The potent weather system that brought severe thunderstorms and a destructive tornado outbreak to the southern U.S. this week will continue to track up the Atlantic coast Thursday and Friday. Gulf moisture from this system will clash with a late season shot of arctic air to produce a swath of significant March snow fover parts of Atlantic Canada. Rain and snowfall warnings are in effect, as well as widespread special weather statements that span Nova Scotia and Newfoundland. A slight shift in the storm track could tip accumulations one way or the other, but with a widespread 15-20 cm threatening the region. More on the timing and impact, below.
Low-pressure system moves into Atlantic Canada later Thursday, starting as rain, but transitioning over to snow as colder air presses in
Snow continues across Nova Scotia on Friday, while Newfoundland sees a sharp temperature contrast with heavy rain for the Avalon
Brief shot of colder temperatures in the wake of the system before warming trend later in the weekend
THURSDAY THROUGH FRIDAY: BRIEF, BUT POTENT BLAST OF LATE WINTER WEATHER
A late winter storm will take aim at Atlantic Canada to end the week, as a low pressure system offshore will push moisture back into the cold air that will be pressing in across the region.
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Ahead of the incoming front, light rain will break out across Nova Scotia late Thursday, but as cold air spreads across the region overnight, precipitation will then change over to snow, becoming heavy by Friday morning for the south coast including Halifax.
Meanwhile, a sharp contrast will set up across Newfoundland, with heavy rain expected for the Avalon and heavy snow across central parts of the island through Friday. As the front continues to press east, St. John's will switch over to mixed precipitation before ending as snow.
Snow diminishes across Nova Scotia late Friday, with totals ranging from 5-15 cm across the southwest, but up to 20-30 cm for the northeast.
"Halifax is expected to see 15-20 cm, but the gradient in snowfall totals will be sharp, so a slight shift in storm track could tip those numbers one way or the other," says Weather Network meteorologist Michael Carter.
Rainfall warnings are in place for parts of Newfoundland, with between 30-50 mm of rain expected across the Avalon, but ending with 5-15 cm of snow.
"The frozen ground has a reduced ability to absorb this rainfall," warns Environment Canada. "If possible, storm drains should be cleared before tonight, as a combination of rain, snow melt, and runoff will likely lead to minor flooding in areas where pooling water cannot drain properly."
Areas to the west that see mainly snow will stack up to 20-30 cm, with 30+ cm possible in the terrain favored areas.
Strong southerly winds ahead of the front late Friday will also impact the Avalon, with gusts between 80 and 100 km/h expected. As temperatures fall below freezing Friday night, conditions will likely become quite icy as well.
"This storm will quickly depart by the weekend, leaving behind sunny skies and a warming trend into early next week," Carter adds.
Things will be feeling more like April and even early May with temperatures reaching the mid to upper teens for the southern and central Maritimes through next week. Couple that with abundant sunshine and there will be no doubt that the seasons have flipped the switch.
Be sure to check for the latest updates on this incoming storm and its track dependent totals.