All EF-5 and F-5 tornadoes since 1950, labelled in order of occurrence. Courtesy the SPC.

Has Indiana experienced an EF-5 or F-5 tornado since 1950?  Yes, it was April 3, 1974 at Daisy Hill Indiana.  Does this mean that the WANE viewing area will never see a tornado of that magnitude ever?  No.  Take a look at the map above.  This map is plotting all EF 5 and F 5 tornadoes since 1950, in order of occurrence.  If you look closely, you can see to our north, Michigan has had two destructive tornadoes of that magnitude since 1950.

In the map above, I have highlighted the areas that have had the highest frequency of EF 5 and F 5 tornadoes since 1950.   There seem to be 3 areas:  Northern Alabama, Northern Iowa, and Central Oklahoma.

So, why do these areas have a higher concentration of the high end tornadoes?  There are actually two major areas:  Dixie Alley (Alabama and Mississippi) and Tornado Alley (from Oklahoma to Iowa.)   These two major areas are where very high spring humidity can connect with very strong spring jet streams.  Most times, this occurs in Tornado Alley, but some years, the jetstream is more active over the deep Southeast, possibly a function of La Nina and El Nino.

So, where does that leave us here in Indiana?

All tornadoes from 1980 to 2010, courtesy IWX NWS.

The map above is a plot of all tornadoes since 1980 in the WANE viewing area, courtesy the National Weather Service of North Webster.  Notice the the majority of our tornadoes are the smaller EF-0 and EF-1 tornadoes, but we have had two EF-4 tornadoes, both in Van Wert County.

Now I hate to come off like a fear monger, but I honesty feel it is only a matter of time that a significant tornado will move through Northern Indiana.  It may not happen this year, or in the next 5 years, but I would expect a significant tornado, somewhere on this map, in the next 10 years.

Storm Prediction Center Day 1 outlook for severe storms. (NOAA)

There is still a possibility for some severe weather associated with this slow moving area of low pressure moving through. There is increased lift across the area. However, there has not been a lot of sunshine so this area may be shifting to our east a little and western and central Ohio may be the firing grounds for some strong thunderstorms this afternoon. We are not going to rule out a few strong thunderstorms and some gusty winds across northern Indiana this afternoon though.

Radar image of Moore tornado at it’s strongest.

Above is the Doppler radar image of the Moore tornado at it’s strongest.   This is the classic “hook echo” signature with a “debris ball.”   Doppler radar works because the rain in the storm reflects energy back to the radar.  When a tornado is strong enough and hits structures, the debris is picked up by the tornado, and the lumber, shingles and insulation shows up on radar as a bright ball and the end of the hook.  If you ever see me show this live on tv for a tornado warning, you know it’s the real deal.

Summary of Moore Tornado

The final storm assessment is not complete, but as of now, the Moore tornado is rated a an EF-5 tornado with winds up to 210 mph, and at times, it was 1.3 miles wide, on the ground for 17 miles.   The NWS issued the first warning for this storm, 16 minutes before the first touchdown at 2:45 pm.   By the time it hit Moore at it’s strongest, there had been 45 minutes of warning.

The chances of a community being struck several times by an EF4 or EF5 tornado within 15 years are exceptionally low. You’ve all seen the pictures of the destruction from May 20, 2013′s tornado, but what were the details. The damage survey is releasing new information. This information is from the National Weather Service in Norman, OK. I will BOLD some of the key points.

THE NATIONAL WEATHER SERVICE DISPATCHED FOUR DAMAGE SURVEY TEAMS TO
THE PATH OF THE NEWCASTLE/MOORE OK TORNADO. NEW STATEMENTS WILL BE
ISSUED THROUGHOUT THE DAY AS THESE TEAMS REPORT FINDINGS. THIS
INFORMATION REMAINS PRELIMINARY AND THE INFORMATION HERE COULD
CHANGE.

.NEWCASTLE/MOORE TORNADO

RATING: EF5  
ESTIMATED PEAK WIND: 200-210 MPH  
PATH LENGTH /STATUTE/: 17 MILES  
PATH WIDTH /MAXIMUM/: 1.3 MILES  
FATALITIES: N/A
INJURIES: N/A

START DATE: MAY 20 2013
START TIME: 2:45 PM CDT
START LOCATION: 4.4 W NEWCASTLE /GRADY COUNTY /OK
START LAT/LON: 35.2580 / -97.6775

END DATE: MAY 20 2013
END TIME: 3:35 PM CDT
END LOCATION: 4.8 E OF MOORE OK /CLEVELAND COUNTY /OK
END LAT/LON: 35.3409 / -97.4007

SURVEY SUMMARY: EXPERTS SURVEYING IN MOORE HAVE DETERMINED DAMAGE IS
EF5 WITH MAXIMUM WINDS OVER 200 MPH. FOUR SURVEY TEAMS CONTINUE TO
INSPECT DAMAGE FROM THIS LONG TRACK TORNADO. INITIAL DAMAGE WAS
FOUND AROUND 4.4 MILES WEST OF NEWCASTLE…SOUTH OF TECUMSEH ROAD
ALSO KNOWN AS NW 16TH STREET AND EAST LAKE ROAD. THE TORNADO TRACKED
NE TO THE INTERSTATE 44 BRIDGE OVER THE CANADIAN RIVER AND THEN TOOK
A MORE EASTWARD TRACK THROUGH MOORE. TORNADO DAMAGE ABRUPTLY ENDS
0.3 MILES EAST OF AIR DEPOT ROAD AND N OF SE 134TH ST.

INITIALLY PRODUCING EF0 AND EF1 DAMAGE THE STORM INTENSIFIED VERY
RAPIDLY IN 4 MILES OR AROUND 10 MINUTES PRODUCING EF4 DAMAGE BEFORE
REACHING INTERSTATE 44. NUMEROUS INDICATIONS OF EF4 DAMAGE WITH SOME
AREAS NOW DETERMINED AT EF5 DAMAGE…THE HIGHEST CATEGORY ON THE EF
SCALE…WITH OVER 200 MPH WINDS.

ADDITIONAL INFORMATION SUCH AS MAXIMUM PATH WIDTH WILL BE UPDATED
AS THE TEAMS COMPLETE THEIR SURVEYS.

According to Norman, OK’s NWS, the following tornadoes (not including yesterday’s) have affected Moore, OK in the past 15 years. 4 out of 5 have been either EF4 of EF5.

• The October 4, 1998 Tornado Outbreak Twenty-eight tornadoes occurred in central and eastern Oklahoma, including an F2 tornado which damaged parts of Moore. It was the largest autumnal outbreak of tornadoes ever recorded in Oklahoma.
• The May 3, 1999 Tornado Outbreak This outbreak included nearly 60 tornadoes in central Oklahoma. It was the largest tornado outbreak ever recorded in Oklahoma. The first F5 tornado ever to hit a the Oklahoma City metro area killed 36 people and tore through parts of Newcastle, south OKC and Moore, OK. The damage total was estimated at $1 billion. Two F4 tornadoes also ravaged parts of Kingfisher and Logan counties.
• Oklahoma City Area Tornadoes of May 8, 2003 The central United States experienced a record-breaking week of tornadoes from May 4 through May 10, 2003, when nearly 400 tornadoes occurred in 19 states and caused 42 deaths during the seven days. Included in this total were the tornadoes which hit the southern Oklahoma City metropolitan area on May 8, 2003 including an F4 tornado which tore through parts of Moore, Oklahoma City and Choctaw.
• The May 10, 2010 Tornado Outbreak This outbreak produced 35 tornadoes in the NWS Norman forecast area alone, and a total of 55 tornadoes in Oklahoma. Two EF4 tornadoes struck the Oklahoma City metro area including Moore, killing 3 people and injuring over 80 others.

If you visit this NOAA website, click on the video and  you can see a time lapse of the satellite imagery over Oklahoma yesterday. You can see the dangerous, tornadic supercells explode in the afternoon.

 If you look at a blog post below, Chief Meteorologist Jonathan Conder has linked how you can help and donate. Destruction of this magnitude is incredibly difficult to recover from, and the people of Moore need your help.

Dry Line Thunderstorms

So how did it happen? First off we need to tell you about some facts about these kind of tornadoes. First and foremost this is a very rare tornado. It does not happen every year. Yes, we have seen tornadoes like this int he recent past, but these type of tornadoes which have 200 mile per hour plus winds only account for about 2 percent of all tornadoes. Conversely, these what we term “devastating” tornadoes account for most of the deaths. Quite honestly unless you were underground as this tornado passed there was a very low chance for survival.

Let’s talk about the dynamics of this particular storm, the set up. First off there is a weather phenomena that occurs across this particular part of the country called ‘dry line’ thunderstorms. One side of this line is filled with heavy dry air and the other side has Gulf laden humid air. The line between these two air masses or the “dry line” is a focusing point for thunderstorms as it can cause rapid instability and lifting of humid air to form clouds and thunderstorms.

Tornado set up

The second part of this set up are two very important factors which probably take it from a smaller tornado set up to a much larger one. The first feature is the low pressure which is closed or cut off from the main flow of the jet stream. This creates that counter clockwise circulation and causes the clouds around it to circulate that way as well. The last part of the equation is the jet stream. It causes what we term divergent winds which only increase the buoyancy or instability making the area  a very volatile one.

These factors combined to form the huge and deadly Supercell tornado which caused mass destruction across the area. This particular cell did regenerate across other areas but fortunately they were much less populated. What also made this storm most devastating is that it stayed on the ground and produced the strongest winds across a densely populated area.

I am just going to cut the brass tax here folks.   If you want to help with the relief effort in Moore Oklahoma, donate to the American Red Cross.   It’s this easy:  Just dial 1-800-REDCROSS or text REDCROSS to 90999 to make a $10 donation.  Click here for more information.

If you just received a text alert, or maybe your weather radio went off, you are probably wondering what’s going on.   First off, a t-storm watch has been issued until 5AM for the counties highlighted in pink in the map above.  This watch was issued because there is a line of storms moving out of Illinois into northwestern Indiana.  (Remember, you can track the storms here with our interactive radar.)  The main concern is going to be damaging winds up to 60 mph.

Severe weather risk for Tuesday

After this line of storms moves through early Tuesday morning (between 2-5AM) look for another round of storms into Tuesday afternoon.  If there is enough heating between the morning storms and the second round that is possible into the afternoon, we may see another round of severe storms.   As of now, the main risk will also be damaging winds up to 65 mph, but there is a low tornado risk also.  Stay tuned for more weather information.

Moore Tornado damage path courtesy the NWS of Norman Oklahoma.

I usually don’t get too emotional about weather coverage, but having lived in OKC, worked in OKC and married and OKC native, my heart goes out for the families of Moore Oklahoma.

Do me a favor after you are done reading this blog post.  Go to your wife, you husband, your son, your daughter, give them a hug and let them know how much you love them.

After you do that, take a moment and say a prayer for the families of Moore.  I don’t want to go into all the details here, but as I type this blog post and watch live coverage there, there was obviously going to be a significant loss of life.

Now that you have done that, ask yourself if your family has a severe weather plan.  Where will you go if a tornado warning is issued?   To your basement?  What happens if you don’t have one?  Maybe the most internal room of your house, in a bathroom without windows, or under a stair chase?  Do you have a weather radio?  Have you signed up for WANE text alerts?

We don’t see many tornadoes here, but we know we can have big ones.  Now is the time to get prepared.

Safe Boating Week (NOAA)

Weather seems like the last thing you need to check when you head out on a nice sunny day. But, I can tell you as an experience boater that a thunderstorm can change that outlook in a hurry. It can also put you in danger pretty quickly. The National Weather Service has several sites for you to check on. You may even want to consider purchasing a portable NOAA Weather Radio . These are also on sale on Walgreens with the desk top models. Also check out the safe boating link for Indiana.