Maritime weather: When and where will receive much-needed rain

Extended periods of dry weather in the summer and throughout the fall have contributed to a developing drought situation in the Maritimes. Fortunately, the prevailing weather pattern favours the arrival of more rain this week.

Much of the region is rated as being abnormally dry or in moderate drought at the end of October.

Rain deficit and drought

At the end of October much of the Maritimes was rated as being in either abnormally dry or moderate drought conditions by Agriculture and Agri-Food Canada.

Going back to the month of June, most areas in the region are running a rainfall deficit of about 125 to 300 mm.

One of the drier areas has been Halifax County in Nova Scotia where some municipal watersheds are low to the point where communities have been asked to voluntarily conserve water. It will likely take a few month of near-to-above normal rainfall to make up for the deficit that has developed.

On average. June, July, and August are the months with the least amount of precipitation for the Maritimes, while October, November, and December, are the month with the most.

Rain totals from June through November 18th at selected sites in the Maritimes compared to 30 year averages.

Mid-November rain

The Maritmes have had some damp weather in past days.

Going back to last Thursday, a broad area of low pressure stalled just to the east of the Maritimes soaking parts of eastern New Brunswick, eastern Nova Scotia, and Prince Edward Island. The remainder of New Brunswick and Nova Scotia have only received a light rainfall with a few to several millimetres being observed.

Patchy areas of light rain and drizzle are expected Monday night into Tuesday morning. In most cases only trace amounts to a few millimetres can be expected. Localized totals of 10 to 20 mm are possible for parts of Cape Breton and eastern Prince Edward Island.

Damp weather going back to the end of last week, the most substantial rain amounts in eastern parts of the region.

Long range outlook

The next round of widespread rain is expected at the end of this week as a low pressure system develops in the northeastern U.S.

The region is expected to receive a round of rain on Friday as an associated weather front with the system moves through. A second round of rain will move through on Saturday as the centre of low pressure passes by the region. When looking that far out into the forecast there is a considerable amount of uncertainty in predicted rain totals. Some computer weather model data is showing possible totals of 20 to 60 mm Friday morning through Sunday morning.

More rain is expected Friday and Saturday in the Maritimes. It should be taken with a grain of salt, but some totals of 20 to 60 mm may be possible.

Those same weather models are showing that the low pressure system on Saturday may be intense enough to generate wind gusts reaching the warning criteria of 90 km/h for parts of the Maritimes. The location of those strong winds will depend on how the storm passes by. That will be something that comes more into focus by Wednesday of this week.