Tonight
Showers should develop and scatter across middle TN. There’s a small chance we will see one or two. Fog develops overnight and lasts into this morning. If you were foggy this morning, it’s likely you’ll be foggy Wednesday morning.
PM T’Storms Possible This Week; Rain Friday; Wet Steeplechase
Today – High of 71
Very light, scattered showers or a thunderstorm possible today. Odds of one getting you are pretty low, but if it’s going to happen, the HRRR thinks 6pm is the most likely time:
Wednesday – High of 78
Like today, the odds of rain are small. If it’s going to rain, early evening is the most likely time. Here’s the Hi-Res NAM showing Wednesday night at 7pm:
Thursday, Friday & Steeplechaseday
Thursday – High 82
Much like today and Wednesday — chance of rain or a thunderstorm, most likely in the late afternoon/evening hours.
Friday – High 77
Thunderstorms are likely Friday into Friday night. Our NWS was talking about it this morning:
MODELS CONTINUE TO PROMOTE THE ARRIVAL OF A PRETTY DECENT COLD FRONT . . . SLICING ACROSS THE MID-STATE FRIDAY NIGHT INTO SATURDAY AND USHERING IN A PERIOD OF RATHER COOL TEMPERATURES FOR SUNDAY AND MONDAY.
Iroquois Steeplechase: Wet Friday, Dry Saturday (at least for now)
I’ve had about 50 people ask: “What about Steeplechase?” Approximately 100% of them are women, all wondering what to wear.
Before we dive in, a disclaimer: I’m about to show weather models for Friday & Saturday. Weather models are never the Gospel Truth, and are certainly not to be relied upon 5 days away. They are a decent indication of what might happen.
Afternoon Crazy Ivans (Rain) + Rest of the Week + Steeplechase Update
Today
Although the morning rain moved out, models redevelop showers to our east this afternoon and early evening, and spin them in here. These isolated/scattered showers are approaching in an usual direction: east-to-west. We call these “Crazy Ivans,” a reference to The Hunt for Red October (where a Russian nuclear submarine – from the east – almost started a war by defecting to the west). If you don’t get it, relax, you’re better off for it (for those who’ve seen the movie or read the book, we know it’s also not a technically accurate phrase). It’s nerd humor.
Sit & Spin Rain Monday; Premature Steeplechase Forecast
Monday
The weather version of the
is a low pressure center. A few important differences between the Sit-n-Spin and a low pressure sit and spin include:
- The Sit-n-Spin rotates clockwise and counterclockwise. A weather sit and spin only rotates counterclockwise.
- The Sit-n-Spin rotates small children. A weather sit and spin rotates clouds and rain.
Similarities:
- Both may induce vomiting.
- Both can sit – for days – in one place without being picked up, until someone/someOne decides to pick them and place them where they belong (the toy closet or garage; Atlantic Ocean).
- A mature, tropical sit and spin / low pressure system can become a hurricane which generates winds up to 200+ mph. My childhood friend Frankie Vanderburg could accomplish a similar feat. He could sit on that thing and generate centrifugal force sufficient to vaporize Star Wars figures (or at least warp them into the bushes). Fathers attempting to stop Frankie by stepping on that thing risked a torn meniscus or severed cruciate ligament. Their strategy was to wait him out until the bearings in the sit-n-spin vaporized, or he tired himself out. I don’t know what came of Frankie, but $5 says he’s piloting fighter jets somewhere.
For the last several days, this particular low pressure center has been cut off from the winds which would push it into the Atlantic Ocean. Yesterday it was around Memphis. Today it crawled to E MS and N AL, which is around where all the models think it’ll be tomorrow as it drifts further east and spins light rain showers into middle Tennessee. Here’s the NAM model, which is a fair representation of the rest of the models:
The Fifth Day of May
Today
Happy Cinco de Mayo everyone!
We are sitting pretty right now, between the core of low pressure and the bands of rain wrapping around the system. Keeping us dry for now…
Infrared Satellite Imagery (yellow and blue high cold cloud tops usually rain):
Saturday Night Showers. Light Rain Sunday (ETA ~ 4pm).
This afternoon we thought the rain — which moved east — was going to stay east. It hasn’t.
At 7:27pm, light rain showers crept northwest across both counties:
Why is this happening? This satellite image (from 7:15pm) explains:
Dramatic Improvement: Dry Afternoon + (Maybe) Sun
April postcards from Old Man Winter are common, but this May postcard has been waaaay out of bounds.
That said, you’ll like what we have to say about the rest of the day.
Today
At 11am the rain rope (“rain shield”) was sitting along I-65 and very, very slowly moving east at around 15 mph. It’s also way too chilly for May: 46 at 11am.
Updated Weekend Outlook: Wet, Dreary, & Cold. Indoor Sports Advised.
Flood Watch
A Flood Watch is in effect until 7 am Sunday. Here’s an official graphic:
Tonight
It’s going to rain tonight and into the overnight hours. The ETA for Williamson, then Davidson, Counties is between 8pm and 9pm tonight. Follow along on Twitter for more frequent and detailed updates (@NashSevereWx).
Who’s Doing the Rain Dance? Flood Watch In Effect. Weekend Wash-Out.
The Setup
Whoever is doing the rain dance, did it right! Blame a “cutoff low” spinning in the middle of the country. It should rain out most – if not all – of the entire weekend.
So what is a cutoff low? It’s a low pressure system that has been “cutoff” from the flow of the jet stream (upper level winds) which push weather systems around. Since the low pressure system is cutoff from what steers it, it will just meander over the next few days, sending waves of rain our way. Until another system comes along and shoves it into the Atlantic Ocean, we are stuck dealing with it.