The Boerne Star

Current drought on pace with record drought of 1950s

By Dave Pasley – Staff Writer

Published: Sunday, July 26, 2009 11:58 AM CDT

If there is no more rain in July the current drought, now in its 22nd month, will pull nearly even with the rainfall totals recorded at the same stage of the 39-month-long “drought of record” in the mid-1950s.

Since the current drought began Oct. 1, 2007, only 27.95 inches of rain have fallen in Boerne. At the 22-month mark of the 1950s drought, from November of 1953 through August of 1955, the cumulative rainfall recorded in Boerne was 27.44 inches

While it is a significant milestone, local weather watcher and Cow Creek Groundwater Conservation District Director John Kight says it would be premature to put the current drought in the same category with the 1950s drought.

“The length is what sets the 1950s drought apart from the many others we’ve had here over the last century,” Kight said. “If it starts raining this fall and winter, the current drought will likely end up somewhere in the top five. But if the weather patterns don’t change and this drought persists, its similarity to the 1950s drought is pretty scary.”

The primary reason the current drought has caught up with the 1950s drought is the 4.09 inches of rain that fell in August, 1955 ??“ that drought’s 22nd, and wettest, month.

Over the next 17 months, through January of 1957, only 16.3 inches of rain was recorded in Boerne, an average of less than one inch per month. In comparison, the monthly average has been 1.27 inches. in the 22 months of the current drought.

For the current drought to match the 1950s drought, the next year and a half would have to be even drier than the last two years have been.

Rainfall records for Boerne began in 1893, a very dry year when less than 17 inches of rain was recorded. In the 116 years since then, through December 2008, the average annual rainfall has been 33.75 inches and the median is 32.8 inches.

“That sounds like a long time, and it is helpful to have these records, but you need to be cautious in putting too much stock in them,” Kight says. “Maybe the last century has been drier than normal, maybe it’s been wetter. We don’t really know for sure.”

The current drought is closing in on the 24-month record for dryness. If less than 1.61 inches is recorded between now and Sept. 30 the current drought would beat the 24-month record of 28.33 inches set between November, 1953 and October, 1955.

The 12-month record, however, is safe. From June, 1947 through May, 1948 barely nine inches of rain was recorded, including a five-month stretch from August 1947 through December, 1947 when there was no recorded rainfall.

The record for the driest consecutive calendar years is 1954-1955, with 29.56 inches. Second place goes to 1955-1956 with 31.32 inches. Outside of the 1950s, the record for a two-year dry spell is 38.36 inches set in 1947-1948.

The five driest years on record are 1954, 10.29; 1956, 12.05; 1947, 14.59; 2008, 14.74; and 1893, 16.96.

So far in 2009 rainfall has totaled 11.06 inches.

Both the current and the 1950s droughts have had “false stops,” a wet month or two followed by a return to dry conditions.

When the four inches of rain fell in August 1955, residents may have thought the drought had ended, only to find out they would have to endure 17 more bone dry months before the drought would actually end.

During the current drought more than five inches of rain fell in August, 2008 ??“ but then it took the combined rainfall totals from the next seven months, September 2008 through March of this year, to accumulate the next five inches of rain.

False stops aside, rainfall records show that dry spells tend to begin and end abruptly.

The 1950s drought ended when 3.46 inches of rain fell in February, 1957, followed by another 26-plus inches of rain over the next four months. By year-end 52.55 inches of rain had fallen in Boerne, making 1957 the ninth wettest year on record.

A 1999 dry spell, the sixth driest year on record, was followed by three wet years when rainfall totaled nearly 163 inches.

Perhaps the ultimate paradox is that 2007, the year the current drought began, was also the fifth wettest year on record, with 59 inches of rain recorded.

“I guarantee it will rain again,” Kight said. “But I can’t guarantee when that will be.”

Copyright © 2009 – The Boerne Star

Comments are closed.