All sorts of weather extremes going on over the past couple weeks across Canada and the United States.
In the West, we have a very large trough (pocket of cold air aloft) extending from western Canada through the southwestern U.S. with a significant storm system tracking northward into Saskatchewan. Snow has been heavy with gusty winds from Montana through extreme eastern Alberta and western Saskatchewan. The storm will continue into the northern Plains tonight as the snow ends on its western side. The map below shows expected snowfall.....
East of the storm track, the surge of warm air continues with Winnipeg already at +21 C this afternoon. Average temperatures over the past week in southern Manitoba have averaged over 17 C above normal! Unheard of for such an extended period.
Farther east, we could see afternoon temperatures close to 27 celsius (80 F) during the midweek as the summer-like Atlantic high pressure ridge reaches its peak. This ridge has been a monster by March standards and will not give up easily.
Any ice left on the Great Lakes?
According to the Canadian ice service, there was still some small pockets of ice in the northern half as of March 12th (most recent ice concentration update see below), but it is going fast. All open water on the shallower Lake Erie.
The image below shows the concentration of ice across the eastern Great Lakes on March 14th, 2011. Quite a change!
Normally, total ice coverage across the Great Lakes as a whole reaches its peak right about now (green line) with about 40% coverage, according to the chart below. As of March 12th, only 3% of the Great Lakes was covered with some ice.
The lack of sea ice and snow cover has allowed more of the sun's energy to get absorbed (darker surfaces) and go directly toward heating the surface and not melting ice/snow.
Large storm clashing with warmth and higher humidity will lead to heavy rainfall and locally severe thunderstorms over the Prairies the next couple of days.
Potential for localized rainfall amounts in excess of 100 mm (4 inches) over western Alberta this week....
Here is my latest interpretation of the ECMWF weekly update that goes into mid-July.....
Potential for strong thunderstorms and heavy rainfall Wednesday/Wednesday night.
What the latest ECMWF seasonal forecast output shows for July, August and September...
Below is my interpretation of last night's release of the latest ECMWF model weeklies that now go out through the first week of July.