One indication of how wet it has been in much is the country is that less than 10 percent of the contiguous United States was under any type of drought advisory this week.

That’s an all-time low since the U.S. Drought Monitor folks have been keeping score.

Drought certainly isn’t of any immediate concern anywhere around here. For the last 30 days precipitation has been significantly above normal in every county on both sides of the river and in Delaware.

Another soaking is due to get underway Saturday night, persist through Mother’s Day, an continue into Monday rainfall amounts up to 2 inches possible.

Meanwhile, that spritz of rain that was measured officially on Friday (0.01 inches at Philadelphia International Airport, marked the 10th consecutive Friday of at least a trace of rain officially in Philadelphia.

And, yes, sometimes patterns get into these cycles in which the rinse cycles show up on the same days of the week, and it typically has to do with the natural spacing of systems as they travel through the atmosphere.

The Northeast and Mid-Atlantic have been spared the cosmic spring rainfalls that inundated parts of the Midwest.

But, “The country, as a whole, has been in a generally wet pattern,” said Curtis Riganti, of the National Drought Mitigation Center, which is responsible for the weekly Drought Monitor maps that are updated weekly and published on Thursdays.

The center, an academic-government partnership operated out of the University of Nebraska, uses a “kind of complicated” system for classifying levels of dryness.

In working up the maps it consults a mix of data that includes precipitation totals, stream-flow rates, and satellite and radar observations.

It breaks down the level of dryness in six categories from “none” to “exceptional drought” or in the category beneath it, “extreme drought.”

In all 90.17 percent of U.S. land fell under the “none” designation as of Thursday. That’s a record high for data that goes back to 2000, beating the 88.88 of the previous week.

U.S. drought map; white indicates absence of dry conditions.
National Drought Mitigation Center
U.S. drought map; white indicates absence of dry conditions.

Like about everything else involving the atmosphere, drought patterns are anything but linear. In August 2012, almost 80 percent of the country was “abnormally dry” or drier.

Drought map for Aug. 28, 2012.
Drought map for Aug. 28, 2012.