Waves, not weather, likely from storms Humberto and Imelda for the Maritimes

Waves pound the shore at Peggy's Cove, N.S. on Friday, Jan. 5, 2018. THE CANADIAN PRESS/Andrew Vaughan

A dominating area of high-pressure centered over Quebec will help steer Hurricane Humberto and Tropical Storm Imelda far enough east of the Maritimes to avoid hazardous weather. Increased waves and surf are expected from the storms by mid-week. The same high-pressure system limits our chances for needed rain as well.

The highs and lows of weather this week

A very weak cold front is dipping north to south across the Maritimes Monday night. Behind that front temperatures cool a few degrees for Tuesday. There will also be some spotty showers that develop around eastern New Brunswick, Prince Edward Island, and northern/eastern areas of Nova Scotia Tuesday afternoon and evening.

Temperatures turn brisk Tuesday night into Wednesday morning in a continuing northerly wind. Lows in the low-to-mid single digits. Wednesday itself will be noticeably cool compared to the start of this week with the daytime highs topping out in the low-to-mid teens. Scattered showers are expected to develop during the day.

Following that a developing high-pressure system in Quebec clears the sky for the Maritimes for both Thursday and Friday.

Storms steered eastward

The benefit of the high-pressure system moving out of Quebec towards the Maritimes mid-week is that it will help direct both Hurricane Humberto and Tropical Storm Imelda far enough east of the Maritimes to limit their impact to our region.

We need rain, no doubt about that, but we don’t want it in the form of a hurricane that packs other impacts such as utility outages and coastal damage.

Hurricane Humberto is forecast to pass by just far enough west of Bermuda for the island to avoid the worst of its weather impacts on Tuesday. The storm then takes a sharp turn to the east Wednesday, directed around the high-pressure building over the Maritimes, and is then well east of even the outermost marine districts by Thursday as a post-tropical storm.

Tropical Storm Imelda is forecast to develop into a Category 2 hurricane and make a more direct approach on Bermuda Wednesday. After that Imelda moves east and north around the area of high pressure centered over the Maritimes late week. It is possible that Imelda arrives in the Grand Banks marine district as a post-tropical storm on Saturday with the Canadian Hurricane Centre noting that “primary effect over Canadian waters (mainly Laurentian Fan and the Southern Grand Banks) will be strong to gale-force northerlies later this week.” The weather organization plans to release an updated statement on both Humberto and Imelda Tuesday afternoon.

Waves, not weather

Unless there is a large and very unexpected change in the forecast for Humberto and Imelda no severe weather from the storms is expected to impact on-land for the Maritimes.

The passage of the storms will churn the ocean waters and create large waves. Nova Scotia can expect an increase in wave action near the Atlantic coastline by late Wednesday. Some near coastal significant wave heights may reach two-to-three metres (three-to-nine feet) before breaking upon approach to shore. The rougher coastal conditions persisting into Thursday before possible diminishment Friday and the weekend.

The increase in wave action can also be accompanied by an increase in dangerous rip currents.