. The energy got sheared out and suppressed. I don't think many churches will be looking at closing except the extreme southwest areas near Hillsville.
Monday into Tuesday looks like a legit good threat. 5 days out, some changes will happen, but It seems things are slowly coming into focus.
A low pressure, aided by the "lack of storm"Sunday will form in the Gulf of Mexico and move from a point east of Charleston, SC to just east of the VAB. A clipper type system with some northern energy is moving towards us at the same time. The models have moved away from a strong phased system, but there is some interaction which helps the storm get stronger.
You all know that I like snow,so this is pro snow-- if you want snow
1. We want the low stronger, faster.
2, We want it close enough to bring the best moisture, but far enough to not change over.
3. To maximize accumulation, a little slower on the onset to avoid the March sun.
General Pitfalls:
1. It won't be all snow in southside, It should start as snow, mix with sleet/rain and then end as snow.
2.The sleet line may challenge forecasts all the way up to the Blue Ridge Parkway, including Lynchburg.
3. Western regions COULD see a little less precipitation hence a little less snow.
General ideas: WAYYYY to early to set out calls at this time, but I want to give a heads up to the impact possible. This is clearly subject to change.
Martinsville to Gretna to Brookneal and south will mix and a broad 1-4 inches of snow and slush seem possible.
Every where else, including Blacksburg, Roanoke, Bedford, Lynchburg 4 to 8 inches of snow seem like a good starting point. We have plenty of time to fine tune and adjust these based on the exact tract and strength of the low pressure.
I'd like to see at least 4 in LYH and 6 in ROA to continue the double digit snow years to 5 years.
Click an add for appreciation. Remember, I will tweet/post about the model runs during the day.
Monday into Tuesday looks like a legit good threat. 5 days out, some changes will happen, but It seems things are slowly coming into focus.
A low pressure, aided by the "lack of storm"Sunday will form in the Gulf of Mexico and move from a point east of Charleston, SC to just east of the VAB. A clipper type system with some northern energy is moving towards us at the same time. The models have moved away from a strong phased system, but there is some interaction which helps the storm get stronger.
You all know that I like snow,so this is pro snow-- if you want snow
1. We want the low stronger, faster.
2, We want it close enough to bring the best moisture, but far enough to not change over.
3. To maximize accumulation, a little slower on the onset to avoid the March sun.
General Pitfalls:
1. It won't be all snow in southside, It should start as snow, mix with sleet/rain and then end as snow.
2.The sleet line may challenge forecasts all the way up to the Blue Ridge Parkway, including Lynchburg.
3. Western regions COULD see a little less precipitation hence a little less snow.
General ideas: WAYYYY to early to set out calls at this time, but I want to give a heads up to the impact possible. This is clearly subject to change.
Martinsville to Gretna to Brookneal and south will mix and a broad 1-4 inches of snow and slush seem possible.
Every where else, including Blacksburg, Roanoke, Bedford, Lynchburg 4 to 8 inches of snow seem like a good starting point. We have plenty of time to fine tune and adjust these based on the exact tract and strength of the low pressure.
I'd like to see at least 4 in LYH and 6 in ROA to continue the double digit snow years to 5 years.
Click an add for appreciation. Remember, I will tweet/post about the model runs during the day.
Wednesday, March 8, 2017
Snow still on the table, maybe even a second storm.
Quick update this AM:
1. Event 1, Saturday night into Sunday is still on the table. The storm trended south, as expected and is also weaker (For those wondering, it had 10-14 inches region wide a couple runs of the American model) The Euro model is weakest and most south.
A. Can't totally rule out the weakest, most southern track.
B. The big, 10-15 inch event was never really an option.
C. Light to moderate snows still on the table. Light to moderate, 1-3, 2-4, 3-6 type events. This is not a lock yet.
2. Trends are for a second event "maybe" Tuesday. This could form just a smidge north and miss our region or be just a small event a blow up just to our northeast.
A. The Canandian Model is very agressive with this storm, give a NICE storm (but little Sunday)
B. Euro forms it but WAY north for us.
C.GFS is coming around to a small event Sunday and small/moderate event Tuesday.
D. Temps could be an issues with this, especially east of the Blue Ridge.
My thoughts: Even with the weaker solution, I think we see a slow shift north in this event Sunday. This won't be a "huge" but a decent event is possible, and a smaller event is likely.
Tuesday: 6 days out-- A lot can change, not too confident for our area yet. I like the areas north of Philly for event 2.
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Will continue updates on model runs at noon today.
1. Event 1, Saturday night into Sunday is still on the table. The storm trended south, as expected and is also weaker (For those wondering, it had 10-14 inches region wide a couple runs of the American model) The Euro model is weakest and most south.
A. Can't totally rule out the weakest, most southern track.
B. The big, 10-15 inch event was never really an option.
C. Light to moderate snows still on the table. Light to moderate, 1-3, 2-4, 3-6 type events. This is not a lock yet.
2. Trends are for a second event "maybe" Tuesday. This could form just a smidge north and miss our region or be just a small event a blow up just to our northeast.
A. The Canandian Model is very agressive with this storm, give a NICE storm (but little Sunday)
B. Euro forms it but WAY north for us.
C.GFS is coming around to a small event Sunday and small/moderate event Tuesday.
D. Temps could be an issues with this, especially east of the Blue Ridge.
My thoughts: Even with the weaker solution, I think we see a slow shift north in this event Sunday. This won't be a "huge" but a decent event is possible, and a smaller event is likely.
Tuesday: 6 days out-- A lot can change, not too confident for our area yet. I like the areas north of Philly for event 2.
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Will continue updates on model runs at noon today.
Monday, March 6, 2017
Yes, the snow talk is legit..5 things you need to know about the weekend snow potential in Roanoke, Lynchburg, Danville and Blacksurg.
But, 5 days is a long ways away.
I try to communicate the uncertainty when I talk storms and explain what can go wrong, because things will go wrong. 5 days is forever and we are currently on the southern fringe of a storm. Usually, the north trend would seem huge and we'd already be telling you yeah, models says yes but the end results will be north of here.
There are occasions where storms trends south.. those usually have strong confluence and/or strong cold air advection. This one currently has both..
So- basically a storm slides to our north Friday and drags a cold front through. Cold air is still pushing in as the storm approaches form our west. The blocking/confluence forces the storm to our south (EG, near Nashville, to Charlotte then reforms off the NC coast) Yes, it's march, yes- we are having a very warm winter but our weather history is littered with storms that had very warm temps the day or three before the event.
So here are 5 key things to know!
1. 5 days out is a long time and things can and will change. Anyone who tells you "exactly" what will happen is just guessing.
2. There is reason to suspect there could be a further adjustment south which is great if you want snow because of confluence/north trends.
3. Beware of snow maps on FB, what your app says and anything old floating around. I've had someone tell me "it's supposed to be 50 saturday, my app just says rain, etc) Bloggers and really anyone with a computer can pull up the latest model data. There are legit trends that point towards a storm.
4. If there is an event, timing looks to be Saturday late into Sunday. Literally all types of precipitation are possible meaning snow, sleet, rain and freezing rain. All options are on the table-- from a mostly rain event to a mostly snow event. 2 runs of the GFS push the rain/snow line right up to 460 from Roanoke to Richmondand ring out a good bit of snow really fast.
5. Model data at this point comes in every 12 hours, except the American Model (GFS) which runs every 6 hours. Each run should help clarify what direction we are going in. And, Relax--it's a March storm. Even if we max out snow and get a nice event, roads are much easier to clear in March.
2 Cool maps/graphs...
1. This is a composite of matching patterns based on what the models show 5 days out. Our region averages out to a 6-8 inch snowfall.
So, those are the best matches at 300 mb for the upcoming event. A perfect score is a 1.. Some of the bigger events listed.
2/20/83-- 18 inches Roanoke, 15 Lynchburg.
2/15/03-- Big sleet storm. 3-7 inches region wide.
1987 1-25 18 inches Roanoke, 13 Lynchburg.
3/12/1993-- 30 NRV, 19 Roanoke, 15 Lynchburg.
1/20/2010--8-15 inches region wide.
So, point being we have some potential for some type of snowfall.
My thoughts match the analog map listed. I believe Winchester to Harrisonburg to Leesburg have the best shot for a 6+ inch event. Next area would be DC Metro down to CHO to Fredricksburg-- slightly less chance. The next bracket would include Roanoke, Lynchburg and Richmond. I think we see a shift south per the pattern but then the storm nudges north late, which always happens. Of course, all the midnight model runs could lose the event too :)
Will try to do a blog tomorrow evening and will tweet/post more during model runs. Feel free to share this and ask questions if you have them.
I try to communicate the uncertainty when I talk storms and explain what can go wrong, because things will go wrong. 5 days is forever and we are currently on the southern fringe of a storm. Usually, the north trend would seem huge and we'd already be telling you yeah, models says yes but the end results will be north of here.
There are occasions where storms trends south.. those usually have strong confluence and/or strong cold air advection. This one currently has both..
So- basically a storm slides to our north Friday and drags a cold front through. Cold air is still pushing in as the storm approaches form our west. The blocking/confluence forces the storm to our south (EG, near Nashville, to Charlotte then reforms off the NC coast) Yes, it's march, yes- we are having a very warm winter but our weather history is littered with storms that had very warm temps the day or three before the event.
So here are 5 key things to know!
1. 5 days out is a long time and things can and will change. Anyone who tells you "exactly" what will happen is just guessing.
2. There is reason to suspect there could be a further adjustment south which is great if you want snow because of confluence/north trends.
3. Beware of snow maps on FB, what your app says and anything old floating around. I've had someone tell me "it's supposed to be 50 saturday, my app just says rain, etc) Bloggers and really anyone with a computer can pull up the latest model data. There are legit trends that point towards a storm.
4. If there is an event, timing looks to be Saturday late into Sunday. Literally all types of precipitation are possible meaning snow, sleet, rain and freezing rain. All options are on the table-- from a mostly rain event to a mostly snow event. 2 runs of the GFS push the rain/snow line right up to 460 from Roanoke to Richmondand ring out a good bit of snow really fast.
5. Model data at this point comes in every 12 hours, except the American Model (GFS) which runs every 6 hours. Each run should help clarify what direction we are going in. And, Relax--it's a March storm. Even if we max out snow and get a nice event, roads are much easier to clear in March.
2 Cool maps/graphs...
1. This is a composite of matching patterns based on what the models show 5 days out. Our region averages out to a 6-8 inch snowfall.
2. A list of those analogs and explaining what events are popping up.
2/20/83-- 18 inches Roanoke, 15 Lynchburg.
2/15/03-- Big sleet storm. 3-7 inches region wide.
1987 1-25 18 inches Roanoke, 13 Lynchburg.
3/12/1993-- 30 NRV, 19 Roanoke, 15 Lynchburg.
1/20/2010--8-15 inches region wide.
So, point being we have some potential for some type of snowfall.
My thoughts match the analog map listed. I believe Winchester to Harrisonburg to Leesburg have the best shot for a 6+ inch event. Next area would be DC Metro down to CHO to Fredricksburg-- slightly less chance. The next bracket would include Roanoke, Lynchburg and Richmond. I think we see a shift south per the pattern but then the storm nudges north late, which always happens. Of course, all the midnight model runs could lose the event too :)
Will try to do a blog tomorrow evening and will tweet/post more during model runs. Feel free to share this and ask questions if you have them.
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