Thursday, January 11, 2024

Windy, Perhaps Stormy Day Tomorrow, Then Very Cold Temperatures and a Chance at Snow Monday

(Forecast)

Friday (High 63, Low 44): Rain and high winds. Isolated thunderstorms are possible, and some could become severe. 

Saturday (High 45, Low 25): Sunny. Cold and still a little breezy.

Sunday (High 43, Low 22): Mostly sunny. Very cold, especially in the morning. 

(Extended Outlook)

Martin Luther King Day (High 35, Low 24): Mostly cloudy with a 30% chance of snow showers. 

Tuesday (High 27, Low 15): Partly to mostly sunny with a 20% chance of lingering snow showers. 

Wednesday (High 36, Low 9): Sunny.

Thursday (High 45, Low 19): Mostly sunny. 

(Pronóstico)

Viernes (Máxima 63, Mínima 44): Lluvia y vientos fuertes. Es posible que se produzcan tormentas aisladas y algunas podrían volverse severas.

Sábado (Náxima 45, Nínima 25): Soleado. Frío y todavía un poco ventoso.

Domingo (Máxima 43, Mínima 22): Mayormente soleado. Mucho frío, especialmente por la mañana.

(Perspectiva Extendida)

Día de Martin Luther King (Máxima 35, Mínima 24): Mayormente nublado con un 30 % de probabilidad de nevadas.

Martes (Máxima 27, Mínima 15): Parcialmente a mayormente soleado con un 20% de probabilidad de nieve persistente.

Miércoles (Máxima 36, Mínima 9): Soleado.

Jueves (Máxima 45, Mínima 19): Mayormente soleado.

(Notes)

It would be a good time to review Winter Weather Safety as well as Severe Weather Safety

We have been put under a Wind Advisory for tomorrow, and it is important to remember that high winds will be capable of producing some power outages even apart from any specific showers or thunderstorms. 

As always, if anybody sees room for improvement with my attempts at duplicating the forecast in Spanish, please feel free to leave a comment and get in touch. I used to be really keen with it and hate for that knack to go to waste, especially since there has been so much talk about there being a communication deficit in that regard in the weather community. For now, I'm using Google Translate and then going through and fixing all the errors I can catch. But I am not a native speaker. With this particular forecast, I realized I'd forgotten the words for snow. It is something I am trying, more often than I try those 10-Day-Outlooks. 

(Discussion)






Overall we had a sunny and mild day in the Tennessee Valley. Winds were generally from the South/Southwest, and it did get a little breezy at times. The seriously high winds will move in here overnight and tomorrow. 

The High in Cullman was 61 after a morning Low of 36. Jasper saw a much sharper contrast in the morning and afternoon temperatures, a High of 64 and Low of 25 there. Haleyville saw a High of 61 and a Low of 33. 

Fort Payne's observations all appear to be from yesterday, so we'll just pass over that. Decatur had a High of 62 and Low of 34. Gadsden is another spot that saw quite a range of temperatures today, High of 62, the morning Low all the way down at 24. Huntsville saw a few more fair-weather clouds today than most other places around the region, had a High of 61 and Low of 37 there in the Rocket City. Muscle Shoals saw a High of 63 and Low of 40. 

Elsewhere around the region, Tupelo had a High of 64 and Low of 37, as far as I can tell, but a lot of their observations from this morning are missing. Memphis saw a High of 66 and Low of 38. And Nashville, the Music City, had a High of 58 and a Low of 39 today. 

That fast-moving storm system out over the Plains will affect us tomorrow, perhaps starting fairly early in the day. There are changes to the forecast since yesterday, so let's look at things in detail. 



That is a strong low pressure system, and it will bring snow to the Midwest into Great Lakes region. We are on the warm side, and it will bring us a lot of rain and wind, and maybe some storms as well. The risk for severe weather is dicey with this system for North Alabama and into Tennessee, but the potential is there. Expecting a high of about 63 and a Low near 45. The rain is not expected to be excessive tomorrow with the system moving so far, but we do have that low-end severe thunderstorm potential. And the main thing is the strong gradient winds. It may be worse than the other night by a little bit, kind of like that high wind event back in March of last year, I think it was. Just prepare for sustained high winds that could gust up to 40-50 miles per hour or so. The power may go out for some of us from that. So make sure you've got batteries for your weather radio and whatnot. Might consider charging the batteries on your phone ahead of time, just in case you're in one of those places where the power is out for a little while. We saw power outages the other night from these kinds of gradient winds. 



Then for Saturday, cold dry air blows in here in a hurry. It will still be breezy, gusts up to about 15-20 mph possible, but nothing like the day before. Winds should shift around to the West before turning more North/Northwest. Skies should be sunny, and the High might get up to about 45 degrees, expecting a Low near 25 in the morning. 



Then on Sunday, we'll start out even colder, lower 20's in the morning, and only warm to about the lower 40's, probably will not make it to mid-40's despite skies staying mostly sunny. It is now looking like the chances for even light snow showers moving in will come after midnight, and that is technically Monday, so will not be including any precipitation chances for Sunday in the official forecast, even late at night. 



Of course all the buzz is about Monday, which is Martin Luther King Day (actually falls on his birthday this year, thought that was kind of neat), when schools will already be out for the holiday. Will we see snow (or ice), and how much? 

The GFS does look favorable for it, with enough cold air filtering in here ahead of the precipitation that certainly for the counties across the Tennessee border, some decent snowfall is a good possibility, but something we have to watch in North Alabama too. We could fall in that zone. It is a little early to tell since we still have tomorrow's system to get out of the way, two powerful storm systems lined up in a row here. But these are the trends. 


The ECMWF at Noon Monday supports this idea of some snowflakes falling. 



And there is actually good agreement from the Canadian GEM between 6 AM and 6 PM Monday. 

We are likely to start the day down in the lower-to-mid-20's and then only warm to about the mid-30's. If we do warm above freezing, then there could be a mix of rain and snow. And depending on several factors, some places could see some ice, although the model runs today and some yesterday have suggested the possibility of a sleet/freezing rain mix less than a few days ago. Most of this will probably be rain or snow. And my gut feeling is that if snow gets going early in the day, by late morning, then that will keep temperatures from warming. Some of us might still be in the lower 30's or colder than that, especially across the Tennessee border. Confidence is increasing that this will bring a chance for accumulating snow. 



The GFS is showing some wraparound moisture behind this strong front on Tuesday at Noon, still snow showers possible at least up in our Tennessee counties. 


The European model does show some of that, actually a line of snow that stretches back into Mississippi and maybe West Alabama at Daybreak Tuesday (6 AM). But as far as the big dump of snow it suggested yesterday for Monday night into Tuesday, that idea is gone now. 


And the Canadian actually shows showers (would be snow showers given the temperature profiles) lingering for all of us in the Tennessee Valley at 6 AM Tuesday. 

So this is a challenging forecast, as forecasts involving snow around here usually are. We are now four days away from the event. So this weekend, any offices that are going to issue Winter Storm Watches or Winter Weather Advisories are probably going to do so Saturday or Sunday. 

Tuesday looks brutally cold whether we get the lingering showers or not, Highs in the 20's and Lows in the Teens. I tend to think we will have some snow showers lingering Tuesday morning, more so in Tennessee, but probably some on the Alabama side too, North Alabama anyway. 



Then on Wednesday, high pressure approaches the region again, and we will see enough sunshine that the High may get back up into the 30's. But we will still start the day very cold, probably down in the single digits for the Low. And I will just add that for any areas that were to see any fairly significant snowfall, sometimes that snowpack can keep temperatures down. That would be more likely up into Tennessee but would not be out of the question for at least isolated parts of North Alabama. There are many unknowns at this point in time, but the potential for accumulating snow on Monday is real, and could last into early Tuesday for some of us. 



Thursday we have strong high pressure parked around Mobile, and we still stay cold and dry. Looks like the High could get up into the 40's again, but the Low should still be down around 20 degrees or slightly lower. 

Go get ready for some seriously cold weather next week. This will be an Arctic blast. And I think we'll see some snow with it. It's just too soon to be really detailed about where gets what impacts, and when. 

Hopefully this post gets the basic ideas across, but it's important to keep checking back with sources you can trust between now and the event. After tomorrow's system is on out of here, forecasters will be able to nail down a lot more of the details. But let's be honest about the fact that we don't see snow all that often around here (further up into Tennessee, you do, but Southern Tennessee into North Alabama, not all that often), and that when we do, it can be challenging to predict placement and amounts. And with this, it has been tough to determine what type of a wintry mix some places might get. Now I'm leaning toward mostly snow for North Alabama and certainly as you get up into Tennessee. Could be some sleet in there, but overall I'm leaning toward our changeover from rain to snow being a pretty smooth one. But we are still four days out from the event. We'll see what details we can have confidence in this weekend, after tomorrow's system is out of the way. 



About tomorrow's severe weather threat, the Storm Prediction Center has backed off on it overall and blanketed us with a basic 15% risk for severe thunderstorms for the most part. The thermodynamics are no longer expected to support that long corridor of supercells all the way up into the Carolinas. It is one of the most drastic and quickest changes to one of their forecasts I've seen in a while. 

The one enhanced area does include parts of Northwest Alabama though, and that is a 30% chance for particularly damaging winds in thunderstorms. They are thinking enough convection can get going in Northern Mississippi into Northwest Alabama to enhance the high winds already going on and perhaps even bring winds in some thunderstorms up to about hurricane force, which of course can do fairly significant damage, similar to what a tornado could do. And we do have a basic 5% risk for isolated tornadoes all across our area, as well as a 5% marginal risk for large hail. 



I think the enhanced threat area over Northwest Alabama is probably because some of the Convection Allowing Models were showing a sort of mini-squall line developing in that area tomorrow. I don't put a lot of stock in that, since the model guidance has really struggled with this. But they do have to draw the boundaries somewhere. I'd be more inclined to think that most of us have that basic risk for severe winds and maybe an isolated tornado, only a marginal risk of any severe hail with such limited instability. And that isolated spots around the Tennessee Valley may see a more significant wind event. If I was drawing the maps, I don't know that I'd localize that for the same area the SPC did this time. I would probably just note in the discussion that isolated more significant spots of severe weather were possible over a much broader area. But I almost always defer to their judgement. Always take my opinion with a grain of salt. If any storms can develop supercell characteristics, those are the most likely to produce a tornado somewhere, but it is looking like this will be more of a damaging wind event, most of that potential for wind damage perhaps occurring from just the gradient winds, outside of any specific thunderstorms. 

Here you can see the NAM struggling to find a decent combination of instability and wind shear tomorrow between Noon and 3 PM. 




Between Noon and 6 PM, it is also showing CAPE values staying below 500 j/kg. Which even with crazy-high wind shear and a strong source of lift, often is not enough to work with to get severe storms that sustain. 



The SREF also shows the CAPE staying below 500 joules. And I checked some other parameters like Lifted Index, similar look. 


Not seeing much in the way of Significant Tornado Parameter values until you get into South Alabama. There is that one isolated pocket in Tennessee. And it is easy to see why the SPC blanketed such a large area with just a basic damaging wind/isolated tornado threat. And that one area, they enhanced for wind damage potential. But overall they took a blanket approach since there is potential, and over a wide area, but model guidance hasn't given us a whole lot of consistent clues that help narrow it down or determine where the threat might play out the most. 



The main reason I am feeling skeptical about tomorrow's severe thunderstorm threat is this, the dewpoints generally staying below 60 degrees all day. If that verifies, then we are looking at just an issue with the high gradient winds, not convectively enhanced damaging winds. 


And it seems like a day or two ago, the ECMWF was showing some higher dewpoints and instability. But now it is on board with the idea that at least for North Alabama up into Tennessee, dewpoints will stay below what we'd look for to have severe weather problems. 

So most likely if you have issues tomorrow, it will come from high winds that are just the result of this being such a strong low pressure system moving through. However, there is a chance that a few thunderstorms could develop. If and where they do, they could become severe, enhancing the potential for wind damage. And it is not out of the question for at least one or two places to see a tornado try to develop. Even though instability is going to be marginal at most. 

If you get a severe thunderstorm warning tomorrow, best thing to do is get into a small interior room on the lowest floor of a sturdy house. And if you live in a mobile or manufactured home, then you might consider spending the day with someone who has a sturdier house, especially if you've got trees around. 


Rainfall amounts will probably stay under an inch for most of us with such a fast-moving system. 



As we get into Monday of next week though, we will have to consider the possibility of accumulating snowfall for the Tennessee Valley. Check the sources you trust (the best might just be the National Weather Service, your local office) this weekend to see if any winter weather products are required. 

And if you do go to stock up at the store, I'd skip the milk and beer. Non-perishable foods (and make sure you have a hand-held can opener) and bottles of water are better ideas, and so are things like a flashlight, battery radio, basic first-aid supplies, medicines for anybody who might be low on them, simple games to keep any kids entertained, or even a good sleeping bag in case the heat were to go out for a little while. Sometimes during extreme cold, power companies will do "rolling blackouts." I remember that from December of 2022. 

And this may not be that big a deal for a lot of us. But preparedness is always a good idea. If you want to stock up on some peanut butter and crackers, or make sure the older folks have their blood pressure meds (or their geritol . . . har har har), nothing wrong with that. The National Weather Service likes to say that in extreme cold, you need to remember the five P's.

People
Pets
Plants
Pipes
Practice heat safety.

This is definitely going to be the kind of weather where pipes could burst or someone outside could freeze to death. So you wouldn't want to neglect any pets, of course, and if you know somebody who's homeless and wanders around all the time, if they're not some total thug you can't trust, maybe make sure they have a roof over their head when the cold gets dangerous like this. Or at least let them know about any warming centers that are open. I find I'm not too crazy about the idea of anybody turning into a popsicle out there. 

As far as the heat safety, it is important to be careful if you have backup methods of heat other than electrical. You have to be careful about carbon monoxide even with some traditional fireplaces, great as those can be. And as luck would have it, I had a reminder today of how easily a house fire can start from seemingly harmless circumstances. Serves a bachelor right for thinking he can fry onions efficiently. I managed to starve that stovetop fire enough to bring it down, and then blow the rest of it out like a birthday cake. I don't have a fire extinguisher, and if it had caught up any more, I was going to call for a fire truck and get my keister out of here along with the beloved cat, Salem. Fortunately I was able to stop it before it got to that point. But that makes me even more inclined to tell people to please be careful. Just take some common sense precautions for this cold spell to avoid some of the bad scenarios. They might not happen anyway, but an ounce of prevention . . . is a good thing. 

On a lighter note, we sure did have a lovely sunset this evening. Had just the right amount of clouds and all. I didn't snap a picture, but I'm sure you can find them all over the social media sites. And Salem looks so peaceful that I will not disturb his slumber with a picture. Besides, the man enjoys his privacy sometimes. He did play a lot of fetch today. And ran out of the room when that fire tried to catch up from one of the stove burners. He doesn't like the toy mice I've gotten him all that well, or the really neat toys some others have gotten him. Rarely plays with his squeaker toy or the ball that lit up (I think he bit it until it quit lighting up within a day or two). But loves these frizzy little blue balls that I can't even remember buying or having given to me. He loves to play fetch with those. And will even wake me up sometimes to ask me to throw them. There used to be a guy J.B. Elliott who wrote columns about his dog, Miss Molly. So from time to time, I've written about my cats. I don't know if anybody enjoys that or not. I lost two of them in the space of a year, both died in particularly unpleasant ways. So this guy gets some extra love, whether he deserves it or not. Most the time, I think he does. The lady who donated him to me named him Salem. But he sure looks the part. He had to have his hip operated on right before Halloween. How's that for luck?

Warm wishes. If we do have any severe weather, I don't know how many updates I can post tomorrow. This computer shuts off if it's unplugged for even five minutes. And actually thanks to this cat's wildness, my really good computer is currently down for the count, damaged by some hot cocoa I never expected to find overturned onto the laptop. And "really good computer" is a relative term for me these days anyway. I'll see what I can do tomorrow, but I'm hoping that severe storms are not that much of an issue for North Alabama or Tennessee. The high winds are going to be rough enough by themselves. 

If it does snow Monday, it will be Salem's first. I expect he will be fascinated by it. 

No comments:

Post a Comment

A Cold Snap For Now, Then Warming Up Again with Unsettled Pattern

FORECAST: Tonight (Low 29): Mostly cloudy. Cold and breezy. Tomorrow (High 53): Partly sunny. Cold and breezy. Friday (High 52, Low 40): Sho...