Multi day severe weather week ahead

A lot of the attention for the week, including on this site, has revolved around the eclipse and whether or not we will be able to view it, even if we are in the axis of totality. The story for the rest of the week will follow a lot of the same territory, but will instead surround the threat for tornadoes and other severe weather.

A sharp upper level trough is moved into the Plains yesterday and isn’t really related to the inclement weather obscuring the sky during the eclipse. As it moved in, surface low pressure attempted to organize in west Texas that afternoon and evening. While access to moisture was be limited, access to potential energy was not.

In a scenario like this, you might see some “LP” or Low Precipitation supercells, which are the type that produce the photogenic tornadoes moving through open fields that you see in textbooks. The feature didn’t have enough tight circulation to introduce a bunch of tornadoes, but the updrafts were there, and even without much rain falling, we saw some jumbo sized hail.

It will be more of the same today, but with the bullseye shifted to east Texas and western Louisiana. Additionally, the threat for tornadoes, though perhaps not gigantic twisters, will increase in this area as the low gets more focused and better moisture. We can see with the SPC activity loop that there are a couple of watches out already, and the threat for severe weather today is increasing

This negative trend will continue through the heart of Dixie Alley on Wednesday, with tornadoes and strong winds possible through Mississippi, and again on Thursday in Alabama, Georgia and north Florida. Especially by tomorrow, the ingredients will be perfectly meshed for a potentially high end severe weather event. There is a chance to see a major tornado outbreak in the moderate risk region for severe weather outlook, which include Baton Rouge, Jackson and the parts of Dixie Alley that are far too accustomed to this kind of weather.

Forecasting for the eclipse

Cloud coverage forecast with the eclipse totality track overlaid, provided by pivotalweather.com

One thing that we know for sure about next week, is that for a long track of the eastern US, the moon will obfuscate the sun in the mid-afternoon. The eclipse is happening, and we’ve long known where the eclipse was happening.

Every forecast you see usually comes with a couple of words spared for the level of overcast on a given day. There is almost no brainpower expended on this process for most meteorologists that I know. Essentially, my go to method is to determine flow if you are near the sea, and proximity to an area of inclement weather. It works out well enough, and is frankly not something that many people follow up on.

So with that in mind, just know that I and most other weather people are flexing a muscle that we don’t often exercise when discussing the potential visibility of the celestial event of the year. I can state with some more knowledge that there will be an area of low pressure over the Upper Midwest that is quite occluded. At the time of the eclipse, the secondary low will be over the eastern Great Lakes, and the boundary will be along a line roughly from Pittsburgh to Houston.

Along that line, in particular, expect some clouds, and it will probably be a little dicey south of that boundary with moisture spilling into the region. The low over the Great Lakes, as well, will likely be more cloudy than not. Of course, this coincides with the axis of greatest coverage for the eclipse, which is a bummer for something so anticipated.

If you travel to Texas for the eclipse, you can still see some natural phenomenon in the evening. The next round of unstable weather will touch off some severe storms in west Texas, targeting the Wichita Falls area on Monday evening, with tornadoes a concern, along with large hail. I can confirm that these thunderstorms will completely obscure the sun.

March Forecaster of the Month

We’ve made it through the third month of the year that had an intense focus on the Midwest. Victoria-Weather, as should be expected, was strong for the month, but not as strong as The Weather Channel, who took the month, and the lead through three months for the year.

OutletForecast Wins (year)
The Weather Channel6.49
Victoria-Weather3.13
Clime2
WeatherNation1.83
National Weather Service1.49
Accuweather1.16
Weatherbug0.67

Weather may hamper bridge cleanup efforts this week, will improve

As seen in the video from NBC news, tragedy has befallen Baltimore Harbor, where a cargo vessel leaving the harbor lost power and steamed directly into a support for the Key Bridge, the outermost bridge spanning the Patapsco River, collapsing the span into the River. Two were rescued, though around 20 drivers and construction workers are through to be missing.

Today, this morning, while time is the most critical for whatever recovery can be done to save lives if possible, the weather was at least accommodating. There were clear skies and the Patapsco was calm, which will allow the waterway to be as clear as the waterway can get. It is a busy thoroughfare for maritime traffic and surrounded by a large city, so it is generally murky, and often quite chilly.

Even after the initial recovery is completed, it will be important to continue clearing the wreckage from the mouth of the Patapsco. Baltimore Harbor is one of the busiest on the Eastern Seaboard, and an important source of goods coming into and out of the United States. The longer the harbor is closed, the more likely it is to make a dent on the economy.

Unfortunately, the weather will not be cooperating in these efforts in the next couple of days. There are storms, both rain and snow, from the Great Lakes to the the Florida Panhandle, and this system is headed eastward. It won’t have much energy or much moisture for the coastal Plains, but it will rejuvenate upon reaching the ocean. Even before moisture falls, inflow will blow right through Chesapeake Bay up to Baltimore Harbor.

Rainfall will likely be most intense on Thursday morning, before a reconstituted system can pull off to sea. For the next couple of weeks, the mid-Atlantic looks to expect normal temperatures, but above normal moisture. The falling rain muddies up rivers, and will not help divers without the aid of sonar. Fortunately, for the long term recovery and replacement efforts, near normal conditions are expected around Baltimore, which means warming temperatures and average precipitation.

Hopefully, this can facilitate a rapid clean up and a return to normal for the city of Baltimore. Victoria-Weather extends condolences to those who have lost during this tragedy.

Severe weather is the other side to the story

I wrote last week about the strange forecast coming up for the Twin Cities, where some forecast outlets were calling for a ton of snow, despite so many factors working against a huge accumulation. Well, the storm is nearly over (a recap on that through some updates on the site later) in Minnesota, but the system is still around, and bringing some severe weather concerns in the deep south.

A strong jet flowing north-northeast to the Ozarks, sequestering a pocket of energy in the Mississippi Delta

The jet across the country is strong, a common scenario when encountering spring season storm threats, and it is helping the system in the Plains occlude fairly quickly, with an additional area of low pressure developing at the surface northwest of the Mississippi Delta. There is a copious amount of moisture down here, as always, but now also quite a bit of turning in the atmosphere, or vorticity.

The vorticity is compounded by the fact that the wind is changing directions. While the wind at 250mb, as above, is coming from the southwest, winds at different levels of the atmosphere are angled at different directions. This is called vertical shear, and is something that can help a storm build upwards quickly, and produce twisters at the surface. The area bracketed by the blue has the greatest shear, and will move east into Mississippi overnight, following the storms.

There are already some bands of storms, though none of it yet severe, moving through Louisiana, and it looks like if any storms develop, they will be embedded within a line with rain falling around it. This is a typical mode for “Dixie Alley” where storms make themselves nearly impossible to find, not only by occurring in a tree filled environment, often at night, but also by usually falling in the midst of especially rainy thunderstorm complexes.

The NWS is calling for a chance for especially large and dangerous tornadoes tonight, potentially in Jackson, Natchez or Meridien, and it is important to stay vigilant as the storms develop and move into the area. There are no basements, generally, in Mississippi, so ensure a spot in a storm shelter if storms loom.

Storms will likely continue deep into the night, but the low across the center of the country will be too stretched to allow for things to continue far into Alabama or Georgia tomorrow. Additionally, there will be a pause in the rough stretch of weather, allowing Delta residents a chance to breath and recover, if necessary. Let’s hope it isn’t.

A curious storm with a wild forecast

A pair of systems are bringing a taste of winter to the Midwest tonight and with another round coming Sunday night. The feature that has really already occurred in the Upper Midwest is a classic Clipper feature coming right out of Canada. There was a solid 2-5″ in a stripe north of the Twin Cities, and forecasts were pretty consistent on it.

A larger feature moving in this weekend from the central Rockies promises to make for more interesting weather, starting Sunday afternoon and lasting through at least Monday. But how much snow will come out of this system? That’s the big question, and there isn’t really a solid answer, but I’ll do my best to get us there.

My friends started messaging me earlier this week, exclaiming that their weather apps were calling for nearly 2 feet of snow! That seemed ridiculous, and I looked at the various weather models that I use, and ultimately, I came to the conclusion that yes, the forecast of 2 feet of snow in Minnesota was ridiculous. At the time, the feature looked like, at most, a producer of 7-10″ of snow. It now projects as a stronger storm, but 2 feet still seems pretty absurd.

It’s not that there won’t be enough moisture. It’s spring now, and there aren’t any features in the Gulf blocking moisture, but all of the things one looks for in a system that sees snow totals stack up aren’t there in the Twin Cities. Despite the snow that fell overnight last night, there is no snow on the ground for most of the region, and the ground is quite warm.

Also warm: the atmosphere. This system is going to be rising from the south and pulling some warm air northward. This will change some of the precipitation to rain, and failing that, will reduce the moisture to snow ratio. Water crystallizes as it gets colder, so the amount of liquid water it takes to get to an inch of snow becomes less and less. The snow this weekend will fall in temperatures that will be flirting with, if not exceeding, freezing.

There will be a gradual ratio through Minnesota, and some bright bands of heavier and lesser snow owing to some local effects, but not everywhere will hit over 10″. Some places sure will surely avoid the heaviest precipitation and see less accumulation, and some areas will see heavy precipitation that falls more as rain than snow. Somewhere between, there will be a stripe that gets 12+ inches of fresh, wet snow.

Now, where will that area of heaviest snow be? Let’s see the NWS’s best guess:

Well, that narrows it down. These are the most likely totals, according the NWS forecast, but I also think we should expect the low end of these ranges, especially on the north and south parts of the forecast area.

Storms ravage the Midwest

A two day severe weather marathon stretched from Kansas to Ohio with tornadoes starting near Topeka, and becoming increasingly more destructive, ultimately leaving lives turned upside down across Indiana and northwest Ohio in particular.

The system came into being in an almost textbook manner. There was a stationary boundary in the PLains that needed only be given the energy of an upper level trough to get moving. That was when the severe storms started in Wednesday, with discrete super cells cropping up in northeastern Kansas. In addition to the tornadoes around Topeka, there was very large hail seen in the Kansas City suburbs.

The system got more organized as Wednesday turned to Thursday, and the warm sector we look for in a severe weather outbreak showed up in the southern Great Lakes. Severe weather developed all the way southwest to near Dallas, with strong winds and large hail reported in many locations. It will be the tornadoes found in northeast Indiana and northwest Ohio that will be remembered, though.

Storms rotate the most near the center of an area of low pressure, as a general rule of thumb. There is enough built in vorticity that any storm specific helicity is just added to the mix, and can both make tornadoes and very large hail likely. The low tracked through the Great Lakes, and ultimately, destructive tornadoes followed.

The two areas that were most directly impacted were Winchester, Indiana, where an estimated EF-3 tornado left a swath of destruction throughout the city, and in Logan County Ohio, north of Springfield, were three people were killed by a tornado.

This is the beginning of the severe weather season, lest we forget, and we have at least three more months of the particularly busy part of the year. Fortunately, we are coming off a quiet year for severe weather, and this part of the country is having a quiet spell to recover. Let’s hope this is as bad as it gets this year, but I fear it won’t be.

Cooler air coming, but big snow not likely

The conversation I keep hearing is people being reluctant to say we are at the end of winter, because in recent years, we have seen late March and April snows. It’s been a mild winter, and many Midwestern residents can’t accept that it might just be mild all the way through.

Well, through the middle of March, we have a trend for below normal temperatures, which could certainly make some people think it is a return of winter, but significant moisture isn’t going to come with that cool down, save, perhaps, for the Great Lakes.