A week that was to already go down in history for its record-setting rainfall got another meaningful shot of moisture in the early morning hours Saturday when a Severe Thunderstorm sweeping through much of the Southwestern corner of the Province impacted Brandon.
At any other time, the story on the morning would be the frequent lightning and thunder that no doubt gave more than a share of residents an early wakeup call. Within the context of recent events, rain was however again the theme with gauges in Brandon indicating accumulation amounts unofficially appearing to be in the range of 15-25mm (2/3-1 inch).
The city was left with reports of power outages including a downed power line on the North Hill. Information on outages in the area can be learned on Manitoba Hydro's outages page.
Environment and Climate Change Canada had issued a Severe Thunderstorm warning just prior to 5:15am with the system on Brandon’s doorstep, lifting it approximately an hour later with the storm giving way to daylight and morning sunrise.
The same storm appeared to move through areas to the North and Northwest including Rivers, Minnedosa and Rapid City with at least one gauge in the vicinity of the latter showing 15mm of precipitation from the morning storm.
Brandon received 155.5mm of rain on Sunday in its largest on-record single day rainfall. Tuesday brought another 33.7mm. Saturday morning’s totals appeared to comfortably push the week tally over the 200mm (8 inch) mark.
The City of Brandon shared on Friday afternoon that the Assiniboine River through the city had likely experienced a peak, with eyes continuing to be on the dam upstream at Rivers and the Little Saskatchewan River that flows into the Assiniboine West of Brandon. The Province of Manitoba reported on Friday of reduced flows over the dam relative to earlier in the week along with lowered but still historic levels in Rivers’ Lake Wahtopanah.
By Saturday afternoon, even following the latest rainfall the river at Brandon continued to trend in the right direction. At 9:16AM, the City reports an Assiniboine level drop of another ten inches from yesterday afternoon to 1173.24 feet. The Brandon Sun early Saturday afternoon reports continued receding of Lake Wahtopanah at Rivers as well as the Little Saskatchewan River downstream of the dam.
The dam continues to be monitored 24/7 after the Province stated that it had lost confidence in the structure earlier in the week. The City of Brandon indicated on Friday that the worst-case projection scenario in the event of dam failure would be an Assiniboine peaking at 2011 Flood-like levels, below the height of the city’s dike system.
Saturday’s forecast calls for a 30% chance of showers with chance of a thunderstorm late this afternoon and a 30% chance of more of the same in the evening. Further rain is forecast by ECCC for Sunday.
Updated: July 4, 2:30pm. Updated levels for Saturday