Paul Fitzsimmons, meteorologist
In a winter that has been full of challenging storms, meteorologists at The Weather Network have been hard at work putting together the forecast for the latest storm system due to affect much of eastern Canada on Friday.
As of early Thursday evening, the storm developed over Arkansas and had a swath of moderate snow extending from Kansas and Nebraska eastward into southern Iowa. The computer model guidance meteorologists use as an aid to forecast storms such as this one has come into good overall agreement as to how this storm will play out -- but as usual, the trickiest aspect is the exact details.
Like many storms this winter, this will be a storm noted for a high variation in snowfall over relatively short distances.
Subtle changes in this stormís track and evolution as it approaches cannot be ruled out and have the potential to change these amounts by a few centimetres at any given location. These types of fine details in the storm will continue to be closely monitored by forecasters through tonight with any adjustments made to the forecast as needed.
While the storm may be significant across parts of Ontario and Quebec, the highest impacts will be across the Maritimes, where snowpack is already quite deep in many places.
Timing-wise the storm moves in Friday afternoon with the meat of the storm occurring Friday night before precipitation winds down Saturday morning.
Like any storm, this storm will have a warm side to the south and east of the lowís track with the cold side setting up to the north and west. The expected track will bring the storm northeastward across Nova Scotia with an area of heavy rain setting up along and south of the track through most of Nova Scotia and heavy snow to the north across parts of Prince Edward Island and New Brunswick.
The tricky details meteorologists sweat over in this situation are the exact location of the rain/snow line which will be setting up near the Bay Fundy east to near Charlottetown. Any small wobble in this placement of the rain/snow line will have impacts in the forecast for places like Saint John, Moncton, and Charlottetown.
The wind is the other story that especially needs to be highlighted in the Maritimes. Strong winds can be expected, especially on the backside of the low Friday night into Saturday, when northerly gusts will reach up to 100 km/h around the Bay of Fundy.
Impacts from this storm wonít be felt across Newfoundland until Friday night into Saturday, with a snow changing to rain scenario setting up through most of province including St. Johnís. Any snow amounts over St. Johnís and the Avalon will be minor before the changeover with a more prolonged period of snow setting up farther west. Amounts over 15 cm will be possible across the west coast.
Following the storm, high pressure will build in briefly before the next system affects eastern Canada early next week. Indications are that this next storm will take a track much farther north and west, bringing a warmer and wetter scenario to most areas affected by the initial storm.