Amateur radio operators are very familiar with atmospheric ducting or “skip” as we call it, which (with the help of the ionosphere when the sun is cooperative) enables some very long distance radio communications well beyond line of sight. The same sometimes holds true for loud audio, such as thunder or sonic booms. See my descriptive graphic below the “continue reading” line.
TheTempestSpark writes in Tips and Notes:
Is this “ducting”?? the Tallahassee National Weather Service office addressed it in a special statement.
“We had a lot of calls early Wednesday evening, primarily from the area from Woodville to Crawfordville, about rumbling sounds that sounded like a freight train, with residents fearing it was a tornado. But, it was NOT. The leading edge of thunderstorms was well to the south by that time, and while there were still rumbles of thunder, the severe weather was over.
It was certainly unusual, and for those residents – a bit scary, but it was not a funnel cloud or tornado. It was likely a phenomena called “ducting”, and the Tallahassee National Weather Service office addressed it in the special statement below. (Thanks Tallahassee NWS!)
WWUS82 KTAE 100018
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TALLAHASSEE FL
718 PM EST WED MAR 9 2011
JACKSON-CALHOUN-INLAND GULF-INLAND FRANKLIN-GADSDEN-LEON- INLAND JEFFERSON-LIBERTY-INLAND WAKULLA-COASTAL GULF-COASTAL FRANKLIN-COASTAL JEFFERSON-COASTAL WAKULLA-SEMINOLE-DECATUR-GRADY-THOMAS
718 PM EST WED MAR 9 2011 /618 PM CST WED MAR 9 2011/
…STRANGE SOUNDS BEING REPORTED ACROSS THE FLORIDA BIG BEND…
THERE HAVE BEEN SEVERAL REPORTS OF VERY STRANGE SOUNDS FROM THE WOODVILLE AREA SINCE ABOUT 645 PM EST. THE NATIONAL WEATHER SERVICE BELIEVES THIS PHENOMENON IS BEING CAUSED BY THUNDER FROM DISTANT LIGHTNING STROKES… BOUNCING OFF A VERY STABLE LAYER ABOVE THE GROUND. THIS IS CALLED DUCTING…AND CAN ALLOW SOUND TO TRAVEL UNUSUALLY LONG DISTANCES. THIS SOUND HAS BEEN MISTAKENLY ATTRIBUTED TO POSSIBLE TORNADOES…BUT WE AT THE NATIONAL WEATHER SERVICE WANT TO BE VERY CLEAR THAT THERE ARE NO TORNADOES … AND NONE ARE EXPECTED.“
I’d like to know Before someone attributes this phenomena to man made climate change.
Here’s the basic idea: