Remember if you are close enough to hear thunder you are in danger of being struck by lightning.   Here is a fun (But be safe…while indoors of course!) way to estimate how far away a lightning strike is:

“Flash to Bang”

You can estimate the distance to a thunderstorm using the “Flash to Bang” (time from seeing lightning until your hear thunder) by counting the seconds between the lightning “flash” and the “bang” of thunder. Each five seconds equals one mile. If you count 15 seconds, the flash was 3 miles away and you know that you are in a high danger zone. Six miles is still in the high danger zone.

These remnants of what had been Tropical Storm Lee, including flash floods, tornadoes and non-stop rain have authorities reacting with a real sense of urgency. The Wall Street Journal is reporting that at least 7 people have lost their lives due to flooding related incidents and over 100,000 residents of PA, NY, MD have been evacuated. Families staying in shelters and away from their permanent residences are expected to stay away from their homes until Sunday at the earliest.

While showers still brew up and down the affected region, authorities say it will be a while before they can really survey the damage done that included a partial bridge collapse in northern Pennsylvania, vehicles and other property swept away, and failed sewage treatment plants.

The mayor of Binghamton, N.Y., said the severe Susquehanna River flooding was the worst in more than 60 years.

Forecast Discussion: (Because you asked…)

Potent upper level shortwave and eventual closed low will work into the Great Lakes region sweeping a cold front across the area late tonight.  An increase in the 500 mb winds (~50kts) will provide ample shear for severe thunderstorms and isolated supercell storms.  Convection will be aided by moist and unstable atmosphere that will provide CAPE values (a common measure of instability) in excess of 4,000 j/kg.  This highly unstable atmosphere set off by an advancing cold front and moderate shear will likely allow for the formation of an MCS (Mesoscale Convective System) possibly in the form of discrete supercells initially followed by a squall line across most, if not all of our area.   

The timing on the storm will be after 5 PM, as a cap in the atmosphere is expected to hold until then.  Initial supercell thunderstorms would be the most likely culprit of an isolated tornado with the evolution of this event focusing more on damaging winds and large hail as the evening progresses.   Stay tuned for details!

For most people, the question was — What is a waterspout?

Waterspouts are similar to tornadoes in their funnel shape and general behavior, but they may not be what they seem. 

First, water is not being pulled up from the surface of the lake. The funnel you see is a visible weak rotating column of air surrounded by condensation being created by an influx of warm air.

Second, they typically form overwater, beneath a cumulus cloud, but the circumstances for development can vary in each sittuation.

Third, the intensity and potential danger of each waterspout is different. In today’s case, waterspouts were a big concern to boaters and marine life, but once these particular storms hit land, they fell apart. It takes a pretty strong storm and lots of warm air to support a waterspout onland for very long.

All in all, it’s just a really amazing weather feature to admire — just don’t get too close!

Thankfully no reports of significant tornadoes, but the aftermath of the thunderstorms and heavy rains have now elevated the flooding concern for many areas. Here is doppler radar estimated rainfall totals of 2-4″ or more across most of the area:

Two rivers in particular could see Moderate/Major flooding. The Blanchard River may crest just below 13.0′ early Friday morning which is the mark for major flooding:

The Maumee river at Defiance, Waterville and Grand Rapids are expected to see Moderate flooding. Grand Rapids may see the worst, cresting at 18.5′ which is 3.5′ above flood stage. If this stage is reached, it would equal the 100 year flood level impacting several of the buildings in the downtown area.

Other cities and rivers expected to see some degree of flooding:

CLICK HERE for River levels east of I-75

CHICK HERE for river levels west of I-75

CLICK HERE for river levels in Michigan

Radar Image at time of tornado:

Storm Relative Velocity a time of tornado:

For complete information on this tornado and the storm survey CLICK HERE.

You can see the pictures here:  http://www.nasa.gov/topics/earth/features/harvest_tornado.html

Updates are being posted on www.wtol.com/weather and www.facebook.com/mikestonewtol

Our StormTrack 11 doppler estimates that a few spots received between 3 and 6 inches of rain.  You can see in the snapshot below, a bulls-eye of orange stretches across eastern Allen and western Hardin county, where isolated 6″+ amounts occurred.

This heavy rainfall was the result of something called “training”.  It is when waves of thunderstorms move over the same area repeatedly — like train cars on a track passing the same area over and over.  Many flash flood events occur from this phenomenon.

Flooding causes the most severe weather deaths, and many of those deaths result in people staying in their cars.  The National Weather Service has a flood safety slogan called “Turn Around, Don’t Drown”.  Flood water can sometimes wash away a road, so the water may be a lot deeper than you think.  About one foot of water can make about 1,500 pounds buoyant, so a couple feet of water will float most cars.

Flood deaths also are a result from people in a low-lying area, like a bridge underpass, that gets inundated with water in a short period of time.  The bottom line is, when very heavy rain occurs, being in a car is not a very safe place to be.

312 Tornadoes reported from April 27-28. This far surpasses one of the worst tornado outbreaks historically, the super tornado outbreak of 1974 on April 3-4 where 148 tornadoes were reported across 13 states.

April 27th was the deadliest single day for tornadoes since March 18, 1925 when 747 people were killed during a tornado outbreak. (Tri-State tornado)

The monthly record for April tornadoes was 267 in 1974. This past April recorded over 600 tornadoes! The previous record for any month was 542 tornadoes in May of 2003.

Click Here For the Full NOAA Report