Monday, November 24, 2014

Fine line between heavy rain and heavy snow

Sometimes the tragedy is in that a perfect scenario presents itself and is not realized to minor, yet significant details. Had this storm been knocking on our door in EXACTLY one month, meaning Christmas eve, the area would be filled with glee that a post Christmas storm was on the way with what would be likely a 6-12 inch snowfall region wide. That would be simply awesome.

Remember weather is fluid and this has time to adjust...with that, I'm just not seeing the mechanism to cool the lowest 3000 feet of the atmosphere.


That blue line shows the freeze line- which this is at 10am, when the heaviest stuff is in our region.  3000 ft of 34-35 degrees just isn't accumulating snow.

Here is the text data in that range--




In this frame, the temp from 1800 feet down the ground is 34-35. could be snow falling, but not snow that will accumulate.

With that, the calender says November 24th and we have to deal with JUST warmer temps based where the calender is. With the models reading JUST too warm-- I mean, 3-4k feet down to the surface at 34-36 degrees during the height of the storm is just to warm to overcome.

Unless there are drastic changes--

Most places start as rain and end as snow. Most places see between .75 and an inch of liquid falling. Heaviest stuff clears our area by noon or so actually.

Places above 1500 feet see 2-4 inches, with up to 6 in highest elevations

Roanoke-- an inch or two of slush at best.

Lynchburg - Coating to an inch.

Danville- ends as snow/mix

It's going to rain hard for a while and at some point there is going to big fat flakes mixing in, but simply not enough cold air to accumulate.. at the lowest level of the atmosphere

I think Staunton north along 81 has a big event... I don't have time to break details for the rest of the world, but in our area I think we get a couple hours of scenic snow falling that coats the ground. Should feel festive.. North of 64, along 81 should have a nice 4-8 inch event.

Near miss, but still a miss.

My home internet SHOULD be fixed tomorrow...or Wednesday at the latest. If late evening model REALLY convinces me otherwise, I'll update. 

I get with the travel day this is a huge call for our region.. will blurb on FB and Tweet as needed.

Sunday, November 23, 2014

Thanksgiving Eve Snow..

I was 16 years old, my first year driving and we had a DECENT 6 inch snowfall Thanksgiving eve into the early hours of Thanksgiving. The first flakes started to fall as I walked to corner sub shop to grab the family cheesesteaks as we prepared the pies and other foodie stuff for Thanksgiving. I was living in Wilmington DE. Down in this area, daytime temps were just a bit warm and some rain ended as a little light snow and a coating to an inch fell.

If you refer to my blog from November 11th, I stated that the best shot of snow was going to be Thanksgiving week, and dangit if I wasn't right. On what is the busiest travel day of the year, if this thing reaches potential it's going to be a miserable travel day and I'd suggest anyone with family travelling from NC north to New England start to have alternative plans with leaving early or later than planned. This won't be a BLIZZARD but Wednesday may be a bad travel day with many cancelled flights, etc. I'm supposed to be driving to my mom's in Rehobeth DE, and think as of now we won't hit the road till Thursday AM.

The personal torture for me is that my home internet is acting up and I can't get the maps to load..I get a drip of net service that gives me SOME FB updates and chat. I'm currently at McDonalds eating pancakes and using their net service. (And I live in the ONE and only bad cell data spot in the city of Lynchburg so my ipad and cell are useless too)Cable service will be out tomorrow to fix it, but it is taking my competitive advantage away compared to other forecasting outlets. I'll be somewhere late afternoon where I can hop back on line and comb through the data.

I always write from the perspective that snow is a good thing, and despite the holiday we are NOT changing our format.

Basics- Storm moves in after midnight, towards morning-- 3-5 AM time frame and will be rain or rain and snow mix. At some point it flips to all snow and accumulates nicely. IF we can slow this thing down a few hours our snow totals go up. if it speeds up, the cold air doesn't have enough time to get in place and we get more rain.

Initial thoughts are we see 3-5 inches, with maybe 4-8 higher elevations especially west of BR above 1500 feet elevations. I think most places see .75 to an inch of liquid, but the start as rain with temps near 40 most areas and we bottom around at 32-33 most of the day. So, wet past snow all over everything. Get those christmas lights up early.

Can we get more?? Yes-- if the system slows down and the models are a tad warm as shown now. This is a rapidly developing storm and that's a very real possibility that we are at 40 degrees and an an hour we are at 33 with moderate snow falling. Think of March 16th this year-- we went from 48 and drizzle to snow in 2-3 hours.

Can we get less?? Yes-- the set up isn't ideal but the pieces work just well enough to give this threat. Any minor subtle changes would change the path and strength of the storm/cold will be huge.

You'll likely see some crazy snow maps on facebook and please don't feed the trolls, especially one out from the Euro. It's based on a 10-1 snow ratio and it simply won't be that good. Take those maps and multiply the total by .7 or so to get a legit number, and that is likely your upside. So, the EURO shows us getting about 10 inches, I'd take that as a 4-7 inch total for us. But, that's assuming we get an inch of liquid.

The Euro is leading the way,and it does usually on southern stream events (thanks almost el nino). The GFS has moved towards the EURO now, we are just waiting on the Canadian model and a newer version of the GFS (better resolution).With that, here is my first outlook. I'm way west of guidance because these southern stream events are ALWAYS way west. Feb 13th I was west of ANYONE else with guidance and I was still too east.

Here is a first stab at this-- COULD be way off and I'm running of some HUGE assumptions, mainly being this will be a strong system and the best bands will set up further west than modeled. That's a safe bet VERY often. If this was NOT a major travel day, we'd be in discussion mode, not making my lovely maps. :)


First Guess.. use with Caution. 

I'll throw out some tweets and FB updates before I get full access with info as passed along to me.

If we max out, I can see LYH getting 6-8 inches and maybe 10+ on higher elevations of the Blue Ridge. Not a forecast but just a Worst Case.. with some lingering leaves, some power outages could start to creep in.

Lastly, big shout out to Nick-- LU football star and blog reader and the entire team on the exciting win yesterday. I moved here 20 years ago to attend LU and what a thrilling season. What a way to get the first FCS playoff appearance in school history. Proud of the team!!

Tuesday, November 11, 2014

The Cold is coming, and has staying power.

As discussed last week, a pattern change is underway and cold front passes through later tomorrow and our high temps will be in the 40's, which will feel more like winter than fall. These cold temps should be more present than not until the first week of December (Being specific, usually colder than not but some days will be normal or even above normal)

Snow chances? A couple blips have shown up on radar.. even with super cold temps, we'd need everything to be perfect. There has been some FB/Twitter chatter about early next week and I'm not that excited on that event, especially outside of the mountains where it will snow this time of year with cold air pushing in. IF we get a legit shot to materialize, my hunch is that the week of Thanksgiving will be the best shot based on where the pattern will be. (AKA, nothing specific at this time)


Saturday, November 8, 2014

Watching the -AO, winter may start early.

I've been super busy with little time to really scrape the data like I should, but I've got enough sources and people I chat with that I'm on top and wanted to throw out some information.

First, you've likely heard a little chatter about some snow chances next week. Some of the model data has shown it off and on while other models are all over the place. Getting snow in November is about as rare as March 25th snows, but now we've done that 2 years in a row. Now, odds are it's like nothing, but some of the model data drives a cold front through and then a week wave follows behind. That would be our best set up for an event in November. Odds are, we end up with no snow.

Like poetry in motion, the snowcover gain has trigger some events and the arctic oscillation is about to tank and we could be having a sudden stratospheric warming (Which ties into the -AO and high latitude blocking) Big cold comes in next week and the -AO could reach close to -4 on the scale they use. One key piece is once it tanks to a -4 or -5 it usually replicates itself once or twice.  So, the bottom now looks to be about 3.5 or so, just a bit stronger and we could be in a colder pattern for 6 weeks or so.. which runs us up through years end.

Will keep you updated, but December may be looking colder than I had anticipated.
Strong -AO, usually breeds ANOTHER severely negative -AO

Saturday, November 1, 2014

Official 2014-15 Winter Outlook..

Quick summary, then we will get into some nuts and bolts with some "what if" scenarios..

Winter 2014-- 1-2 degrees below normal, with snowfall 15% to 50% above normal. 
Relative to normal, the coldest and snowiest period looks to be Mid January to Mid February. 

1-2 degrees isn't much I'd not be shocked if that 30 day stretch I mentioned is a -4 to 5. I think the we get a stretch where 2-3 storms beat us up pretty good in a 10 day period and snow falls on top of a snow pack during that stretch. 

Normal snowfall with my rage next
Blacksburg 23 - 30-35 inches this winter
Danville 12 inches  15-20 this winter
Lynchburg 17 inches 20-25 inches
Roanoke 19 inches 25-30 inches. 

December likely the mildest of the 3 winter months, but an event is always possible. Once the pattern breaks down from mid to late Feb to early March, it would be be simply over. 

Factors-

El Nino-- We are in a low end el nino, especially based on a scale called the MEI. This indicates somewhat of a more active sub tropical get, but not too much that would be too warm. 

PDO
Positive phase. It's interesting that long term negative phases are better for a cooler globe, but often a spike near the winter  to a positive in a short term aspect is good for our region. The  60's saw this common with a -PDO pattern, but a few good winters spiked towards positive. 

Eurasian snow cover
Off the charts- This has an incredible strong correlation to negative phase of Arctic oscillation, which is good for our region

QBO- winds way up in the sky. When bottomed out, and beginning to turn slowly towards negative has a connection to high latitude blocking. 

The one negative I see is sun spots are active now but its weighted towards colder and snowier. 


Can the winter end up with MORE snow--

Sure. Anything is possible. If we get a decent snow or two in December before the good pattern sets up that's a big tell. Also, if the Arctic Oscillation falls off the chart, it tends to replicate it self. So, if we see a -4 in December or early Jan, we will have enough time to cycle back to ANOTHER steep fall. 

Could we end up with less snow? Sure-- A met out of North Carolina named Allen Huffman released his outlook and out of the "analog" or matching years... the least snowiest was 1958-59 had 12 inches. So, the bottom may be somewhere around 10 inches and the snowiest years that had some match was upward of 40 inches in LYH. My range is where I think we fall based on current factors but clearly there are factors that can be hard to gauge.  

If I placed odds-- 60% my range is good, 10% chance we get higher, 30% chance we get lower than I forecasted. 

My greatest strength is spotting legit events and discussing them maybe a few days before you may hear about them from other media sources, so be vigilant in checking my blog. When it comes to snow, if I'm not talking about it I'm not to jazzed about it. When I'm fired up, you will know and I will update. Today's event unfolded about how I expected-- not a big deal around here, hence no updates. Some snow in Upstate NC on Nov 1 is a big deal in that area. Chilly weekend on tap with
a reminder that winter is just a stones throw away. 

Monday, October 27, 2014

Some winter thoughts and a remembrance for a meteorologist friend who passed away..

I'll do a more detailed winter outlooks, but outside the NOAA outlook which was rather interesting, I think 2 out of 3 or greater of the private forecasters (aka, the ones who give more detail and stick their neck out) will end up going cold and snowy compared to normal. One KEY tell has been the snow increase in Eurasia. (Which I've mentioned for years now)

With that, Long range forecasting is hard and I mean, last year I went warm and snowless and while snowfall was slightly above normal-- cold or cold coming was the theme last year. Enjoyable winter from a tracking stand point where I had one event after another. While the kid in me still enjoys playing in the snow, the fun is really in the chase now-- getting the storm right.

With that, my inclination is that temps this winter run 1-3 degrees below normal. I think the coldest 30 day period relative to normal will be Mid Jan to Mid Feb and snowfall will be normal to 25% above normal. Lynchburg averages 17 inches a year (Comment about that in a moment) So range of 17-23 inches? More "breaks" in the action where the Arctic Oscillation will be our driver for cold, that often breaks down for 1-2 weeks stretches even in negative phase dominated winters. IF we get a more robust sub tropical jet, snowfall could be more. Snowfall at some levels is just an educated guess because timing short waves is not something we know. It's a linear guess on the facts at hand. If we get one 15 inch snowfall, the other 8 inches would be really easy to come by.

More details later in the week, but that's the jist of where I am.

Touching on LYH snowfall-- I've seen FAR too many graphs showing Lynchburg 30 year mean at 13 inches. It's wrong. Way wrong- Huge data gaps where they just averaged in 0 for years they didn't keep records. The NWS had a consolidation in the mid 90's and observations didn't get done. Sean Sublette over at WSET does them now, but we had some huge gaps that were counted as zeros in the average. I've pointed this out to several mets and even reached out to the CLIMO center and was told I was wrong, and or my data didnt' count. Well, first-- Hello, this is science. It matters. It matters a lot. Second, isn't some data based on an education guessed combined with local obs (we've always had temps, winds and rainfall because it's automated. We just need someone to stick the ruler in the ground) And lastly, I'm just right. I can't do this now, but when I was about 25, I could name about every snowfall at my house as a child from ages 5 till I moved away from college. I can still piece together most winters and tell you if it was good or bad, and any "signature" snow events--etc. I do have a freakish memory, but I get this is a bit much.  I did keep records of the snowfalls here and have it documented. If you remove the missing years OR add my data you get a 30 year average of 16.9 to 17 inches.

RIP Rich Hitchens

Wanted to give a quick word about a meteorologist friend who passed away. He spent his career at the NWS and worked the DC area for a long while, ending as their Hydrologist. One of the cool things to me was on the documentaries on SuperStorm 93, they did a reenactment of DC office and I think he was in the footage as the met in charge of that office at the time. He was a great guy, good friend and helped the people who launched the weather board where I hang out connect with more meteorologists.

BUT, I was honestly star struck when I met Rich because as a kid all I had for weather information was local news, cable tv station that scrolled the forecast, a weather radio and the local NWS number that was a recording from the mets at the old ILG office (Wilmington, DE) Anyways, once Rich disclosed that he worked there in the mid to late 80's and I thought it was the coolest thing ever. Can't tell you how many times my Dad and I called that number for temperature updates, updated forecasts..etc. The short term forecast was 322-5151 and I've likely dialed that number thousands of time on an old rotary phone. They also had an extended forecast number which I believe was 322-7596 and it gave an extended outlook of 3-5 days and 2x a week it gave a 6-10 day outlook. If you called in business hours you could ask a met a question. My Dad and I use to call and fake like we were travelling to get more information (Like, knowing what happened down here in VA could impact our weather --etc) Rich told me he had no memories of "fake" calls but I always assumed it was transparent we were just idiots wanting to know if it was going to snow or not. Great memories with my Dad and likely Rich fielded a call or two. :)

So, just like as a kid I loved wrestling and would still think it's cool to meet my favorite wrestler -- Randy Macho Man Savage (Rip to that dude too), Meeting Rich was cool because of the connection to my childhood and I'm glad I got to know him because he was a good man. Tragic, Such a young guy at age 51..  322-5151 forever.

Sunday, October 12, 2014

Pushing towards winter...

Winter is approaching quickly and while we have some general ideas about how it will play out, October has some key data that needs to e considered before my winte outlook (Yes, the snow cover in Eurasia).

Update for Keith Allen who does a DC centered outlook, but I extrapolate what he does locally and he's had some good sucess in the past but he has some very off years too(Like we do)

This is a direct snip from a friend of his that knows his outlook. A DC radio station use to do a big deal when he released his outlook...

Temperatures:Above Average
Snowfall:Average
Rainfall:Above Average

Seasonal Temps:+1.3 to +1.7
Monthly: Dec:0 to +1
Jan:0
Feb:+4
Snowfall DCA:15"

Analog years:1974(5),1984(5), 1992(3)1997(8),2001(2)

Believes there will be a major ice storm around 1/15/15

Some friends in the met world think he does well the conditions are neutral- this year the El Nino is close to low end but the issues I see is that he has a STRONG El NINO, strongest on record and some La Nina too.

Other factors:

The El Nino has not gotten up to low end level yet, but it should peak between .5 and 1 over the winter but it may not be a huge driver of the winter pattern.

The PDO (Warm and cold water pools in the pacific outside the El Nino region) looks to be positive for the winter. This is a good signal if you like colder weather.

Eurasian snow cover is the last factor and we need October to grow. Much of the data circulates around how much snow cover grows in Siberia region. So far, so good-- but we need to let the data fill out. The growth has been good and growth has a strong correlation to - AO. This is usually a sign of cooler winter in our region of the world.

So, my thoughts are leaning colder than normal winter, but not as cold as last winter. Snowfall we didn't really get above normal until that last snow on March 25, so as of now, near normal is a fair call-- which is 17 in LYH and about 20 in ROA (Give or take) As in any winter, a fluke big event could skew that strongly.