ALERT: Major Tornado Outbreak Expected Tomorrow From MS to OH

[FourScore]

TO THE ADMINS: I have knowingly copied this entire diary due to the importance and urgency of it's content. I know that weatherdude wishes the information to be as widespread as possible. If you still want me to edit it to the standard 3-4 paragraphs, I will gladly do so. All links within the diary (and there are several) can be found at the source: http://www.dailykos.com/story/2012/03/01/1069996/-ALERT-Major-Tornado-Outbreak-Expected-Tomorrow-In-MS-AL-TN-KY-IN-OH?via=siderec .

Thu Mar 01, 2012 at 07:07 PM PST
ALERT: Major Tornado Outbreak Expected Tomorrow From MS to OH
by weatherdude

The atmosphere is setting up for what could be described as a major tornado outbreak during the day tomorrow (Friday March 2). The current forecasts have the thunderstorms forming around noon, rapidly intensifying, and lasting into the evening and nighttime hours. The SPC has issued a moderate risk for severe weather for areas from AL/MS, a large part of Tennessee and Kentucky, as well as parts of Indiana and Ohio. There is a potential for long-track, intense tornadoes in the strongest storms that develop, as well as a damaging wind and large hail threat.

According to a Facebook post by the NWS, the SPC will likely upgrade the moderate risk to a "high risk" tomorrow -- the highest risk they issue. They only issue one or two high risks per year excluding last year. This has great potential to be a serious weather event, and it's one that needs to be taken seriously by anyone who lives in this area.

Contrary to what some local meteorologists are saying, this will NOT be as bad as the April 27, 2011 tornado outbreak. This has the possibility to be the biggest outbreak since April 27, but it will NOT be as bad as that tragic day. That was a once-in-a-generation outbreak that requires the perfect conditions in the atmosphere to occur. While all indications point to this being a potentially significant tornado outbreak, it is not analogous to the April 27th event.



A low pressure system will work its way into the Tennessee Valley through the morning and into the afternoon, which will provide sufficient lift to fire off thunderstorms in western TN and KY.

The NWS office in Nashville highlights how serious of an outbreak this is expected to be:

A BIG SEVERE WX OUTBREAK IS EXPECTED FOR MID TN FRIDAY. STRONG LONG TRACK TORNADOES...DAMAGING WINDS AND LARGE HAIL ARE ALL POSSIBLE. SPC CONTINUES TO POST A MODERATE RISK FOR SEVERE WEATHER OVER THE MID STATE. THIS EVENT LOOKS MORE WIDESPREAD AND SUBSTANTIAL THAN THE SEVERE THREAT WE HAD YESTERDAY...PROBABLY THE BIGGEST OUTBREAK OF TORNADOES SINCE APRIL 27, 2011. THIS EVENT COULD BE ONE OF THE GREATER IMPACT EVENTS IN THE PAST FEW YEARS. THE PUBLIC SHOULD BE STRONGLY ADVISED TO TAKE THIS THREAT VERY SERIOUSLY.

The severe weather parameters for tomorrow are pretty large. One of the big ones we look at for tornado development is called "helicity" -- which uses a mathematical formula to calculate the amount of rotation that can develop inside of a thunderstorm. A helicity value of about 150 is required for a supercell thunderstorm to form, with values at or above 450 required for violent (EF-4 to EF-5) tornadoes to develop.

The latest available model run (18z NAM) shows helicities between 500 and 550 across much of Tennessee and Kentucky. If current trends hold, all indications point to the possibility of significant tornadoes on the order of EF-3 or larger. I wouldn't be surprised if there's EF-4 or even EF-5 damage by sunrise on Saturday. It won't be as widespread as April 27th, but the potential for large, violent, long-track tornadoes is real.

As of right now, I believe the "bullseye" will be central TN and central KY. That could (and probably will) change as the 00z models are processed and released in the next few hours.

The SPC issues the next outlook around midnight Central Time, so we'll have a better idea of what's going on in a few hours. I'll have a more complete diary tomorrow morning, detailing who, what, when and where will get hit the worst.

Now is the time to prepare. Think about where you need to go tomorrow. If you can cancel or put it off, do that. Many school systems from AL to OH have plans to dismiss school early due to the threat of severe weather, so if you have kids, make sure you know what your local school system plans on doing tomorrow.

Pay attention to your local news. TV stations in the threat zone will likely go wall-to-wall coverage once the storms develop. Most news stations have a policy where they will start uninterrupted live coverage if a tornado warning is issued in their viewing area.

You need to start thinking about where you'll go if a tornado warning is issued. If you have a basement, go to your basement and (if possible) take shelter under the stairwell. If you don't have a basement, take shelter in an interior room like a bathroom or closet. Many people who survived the big tornadoes last year survived only because they were in an interior room.

Start gathering up your important documents (non-faked birth certificates, Social Security Cards, credit cards, loan documents, deeds and leases, etc.) and put them in an air-tight zipper bag. Keep them close so you can grab them and go to your shelter if a storm threatens.

Charge your cell phone tonight. Program an emergency telephone number into it. Make a contact in your phone or put a piece of paper in your wallet called EMERGENCY or ICE (In Case of Emergency). If something happens to you, emergency crews will see this emergency contact and call them without having to dig for information.

Wear durable clothes tomorrow. Jeans, strong shoes, socks. This sounds silly, but if you have a helmet, wear one if you go under a warning. Researchers at the University of Alabama recently found that wearing a helmet can improve your chances of survival if you're hit by a tornado. Many people die because tornado debris strikes or goes through the human head.

If a warning is issued...do not go outside and try to look for the tornado. People die because of their need to run outside and look for the tornado themselves. As soon as you hear the warning, go to your storm shelter whatever it may be. Turn up your TV and wait until they say that the tornado threat has cleared your location before assuming it's safe. Bring a battery operated radio and a flashlight with you in case your power goes out.

DO NOT RELY ON TORNADO SIRENS FOR YOUR WARNING. Many tornado siren systems are old and unreliable. Besides that, they're not designed to be heard indoors. Get a weather radio. Listen to local news. Go to the NWS online. There are a hundred other ways to get your tornado warnings, just do not rely on tornado sirens. Relying (or lack thereof) on tornado sirens was a major fatal mistake many people made in Joplin last May.

If the tornado hits your house/building, get down into the "tuck and cover" position. It's uncomfortable, but it's designed to reduce the surface area that can be hit by debris, as well as protect your head and neck from injury.

If you're out driving and you see a tornado, there are several options. Vehicular tornado safety is a very controversial subject in the meteorology community right now. Some say to try to drive away from the tornado if possible. Some say to get out of your car and lie flat in a ditch, but ditches tend to collect debris, so you might get injured or killed, then buried under debris. Your best bet is to go to a local business or NON-BOX (box stores like Walmart, Target, Home Depot are terrible places to be in a tornado) store to take shelter from the tornado. They will let you in. Whatever you do, DO NOT TAKE SHELTER UNDER AN OVERPASS. Not only can parking your car cause a traffic jam, but the confined space underneath an overpass actually speeds up the winds. Instead of taking cover, if the tornado hits you, you'll likely get sucked out and...well, you get the idea.

Get a programmable weather radio! Simply, a weather radio is a fire alarm for the weather. They save lives by sounding a loud siren the second the NWS issues a warning for your county.

I'll have another writeup tomorrow morning about this system, with rolling liveblogs throughout the day. Don't rely on my liveblogs for your warnings...they're there to let you know what's going on and to try to grab your attention to the bad weather...

SNIP

...7:59 PM PT: To those curious, here are the TOR:CON values from Dr. Greg Forbes of The Weather Channel:

Friday March 2
AL north - 5
AL central (night) - 3
AR east, north-central - 3
GA north (night) - 3
IL south - 4
IN south - 4 to 5
KY central - 7
KY west - 4
KY east - 6
LA north - 3
LA central, southeast (night) - 3
MO southeast - 3 to 4
MS north - 5
MS central (night) - 3
NC west (night) - 3
OH - 3
TN north-central - 7
TN west - 4
TN east - 5 to 6
TN south-central - 5
WV west - 4
Other areas - less than 2

8:46 PM PT: Please ignore Inaccuweather's blatant attempt at fearmongering by insinuating that this system will be the 1974 Super Outbreak all over again. It won't be. "Accu"weather is in the business of sensationalism and profit.

[Art_from_Ark]

1. March is certainly coming in like a lion, isn't it?

I hope everyone stays safe.

[BadgerKid]

2. Central KY and north-central TN have risk "high".

[DCKit]

3. weatherdude knows his shit.

That article was an education.