Water Supply Outlook for Alberta

September 2004

August 2004 Precipitation

Most areas of Alberta recorded above-normal to much-above-normal precipitation, through much of north central Alberta recorded below-normal to normal precipitation and much-below-normal precipitation was recorded in northeastern Alberta and in High Level (Figure 1). Much-above-normal precipitation was recorded in southern Alberta with the exceptions of Drumheller and Coronation which recorded normal precipitation, and Lethbridge which recorded below-normal precipitation. Pincher Creek, Medicine Hat and Empress recorded 3 to 4 times their normal precipitation for August (Figure 2). Highest precipitation totals for the month were recorded in the mountains and southwest of Calgary (Figure 3).

Summmer Precipitation (May 1, 2004 to August 31, 2004)

Much of Alberta recorded summer precipitation ranging from near-normal to above-normal with the exceptions of the High Level, Fort Chipewyan and Fort McMurray areas which recored much-below-normal precipitation, and the Grande Prairie , Pincher Creek and Medicine Hat areas which recorded much-above-normal precipitation (Figure 4). In southern Alberta, areas south of Calgary recorded above-normal to much-above-normal precipitation. Areas north of Calgary recorded mostly normal precipitation except for Drumheller and Red Deer, which recorded above-normal to much-above-normal precipitation (Figure 5). Summer precipitation has been highest in southern mountain areas, the northern foothills, and the Slave Lake area (Figure 6).

Winter Precipitation (November 1, 2003 to April 30, 2004)

The entire province recorded below-normal to much-below-normal winter precipitation except Peace River and Cold Lake which recorded near-normal precipitation (Figure 7), and Empress which recorded above-normal precipitation (Figure 8). Winter precipitation totals are shown in Figure 9.

Soil moisture at the end of this period, May 1, 2004, was measured by Alberta Agriculture. Most of the province's soil moisture is below-average, with areas east of Calgary and Drumheller much-below-average. Average soil moisture conditions exist in the area between Peace River and Slave Lake, in a narrow band through Edmonton, and along the Saskatchewan border from the Lloydminster area north towards Fort McMurray. Soil moisture conditions are drier than last spring, but not as dry as in 2000 or 2001. A map of Alberta Agriculture's findings is available here.


Fall Precipitation (September 1 to October 31, 2003)

Generally, precipitation recorded in both northwestern and central Alberta varied from near-normal to much-below-normal, while much-above-normal precipitation was recorded in northeastern Alberta (Figure 10). In southern Alberta, precipitation totals generally ranged from near-normal to much-above-normal except at Pincher Creek, Lethbridge, Coronation, Drumheller and the Bighorn Dam where much-below-normal precipitation was recorded (Figure 11). Despite generally good precipitation totals (Figure 12) ,soil moisture conditions are very dry in most areas of the province, since late summer was generally very dry and much of the autumn precipitation fell as snow. The only area having average fall soil moisture is in east-central Alberta, along the Saskatchewan border. A map showing soil moisture conditions in the province is available from the Alberta Agriculture website through this link.

Long-Lead Precipitation Outlook

Environment Canada's long-lead precipitation forecast for Alberta issued on September 1, 2004 for the period September through November 2004 is for above-normal precipitation, except for the northern third of the province, where below-normal to normal precipitation is forecast, and the southeast corner of Alberta, where normal precipitation is forecast. The long-lead forecast for December through February is for below-normal winter precipitation, except in the northern third of the province, where normal to above-normal precipitation is forecast. Environment Canada's long-lead precipitation outlook is available from their website located at: http://weatheroffice.ec.gc.ca/saisons/index_e.html.

The National Oceanic and Atmospheric Administration (NOAA) long-lead precipitation forecasts issued on August 19, 2004 for September though November 2004 is for an equal chance of normal, below-normal or above-normal precipitation for southern Alberta. There is a chance El Nino conditions may develop this fall, and as a result warm temperatures and below-normal precipitation are forecast for southern and central Alberta for December through February. NOAA's long-lead precipitation outlook is available from their website located at: http://www.cpc.ncep.noaa.gov/products/predictions/90day/.

For technical enquires about this web page please contact Alberta Environment - Environmental Management Water Management Operations Branch at AENV-WebWS@gov.ab.ca