Tag: Convection

Slowly Improving Weather in Store

Brad Leave a comment

The weather will slowly improve over the next couple days as some warm air begins to slowly push across the Prairies.

3hr. Cumulative Precipitation for late this afternoon

3hr. cumulative precipitation from the RDPS for late this afternoon.

Today will remain mostly cloudy across Southern Manitoba with two main features to pay attention to. The first feature is a low pressure system that will slide from Southern Saskatchewan into North Dakota, bringing with it a chance of showers through southwest Manitoba through the morning and into the early afternoon. The second feature will be a trough slumping southwards through the Interlake into the Whiteshell. The southern extent of this trough will move through the Red River Valley in the late afternoon and evening, and as it enters the area, a few scattered convective showers or flurries will develop along it and move through the region. Whether we see rain or snow will depend on the exact timing of the system and what the temperature is; either way, accumulations will fairly insignificant and the showers likely won’t be widespread. Daytime highs will be around 6°C this afternoon.

After these systems pass, we’ll see skies slowly clear out overnight as temperatures drop to around the -3°C mark. A ridge of high pressure begins working it’s way into Manitoba; skies will remain mainly sunny as temperatures slowly climb. Tomorrow we should see daytime highs around 9°C through the Red River Valley, and increasing up to around 11°C for Friday. We’ll see a mix of sun and clouds on Friday as a weak system brings some cloud through the Red River Valley as it passes through central Manitoba.

The weekend looks relatively average, with no indications so far that any significant precipitation events are in store for us over the next week.

Summer is Pushing Into Southern Manitoba

Brad Leave a comment

The beautiful conditions we’ve had over the past while will take a slight break today, with notably summer-like weather pushing over the Red River Valley. With the Red River and Assiniboine River rapidly rising, how much rain will we see?

A low pressure system currently in Eastern Montana continues to push warm air northwards through the Dakotas towards Southern Manitoba. This warm air brought thunderstorms to Eastern Montana and the Dakotas overnight, and as they have pushed northwards, they have lifted up over the warm front and transitioned to elevated convection that, while weakened, is producing an area of rain that is pushing into our area.

As this precipitation continues to move northwards, away from the warm front, it will weaken as it looses it’s precipitation generating support. The rain that currently resides over the international border will slowly push north, and could give a few light showers to Winnipeg late this morning before it peters out. The main weather that will impact us is currently developing over southeastern Saskatchewan and Southwest Manitoba.


This area of rain visible on the southern edge of the RADAR image will continue to blossom as the low strengthens and overall lift in the area intensifies. This will then begin to track east-northeast later today and spread an area of rain across Southern Manitoba, including the RRV. The models are having some difficulties determining how much precipitation this will produce, which is to be expected, however their tracks for the precipitation are beginning to agree.
GEMLAM

GEM-GLB

GFS

NAM

These models are all from their respectice 06Z runs, except the GEM-GLB which is the 00Z run, showing the precipitation accumulation from 00Z – 06Z tonight. The NAM is a big lighter on the precipitation, but other than that, they all agree (more or less) on location and intensity of the rain. So what will happen?

The precipitation accumulation will vary significantly depending on the amount of embedded convection that manages to develop. Current indications are that after a few showers late this morning, rain will begin to push across the Red River Valley late this afternoon or early this evening. The rain should end over the Southern RRV overnight as the low pulls further north and shifts the precipitation north as well. In Winnipeg, the rain should end sometime early tomororw morning; likely before 8 AM. Total rainfall amounts are difficult to pin down, as it will be directly proportional to the amount of convection that develops, but I would put my money on a general area of 5-10 mm (1/5 – 2/5”). If any significant convection should develop, some areas could potentially see up to 15mm of rain (~ 1/2”).

Once this precipitation clears out, the rest of the weekend will remain a little unsettled. The warm front maintains its position across ND, which will result in the chance of rain over the RRV as convection rides up over the warm front into Southern MB. Next week looks quite nice, however, with mostly sunny skies and temperatures in the low-to-mid teens. How all this precipitation will affect the river levels remains to be seen, however any accumulating precipitation has people concerned with the extremely high river levels that already are impacting the RRV. For more flood information, Rob over at Rob’s Blog has put together a nice collection of flood links.