Several rounds of severe thunderstorms have left parts of the Pembina and Red River Valleys drenched Tuesday morning. Not one, not two, but three waves of severe thunderstorms rolled through the region, with Warnings issued for the Morden, Winkler and Altona areas three times between late afternoon Monday and early this morning.
"The first round of storms developed mid-afternoon Monday, and that was followed by a second round early in the evening between 6 and 8 p.m., with the final round rumbling through the region between 1:30 a.m. and 3:30 a.m.," noted CMOS Accredited Weathercaster Chris Sumner. "The storms developed along a warm front that was pushing northward into Southern Manitoba from North Dakota, and then they were essentially riding along that front in a generally easterly to northeasterly track. Because the front was moving northward relatively slowly, many points within those warning areas saw three rounds of significant rainfall, which is reflected in our Rainwatcher readings this morning."
For the latest forecast details, click here.
Sumner noted it is unusual to have see Severe Thunderstorm Warnings issued in mid to late September, because typically the atmospheric conditions necessary to produce that kind of weather is usually not present.
"Severe weather potential is dictated by moisture availability, instability and shear in the atmosphere as well as a trigger to get things started," he said. "Usually, by this point in September, instability and atmospheric moisture are not within the range to kick start things. That wasn't the case yesterday as warm, moist air being pumped into the region by an upper southwesterly flow made things possible, along with the trigger of that warm front."
The first round of severe thunderstorms also prompted Tornado Warnings for the R.M.s of Hanover (including Steinbach), La Broquerie, Ste. Anne and Reynolds. Environment Canada issued the Warnings based off Doppler RADAR imagery which indicated rotation in one particular thunderstorm cell.
Meanwhile, Manitoba Hydro is responding to outages across the Red River Valley. As of 8 a.m., more than 2,500 customers were without power including St. Jean, Morris, Rosenort and surrounding rural areas east and west of Highway 75.
The following rainfall totals are for Monday, September 16th through 5am Tuesday, September 17th and are courtesy PembinaValleyOnline Rainwatchers and the Manitoba Ag Weather Network:
Plum Coulee - 138mm (5.52 inches)
Winkler (south of city) - 131.1mm (almost 5.25 inches)
Arnaud (west of) - 130mm (5i2 inches)
Horndean (north of village) - 125mm (5 inches)
Schanzenfeld - between 125 and 135mm (based on several reports)
Rosenfeld - 121.7mm (almost 4.8 inches)
Windygates - 112.7mm
Winkler (west side of city) - 112.5mm (4.5 inches, includes several mm's from weekend)
Morden (two miles south) - 100mm (4 inches)
Morris - 91.5mm (3.66 inches)
Reinland - 84mm
Gnadenthal/Dominion City - 83.6mm (3.3 inches)
Morden (north side of city) - 77.5mm (3.1 inches)
Gretna - 74mm
Steinbach - 68.8mm (2.75 inches)
Kane - 68.1mm
Altona - 60mm (2.4 inches)
Woodmore - 42.5mm (1.7 inches)
Jordan - 19.2mm (almost 8/10th)
Manitou - 14.9mm
Clearwater - 14.3mm
Carman - 11.8mm (almost 1/2 inch)
Elm Creek - 8.2
25mm = 1 inch
A warm and humid day is in store for Tuesday, with highs around 25 and feeling like 33, and a mix of sun and cloud expected. According to Sumner, similar conditions are expected for Wednesday, with southerly surface winds continuing to move warmer air into the region.
"Starting Wednesday night, we are looking at multiple chances for showers through the end of the week and into the weekend," he noted. "A couple of upper level lows will bring those chances, but there are a number of factors that will play into whether we see additional severe thunderstorm activity, with the next potential possibility Wednesday afternoon and evening. Generally speaking, temperatures are expected to start trending downward Thursday and into the weekend, with seasonal, to slightly below, conditions forecast for the start of next week."
Average daytime highs for now are 19 degrees daytime and 6 degrees overnight.
