Foghorn array at Portland Headlight, Maine, Christmas Morning, 2010.
A moisture-laden, cold snowstorm (locally named a "Northeaster" or even more locally "nor'easter") is arguably the most severe weather North America's northeastern seaboard can "dish out". It is thus named because although it approaches from the west or south south west, storm winds in the northern hemisphere rotate counterclockwise and so when a Northeaster arrives its brutal winds pound the coast from the northeast.
During a Northeaster visibility is typically reduced to 1/4 mile and less; temperatures can drop into the teens Fahrenheit with gusting winds. Ocean water temperatures run between the mid to high 30's F in the winter months, and so the water is immediately deadly to anyone who finds themselves overboard.
Virtually the entire coast of Maine is rock ledge. The Portland Headlight is strategically located on this ledge, to warn ship captains who are navigating their vessels out of the oceanic shipping lane and into Maine's principal commercial harbor at Portland, Maine.
This was the first lighthouse in Maine, commissioned by the first President of the United States, George Washington and completed in 1791. The lighthouse has a posted range of 24 nautical miles. But of course, in a snow storm the light's and fog horn's ranges would be reduced.
But from personal experience during Northeasters (in this area) I know that the super-low frequency blast from this little horn can be heard as far away as Falmouth, and I am confident even further. It blasts every 15 seconds. I now reminisce to the times when, as a teenager in the mid-1960's, I earned money by shoveling snow from people's driveways. A big snow storm earned you about $4.00 per driveway and required all of 1 to 1.5 hours of hard cardio work. Let's put it this way, when you finished shoveling through just one Northeaster the "love handles" were completely gone!
The ambience of a Northeaster minus the wind is serenity and near silence, because of the absorbing effect of the snow. But the eery, low-frequency and very-far-off sound of this little horn was ever-present in that ambience during a Northeaster.
I have just "Google Earthed" the distance from that neighborhood to the horn you see in this image. That distance is approximately 6+ miles, within about 1/4 mile. And this neighborhood is 6+ miles BEHIND, or inland, of these ocean-facing horns. Yet, the eery sound is still very audible through the driving storm. Low-frequency sound travels immense distances.