Deep South Winterwx Discussion 2015-2016

[BigB0882]

I am going to go ahead and assume any winter we had is as good as it gets. November was probably our winter. I suppose something could happen in February but all this potential in the coming days is about as good as it gets and we are missing out. Doubt we get the chance again. I suppose I shouldn't complain, though, last year was quite the winter (if you like ice).

[Kennethb]

It is too early to give up on winter. The pattern is set, but just not our turn yet. The GFS keeps wanting to build these large highs in the longrange. I remember 1988 walking around January in flip flops and shorts while Chicago (watching WGN TV) froze. Then in early February is snowed here in Baton Rouge twice in 3 days. Remember last winter. Our first of 4 wintry events did not occur until January 24.

[CYCLONE MIKE]

Ive about given up on a "real" winter for us. Last year was it. This pattern reminds me of the past few hurricane seasons where a lot of people kept saying give it two weeks we're only in august, then wait til end of august things are going to pop, then in September just in time for the peak. Then of course before you know it peak came and it was just wait til next month. Anyway point is it all started with the supposed storm for nyd and while the gfs was right with a storm temps arent even close nor will be, talking our area not west and central tx. Cold air never made it south and east even though some kept insisting it would. Low 70's for Saturday for us And of course 10 days from now gfs shows another massive winter storm for Texas and LA. I'm sure by next week will be showing round three again for the end of the month. I do think the gfs is doing a pretty good overall for the systems though. Long range obviously not with all the gulf coast blizzards but after a day or two after getting rid of that nonsense it has the pattern pretty well locked down.

[SeGaBob]

This is for my area, but this could be a good trend for a lot of the deep south.


AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
1050 AM EST THU JAN 1 2015

.LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/...
A DAMPENING SHORT WAVE WILL PUSH EAST THROUGH THE CAROLINAS SUNDAY
NIGHT AND KICK THE COLD FRONT INTO THE ATLANTIC...TAKING WITH IT THE
REMAINS OF CONVECTION. A BROAD TROUGH WILL THEN DEVELOP ALOFT OVER
THE EASTERN HALF OF THE NATION FOR THE EARLY AND MIDDLE PART OF NEXT
WEEK...AS STRONG SHORT WAVES PERIODICALLY ADVANCE THROUGH THE
NORTHERN TIER OF STATES. BEHIND THE COLD FRONT A ROBUST 1050 MB HIGH
IN THE SOUTHERN PLAINS WILL BUILD EAST THROUGH MID WEEK...PROVIDING
US WITH MUCH COOLER AND DRIER CONDITIONS. EVEN COLDER ARCTIC AIR MAY
BE LURKING JUST UPSTREAM AS A COLD FRONT LIKELY MOVES IN NEXT
THURSDAY.

[BigB0882]

I saw a GFS run the other day that showed arctic air funneling south and east. However, it was 2 weeks out so I assume it will change and probably already has but maybe the pattern will change.

[northjaxpro]

A very good post SeGaBob and an excellent discussion from the mets at the Charleston, SC WFO.

Initially, about a week ago, the models were hinting that a pattern change may occur during the Jan 6- 8 period, but they backed off that idea with the Caribbean ridge established.

I just took a look at this morning's EURO long range runs and there is a very impressive area of arctic air loading up over NW Canada and diving east and southeast down into the Great Lakes region and into the Plains within a week out from now. The models can swing back one way or the other very quickly. It would not shock me to see later runs showing the Caribbean ridge re-establishing itself in the long range. But, will watch to see if the trend toward the Eastern CONUS trough can finally set up as we look ahead a week out. The arctic air is reloading and if we can get just even a slight negative dip of the NAO in the next 7 days or so out, we may get finally a cooler pattern more representative of what we should see in January. Definitely worth following the next several days.

[BigB0882]

Remember last winter. Our first of 4 wintry events did not occur until January 24.

Are you sure it was that late in January? I could swear the first event was very early January, around the 5th or 6th. I don't know why but the 24th seems so late. Crazy to think we had so much action in such a short amount of time as winter is usually over with down here by the end of February.

[Kennethb]

Remember last winter. Our first of 4 wintry events did not occur until January 24.

Are you sure it was that late in January? I could swear the first event was very early January, around the 5th or 6th. I don't know why but the 24th seems so late. Crazy to think we had so much action in such a short amount of time as winter is usually over with down here by the end of February.

Here is an e-mail to a good friend/met:

Incredible as it was, January 24, 2 PM it was 25 degrees with freezing rain and sleet. We had about 18 hours of falling precipitation. It did begin as moderate snow around 12:30 am for about 1/2 hour before changing to sleet and freezing rain, ending around sunset. We were just so close to an incredible snow fall. There was a warm wedge about 9,000 feet above. In 1989 we were in the low to mid 20’s middle of the day, but we had major CAA.

And only 4 days later it was 28 degrees at 2 pm with more of a sleet event storm. About 9 hours of wintry precip. We had some periods of heavy sleet. Again, another inversion above that kept us from another incredible snow event. State offices in Baton Rouge were closed for 3 days.

Then on February 6 a few flakes with light sleet for a few hours around midday. This would have been a noteworthy event if not for the previous 2. The temps stayed just above freezing, so no accumulation or road closures.

And then when thinking about a March 4 Mardi Gras, you would think it would be one of the warmest Mardi Gras days. Yet at noon it was 31 degrees with a moderate freezing rain. A few degrees colder or perhaps earlier in the season, it might have been a major icing event. Still we had a very decent glaze in the city. Really one of if not the biggest freezing rain events I have seen. You and I have seen other freezing rain events over the years here in Baton Rouge, but not like this. As you are aware, freezing rain events are rarer than snow here in Baton Rouge and even hard to obtain in January and February. Another season of one in your lifetime weather events.

[CYCLONE MIKE]

Here is an e-mail to a good friend/met:

Incredible as it was, January 24, 2 PM it was 25 degrees with freezing rain and sleet. We had about 18 hours of falling precipitation. It did begin as moderate snow around 12:30 am for about 1/2 hour before changing to sleet and freezing rain, ending around sunset. We were just so close to an incredible snow fall. There was a warm wedge about 9,000 feet above. In 1989 we were in the low to mid 20’s middle of the day, but we had major CAA.

And only 4 days later it was 28 degrees at 2 pm with more of a sleet event storm. About 9 hours of wintry precip. We had some periods of heavy sleet. Again, another inversion above that kept us from another incredible snow event. State offices in Baton Rouge were closed for 3 days.

Then on February 6 a few flakes with light sleet for a few hours around midday. This would have been a noteworthy event if not for the previous 2. The temps stayed just above freezing, so no accumulation or road closures.

And then when thinking about a March 4 Mardi Gras, you would think it would be one of the warmest Mardi Gras days. Yet at noon it was 31 degrees with a moderate freezing rain. A few degrees colder or perhaps earlier in the season, it might have been a major icing event. Still we had a very decent glaze in the city. Really one of if not the biggest freezing rain events I have seen. You and I have seen other freezing rain events over the years here in Baton Rouge, but not like this. As you are aware, freezing rain events are rarer than snow here in Baton Rouge and even hard to obtain in January and February. Another season of one in your lifetime weather events.[

Ahhh the memories of a real winter. That is why I don't buy into all the hype of this winter being like '89 or even last year for that matter. Models can show it 10-14 days out all day long but we see what really happens. Highs in the low 70's today and just last weekend had a snowstorm for us Even the storms last year greatly underachieved for what the forecast and models were showing but that is another discussion for another day. Anyway as you said its once in a lifetime stuff and not going to repeat itself this year.

[NDG]

So can we say that this is another winter in which the EPO is in control of the US temps?
NAO and AO both positive over the next 7-14 but yet much of the eastern US could see some of the coldest temps so far this winter.
Luckly for us in central and southern FL the positive NAO will keep the core of the Arctic air north of us and we may once again escape freezing temps.

[SeGaBob]

northjaxpro, what do you think of this?


12Z GFS (120 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_mslp_pcpn_frzn_seus_20.png

Parallel and regular GFS have shown this the past several runs if you watch their loops. Maybe some could shift onshore?

Also check this out even though it's long range...

12Z GFS (312 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_T2m_seus_43.png

[NDG]

doubt that will happen over the very warm gulf steam waters, probably in areas closer to the coast. Back in Jan 2010 if memory serves me correct Daytona Beach reported snow flurries off of Ocean effect snow snow bands, but usually the further offshore you go over the warm Gulf Stream the air modifies and the snow flakes melt before reaching surface.

[BigB0882]

Temps are looking mighty cold over Louisiana later this week. Lows in the lower 20s and highs barely reaching 40 for Wed night and Thursday. Is the ridge just relaxing enough for this cold air to make its way to us, is this a sign of things to come or just a hiccup? Any chance at all we can get a coastal low to pop and surprise us with some snow during those cold nights?

[northjaxpro]

northjaxpro, what do you think of this?


12Z GFS (120 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_mslp_pcpn_frzn_seus_20.png

Parallel and regular GFS have shown this the past several runs if you watch their loops. Maybe some could shift onshore?

Also check this out even though it's long range...

12Z GFS (312 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_T2m_seus_43.png

Well, with such a large, strong and massive Arctic High (1050+mb) building down into the much of the Eastern CONUS by the latter part of this week, That cold arctic air mass will spread over the Atlantic and an onshore flow looks to develop as that HP moves eastward. Now, I alluded to this in the Florida thread and that is positioning of this Arctic High later this week. The HP could shift a bit farther south and east, and if that happens, the onshore flow would be delayed a bit from developing here across Northeast Florida. NDG was right earlier regarding a set up Similar to what was depicted in the GFS 120 hour run you posted SeGaBob. Daytona Beach/ Volusia County did see snow flurries with an onshore flow picking up moisture when an Arctic HP dome built into the SE US and moved east. I am not expecting that to happen with this upcoming event later this week here, but, it is a slim plausible chance in this type of set-up.

[hurricanehunter69]

Albeit a slim one...It appears we have a shot...? GFS at 150 hours http://www.twisterdata.com/index.php?pr ... hive=false

[SeGaBob]

northjaxpro, what do you think of this?


12Z GFS (120 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_mslp_pcpn_frzn_seus_20.png

Parallel and regular GFS have shown this the past several runs if you watch their loops. Maybe some could shift onshore?

Also check this out even though it's long range...

12Z GFS (312 hours) http://www.tropicaltidbits.com/analysis/models/gfs/2015010312/gfs_T2m_seus_43.png

Well, with such a large, strong and massive Arctic High (1050+mb) building down into the much of the Eastern CONUS by the latter part of this week, That cold arctic air mass will spread over the Atlantic and an onshore flow looks to develop as that HP moves eastward. Now, I alluded to this in the Florida thread and that is positioning of this Arctic High later this week. The HP could shift a bit farther south and east, and if that happens, the onshore flow would be delayed a bit from developing here across Northeast Florida. NDG was right earlier regarding a set up Similar to what was depicted in the GFS 120 hour run you posted SeGaBob. Daytona Beach/ Volusia County did see snow flurries with an onshore flow picking up moisture when an Arctic HP dome built into the SE US and moved east. I am not expecting that to happen with this upcoming event later this week here, but, it is a slim plausible chance in this type of set-up.

Ok, thanks... it was a bit interesting to see because if it happened it would be cold enough down where you live as well. By the way, our high is supposed to be 39 Thursday according to the NWS.

I always appreciate your replies.

[northjaxpro]

Anyime SeGaBob. Always enjoy chatting with you, especially regarding extreme events like these arctic outbreaks and the tropical season as well.

Yeah, as of right now, NWS is calling for max temps Thursday in the mid 40s. Now, this could change as time progresses. Leading into the event later this week. Minimums in interior North Florida forecasted currently to be in the low-mid 20s, especially Friday morning. This will have to be watched carefully as the week progresses as well.

[northjaxpro]

Well, here is a quick heads up for my neighbors across the Deep South. Things could get rather interesting by late Friday into this weekend for some of you in the Deep South, depending upon a couple of very important factors which are already evolving right now.

First, the arctic air mass on the way for the Deep South. Of course, a very cold arctic air mass (1050+mb HP) is surging south and east out of Canada and will be in the Central Plains by Wednesday morning. The cold arctic air will be locked in across the Deep South for the rest of the week. However, the question will be how fast this cold air will modify by this weekend. Often times, big massive Arctic Highs like this one dropping down are modified too quickly by the models, and that may play a big factor this weekend.

The second major factor involves the subtropical jet, which looks to become active late this week and into the weekend looking at the models. The southwesterly flow aloft will drive in moisture and ripples of energy potentially over the shallow cold dome in place across the Deep South. While at low levels the air will probably be too dry initially for precip to reach the ground, the mid levels let's say above 700 mb may get saturated enough over portions of the Deep South from Northern MS east-northeastward to the Carolinas for the possibility of wintry precip. Since likely at 850 mb level the warm nose (warm advection) will be occuring by this weekend, any precipitation that falls will likely be in the form of sleet or freezing rain.

Now, this is just something to keep an eye on for the upcoming weekend. I will point out though to watch closely as the week progresses how the models handle the shallow arctic air mass. As I touched on in the opening paragraph, models often struggle with the synoptics of handling large arctic airmasses. If the shallow arctic air mass holds firmer than forecast, and the moisture comes in from the STJ late this week, there could be a potential problem over areas of the SE US this weekend.

[northjaxpro]

Some very cold temps on the way for the region as the massive Arctic High (1050+mb) is on the way. By Thursday morning, some areas may see their coldest readings of the winter season to this point across the Southeast U.S.

Minimum temps are forecast to drop into the single digits on Thursday morning across the Tennessee River valley and well down into the teens across Northern MS, AL, and GA and across the Piedmont of the Carolinas. Temps well down into the 20s will occur all the way down to the Gulf Coast region and across Northern Florida.

This may change, so will monitor closely.

[SeGaBob]

Well, here is a quick heads up for my neighbors across the Deep South. Things could get rather interesting by late Friday into this weekend for some of you in the Deep South, depending upon a couple of very important factors which are already evolving right now.

First, the arctic air mass on the way for the Deep South. Of course, a very cold arctic air mass (1050+mb HP) is surging south and east out of Canada and will be in the Central Plains by Wednesday morning. The cold arctic air will be locked in across the Deep South for the rest of the week. However, the question will be how fast this cold air will modify by this weekend. Often times, big massive Arctic Highs like this one dropping down are modified too quickly by the models, and that may play a big factor this weekend.

The second major factor involves the subtropical jet, which looks to become active late this week and into the weekend looking at the models. The southwesterly flow aloft will drive in moisture and ripples of energy potentially over the shallow cold dome in place across the Deep South. While at low levels the air will probably be too dry initially for precip to reach the ground, the mid levels let's say above 700 mb may get saturated enough over portions of the Deep South from Northern MS east-northeastward to the Carolinas for the possibility of wintry precip. Since likely at 850 mb level the warm nose (warm advection) will be occuring by this weekend, any precipitation that falls will likely be in the form of sleet or freezing rain.

Now, this is just something to keep an eye on for the upcoming weekend. I will point out though to watch closely as the week progresses how the models handle the shallow arctic air mass. As I touched on in the opening paragraph, models often struggle with the synoptics of handling large arctic airmasses. If the shallow arctic air mass holds firmer than forecast, and the moisture comes in from the STJ late this week, there could be a potential problem over areas of the SE US this weekend.

So not quite this far south then?