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Devin Bowling took this shot (in Albertville, Al.) of a wall cloud (upper left). A tail cloud is the center, pointing toward the rain. Tail clouds are often mistaken for tornadoes.

As forecasters expected, violent storms tracked across Alabama and Tennessee on Tuesday. Tornadoes then hit South Carolina in the early morning hours of Wednesday. I was on air for nearly 8 hours straight. My voice is yet to recover.

Wall clouds are the parent clouds of a tornado. Not every wall cloud will produce a twister but if you see one, go the other way. Fast. Better yet, get under something sturdy. DO NOT head for a nearby overpass. Winds are accelerated under them and taking shelter under one can be a deadly mistake.

On the Great Lakes, it was the second strongest storm on record. Winds gusted to 80 mph. The waves on Lake Superior reached 9 meters!! (For the metrically challenged that’s over 26 feet!!)

The pressure at the center of the storm dropped to 955.2 millibars. That’s the lowest pressure ever recorded in Minnesota. Only the storm of January 1978 was stronger.

The 1978 storm is referred to as the great Ohio Blizzard. The pressure dropped to an incredible 950 millibars in that storm. Almost everyone older than 35 in Ohio can tell you stories of that event.

The Great Lakes Storm on Tuesday. It passed over Duluth and now holds the record for the lowest pressure ever recorded in Minnesota. Image courtesy NWS Duluth.

The storm in 5th place is rather famous. On November 10, 1975, (thirty-five years ago next month) a surprise storm produced a low pressure of 980 millibars. That storm hit Lake Superior hard and resulted in the sinking of an iron ore carrier called the Edmund Fitzgerald.

Canadian Gordon Lightfoot made the gale famous by his song about the doomed freighter. One line in particular has stayed with me.

“Does anyone know where the love of God goes, when the waves turn the minutes to hours.”

Update Oct. 29,2010: It now appears that the Minnesota storm missed the the non tropical storm record for the mainland U.S. by 0.01 inches of mercury!

Numerical weather prediction model forecast valid at 8 PM U.S. East Coast time Tuesday. This storm will spread tornadoes across the U.S. Midwest and near hurricane force winds on the Great Lakes.

When most folks think of tornadoes they imagine a warm spring afternoon suddenly turning stormy. More often than not this is true but there are glaring exceptions. Last night was one and Tuesday will be another.

A powerful storm system has been winding up  in the Plains. Last night a band of storms from Texas to Alabama brought tornadoes and large hail. Here in North Alabama, I was up for much of the night watching radar.

Winds going toward the radar right next to winds going away from the radar. This is what a tornado looks like on a Doppler radar. Image from Penn. State NEXRAD Archive. Click for larger version.

Large super-cell tornadoes are the easiest to spot and we had only one of those up in Tennessee. The ones you have to really watch for are the smaller more short lived twisters that are embedded in a squall line.

Around 4 AM CDT Monday morning, the Doppler radars indicated a strong circulation in the line over NE Alabama. The little town of Ider, near Fort Payne, was struck with a twister around 4:15.

The tornado looks to be an EF-1 or perhaps briefly an EF-2. An EF-1 tornado has winds of 32-50 meters per second (73-113 mph). That’s the equivalent of up to a category two hurricane on the Saffir-Simpson scale.

The Storm Prediction Center  (SPC) in Norman Oklahoma issues the tornado watches for all of the U.S. They’ve notified Meteorologists like myself and at the local NWS forecast offices that they believe there is a rare “high risk” of tornadoes over Indiana and Ohio on Tuesday. A high risk is rare anytime.

It’s exceedingly rare in autumn.

SPC does only one thing. Forecast severe weather. Meteorologists like myself give high credibility to their forecasts.

The Enhanced Fujita Scale- courtesy of the Storm Prediction Center (NOAA)

There’s been  an amazing technological revolution in forecasting over the last 30 years. In the 1970’s most tornado watches had no reports of tornadoes. Now it is rare for a watch not to verify.

When I was an undergrad meteorology student, I worked on a project at Okla. University in 1980 called SESAME. That stands for Severe Environmental Storms and Mesoscale Experiment. It was a fancy name for trying to correlate what severe storms were doing with what the new Doppler radars were indicating.

I remember being laughed at by people who called it a waste of money. It was anything but.

Doppler radars cover most of the nation now and make it possible for forecasters to give incredibly accurate warnings. An accuaracy I could not have imagined back in 1980.

At 4:15am Monday, the Doppler radar here in North Alabama showed a srong rotation and a tornado warning was issued. We had it on the air in less than 15 seconds from the time the NWS pushed the button. Unfortunately, most people in the little town of Ider were asleep.

The ones who has NOAA weather radios were awake because a loud alarm had gone off. If you live in area where severe weather is likely, you should have one. They only cost about 30$.

It might save your life one night.

You cannot imagine how frustrating it is to break into programming and give a warning while knowing that most people are asleep and will never hear it.

Until it’s too late that is.

Be safe,


Amazing satellite image from Monday showing smoke covering much of Western Russia. NASA/Modis image. Click for higher resolution. Fires denoted by red dots.

The death toll from the heat and smoke in Moscow is climbing rapidly. BBC Radio reported today that the death rate in Moscow is running 2-5 times normal.

This is not an ordinary heat wave. It’s actually almost unbelievable meteorologically. It’s not unusual to set a record high. It’s very rare to set an all time high temperature, but it happens from time to time in extreme situations.

What IS nearly unheard of is setting a new all time record high, then tying or breaking it 5 times in the same month! Imagine setting a record high and breaking the old record by 19 degrees F.! That’s what Moscow did on Monday 9 August. The old record was 90 in 2001. Monday Moscow hit 99F and that ties the warmest temp. Ever recorded there.

This has been going on since July as well. This kind of heat in a city where almost no one has or needs air conditioning.


The heat and dry weather has caused the swampy land full of peat bogs around Moscow to dry out and they are now burning. The smoke they are producing has reduced the visibility in Red Square to about 1 km. On Saturday, the Carbon Monoxide levels reached 5 times the unhealthful level.


There are some strong indications that a cool front will bring at least some temporary relief to NW Russia in about 5-7 days. Unfortunately, several thousand people will not likely live to see it.

Temperature anomalies in July over Eastern Europe. The heat has gotten worse since then...


Meteorologist Jeff Masters has a very good writeup about the heat in Russia here. There are some amazing pics from Russia courtesy of the Boston Globe as well.


You have to be very careful in blaming any one weather event on climate change. That said, the warming over the last 50 years has been much greater in the higher latitudes. Dr. Michael Tobis at the Univ. of Texas in Austin makes a decent case for calling this event at least VERY suspicious as far as climate is concerned.


Smoke covers the Canadian Prairies Saturday. NASA Aqua Satellite image. Click for super high HD resolution.

Smoke from forest fires in Western Canada has spread across much of the Canadian Prairies and well south into the U.S. British Columbia is tracking over 400 forest fires and other fires are reported in Alberta.

Smoke across the midwest USA. Image from Ray Hoff's U.S. Air Quality blog. Click to see more data.

The smoke is not only visible on satellite images across Canada but it has reached as far south as Kentucky. The smoke has pushed up air quality indexes across much of the Midwest. Those with asthma and other breathing disorders are being urged to avoid outdoor activity.


Across the Southern USA the weather story is the intense heat. Here in Huntsville we have had no rain in August in most areas. Another week of temperatures above 35C (95F) is on the way. Most areas will stay about 10 degrees above normal for August this week.

In Europe it is just the opposite. The heat and the smoke are in the North! Moscow continues to suffer though it’s hottest weather ever recorded along with thick smoke from forest fires. The smoke and smog in Moscow is so bad that it is downright dangerous to breathe!


Something to think about. Here in the southeast USA, this kind of summer is expected to become the normal by the end of the century.


Duck and cover! The new U.S. Record hailstone. Image from the NWS Aberdeen SD/NOAA.

If you are a weather nut there are certain records that you know off the top of your head. No need to look them up. So I knew the record books listed the largest hailstone ever measured as the one from Coffeyville, Kansas that fell in 1970. That stone weighed in at a whopping 757 grams  (That’s 1.67 pounds for you metrically challenged folks).

Nancy Knight (Top expert on hailstones) of the National Centers For Atmospheric Research holds the previous record holder, the Coffeyville KS hailstone. Diameter 14.4 cm.

Then came the severe thunderstorm that hit Vivian, South Dakota on 23 July, 2010. Les Scott saw his yard covered with HUGE hailstones and saved the biggest he could find. A power outage caused it to melt a bit but he thought it might be a good idea to let the local NWS office know about it.

They of course were very interested and came out and measured and weighed it. The Warning Coordination Meteorologist for the Aberdeen, SD  NWS then contacted the NOAA Climate Extremes Committee. They have declared that the long standing Coffeyville Kansas ice chunk from the sky is no longer number one!

The official weight of the Vivian hailstone was recorded at 879 grams or 1.93 pounds! That’s a new record! The stone also broke the record diameter of a hailstone. The previous record was 7 inches from a stone that fell in Aurora, Nebraska in 2003.

Current CO2 Level in the Atmosphere