Strong winds, heavy snow and rain begin for Newfoundland

Thursday, December 8, 2016, 7:24 PM - Friday is shaping up to be a particularly stormy day for Newfoundland.

A deepening area of low pressure is set to bring active weather to Newfoundland late this week, including gusty winds, rain for the Avalon Peninsula, and 5 to 15 cm of snow for the western part of the island.

WINTER IS HERE: With La Niña helping shape global patterns what will Canadians expect from winter? Find out with The Weather Network’s 2016 Winter Forecast | FORECAST & MAPS HERE

Snow flurries began to break out over western Newfoundland through the day on Thursday, in advance of the main system. Snowfall warnings were in place by the evening hours, with a handful of snow squall watches also in effect.

"Snow is expected to develop overnight [Thursday] night and become heavy at times early Friday morning," Environment Canada said in a statement. "Total snowfall amounts near 15 cm are expected through the day Friday."

The track of the deepening low still presents some forecast challenges, but current guidance suggests that temperatures should remain above the freezing mark for the Avalon through the event, resulting in the bulk of precipitation, 10 to 15 mm, falling as rain for locations like St. John’s.

Winds will strengthen by Friday morning, continuing through the day with gusts exceeding 75km/h for some coastal locations. With lingering snowfall in the west, as well as fresh snow on the ground, this brings up the concern for reduced visibilities from blowing snow, and even periods of blizzard-like conditions for parts of the province on Friday. This will likely lead to very hazardous road conditions and significant travel complications to end the week.

On the western side of the low’s track, most of the rest of Newfoundland with the exception of the immediate southern coast will see temperatures remain at or below the freezing mark through the event.

This should lead to a majority-snow event, with 5 to 15 cm piling up by the time snow winds down on Friday morning. The highest amounts should be found along the west coast, where sea enhancement should help increase totals to near 20 cm.

With the present forecast track of this storm, temperatures will be relatively mild for the eastern half of the island (forecast daytime highs are around 4˚C), allowing the majority of the forecast precipitation to fall as rain for the Avalon.

Much like rainfall totals on the east, there is significant uncertainty in the forecast snowfall accumulations, however a conservative preliminary estimate of 10-20 cm is possible for western sections and 5-10 cm for central areas.

As the low continues to wind up over the North Atlantic through the weekend, gusty winds and sea-effect snow should linger into early next week.

Forecast uncertainty

At this time, there remains some uncertainty regarding exactly where the storm will intensify most rapidly in the vicinity of Newfoundland on Friday, which will have a direct impact on forecast precipitation amounts.

If the storm intensifies rapidly south of Newfoundland, the aforementioned conditions may be on the conservative side.

However, if it intensifies after it passes over the island, winds will be much stronger along the northeastern peninsula as the storm departs Friday evening, and the heaviest snowfall may be concentrated to the more remote regions of the northern peninsula.

Rest assured the meteorologists here at The Weather Network will be keeping a close eye on this developing storm, and provide you with key updates as they become available.  But for now, be prepared for a stormy end to your week.

Looking ahead to the weekend, bands of sea effect snow and below seasonal temperatures are in the forecast. A significant system looks to track across the region early next week, with rain to the south and snow to the north.