Environment Canada has issued a blizzard warning for St. John’s, the Avalon Peninsula and southern areas of Newfoundland from the west to east coast.
In St. John's-metro, snow and blowing snow are expected to begin late tonight, with accumulations of 2 to 4 cm, except 10 cm along the Southern Shore.
Northeast winds are forecast to gust up to 70 km/h overnight, with the temperature rising to- 3 C by morning.
The forecast for St. John's-metro Tuesday morning is snow, at times heavy and blowing snow, with another 20 cm falling and northeast winds gusting to 90 km/h.
Tuesday night, mpre snow or rain is expected, with a low temperature of -1 C.
Range of 20-30 cm possible for Avalon region
Environment Canada says current indications suggest total snowfall accumulations on the Avalon will range from 20 to 30 cm, combined with winds gusting as high as 90 km/h to create blizzard conditions with near zero visibility.
Snow and blowing snow are forecast to develop tonight on the entire Avalon and southern areas of the island from west to east, with strengthening northeasterly winds as a low pressure system tracks towards the island from the south.
Environment Canada says these conditions will continue into Tuesday as the low approaches the Avalon, but there remains some uncertainty regarding whether the centre of the system will pass over the Avalon Peninsula or just to the southeast. If the low takes the more westward track, winds would shift to a southerly direction over southern parts of the Avalon, likely causing precipitation to change through freezing rain to rain on Tuesday afternoon.
Conditions are expected to begin to improve late Tuesday as the low moves away.
The weather office warns that travel is expected to be hazardous due to reduced visibility.
The blizzard warning applies to all the Avalon Peninsula, Bonavista Peninsula, Clarenville, Burgeo-Ramea, Burin Peninsula, Terra Nova, Channel-Port aux Basques and vicinity and Connaigre region.
There area also winter storm watches for Buchans and the interior, central Newfoundland including Gander, Grand Falls-Windsor.
Environment Canada says at this time, there is some uncertainty regarding the track of this system, making it difficult to predict exactly how much snow will fall over central parts of the island. Current indications suggest amounts will likely reach at least 10 cm by late Tuesday, but the potential exists for higher totals, especially as the snow continues into early Tuesday night.
Travel is expected to be hazardous due to reduced visibility in some locations.
All weather warnings and advisories for Newfoundland are online at https://weather.gc.ca/warnings/index_e.html?prov=nl
Second low-pressure system, snow expected to turn to rain on east coast
There are also special weather statements for most of the island as a result of a second low-pressure system,
Environment Canada says as one low pressure system departs from the island Tuesday evening, bringing snow and strong winds to all but northernmost parts of the island, a second low is forecast to quickly follow from the south by early Wednesday.
“There is considerable uncertainty regarding the track of this second system, but the latest consensus suggests its centre will likely track west of the Avalon Peninsula.” Temperatures are expected to climb above 0 C to the east of its track.
The weather office says snow, in advance of this system, is expected to spread northward across Newfoundland after midnight Tuesday night, but will likely change to rain over eastern parts of the island as temperatures rise. The rain or snow will taper off over most areas on Wednesday morning, except on the Northern Peninsula where the snow may persist throughout the day.
Extreme cold warnings in Labrador
There are also extreme cold warnings in effect for Labrador City/Wabush and the Churchill Falls area.
Environment Canada says a frigid airmass is expected to bring extremely cold temperatures into the -30s Celsius to these regions. Even the slightest breeze will cause extreme cold wind chills of minus 45 C this morning.
To report severe weather, send an email to weatherNLWO@ec.gc.ca or tweet reports to #NLwx.