Soil moisture reserves rebounding across parts of province

By Al Beeber - Lethbridge Herald on September 21, 2024.

LETHBRIDGE HERALDabeeber@lethbridgeherald.com

Soil moisture levels thanks to a relatively wet early fall have allowed soil moisture reserves to rebound dramatically across most of the south and north east regions of the province, says the Alberta government. Reserves have also rebounded through the eastern half of the central region.

However, the situation is drastically different in other areas where deficits which are approaching 12 to 25-year lows are occurring, specifically much of the north west region of Alberta, the Peace region and much of the west-central areas of the Central region.

“It is estimated that some lands currently need 50 to 75 mm of moisture to bring soil moisture reserves to near normal for this time of year. However, many other dry areas now only need 25 to 50 mm of precipitation to bring soil moisture reserves to where they normally are this time of year,” said the province in this week’s agricultural moisture situation update.

Since the last report on Sept. 4, conditions have been relatively wet across the southern and north east regions. The greatest amounts of rain – 87.5 millimetres – were recorded at the Hussar AGDM station with most falling within a 36-hour period starting in the evening of Sept. 11.

As of Tuesday, most of Alberta’s agricultural lands had not yet experienced frost and only a few areas have seen temperatures dip below 0C, says the province.

About 50 per cent of the time, most agricultural areas won’t see frost until about the third week of September with no killing frosts – temperatures -4C and colder – until late in the month or early October.

“For many areas with recent rains, the 60-day precipitation accumulations are now trending to at least near normal across most of the province, with drier than normal conditions still persisting in and around Red Deer, north of Edmonton, and across the extreme western and northern

Peace Region. For many areas, there has been a positive shift in moisture patterns in recent weeks. However deep year-over-year deficits still exist across many lands,” says the province.

The La Nina weather system is expected to materialize late in the fall and there is presently a 71 per cent chance it will hit by November. It’s expected to stick around until as late as March.

“However, experience with the meteorological record has shown that at this point nobody really knows for sure what Mother Nature has in store for us this winter,” adds the update.

As of Thursday before Friday’s rain, storage in several southern Alberta reservoirs was in the normal range. St. Mary Reservoir had storage of 49 per cent – it’s normal range is 41 to 75 per cent. Waterton Reservoir was at 52 per cent storage within the norm of 33 to 63 per cent. The Oldman Reservoir was slightly below normal at 64 per cent. It’s normal range is 69 to 83 per cent.