Operations Manager and Meteorologist with Ice & Environmental Services at Provincial Aerospace Ltd. I've been weather forecasting since 2000.
By: BwalshNLWeather , 9:17 AM GMT on March 31, 2014
Snow and ice pellets have already begun across much of Southern Newfoundland this morning and will continue for the next 36-48 hours, ending Wednesday morning as the main associated low moves out to the Grand Banks. The snow should begin lightly this morning for the St. John’s-Metro region and intensify to heavy snow later this afternoon or early evening. There will be a very sharp cut-off between significant snow and next to nothing for some areas; for instance, areas of Central NL (Gander, Grand Falls-Windsor) may see up to 5 cm in total, while the Northern Peninsula sees just a few flurries. A slight adjustment in the track of the low, and the associated area of precipitation, will make a significant difference in the final snowfall totals. Additionally, snow will be mixed at times with ice pellets, and freezing rain, particularly over the South Coast, Burin and Southern Avalon Peninsulas, which will cut down on the total snowfall amounts. The highest amount of precipitation is likely to occur over the South Coast, Burin and Southern Avalon Peninsulas; however, much of the precipitation falls as ice pellets, which does not accumulate as much as snow. Therefore, the highest snowfall will occur over the Northern Avalon and Northern Burin Peninsulas, and inland areas of the South Coast (west of the Burin) where 40+ cm is possible by Wednesday morning.
Timeline for St. John’s and the Northeast Avalon:
Monday 9 AM – Noon: Flurries developing. Wind east 20-30 km/h.
Monday Noon – 6 PM: Snow and blowing snow. Snowfall amount 4-6 cm. Wind east 35 gusting to 55 km/h.
Monday 6 PM – Midnight: Snow, at times heavy, and blowing snow. Risk of ice pellets. Snow/ice pellet amount 8-10 cm. Wind east 40 gusting to 60 km/h.
Tuesday Midnight – 6 AM: Snow, at times heavy, and blowing snow. Risk of ice pellets. Snow/ice pellet amount 8-10 cm. Wind east 40 gusting to 60 km/h.
Tuesday 6 AM – Noon: Snow, at times heavy, and blowing snow. Risk of ice pellets. Snow/ice pellet amount 7-10 cm. Wind northeast 45 gusting to 70 km/h.
Tuesday Noon – 6 PM: Snow and blowing snow. Risk of ice pellets. Snow/ice pellet amount 6-8 cm. Wind northeast 45 gusting to 70 km/h.
Tuesday 6 PM – Midnight: Light snow and blowing snow. Snowfall amount 3-5 cm. Wind northeast 45 gusting to 70 km/h.
Wednesday Midnight – Noon: Light snow ending. Snowfall 2-3 cm. Wind northeast 40 gusting to 60 km/h.
Snowfall and Ice Amounts by Wednesday Morning:
St. John’s-Metro: 35-50 cm snow/ice pellets
NW Avalon (north of TCH): 30-50 cm snow
Southern Avalon (south of TCH): 15-25 cm snow; 5-10 cm ice pellets; 2-5 mm freezing rain
Clarenville/Bonavista/Terra Nova: 15-25 cm snow
Burin Peninsula: 15-25 cm snow; 5-10 cm ice pellets; 5-10 mm freezing rain
South Coast (Port aux Basques to Connaigre Peninsula): 40-55 cm snow/ice pellets
Compounding the problem of significant snow, and ice pellets, will be strong east/northeast winds which continue into Wednesday across Southern Newfoundland, including the Avalon Peninsula with gusts consistently from 60-80 km/h through the storm, creating considerable blowing and drifting snow, producing whiteout conditions at times in heavier snow. Winds steadily diminish Wednesday night, into Thursday, behind the low.
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