Today in Weather History…March 8…The Ash Wednesday Storm

March 7, 1962 was Ash Wednesday, the high holy day signifying the beginning of the Lenten period. An unusual series of factors were coming together to create an especially bad situation along the U.S. East Coast.

There was a new moon, which meant spring tides along the coast that “sprung” higher than they normally would. Twice every 29.5 days, the Earth is aligned with the sun and the moon and the gravitational pull on the tides is greater, making the tidal range higher. This is called syzygy. At syzygy, high tides are higher than they normally would be.

The second factor was that the moon was at perigee. The moon’s orbit around the Earth is not perfectly circular. It is shaped more like an oval. The Earth is located closer to one end than the other, meaning that once during each orbit, the moon is much closer to Earth than at other times. Nearly 225,000 miles closer in fact. When the Earth and moon are at the closest point, it is called perigee. Again, the proximity of the moon results in higher tides than normal.

The two events occur within 36 hours of each other a few times each year. On March 6-8, 1962, they were within 30 minutes of one another. In this case, the factors combined with a huge late season nor’easter, known as the Great Atlantic Storm to meteorologists. Locals christened it the Ash Wednesday Storm.

The storm system had its forward progress blocked by high pressure to the north, for three days. During this time, the huge extratropical storm unleashed its fury without warning from North Carolina to New England. With each succeeding high tide, water levels rose higher and higher, inundating beachfront communities. Massive waves pounded 500 miles of beach, eroding the dunes. When it was over, 1800 structures were destroyed. Damages totaled $500 million. Forty people died.

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