It was not only that Monday’s rain was the heaviest in the Washington region in almost three months. The hours of gray skies, showers and downpours also produced what appeared to be a remarkable meteorological coincidence.

At three of the sites where the National Weather Service makes official observations, the amount of rainfall that fell through 5 p.m. Monday was the same. It was not about the same, it was exactly the same.

The figure given for Reagan National Airport was 1.13 inches. The figure given for Dulles International Airport was 1.13 inches. And the reading taken in Charlottesville was 1.13 inches.

How often such a coincidence appears was not immediately clear. But it seemed unlikely that it happens very often.

It did not appear that any widespread conspiracy existed to record 1.13 inches of rain everywhere. The figure given for Baltimore, for example, was 0.84 inches.

In Washington, Monday brought the first rainfall this month. The amount almost matched the total for all of last month, which was 1.22 inches.

It was not far short of the August total of 1.34 inches, and it was the most in Washington since 1.39 inches fell on July 12.

The sense of storminess was enhanced by winds that gusted up to 41 mph at National, driving raindrops into faces and windshields.