Happy Canada Day!
Supercell thunderstorm with tops reaching over 45,000 feet into the atmosphere may have produced a tornado in the Renfrew, Ontario, region. The worst of that cell ended up tracking north of Ottawa this afternoon.
The thunderstorms over Ontario today were ahead of a pressure trough type front. The main cold front with the cooler air will approach the region tomorrow, but the best dynamics for severe thunderstorms will be farther east and include southeastern Quebec and perhaps western new Brunswick Wednesday afternoon and evening.
Behind the front, much cooler and less humid air will spread from the eastern Prairies to Ontario Thursday and Friday.
This same front will interact with Arthur as it tracks north and northeast over the next two days. I am concerned that the northwest sector of Arthur could impact Nova Scotia on Saturday with a brief period of heavy rain and gusty winds. However, the new ECMWF model just came out and turns Arthur more toward the ENE as it goes north of 40 degrees north and keeps most of the nasty weather off the coast. We should have a better idea late Wednesday and Thursday whether or not Arthur impacts Nova Scotia.
June 2014 temperature anomalies
The image below shows the preliminary temperature anomalies for June 2014.
Not nearly as much negative (cool) anomalies as we have seen recently.
Flooding continues to be a major problem from Saskatchewan to Manitoba due to recent, heavy rainfall.
Brandon, Manitoba, had near 10 inches (250 mm) of rain during the month of June. Normal June rainfall for Brandon is just over 3 inches (75 mm).
Progressive pattern across southern Canada over the next 6 to 10 days. Also a look at the sea surface temperature anomalies.
Forecast pattern clues through most of July.
Thunderstorms this weekend and a look at the long range.
Some new clues to the summer and fall season.
Amplified jet stream pattern will keep forecasters on their toes over the next week or so.
Weather pattern clues for the next several weeks.