Archive for southeast winter storm

Late Season Winter Storm for Dixie

Posted in Winter weather with tags , , , , , , , , , , , , , on February 28, 2010 by stormstream

A late season winter storm is taking aim on parts of the Deep South.

Low pressure will roll eastward out of New Mexico & Texas on Monday tracking across the northern Gulf of Mexico, or just inland along the Gulf Coast states on Monday night and Tuesday. Meanwhile, some upper level energy from the northern branch of the jet stream will phase with this system, and give it a shot in the arm as it impacts areas from Alabama to Georgia and into South and North Carolina.

Temperatures are only going to be marginally supportive of snow, and really this could go either way fro areas of Alabama and Georgia. It’s either going to mostly all rain with maybe a brief changeover to snow for a few hours at the end of the event. Or, it’s going to be rain changing to a wet, heavy snow with large snowflakes falling steadily for at least 6 hours and accumulating to several inches. Unfortunately, we probably won’t know exactly how this is going to hash out until the actual event is unfolding on Monday night and Tuesday.

So, as of this time on the Sunday morning prior to the event I am not willing to put out an official forecast, so here is my unofficial thinking: 2 inches for Atlanta, GA, and 1 inch for Birmingham, AL. Mt. Cheaha, the highest elevation in Alabama could pick up 3 inches, and the east and northeast metro of Atlanta could see 3 inches, with maybe some isolated 4 inch amounts.

I’ll give my official thoughts on this system by 11pm EST on Sunday.

Southeast Winter Storm and Cold Wave

Posted in Severe weather, Winter weather with tags , , , , , , , , , , , , on January 3, 2010 by stormstream

It’s not often that we are 4 days away from a winter event in the Southeast, and most of us in the know are feeling reasonably confident about the forecast. Now that this pattern evolution that has been ongoing for more than a month has finally reached its concluding stages, the medium range models are going to handle the pattern reasonably well for the next few weeks. So, not only is this event going to be handled well, the upcoming winter events (one or two could be significant for the Southeast) over the next two weeks will also be handled better than they would have a few weeks ago. This is good news for those of you who make a living forecasting this stuff. I think it is pretty clear that the Thursday/Friday system is going to be a light to moderate snow producer for areas along and north of I-20/I-85. I agree with the general consensus of this being a widespread 1-3 inch snow, with a few jackpot amounts in the 4 to 6 inch range. Here is what we need to focus in on regarding this event: It may not be a big snow storm, but it will be a high-impact winter storm. The cold ground will insure that snow that falls will immediately stick to all road surfaces and create immediate travel problems. For areas where the snow moves in during the day on Thursday this will create a situation where schools and businesses will need to anticipate this and close early to avoid a life-threatening afternoon rush (shades of “Snow Jam ’82”). Then, there is the aspect of out-of-the-ordinary cold. The cold will not be record setting in terms of temperatures, but could approach record levels in terms of its longevity. With such long-lasting cold this will pose a serious threat to folks who do not have adequate heating for their homes, and also for pets outside. Please be sure to take the necessary measures to protect those two groups. Also, make sure to insulate any pipes on exposed outer walls and leave your faucets dripping. Anyone who has ever dealt with busted pipes knows this is an incredible inconvenience as well as being very expensive. Please DO NOT use a torch to thaw out your pipes or you will torch your house. Finally, the snow that falls will not melt off the next day as is the case with most Southern snows. This snow will be on the ground and on roads and parking lots for days. It will get packed down and create very icy and dangerous areas. So, while not a big snow storm, this one will certainly be a dangerous and problem-causing situation during the snow fall and several days afterward. Finally, I want to address the chance for a swath of significant freezing rain to the immediate south of the snow. The fact that this will be a fast moving system should limit freezing rain amounts, but it will still be enough to create glazing and cause problems.

An Wild Weather Weekend for the Southeast with Severe Weather and Significant Snow Likely!

Posted in Extreme Weather Video, Severe weather, Winter weather with tags , , , , , , , , , , , , , , , , , , , , , , , on February 27, 2009 by stormstream

All systems are still go for severe thunderstorms, then snow across parts of the Southeast this weekend, and we are now getting into a range where I can throw out some more specific forecasts with some measure of confidence.

First, I’ll discuss the severe weather prospects for Saturday and my plans to chase the storms and do a live internet broadcast of my storm chase.

It is hard at this point to say exactly where the greatest threat for severe storms will be on Saturday.  The models are pretty much showing the area in Georgia and eastern Alabama along and south of I-20 as being in the threat zone.  However, I’m not sure the models are handling the effects of the large convective system over central AL and GA very well.  Surely this will reinforce the boundary farther south than the models indicate.  Right now, I’m thinking along and south of  line from Macon, GA to Troy, AL will be my target for severe weather on Saturday.

Steep lapse rates, rather low freezing levels, and the potential for rotating updrafts will lead to very real possibilities of large hail.  Also, the shear, divergence aloft and strong 250mb winds will lead to the chance for long-tracked supercells with a chance for a few tornadoes.

The plan right now is for me and my chase partner, Greg Zamarripa, to depart Atlanta at 11:30am and head for either Columbus, GA or Macon, GA as a base.  We will then head out in any direction from there to intercept storms.  We hope to be in our target by 2pm EST.  Storm chaser Mark Aubin will be targeting the Florida panhandle for any severe storm activity that erupts farther south.

I will be broadcasting my storm chase live on the internet on Ustream.tv and Severestudios.com.  Between 11:30am and 3pm I will be streaming live at http://www.ustream.tv/channel/mike-phelps-mobile-weather-stream.  Then, from roughly 3pm EST onward I will be streaming live at http://www.severestudios.com/livechase as Mike Phelps.  On the ustream.tv broadcast the viewer will have the ability to not only view the live video, but also hear audio from within the chase vehicle.  You’ll be able to listen in on critical nowcasting conversations and storm chase strategies, so you’ll actually feel like you are riding along with us on the chase.  There is also a chat feature where you can interact with me via instant message, and I can talk to you live.  The severestudios.com broadcast will not feature audio, but the video could be spectacular at times since we will be streaming at that location during the height of the storm chase.  I will be available to the media for live phone interviews any time at 404-202-6317.

Now onto the snow prospects for Sunday.

This looks to be a classic late winter/early spring upper level snow events for parts of the Southeast.  The upper low drops in from the northwest bringing with it a supply of moisture, cold air and strong dymamics.  These events are notoriously difficult to forecast and the area of heavy snow that falls will be dictated very much by the exact path the upper level low takes.  Right now, I’d say a general trace to 3 inch snowfall looks like a good bet across TN, northern and central AL and GA, much of SC and much of NC.  1 to 3 inches for Memphis, Birmingham, Huntsville and Chattanooga.  1-2 inches for the west Atlanta metro area, and 2 to 4 inches for the east and northeast ATL metro.  3 to 6 inches for Athens, GA.  4 to 7 inches for Greenville, SC.  I won’t venture to throw out a snowfall forecast for Columbia, Charlotte or Raleigh just yet, but they could also make out very well.  I also believe someone in the Southeast is going to see some “jackpot snow”of a foot or more, but it is impossible to pin down who that will be at this juncture.  I hope it is my backyard!  🙂  Now having said all that, I do need to caution that the bust potential with upper level snow systems in the Southeast is very high.  Honestly, we are not going to have a fully confident handle on this thing until it is happening.  The cities I listed above could just as easily end up seeing a lot less, or a lot more.  Definitely a system to monitor closely as there are sure to be several changes in the forecast over the next 24 to 36 hours.

I will also be streaming live video of the snow storm, and I will have more details on that in my blog entry Saturday evening or Sunday morning.

Severe Thunderstorms, then Snow this Weekend for the Southeast!

Posted in Severe weather, Winter weather with tags , , , , , , , , , , , , , , , , , , on February 26, 2009 by stormstream

A wild weather weekend is in store for the Southeast from Friday through Sunday.

On Friday, the stage is set for a severe weather episode across central Mississippi into central Alabama.  Hail and damagaing winds look to be the biggest threats, but there will also be the threat for some tornadoes as well.  If dewpoints reach the 63-67 degree F. range, then even a strong tornado or two will be possible along and just north of I-20 in MS and AL on Friday afternoon and evening.  By early evening the threat for strong to severe storms will extend into parts of western and northern Georgia.

On Saturday, the main threat for severe storms will extend from central and south Georgia into the upstate of South Carolina and central and eastern North Carolina.  Instability will decrease, while upper level dynamics increase.  Overall, the threat on Saturday does not look as great as that on Friday, but nonethelesss, damaging severe thunderstorms will be possible, especially across central GA, and an isolated tornado or two cannot be ruled out.  I may be streaming severe weather video at http://www.severestudios.com/livechase.  If I do, I’ll be sure and let everyone know.

Saturday night through Sunday and even into Monday morning is looking VERY interesting in terms of significant snowfall.  Yes, it does snow in March in the Southeast, in fact, some of our biggest snowfalls happen in March.  this will be a fairly long duration upper level low snow event IF it pans out.  These are notoriously hard to forecast and pin down the areas of greatest snowfall accumulation until the event is actually unfolding.  These events are also notorious for “jackpot snows”, where someone in a small area or narrow swath gets absolutely crushed by heavy snow.  We had one of these early in the season across southern Louisiana into southern and central Mississippi.  I won’t get specific yet, I’ll just say that significant amounts of wet, gloppy snow will be possible across northern and central MS, AL and GA, southern TN, much of SC and central and eastern NC.  Could this threat fizzle like so many have this winter?  It sure could, so it will be important to keep an eye on the forecast and not get too carried away just yet with this threat in any direction.  We’ll know much more about the potential snow threat and more specific details by Friday night and Saturday morning.

Winter is Losing the Battle to Spring in the Southeast

Posted in Severe weather, Winter weather with tags , , , , , , , , , , , , , , , on February 12, 2009 by stormstream

I’m going to mention the operational GFS now, and I know it has not been all that great this winter, but I do feel that it is at least adequate in showing a big picture pattern in a general sense.  It shows a total of seven low pressure systems marching from west to east across the country over the next 16 days.  This kind of very progressive pattern greatly favors any real cold staying locked up north, and that is where most of the major winter storm threats will remain.  Also, in that entire 16 day period, the strongest surface high pressure system depicted in the lower 48 states is a 1035mb surface high in North Dakota on February 22nd.  Mostly, the SHP systems are in the 1022 to 1032mb range.  This would lead to an average to a little below average temperature pattern for the areas where these air masses cover, and that is going to be generally north of the 40 degree north latitude line.

Despite all the favorable MJO, -NAO, -AO, +PNA, WPO, WTF, WTH, BFD, OMG, BYOB, CYA, La La La Nina talk, sometimes you just have to throw all that mumbo jumbo aside and look at the big picture and use common weather sense. I n fact, that has been the absolute best forecasting approach by far all winter long, and I see no reason to abandon what works.  When I do that what I see is our chances for much more in the way of real cold and wintry threats south of I-40 being washed away by multiple rain and severe weather threats over the next two weeks or longer.  Also, the old saying is true, you can’t fool Mother Nature. The fact of the matter is the more direct rays of the sun are striking the northern hemisphere now, and the sun angle is getting higher at a pretty fast clip. It’s getting warmer and warmer.  The Robins have returned. The flowers are starting to bloom. 60 and 70 degree temps are becoming common. And springtime severe weather is becoming more common.  You know, I don’t see anything out of the ordinary going on.  It appears the change of seasons is progressing as it normally does this time of year, and for us in the Southeast a normal progression into spring means a rapidly dwindling chance for any significant wintry weather after about Feb. 20 unless you live above 2,800 feet in the Appalachians, or in North Carolina.  Heck, this winter it will probably snow in May in North Carolina!  So, the northern half of AR, and TN, the mountains of TN and NC, and the northern half of central and eastern NC stand the best chance at seeing any significant winter weather for most of the remainder of the month.

Now that I have spent most of this post throwing a warm, wet blanket on the cold and snow lovers, I will throw out one tid bit of good news for those of us south of I-40.  I do see the overall pattern possibly evolving into one that would support one last-gasp winter event for much of the Southeast in the Feb. 27 – March 6 time frame.  It may very well never come to pass, just like the end of January/early February threat that I saw ended up being bungled by the medium range models, but at least I do see some sliver of hope for a winter’s last stand type of event.  Also, one can never truly with 100% confidence say winter is over until around Tax Day in the South, so keep hope alive!  I haven’t given up, I’m just keeping a realistic head about it and if a big winter storm or major cold blast happens in the next two weeks to one month, then I will be very pleasantly surprised.

Significant Upslope Snow Event for the Central and Northern Mountains of North Carolina and Tennessee

Posted in Severe weather, Winter weather with tags , , , , , , , , , , , , , , , , , , , , , on February 2, 2009 by stormstream

There’s not too much to say about today’s non-system that hasn’t already been said, so I won’t waste any more time talking about it.  I will say that I would not be surprised to see an inch of gloppy, wet snow on the Cumberland Plateau this morning. I’ve driven up to the rest stop on I-24 in Monteagle, TN several times in situations like this, and been rewarded with some nice snowball-making snow.  And as for the second short wave, the clipper, that earlier looked like it could possibly provide parts of the Southeast with a dusting of snow on Tuesday night, well that now looks to provide only some light rain and snow flurries Tuesday afternoon, but will be a major factor in fueling the system that the majority of this blog post will concentrate on.

The cold front moves across the region today.  Light snow will overspread the mountains of eastern Tennessee and western North Carolina, and provide an inch or two of snow for locations above 2,800 feet.  Not a big deal.  The big deal comes Tuesday afternoon and night.

A winter storm watch is in effect for the following counties in the mountains of western North Carolina from Tuesday afternoon through Wednesday afternoon:  Avery, Madison, Mitchell, Madison, Yancey, Haywood, Swain, Buncombe, Graham, Ashe, Watauga, Grayson, northern Jackson, Caldwell mountains, Burke mountains and McDowell mountains.

During the day on Tuesday the upslope flow becomes firmly established across the mountains, and snow shower activity will steadily increase through the morning and early afternoon.  As the afternoon wears on an upper level disturbance will swing through the region and enhance the snow, as well as produce some wind.  That is when things get really interesting for especially the central and northern mountains of TN and NC, and especially west and northwest facing higher slopes.  Snow showers will increase to intense snow squalls and the wind will increase, producing low visibilities and blowing and drifting snow.  This will all generally be after about 2pm, and lasting through Tuesday night.  After that, the disturbance passes, and just general light to moderate snow shower activity will continue through the afternoon on Wednesday before coming to an end around sunset on Wednesday.  When all is said and done, elevations above 2,800 feet in the central and northern mountains of NC, and TN mountains along the border with NC, will have a general 3 to 6 inches of snow on the ground, and the ski resort elevations above 4,000 feet could see up to 8 inches, and possibly more than that in the most favored upslope regions.   Beech mountain, Sugar mountain and Wolf Laurel should make out very well with this event, so skiing will be back in full swing for the TN and NC ski resorts through the upcoming weekend.

Just a quick mention about the cold weather, then the warm up and severe weather chances that I mentioned in my blog yesterday.  We are definitely still on track to see some cold weather Tuesdsay and especially Wednesday.  Lows in the ATL area could drop into the 20’s with teens outside the city, with highs only in the 40’s on Tuesday, and possibly not making out of the 30’s on Wednesday.  Then starting Thursday the warm-up begins, and we are into the 60’s by the weekend.  In fact, this looks to be an awesome weekend coming up for any outdoor activities.  Heading into next week there are still some indications that a pattern that could favor some intense thunderstorm activity for parts of the eastern half of the nation could evolve by the middle or end of next week.  There is no way to be any more detailed than this right now.  This will be something that I’ll be monitoring, and as details come into better focus, I will certainly pass along my thoughts on this, but that probably won’t be until early next week.

Winter Storm Threat is Over for the Southeast. Cold, then Warm this Week. Severe Weather Pattern Developing in about 8 to 10 Days??

Posted in Uncategorized with tags , , , , , , , , , , , , , , , , , , , , , , on February 1, 2009 by stormstream

Ok, as we do so many times here in the Southeast during the winter, it is time to say, NEXT!

What looked like almost a sure thing on the forecast models last Thursday and Friday, now looks like c***. Lesson learned: I don’t care how much consistency is being shown in the models, and I don’t care how many of the forecast models are showing a major storm, DO NOT trust ANY forecast model this winter beyond three days. The performance of the medium range forecast models us forecasters rely on heavily for our extended forecasts, have been laughable at times this winter.

As for the non-storm.. well, it’s going to bring us a little rain. Not much, as most of us see less than .25. No drought relief at all from that. As the rain moves out and the cold air moves in there may be a brief period of flurries where we see a few tiny flakes flying.  Some of us will see no rain or flurries at all.  Quite a disappointment considering what the models were showing late last week.

One area that still looks to get some decent snow will be the mountains of TN and NC. There will be some light snow that develops above about 2,500 feet on Monday, then that will slack off Monday night and Tuesday morning. Tuesday afternoon the “flow snow” as it is called kicks in. That is when moist, northwesterly upslope flow brings a prolonged period of snow showers. Those will intensify Tuesday night into Wednesday morning as a disturbance sweeps across the region, and then snow and wind will become impressive, along with very cold temperatures. In fact, atop Beech mountain and some of the other favored upslope areas, conditions could be called “near blizzard” Tuesday night and Wednesday morning for a time. Total snow accumulations in the mountains of TN and NC will be on the order of 2 to 5 inches, with some favored upslope areas possibly picking up 6 inches, or maybe even more, with quite a bit of blowing and drifting. Actually, if someone wanted to drive and see an impressive snow event then head to one of the NC ski resorts like Beech mountain, Sugar mountain, or Wolf Laurel on Tuesday and spend the night Tuesday night.

This week is going to see some extremes in temperatures. It starts out cool on Monday, then downright cold on Tuesday and Wednesday. By Thursday a warm up begins in earnest, and it is quite mild and pleasant by Friday and Saturday.

Next week, there are some very preliminary indications that a weather pattern could be evolving that would be conducive to severe weather across parts of the Plains and into parts of the East by late next week and/or the week following. The way the medium and long range models have performed, I am hesitant to even mention it, but I want to at least throw it out there as a possibility. It is getting to be that time of year you know.