FORECAST:
Tuesday (High 70, Low 46): Windy. Showers and thunderstorms are likely in the evening and night hours, and a few thunderstorms may become severe.
Wednesday (High 56, Low 48): Partly to mostly sunny. Cold and breezy.
Thursday (High 53, Low 31): Sunny. Cold.
EXTENDED OUTLOOK:
Friday (High 66, Low 35): Partly cloudy.
Saturday (High 65, Low 49): Partly to mostly cloudy with a 40% chance of showers/thunderstorms.
Sunday (High 57, Low 38): Mostly sunny.
Monday (High 65, Low 34): Sunny.
PRONÓSTICO:
Martes (Máxima 70, Mínima 46): Ventoso. Es probable que haya lluvias y tormentas eléctricas durante la tarde y la noche, y algunas tormentas eléctricas pueden volverse severas.
Miércoles (Máxima 56, Mínima 48): Parcialmente a mayormente soleado. Frío y ventoso.
Jueves (Máxima 53, Mínima 31): Soleado. Frío.
PERSPECTIVA EXTENDIDA:
Viernes (Máxima 66, Mínima 35): Parcialmente nublado.
Sábado (Máxima 65, Mínima 49): Parcialmente a mayormente nublado con un 40 % de probabilidad de lluvias y tormentas eléctricas.
Domingo (Máxima 57, Mínima 38): Mayormente soleado.
Lunes (Máxima 65, Mínima 34): Soleado.
NOTES:
We are under a Wind Advisory tomorrow and tomorrow night.
It's a good time to review your severe weather safety plan in case we have any issues tomorrow evening/night. Plus it's just that time of year.
There is a SKYWARN class in Tuscumbia next Tuesday evening (March 11) being held by the National Weather Service in Huntsville. There are also online classes being held by Birmingham and Nashville.
The class I took was rather relatable, as the instructor compared tornado watches and warnings to tacos and when the ingredients were coming together versus when the final product was there.
While the only response I got so far was a standard brush-off e-mail, which did not convince me that the person had actually read much of what I wrote, much less thought about it, I'd still encourage people who care about the issue to write your Representatives and Senators to let them know that we'd like to keep the essential National Weather Service personnel, even if there are other legitimate budget cuts that need to be made to NOAA. Thanks to Dan Satterfield for that reminder. As I say, I half-wonder if my writing those people was worthless, but it's probably worth a try. If enough people speak up, maybe at least a few of these people in positions of authority will take a second look at it. And for what it's worth, Robert Aderholt is already on record telling the press that he's interested in doing the right things here.
While looking for that article, I found an old article about how he opposed things like this even ten years ago, when it was a whole different political world than it is now. So maybe he is someone people in meteorology can count on. I certainly appreciate his support for NWS forecast offices and the like.
The Weatherbrains Podcast will be live on YouTube this evening (that's the show hosted by James Spann and Bill Murray), and I bet the discussion will be lively. This is a serious issue, having NWS offices fully staffed as we head into the heart of severe weather season. And of course after that is hurricane season, affecting a different part of the country usually than the spring-time severe thunderstorms and tornadoes. I'm very interested to hear what everyone has to say tonight. They're interviewing Roger Edwards, who is retired from the Storm Prediction Center. But this is bound to come up. Nobody can avoid the issue at this point, if they tried.
6:04 PM Edit - Actually they had Roger last week, I looked at the wrong show description. Tonight they've got Pete Wolf, who worked in the National Weather Service for 35 years, so still a great guest.
DISCUSSION:
As of 2:35 PM in Cullman, it is sunny and 63 degrees in Cullman. The dewpoint is 16, making the relative humidity 16% - very dry air in place at the moment. Winds are variable today and calm at 3 miles per hour. The pressure is 30.14 inches and falling slowly.
It is sunny and 66 degrees in Jasper. The dewpoint is 18, making the relative humidity 15%. Winds are calm, though they had an easterly breeze earlier. The pressure is 30.14 inches and falling slowly.
Haleyville also has sunny skies and is at 65 degrees. The dewpoint is 21, making the relative humidity 19%. Winds are variable at 3 mph. The pressure is 30.15 inches/996.9 millibars and falling. As usual, props to Haleyville for providing the millibars for those of us who don't feel like calculating the conversion or looking it up every single time. Real weather maps use millibars, but inches of mercury are more familiar to most people.
Elsewhere around the region, Fort Payne is sunny and 63 degrees. Ditto for Scottsboro. Winchester (TN) is sunny and 61. Ditto for Decatur (AL). Huntsville is sunny and 62 degrees with southerly winds. Where most sites are showing Easterly or Northeasterly winds, when it can be narrowed down to one direction today. Muscle Shoals is sunny and 63. Tupelo is mostly sunny and 66. And it is breezy there, winds out of the South at 13 mph with gusts up to 18. Memphis has a pretty good Southeast breeze with mostly sunny skies and 62 degrees. And then Nashville, the music city, is sunny and 61 degrees with light/variable winds.
That Low pressure system and associated fronts along and East of the Rocky Mountains will bring us our high winds and rain/storms tomorrow evening and night. This looks like a squall line event, and it may have a lot less fuel to work with than the one we had in the middle of February. But it's still worth respecting and taking reasonable precautions for.
And it sure was cold this morning, 40 degrees at 6 AM for the radiosonde sounding from Birmingham, 28 degrees in Nashville. We can still have cold snaps like that from time to time in the month of March. It was cold yesterday morning too.
Basically we've got another cold front coming through tomorrow, the same system that is bringing a risk for severe thunderstorms to the Plains today. For us in North Alabama/Southern Tennessee, this looks like an evening and night event. And then on Wednesday the storms move to the Mid-Atlantic Coast.
The upper-level trough will take on a negative tilt tomorrow, and the day should be mostly dry, just windy and kind of warm, High near 70, Low near 45. But in the evening and night, from about 6 PM to Midnight, a squall line of showers and thunderstorms will move through, and some of those could become severe. We'll have some high winds even outside of those storms.
Wednesday it looks like the clouds will be clearing out throughout the day, so partly to mostly sunny skies, still pretty breezy with wind gusts in the 20-30 mph range possible, a High of about 55-56 and a Low of about 47-48.
High pressure in place again on Thursday, we'll be sunny but pretty cold again, High in the lower 50's, Low in the lower 30's.
Some clouds will come back Friday as that High pressure moves to our East/Southeast into the Gulf and Atlantic waters. High temperatures should get into the mid-60's with Lows in the mid-30's.
Saturday another cold front comes in here.
And we'll have to keep an eye on things, because Saturday evening, the GFS brings the strong surface Low in a favorable position to support severe weather around here.
But we're not seeing that from the ECMWF at all. The Low does not look as pronounced, and it's way down close to the Gulf Coast.
So it's something to watch. You have to keep an eye on just about any system this time of year, from now through May.
Another limiting factor is instability. We're looking at a High in the lower 60's and Low in the upper 40's for Saturday, so if that forecast holds, usually you need warmer, muggier air than that for a significant severe thunderstorm threat. Chance of rain is about 30%.
More cold air behind that, or at least a cool shot of air, the High on Sunday in the upper 50's, Low in upper 30's, with mostly sunny skies.
Then next Monday looks sunny with a High in the mid-60's, Low in the lower-to-mid-30's.
Rainfall totals will average about an inch or so for this forecast period.
MESOSCALE DISCUSSION:
This system is now within the reach of the Convection Allowing Models, and the HRRR looks interesting, with some activity forming ahead of the main squall line and moving into Northwest Alabama as early as 3 PM, the main line arriving about 6 PM or so.
But at those same times, it is showing no unstable air to work with. In fact, if these trends continue, tomorrow's event may end up being a line of showers more than storms with just a lot of high winds in and out of the rain. We've certainly had events like that before. The trend of all the models has been to show less and less unstable air to work with as we get closer to this event.
Even later in the night, 9 PM to Midnight, the 3 km NAM is showing very meager, if any instability over North Alabama.
Even though the wind shear is way more than enough.
A forecast sounding makes the chance for severe thunderstorms look marginal at 9 PM for Cullman, Walker, or Winston Counties because of the lack of unstable air.
The SREF doesn't show any unstable air overspreading the area that's even close to 500 j/kg of CAPE until Midnight going into Wednesday morning. And then, sort of like the high-res NAM showed, the best wind shear is also exiting Northeast Alabama by then.
So I don't want to call this event a nothingburger, but it looks more like we're mainly going to have a line, or maybe two lines, of rain, and lots of high winds. A few places might get unstable enough to support isolated thunderstorms, and those could become severe. But a lot of us are probably just going to get high winds, especially as the line of rain moves through.
This mainly looks like a damaging wind threat for us, and some of the wind damage tomorrow might not even be in the line of showers and thunderstorms. I could see some tree and power line damage happening from just the gradient winds in this system.
The worst of this event will likely be focused in Southern Mississippi into parts of Louisiana and Southern Arkansas, where they will have enough unstable air to support supercell thunderstorms that could produce significant wind damage, some large hail, and tornadoes. And some of that risk does extend into Southwest Alabama, including Mobile. Up here, our tornado threat is looking minimal. We're fortunate that it looks like the air up here will stay relatively stable.
The threat for any severe thunderstorms looks a little higher on the Alabama side than North of the Tennessee state line with this one, but everybody could get wind gusts of 40-50 mph even outside of specific showers or storms with this. Just know that's a possibility.
And of course, if you get a Severe Thunderstorm Warning, the best place to shelter is in a small central room (or hallway) on the lowest floor of a sturdy house; it's better if you're not in a mobile home, especially if there are trees around.
The most likely timing is between 6 PM and Midnight for this line of showers/storms to blow through. And really, it may end up being more than one line. There are enough clues in the models to make it look like some showers might get organized ahead of the main squall line and form a cluster or a second line. If that happens, the time it starts could be sooner, like between 3-6 PM for any of those earlier showers or storms. We'd have to watch those closer if they did develop just in case it still being daylight were to provide any surface-based unstable air.
Overall this looks like a low-end severe weather risk, where we're mainly going to have just a good bit of rain and high winds areawide. But even the lower-risk days are worth respecting, enough to have some plans in place in case a few storms get especially rowdy. It's better not to underestimate storms, because as soon as you do, they're liable to throw you a curveball.
All right, everybody stay safe tomorrow, and if you've got stuff on your porch you don't want to blow away, I'd go ahead and bring it in this evening or early tomorrow morning.
And I really like this thing NWS Birmingham posted on their X/Twitter account. A lot of people don't do anything at all when there is a Severe Thunderstorm Warning. And especially if you're in a mobile home or have trees around, that can be a mistake. Even in a sturdy house with no trees around, you have to take into account, when things are blowing around in winds of 60 miles per hour or greater, windows can break out, simple things like that. And people can be injured. That's why even for an event like this, not looking as threatening as what we had mid-February, it's worth respecting the risk. Definitely take shelter if you go under a warning. And everybody is going to have a different level of how much risk they want to tolerate for high gradient winds through the day and night. Just use good sense. Let people know. This isn't a big severe weather threat at all for us, but sometimes people get hurt in the more minor events just because they aren't paying attention. And actually a lot of how people get killed in these events are like what NWS Birmingham posted, that I reposted above, a tree falling on a trailer, or even things you normally don't think about, like a tree being down in the road, and somebody runs up on it in their car before they see it. Those are the main things to look out for tomorrow/tomorrow night.
P.S. Adding this footnote at 5:50 PM - I made a serious mistake that I'm glad I caught. By the time I got around to trying the Spanish translation of the forecast, I'd decided that the rain chance for Saturday needed to be 40% instead of 30%. But then I forgot to change it in the English version. So I've fixed it now. We'll have to see how warm we get that day, and monitor the chance for any stronger storms. Right now the severe weather threat looks low, but you can hardly be too careful this time of year. Didn't like how the GFS was making it look, the track of the surface Low.
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