Southern MB remains under a severe thunderstorm watch this afternoon as a low pressure system over eastern North Dakota draws a warm and humid airmass northward. Morning thunderstorm activity has pushed into the northern Interlake this afternoon, while the south gets a temporary reprieve from the severe weather. However, as the North Dakota low moves into southern MB later today, a flow of warm and humid air will be drawn over southeast MB while a cold front pushes in from the west. This will set the stage for additional severe thunderstorms to develop, especially over the Red River valley and southeast MB. Strong winds and large hail will be the main threat, however favourable wind shear profiles over southeast MB may give the threat of tornadoes with any supercell thunderstorms that develop.
As this low pressure system moves north into the Interlake tonight, it will deepen into an almost fall-like storm by Saturday morning with strong west to northwest winds developing on the backside of the low. Gale warnings have been issued for the MB lakes with west to northwest gales of 40 knots forecast for Saturday. This will likely generate large waves over the south basins of Lakes Winnipeg and Manitoba with possible shoreline erosion problems on eastern and southern shores. Temperatures will also be unseasonably cool Saturday with highs only in the mid teens along with occasional rain making it feel more like September than mid July. Not a good day for Grand Beach unless you like windsurfing!
Ha, windsurfing! Better hope you are wearing a GPS tracker!ReplyDelete
Tornado Watch issued for the RRV of ND/MN, with supercells predicted to start firing off later this afternoon. NWS cites the 20 to 22Z timeframe for first initiation. With bulk shear values of 60knots and higher things could get interesting. 500mb winds are forecast to exceed 80knots later this afternoon, a potentially dangerous situation yet again!
Nice line of supercells developing over northern MN (feeding on 29/24 airmass east of the red River!) Looks like main severe threat will pass well south and east of Winnipeg this evening just affecting the extreme southeast for the next few hours. Cold frontal trough now through Portage and should be passing through Winnipeg in the next hour or two. Then it's a taste of fall coming up for tomorrow.ReplyDelete
Yeah.. tomorrow looks dreadful. System will become vertically stacked as surface low deepens to 989 MB (!!) and is 'captured' under the upper 500 MB low. Deformation type axis will set up around Winnipeg tomorrow. Lots of large scale ascent will have wrap around moisture to play with.. the result may be an area of steady rain and very cool temps for July.ReplyDelete
Precip totals could get high especially in the interlake with embedded convection. I have a feeling we could set a record low maximum tomorrow. It all depends if some clearing can sneak in late day from the northwest.. at this point it doesn't look likely from Winnipeg east.
We need these upper disturbances breaking off the main Aleutian low to weaken a bit and start tracking further north. This would allow the main band of westerlies to lift up to around 55 N... and we could tap a warm, quiet summer like regime.
What would be the record low high for today? Forecast calls for 17C, I don't think it'll get warmer than that with the rain moving in.ReplyDelete
Record low max for today in Winnipeg is 14C back in 1883.. so we won't beat that. Still, we're a good 10C below normal for this time of year. Will summer heat ever arrive this year?? In addition, rare mid-July gales on the south end of Lakes Winnipeg and Manitoba today.. gusts to 44 knots (80 km/h) being recorded on the east shores of the lakes. Doppler radar showing NW winds of 60-65 knots (100+ kmh) above 3000 ft.ReplyDelete
I'm more worried about the very high winds for this after noon.ReplyDelete
Winds WNW at 30, gusting to 69.
And at 11.50 a.m. the trees are really moving here downtown.
If temps would have dropped a bit more last night, we would have come very close to breaking the record. The daily low so far actually occurred at approx 3 pm as the heaviest rain bands passed thru. Sure looks like a lake enhanced streamer coming off Lake Manitoba right now passing west of Winnipeg.ReplyDelete
That was crazy. I had to heat the house. Most years the AC runs 24 hours a day in July. The wind was wild in south River Heights but no harm done.ReplyDelete