Saturday, March 22, 2008

Saturday: Happy Easter! Quiet weather ahead...

I hope all of you have a wonderful Easter tomorrow!

The weather the next few days looks very quiet, but cool. Tomorrow and Monday should remain in the 50's. However, warmer air looks to return once again later on into the middle and later part of next week.

Believe it or not, I got a lot of sun this weekend! It's a good reminder that Spring is here. In fact, the back of my neck is sunburned pretty bad, and my arms too. It is possible to get sunburned in March as well...time for an early start on tanning! (which I did today too.)

Not much rainfall is in store anytime soon. Later next week looks to be our next best shot at rainfall. Until then, I hope all of you enjoy this wonderful weather and I hope it reminds you of the incredible blessings our Creator bestows on us!

One last thing: last post I mentioned some interesting weather showing up on models. At one point, most of the models were showing a potential snowstorm for even the Southeast! What a shock that would have been...but the energy associated with the short wave in Texas appears to be heading more South than East now, so there won't be a storm...at least not around here. However, the Eastern Carolinas may need to keep a very close eye on this one. While the prospects for snow are minimal, there is the chance that a storm may develop close enough to the coast, and with cold air around, it needs to be watched. But as it appears right now, not much if anything will occur.

~Jordan

Tuesday, March 18, 2008

Tuesday: Yet Another Severe Weather Outbreak

:::EDIT:::
1:00 AM Wednesday
Just took a look at the latest 00z GFS run. Very interesting to say the least. :-) I'll update this tomorrow and explain why. Stay safe everyone!
:::END EDIT:::

Good evening everyone! We are now facing yet another severe weather outbreak in the midsts of what has been a very active late winter season...

As the cold front associated with our system coming through, temperatures appear to be rising just ahead of the front before a drop off behind. It is pulling up some very warm and moist air from the Gulf of Mexico. But the question remains, even though the folks to our West are experiencing Severe Weather, will we see it as well?

The question to that is: probably, but not as bad. The instability looks to lack just a little bit' more around our area, but the shear, which has been mighty impressive with just about every system thus far, appears to be very strong again, and it doesn't take much for these winds to get pulled to the surface with a very strong Jet Stream above us as well. So Severe Weather CANNOT be ruled out, especially based on what has happened so far this year.

Taking a quick look at the Storm Prediction Centers storm reports for today, there have only been 30 thus far, but there are certainly more to come. Fortunately only 2 tornadoes have been spotted, one in Texas and one in Missouri. The one in Texas was very minor; only an EF0 in fact. No information on strength with the MO one. But as expected, the wind reports are the greatest, with 26 reports, and I expect that will continue to be the biggest issue as we head into tomorrow as well.

More beneficial rain is expected as well, with probably somewhere between .75" and 1.00" of rainfall. It's nice to see some major progress being made on the rain deficit.

For the rest of the week, things are looking pretty good. We may see a cool down just in time for Easter Sunday, with perhaps some freezing temperatures...? We'll see...not buying it yet.

I will have an update tomorrow on the severe weather if need be. Have a good evening everyone!

Thursday, March 13, 2008

Thursday: Revisiting the Blizzard of 1993


The Blizzard of 1993, also known as the Storm of the Century, was without question the strongest storm to ever strike the Eastern United States. And it brought so much more than just blizzard conditions. Florida reported 11 Tornadoes as a very intense squall line raced through the state. At the very height of the storm, this massive storm created intense conditions anywhere from Central America to Canada! Locally, this storm shut down not only Chattanooga, but most cities anywhere from Birmingham to the Northeast. 20" was officially recorded in the city, but many places outside of downtown received anywhere from 2-4" more. The drifts recorded in some places was astounding, with up to 14' recorded in the highest peaks of the Smoky Mountains. I have provided some satellite images as this storm emerged from the Gulf of Mexico . They really do look like a Hurricane. In fact, at the height of the storm, the central pressure set a record low of 28.35", or 960 mb. To put that in perspective, that is equivalent to a Category 2 or 3 Hurricane. That just shows how powerful this storm was. And as Eric Thomas from WBTV in Charlotte pointed out, "...this may not be just the storm of the century...but the strongest storm in the history of mankind." (Quote found on weathermatrix.)

Check out some of the wind gusts recorded with this storm as well:
Key West, FL: 109 MPH
Mount Washington, NH: 144 MPH
Flattop Mountain, NC: 101 MPH

The storm surge was a huge issue along coastal areas, with many houses being destroyed not only in Florida, but in the Northeast as well. Every major airport on the East Coast was shut down as some point during the storm, which is the first time it had ever happened...and, if my memory serves me correct, has not happened since.

The snowfall amounts were astounding as well;
Mt. LeConte, TN: 60"
Mt. Mitchel, NC: 50"
Snowshoe, WV: 44"
Birmingham, AL: 17"
Atlanta, GA: 4" (more in rural areas)
Albany, NY: 27"
Chattanooga, TN: 20"
Mobile, AL: 3"
Even portions of the Florida Panhandle recorded a few inches of snow, which just shows how magnificent this storm system was as it passed across the Eastern United States.

Even for Cuba, the city of Havana was blacked out for a time as severe weather crossed there region as well.
All in all, over $3 Billion in damage occured in the United State alone, and nearly half the population was affected at some point, along with some 26 states.

Now for the NWS, this storm was quiet an achievement in many ways. For one, this powerful storm was forecast 5 days in advance-the first time a storm of this magnitude had ever been forecast so far in advance. This launched a new numerical model era where significant advancements occured in forecasting due to the impressive consistency provided and the incredible amount of data the NWS was able to use to better make models more accurate in the future...and so far, they have been much better than they were in the early 90's.

I have provided a rough map of where the general areas of snowfall fell, with data courtesy of AccuWeather. Interesting to note that many big cities received more snowfall than most areas surrounding them. Many people wonder if we will ever experience a storm of this magnitude in our lifetime again. I cannot answer that question, but many would agree that this type of storm is a once in a lifetime event...and I can't argue with that. But at the same time, I also agree that the weather is a very unpredictable thing, and anything can happen anytime. Sure it can happen again, and most assuredly will. The question is when. And with that, all I can say is: stay tuned!

Wednesday, March 12, 2008

Quick Update/Tomorrows SOTC Review

Good evening everyone. Got my scanner in, and it's really neat. Anyway, I know I said I would post an article on the Storm of the Century today, but that will have to wait until tomorrow. I need to do some research and stuff, so I'll have that ready by tomorrow evening.

The weather looks about the same as Monday. No big changes as of right now. But I'll keep an eye on it and keep you updated with precise forecasts if not tomorrow, Friday.

I hope you are all enjoying this wonderful Spring weather! Tomorrow promises to be the warmest yet, with perhaps mid-upper 70s!

~Jordan

Monday, March 10, 2008

Monday Evening: Quiet times ahead.

Well, the Saturday winter weather is over, and I think my forecast overall went fairly well. We did pick up 1" of snow up here on Lookout, with some mountains getting more, but the valleys didn't see much. For a period Saturday morning the snowfall sure was impressive, but it didn't last too long. But it sure was cold! But I'm pretty pleased with what transpired compared to the forecast. Wish we all could have had more!! Maybe next winter.

Now the rest of the work week looks rather benign until later on Friday. So until then, enjoy the sunshine and WARM temperatures! That's right, the temperatures look to reach the upper 60's and even perhaps 70's on Wednesday and Thursday. What a treat! The next threat of rainfall appears late this week/early weekend. I'll be tracking that and provide updates as we head closer to the event. With the very warm air, the severe weather threat is a there as well given the storm track. Again, too far away to predict with much certainty right now, but I'll be updating this potential.

Also, I have just purchased a scanner which I should be getting within' a few days. I'll be able to post maps now outlining where I think certain severe weather events will occur...both winter weather and severe thunderstorms. I'm looking forward to it!!

Have a wonderful evening.

~Jordan

Thursday, March 6, 2008

***FRIDAY EVENING UPDATE***

***FRIDAY EVENING***Hello everyone. Sorry for the delay in posting. I wanted to keep last nights post because I also wanted to keep he watch/warning map but didn't want to take the time to repost it. So what's the latest thinking? Well, the NWS has issued Heavy Snow Warning/Winter Storm Warnings for what seems like everyone surrounding Chattanooga. Ha! Even North GA/AL are under advisories/warnings. Locally, up to 2" is being forecast, but I'm going to tell you right now that's not happening...definately not in Valley locations, and I'm not even expecting that up here in the mountains. Perhaps a dusting or so...but radar trends haven't been too encouraging here lately and unless this cold air starts coming in quicker and more precipitation breaks out to our South, I just don't see much. So I'm going against the locals and NWS and saying not much will fall. I could be wrong, but we'll see. As always, these type of storms can be hard to predict.

I'll post later on tonight if more developments occur.

-----------------------------------------------------------------------------------

***THURSDAY EVENING POST***

Good evening everyone. As expected, the models CONTINUE to display poor agreement, and this continues to make for a not so confident forecast. While they are coming into better agreement, especially compared to the last few days, there are still some pretty significant differences that would make a world of difference for some people. There may even perhaps be a blizzard for folks to our north from Kentucky into Ohio, but for us locally, the chance for at least some flurries or very light snow showers exist. The question, as always, is "how much will fall?" And unfortunately, I still cannot answer that question with a great amount of confidence. It is interesting that the 18z NAM and GFS models shifted the low a little bit' Eastward, and I would be very interested to see if the NAM goes totally to a track that would take the low East of the Appalachians. As I stated last night, this model was consistent in taking the low West of the Appalachians right over us. I'll be watching that closely.
However, the deformation zone, or axis of heaviest snowfall associated with low pressure systems in the winter, still looks to be way off to our West, but we might be left with some residual moisture that could fall as some flurries/very light snow IF, and I mean IF, the cold air can come in quick enough. I am confident that as least flurries will fall, if not late Friday night, sometime early Saturday morning. However, amounts look light at best. 18z NAM model backed off on the amount of accumulative snowfall compared to it's previous 12z run...with barely 0.1" of equivalent liquid being recorded, which using an 8:1 ratio, would only be around 1/2" at most, and that to me is even too much. But we'll see as these type of systems sometimes bring some surprises. The GFS is very similar btw.

So that's the way things look as of this evening...which isn't too different from last night. But as always i'll keep an eye on it for ya. Will be interesting to see how much snow places like Memphis get.
BTW: there is a winter storm watch for parts of the central/northern Cumberland Platue, and all of Middle TN. Included in this post is a look at the current watches/warnings. Just click on it to get a bigger picture.

Wednesday, March 5, 2008

American 00z Run Update

Alrighty, I have just finished viewing the NAM and GFS 00z runs...and I must say many questions remain unanswered. It is frustrating and strange to me why these models are so different when the storm is forming later today in Texas! Anyways, the GFS track is mostly the same...with a VERY slight Westward jog, but nothing significant. It is deepening the low a bit' more though...so that is something we'll need to watch closely as the runs continue to come in.

The NAM model is...grrr...frustrating. It is way further West still, and I am still holding on to that happening, especially with the GFS slightly more West...and I am curious as to whether the ECMWF and Canadian models trend way West also. I'll have more tomorrow. I may even post a snow map late tomorrow if I can find the time.

~Jordan

Wednesday: Next Storm

The forecast below is for the Chattanooga area. If you want your region (i.e., Northeast), then please leave a comment below and I will give it my best shot.

Well, after the clouds cleared today, the sun made for a gorgeous afternoon. There was still that fall type feeling in the air though as temperatures stayed in the 50's. And tomorrow promises to be even better with full sunshine and mild temperatures in the 60's! Enjoy it, because we have some major changes coming this way.

The next storm system I am watching will be developing by tomorrow in the Southern Plains with some northern Texas snow and rain elsewhere. This storm is currently in the Desert Southwest but isn't organized at all. We'll have to wait until tomorrow as it heads into the Gulf of Mexico and picks up some moisture. Now on Monday I talked about the fact that the models were all over the place with this storm system. And today, while not nearly as bad, they still have some pretty significant differences...at least enough to make for an "uncomfortable" forecast. The NAM model had been coming into agreement with the GFS, but as of yesterday, it's trying to take this storm up West of the Appalachians as a "Lake cutter", which has been the case just about all winter long. And with the pattern and La Nina, I can very easily see how that happens. The only reason I'm not sticking to that, at least YET, it because most other major models continue to take the storm East of the Appalachians. What's the difference you might ask? Well, if you remain on the Western side of the area of Low Pressure, you are on the "cold side" as well...where the winds come from the North and keep you cooler as the winds around the Low are counter-clockwise, pulling down the cooler air from the north. This is how we get our major snow storms. While that is happening, the low is also pulling up warm air from the South on the Eastern side of the storm. That is why it is critical where the track of the storm is, and also how close the low comes to your area. Typically the worst snows with a storm system occur in what is called a deformation zone where the axis of heaviest snows and convergence occur. A good example of this occured yesterday in St. Louis where the airport received nearly 5" of snow in just 2 hours! Many places received 10-12" by the time the snow ended. This axis of snow is normally a few hundred miles Northwest of the center of low pressure.

Now, what is the current projection? Well, it's still really difficult to say for sure, but right now the most likely track appears to be just to our South heading up into the Carolinas. Normally this would be a classic setup for snow, but there are several things that will play against us this time around. For one, the cold air once again looks to come in too late, and there won't be any cold air ahead of the storm. Obviously that is the most crucial ingredient you need for a storm. Cold air prior to the storm makes all the difference. Granted, if the storm is strong enough it can pull down cold air in time to switch over to snow, and there is still a chance that could happen, but I'm just not seeing much snow right now. While some snow showers could occur, accumulations look minimal at best. But I will keep an eye on this as the setup IS there for a potential snowstorm, but it doesn't look like all the ingredients will come together at the right time for a substantial amount. Anywhere from Memphis to Nashville and Northwest of that up into Kentucky, Ohio, etc. could be in for it though...they will be closer to the cold air source and could see a good amount of snow if things come together in time. But for us, I think the rain should arrive sometime around early Friday morning, but I'm seeing a rather big dry slot occuring though during the afternoon. So we should see a few hours of rain, but the afternoon just looks cloudy, but dry at this point...or at least in my opinion. Now there could be some wrap-around moisture on the back side which is typical for the lows, but there doesn't appear to be very much of it with this storm right now. So expect some rain showers/flurries Friday night into Saturday.

Now, all of this is based on current projections and could change very easily as more model data comes in. Obviously it is very difficult to make a forecast when the models are all over the place, but hopefully they will start coming to a concensus here shortly...or at least a better concensus.

What about Saturday? Well, it looks VERY chilly to say the least, with temperatures perhaps not getting out of the 30's for highs.

I'll have an update out shortly...after looking at tonights 00z runs, I'll make a short post on whether or not I think the current forecast is on track or not.

Till then, take care.

BTW: In case any of you Northeastern folks are reading, I think that this will be an inland runner for you guys as well. But, the cool thing about weather is the fact that it can always change! But I won't write about it unless someone asks me too simply because I do not know how many people from the Northeast, if any, read this.

~Jordan

Monday, March 3, 2008

Monday Evening: Severe Weather possible

As for areas to our West, it's already occuring. There is a lot of unstable air and shear (or "turbulence") in the areas that are currently seeing these strong storms. Fortunately for us, these storms, which will continue to form into a squall line, will occur in our area most likely during the nighttime hours, or early morning hours. And as I've stated before, normally storms weaken when they lose daytime heating. Our air won't be as unstable, but the winds aloft will continue to be very strong, and the trough coming through will become what we call negatively tilted, which may actually enhance some of the storms, or cause a few of them to be severe. So severe weather cannot be discounted in our region tomorrow morning. While not as strong as to our West, this squall line will bring some of the very strong winds to the surface, and a few tornadoes can't be taken out of the picture too because of the shearing winds as well. So PLEASE stay tuned to local stations and if you have a weather radio (which you all should btw), then keep it close by. The morning commute could be stormy. And a second line of storms could come through later on tomorrow during the daytime with the actual cold front, and those could be severe too, if not more severe. So it could be an active day. But the rain associated with it won't last too long, but it will come down hard and fast, so watch for flash flooding if you do happen to get caught under these storms.

Temperatures could fall tomorrow afternoon as the front comes through, but as expected, no snow should fall with this system. The models did indeed continue to trend weaker with the "low", thus the cold air advection won't be as strong, and the backlash moisture should stay well north and west of us too as the "low" will be too far to our West to swing it our way.

Now, what lies down the road? Well, as usual, the models continue to exhibit bad run-to-run consistencies, and they all continue to have there own little solutions. If you were to take the ECMWF model (European model for all you weather peeps out there), then we would have a potential snowstorm anywhere from Northern AL, GA into the Northeast with perhaps a very strong Nor'Easter for you Northeastern folks. However, if you take the GFS solution, then the storm remains unphased with the Northern Branch of the Jet Stream and gets pushed out to sea.
One thing I think is becoming clear though. There WILL be a storm, but where and what happens to it is the biggest question and one I will continue to try to answer as the model runs come out. I for one am hoping the Euro model is right. There are several factors that would support a large storm across the East...and that's why we need to keep an eye on it. Most models do not have a large storm, some do.
Also, the time frame would be late week. I'll keep you posted and have an updated outlook tomorrow. Stay safe everyone!

~Jordan

Saturday, March 1, 2008

Saturday Evening Update

Happy first day of March everyone! As usual it has been a very long while since I have updated the blog, and again I apologize. I will try my best to keep it updated from now on. There is plenty to talk about in the weather department, so lets get right to it. What promised to be a very interesting storm early next week is now beginning to look rather "blah" on the models if you know what I mean. At one point it was looking like a rediculously powerful storm would affect us, but recent models are not deepening this storm nearly as much as they were around our region. Many, if not most, of the models were thinking that we would actually see some snowfall on the back end of the storm on Tuesday after the main rains came through and strong cold air advection occured. However, now the storm looks weaker and thus the cold air intrusion isn't nearly as strong as was being predicted, and since the storm is weaker, the "backlash", or "wraparound" moisture looks very minimal as well. So, our snowfall chances have basically fallen apart here over the last day and a half or so. There is also a chance for the moels to go back to their original thinking, but normally, being this close to the event, they begin to really hammer down on details, so I think the concensus is for a weaker storm with perhaps some strong storms ahead of the front on Tuesday. That is the other aspect of the storm that needs to be talked about also. Many folks, especially to our South, could experience some very powerful storms, especially on Tuesday. In fact, most mets. are very concerned about the potential for severe weather, but I think the biggest threat will be to our South where they do need to keep a very close eye on what could be heading our way come early next week. Knowing how significant the severe weather outbreaks have been thus far this winter season, I'm afraid that this one could be very bad as well. So PLEASE stay tuned for updates. These are very serious events, and I think everyone has learned a lesson about the importance of safety in severe weather threats...namely the terrible tragedies that occured in West TN and so on during the last outbreak.

Now, Tuesday will bring colder weather, but I really don't see much hope for snow across our area. West Tenessee could be a different story, and several inches could fall. But I think if you head especially up towards Paducah, KY is where you'll really start to see the significant snowfalls with perhaps some people seeing more than 8" of the white stuff.

Again, strength of the storm is everything, and right now it's not looking nearly as powerful as it was, but that is something that I will be watching very closely as Tuesday draws closer...any difference in strength and ESPECIALLY location of the Low Pressure center will be crucial to not only our winter weather chances, but our severe weather chances as it comes our way also.

So what about beyond midweek into late week? Well, that's a really hard question to answer right now, as the models have had poor run-to-run consistency, and they all have different solutions. So I'll be updating that as better handling comes along. But I will say that we need to keep an eye on winter weather chances, and cold air appears likely sometime late next week.

I also want to point out real quickly that we are less than two weeks away from the anniversary of the Storm of the Century in March of 1993. As many of you remember, that storm dumped nearly 2' of snowfall in the city of Chattanooga, with even more in surrounding regions. That was an amazing storm, and I plan on writing a little bit' about it on the 13th of March. What a storm...

That's it for now. Will update later!
~Jordan