LEVELnews

Great Lakes–St. Lawrence River Water Levels
Volume 21, Number 1

8 January 2013

PDF Version (414 KB)

Michigan–Huron Sets New Record Low Monthly Level

Although levels are still preliminary and need to be verified, it appears that Lakes Michigan–Huron has set a new record low level for the month of December. The lakes’ December 2012 monthly mean level was 1 cm lower than the old record low for the month set in 1964. The lakes’ beginning-of-January 2013 level matched the lakes’ 1918–2011 period-of-record low for the beginning of January set in 1965.

  • Lake Superior’s level fell 5 cm during December, 3 cm less than its 1918-2011 period-of-record average December decline of 8 cm.
  • Lakes Michigan–Huron’s level fell by 2 cm during December, half of its average decline of 4 cm for the month of December.
  • Lake Erie’s level fell by 1 cm during December instead of increasing as it typically does during the month. On-average, Lake Erie’s water level has increased 1 cm during December over the 1918-2011 period of recorded.
  • Lake Ontario’s level increased by 9 cm during December, much more than its average December increase of 1 cm.
  • Montreal Harbour’s monthly mean level in December was 12 cm higher than the harbour’s monthly mean level in November and 6 cm above its period-of-record low for December set in 2007. The harbour’s December level was 92 cm below average and 68 cm lower than last year.
Great Lakes Water Level Information
 December 2012 Monthly Mean LevelBeginning-of-January 2013 Level
LakeCompared to
Monthly Average

(19182011)
Compared to
One Year Ago
Compared to
Beginning-of-Month
Average
(1918
2011)
Compared to
One Year Ago
Superior34 cm below3 cm below34 cm below3 cm below
Michigan-Huron72 cm below43 cm below71 cm below41 cm below
St. Clair37 cm below54 cm below39 cm below52 cm below
Erie17 cm above58 cm below19 cm below60 cm below
Ontario25 cm below34 cm below21 cm below37 cm below

Water Level Forecast

Water levels are expected to decline on each of the lakes during January, with the exception of Lake Ontario, which is expected to rise. Montreal Harbour's monthly mean level in January is expected to rise compared to its December level.

For a graphical representation of recent and forecasted water levels on each of the Great Lakes and on Lake St. Clair, compared to their 1918–2011 period-of-record monthly averages and extreme levels, please refer to the December 2012 edition of the Canadian Hydrographic Service’s monthly water levels bulletin.

Period of Record

Although it is now 2013, the period of record used for comparison purposes in the bulletin and LEVELnews is still 1918–2011, and will likely remain so for a couple more months. The 2012 water level data needs to be verified and accepted as correct before the period-of-record statistics used for water level purposes can be updated to 1918–2012.

High and Dry in the East

The higher than normal temperatures and a lack of rainfall in Eastern Canada was selected as one of Canada's top ten weather stories for 2012. The warm, dry weather meant a great summer for most outdoor enthusiasts but trouble for some crops and water systems. Although not record dry (of 65 years, 13 summers were drier across the Great Lakes and the St. Lawrence River basin), the lack of rain and excessive warmth was notable and has contributed to the decline in levels experienced basin-wide. For the full story on this and the other nine top Canadian weather stories for 2012 please visit Environment Canada’s website, click on the “Weather and Meteorology” link under Topics, and then on the “Top Ten Weather Stories for 2012” link in the Highlights section on the Weather and Meteorology webpage.

December Precipitation over the Great Lakes*
Great Lakes Basin92%Lake Erie
(including Lake St. Clair)
98%
Lake Superior58%
Lakes Michigan-Huron90%Lake Ontario143%
December Outflows from the Great Lakes*
Lake Superior77%Lake Erie87%
Lakes Michigan-Huron86%Lake Ontario88%

*As a percentage of the long-term December average.
Note: These figures are preliminary.

For more information:

Chuck Southam (Editor)
Boundary Water Issues Unit
MSC – Operations Ontario
Environment Canada
P.O. Box 5050
Burlington ON L7R 4A6
Tel.: 905-336-4955
Fax: 905-336-8901
Email: water.levels@ec.gc.ca

Jacob Bruxer
Great Lakes–St. Lawrence Regulation Office
MSC – Operations Ontario
Environment Canada
111 Water Street East
Cornwall ON K6H 6S2
Tel.: 613-938-5725