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More unsettled weather

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Main Threats

Today and Wednesday: Heavy downpours that could lead to localized flash flooding.

Summary

Our soggy, wet pattern continues, with more showers and storms today, tonight, and Wednesday. Keep that umbrella handy! We could easily see another couple inches of rain, and some spots will likely see even more than that. Therefore, it is important that you drive with care and be aware that localized flooding and flash flooding is a real possibility over the next 48 hours.

Below is a map of estimated rainfall that has fallen from Friday to last night. The map is a bit off, because I’ve had over 5 inches of rain at my house in northern Cumberland County.

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We will also be a bit mindful of any storm that develops today. They will be capable of becoming strong, with gusty winds and torrential rainfall. Keep in mind that shallow-rooted trees in saturated soils don’t need much of a push from the wind to come toppling down.

The front pushes through here tomorrow and the Storm Prediction Center has included everyone north of I-40 in the marginal risk for severe storms. The marginal risk is the lowest of the five severe weather categories. Never the less, as I mentioned above, saturated soils and shallow-rooted trees don’t mix well.

After the front clears our area, drier air will begin working in. That will limit moisture for an upper-level disturbance that will swing through here on Thursday, but there will still be enough moisture for isolated to scattered showers.

By Friday and Saturday, drier air has really begun to filter into our area, but with the front stalling out so close to our south, we can’t completely rule out an isolated afternoon/evening shower either day. Most of us will stay dry. The greater rain chances (and those aren’t that great) will be found south of I-40.

Discussion

Yesterday evening, I had to tell you about a tornado warning in Dekalb County, which is located just west of White County (Sparta). The storm developed some rotation and briefly looked capable of producing a weak tornado. What was most concerning was that the storm was headed in the general direction of Cookeville. Thankfully, that rotation was brief and the storm turned more northward, taking it west of Cookeville. A flash flood warning was then issued, as radar estimated up to 4″ of rain had fallen from the severe t-storm.

We had just enough spin in our atmosphere to cause an isolated situation like this one. Had we not been cloudy and rain all day, we could have had more storms like this one. As you’ll see in the Records section below, we had a very similar situation to this set up in Cumberland County back in 1977.

Tropics

The tropics remain active this morning and there’s really no end in sight. This season is proving to be an active one, although it had a bit of a late start. The closest concern is the disturbance east of the Carolinas. That system has a 50% chance of developing into a storm. Thankfully, the system is not expected to make landfall in the U.S., though it will likely bring rainfall, gusty winds, and dangerous surf conditions to the coastal areas of the Carolinas. That is the last thing they need but what can you do?

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We are also still watching the remnants of Kirk in the southern Atlantic. He’s one to keep an eye on as he makes his way toward the Caribbean. As of now, there are no big concerns for him, but he’s definitely on the National Hurricane Center’s radar.

Then, there’s the remnants of Leslie (red-shaded area). That system is expected to also redevelop, but it will stay well out to sea and be no threat to land.

Records

Today’s record is interesting. We rarely get September tornadoes on the plateau but on this day in 1977 we learned that September tornadoes are not impossible around here. Heck, we nearly learned that lesson over in Dekalb County last evening!

At approximately 2:00 that September afternoon, a weak tornado touched down just east of Highway 127, just before you get to the Highway 68/127 split in Homestead. The storm responsible for this tornado had passed over Cumberland Mountain State Park.

The tornado touched down in the Dorton area, uprooting trees and damaging roofs and exterior walls of homes and some buildings. In the Byrds creek area at least 75 trees were uprooted at the Rowell’s apple orchard (perhaps the trees were heavy with apples?). The tornado traveled northeast, downing more trees as it crossed Highway 70. The tornado then crossed Interstate 40 and lifted just shy of entering Fairfield Glade. The tornado was on the ground for three miles and was rated F-1. Estimated winds were around 75-95 mph.

Below are the track maps for the tornado, with the bottom one zoomed in for a closer look.

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Two years later Cumberland County would be devastated by a much more powerful tornado that would accompany the super outbreak of 1974. Every county on the plateau would see damage in that super outbreak, the likes of which they had never seen before. More on that when we get to April….

And now for an odd record…..

Hurricanes practically never come ashore on the West Coast. The water is a bit too cool for hurricanes and the trade winds often sweep those storms toward the west, out over the open Pacific. But, on September 25, 1939 a very rare thing happened; a West Coast hurricane!

The storm moved ashore near Los Angeles and brought historical rainfall amounts. Nearly 5.5 inches of rain soaked the city within 24 hours. The storm was referred to as El Cordonazo, which is a term normally given to hurricane winds that affect the west coast of Mexico. Keep in mind that this was 1939 and we hadn’t started naming storms yet.

This storm produced record rainfall for the month of September for southern California. The greatest loss of life was to 45 individuals who were killed out at sea.

News

I know some of you may be wondering when a more substantial fall-like air mass will arrive. Temps for this coming weekend just keep warming up, though we will still be much cooler and drier than we have been. The good news (for you fall weather lovers) is that the extended outlooks continue to show cooler weather for October. Fingers crossed, right?

Below is a map of temps for the 6th-19th of October.

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You all have a great day and try to stay dry!

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