Weather conditions
Meteorological Service of Canada’s Quebec Weather Watch Map

Sectors located in the medium vigilance zone
Additional rainfall amounts are expected today over southern and central Quebec. Expected amounts are in the order of 15 to 30 mm.
Confidence level: Moderate
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Until the beginning of next week, an atmospheric blockage will allow several days of dry weather with little or no precipitation.
The weather alert bulletins issued by ECCC can be found at the following link.
The multi-hazard vigilance map, compatible with mobile technologies, is available to the public on the Quebec Data website via the following link.
Vertical inputs
24 hour vertical inputs – May 3 – 11:15am

Vertical inputs for the next 24 hours are expected to be less than 20 mm across Quebec.
Vertical Inputs 48 hours – May 3 – 11:15 am

Despite the absence of a low-pressure system, vertical inputs associated with melting will be able to reach peaks in excess of 20 mm in places where there is still snow to melt.
72 hour vertical inputs – May 3 – 11:15am

The warm weather associated with the absence of a low-pressure system will accelerate the melting of the remaining snow at higher elevations as well as in the more northerly areas of the province. This will result in vertical inputs of 15 to 30 mm in 72 hours.
Consequences on watercourses
Rivers have been experiencing significant increases in flow and water levels since Monday, following the rainfall received. These increases are more significant in the regions from the Outaouais to Charlevoix. Flood peaks have been reached, or will be reached today, for the smaller and more reactive rivers. Peak flood levels will be reached in the next few days for the larger rivers.
Today’s precipitation may cause small streams to become reactive again. The North River in the Laurentians, the Assomption River in Lanaudière and the Saint-Charles River in Quebec City will be particularly watchable, as they are still rising with high flows.
The Ottawa River is currently rising on the main stem, near the major flood stage at Fort-Coulonge and in medium flood stage near Gatineau (at Britannia Park). Other major thresholds may be reached in the next few days on the main stem. Downstream, it is at 7485 m3/s at Carillon Dam, above the medium flood level and stabilizing. Peak flooding is expected around Thursday. The Thousand Islands, Des Prairies and Lake of Two Mountains rivers are rising and will continue to do so for the next few days. Lake of Two Mountains is above its average flood level. Rivière des Prairies is above the minor flood level and Rivière des Mille-Îles is expected to remain around the monitoring level for the next few days.
The Saint-Maurice River is currently slightly above its monitoring threshold and will continue to rise gradually until tomorrow. It is not expected to reach flood stage at this time.
Lake Saint-Pierre is rising and stabilizing. It will remain just below the average flood level until May 6 in connection with the high tide period.
Source: MSP and partners (ECCC, DFO’s IML, MELCC, CPRRO, Hydro-Québec and Hydro-Météo)
Table of rivers that will reach thresholds in the next few daysjours

Forecast – Montreal Archipelago

Useful Links
In addition to the flood monitoring bulletin, public information is available on various partner and Department of Public Safety (DPS) websites.
Year-round information :
New version of Vigilance – Flood Watch
Don’t forget to change the site in your browser’s favorites! General public access : https://vigilance.geo.msp.gouv.qc.ca
- Carte vigilance multirisque
- Niveaux et débits du lac Ontario et du fleuve Saint-Laurent diffusés par le Conseil international du lac Ontario et du fleuve Saint-Laurent (CILO-FSL)
- Accumulation de précipitations – centre météo UQAM;
- Niveaux et débits des rivières et des principaux réservoirs du bassin versant de la rivière des Outaouais de la Commission de planification de la régularisation de la rivière des Outaouais (CPRRO)
- Prévisions hydrologiques et hydraulique de l’Archipel de Montréal du ministère de l’Environnement et Lutte contre les changements climatiques, de la Faune et des Parcs (MELCCFP).
- Lien vers les données de températures et précipitations par région
- Lien des données vers Hydro-Québec.
- cruesgrandmontreal.ca/

