Hot and Humid Conditions Ahead

Temperatures will soar this weekend in Winnipeg as a hot and humid air mass moves in from the south.

A building upper ridge will push increasingly hot and humid conditions into southern Manitoba this weekend. The first push of heat will arrive today with the temperature climbing to around 30°C in Winnipeg. Skies will stay mostly sunny through the day with light winds. Tonight will be warm with a low near 18°C.

Saturday will be another hot day with increasing humidity. The city will see variable cloudiness through the day depending on (a) how much blow-off from overnight thunderstorms in Saskatchewan and western Manitoba moves through in the first half of the day, and (b) how much thunderstorm activity develops in the afternoon. Winnipeg should see a high near 31°C, but may be warmer or cooler depending on how much sunshine there is. Dew points will gradually climb through the day, reaching the mid- to upper-teens by the end of the afternoon. Combined with the warm temperatures, this will result in humidex values in the upper 30s.

The thunderstorm threat for the day is largely conditional; a strong capping inversion will likely preclude any surface-based convection through the afternoon. There will be steep mid-level lapse rates coupled with strong dynamics that may support elevated convection, though. The first organized threat will be midday if any convection from Friday night manages to survive through the morning. Conditions should be more settled for the afternoon, then a risk for thunderstorms will redevelop late in the day. We recommend you view ECCC’s Thunderstorm Outlook on Saturday morning for the authoritative look at the day’s convective potential. You’ll be able to view it in our Bulletin Viewer.

The warm conditions continue on Saturday night as winds ease off and then turn northwesterly by Sunday morning. Winnipeg will see a low near 19°C.

Sunday will usher in drier conditions as breezy westerly winds up to 30 gusting 50 km/h develop. Temperatures will again climb to around 30°C, but dew points will drop back into the single-digits, making for more comfortable conditions. Any leftover cloud in the morning will quickly clear out, leaving behind partly cloudy skies for the rest of the day. Temperatures will dip to a mild low near 17°C on Sunday night with winds easing.

Long Range Outlook

Next week will bring a fair amount of sunshine to the region with daytime highs generally in the 25 to 30°C range. No major precipitation events are forecast, however there may be one or two chances for thunderstorms through the week.

Today’s seasonal daytime high in Winnipeg is 25°C while the seasonal overnight low is 12°C.

Mixed Bag of Weather Ahead

Winnipeg will see pleasant summer weather on Monday and Wednesday while Tuesday brings cloudier, unsettled conditions.

Winnipeg will kick off the work week with a pretty beautiful day as temperatures soar to a high near 27°C under partly cloudy skies. Winds will also stay light too, out of the west at 10 to 20 km/h. This evening, cloud cover will begin to build into the region as a disturbance approaches from the west. Heading through the night, Winnipeg will see a chance of showers with the risk of a thunderstorm. Temperatures will dip to a low near 15°C.

Tuesday will bring mostly cloudy skies to the city as the disturbance moves through the Red River Valley. The cloud cover will keep temperatures a bit cooler with a high near 23°C. Winnipeg will see a continued chance for some showers with the risk of a thunderstorm through much of the day. The wind will pick up out of the northwest in the afternoon to around 30 km/h than ease in the evening. Skies will clear out late in the day in Winnipeg and temperatures will head to a low near 12°C.

Showers or thunderstorms will move across southern Manitoba Monday night through Tuesday.
Showers or thunderstorms will move across southern Manitoba Monday night through Tuesday.

Wednesday will bring plenty of sunshine back to the region with temperatures rebounding back into the upper 20’s. Winnipeg will see a high near 27°C with westerly winds near 20 km/h. Skies will stay clear on Wednesday night with a low near 13°C.

Long Range Outlook

An upper ridge will build over the region through the second half of the week, bringing significantly warmer temperatures. High temperatures in Winnipeg will climb towards 30°C by the weekend with partly cloudy skies expected both Thursday and Friday.

The heat hits in full this weekend, with daytime highs near 30°C and overnight lows near 20°C. Conditions will become more unsettled on the weekend as more humid conditions build into the region. Both Saturday and Sunday may bring the chance of showers and thunderstorms to the region.

Temperatures are forecast to moderate next week, with daytime highs in the mid- to upper-twenties and lows in the mid-teens.

Today’s seasonal daytime high in Winnipeg is 24°C while the seasonal overnight low is 12°C.

Hot & Windy Saturday Brings Thunderstorm Threat

Today will be a scorcher over southern Manitoba as strong southerly wind pump hot and increasingly humid air northwards. With that heat, though, will come a fair amount of instability and one of the first widespread severe thunderstorm threats of the season.

To start the day, some elevated convection will move across the region, most likely through the Interlake. These thunderstorms may be strong to severe, but should remain north of the Red River Valley. Although the storms should pass north of Winnipeg, the city will still see some passing cloud as they move by. These storms and their cloud cover should clear out by midday. As the sun comes out, the wind will pick up. A tight pressure gradient over the region1 will produce southerly winds up to 50 gusting 70 km/h today, helping heat and moisture surge northwards out of the United States. With those strong winds in place, Winnipeg will see temperatures climb to a high near 33°C. It will also get a tad more humid as the day goes on as dew points rise into the mid-teens.

Strong southelry winds will be in place over southern Mantioba this afternoon. To the west, a trough of low pressure extending southwards into the United States may trigger a line of thunderstorms late in the day.
Strong southelry winds will be in place over southern Mantioba this afternoon. To the west, a trough of low pressure extending southwards into the United States may trigger a line of thunderstorms late in the day.

By late in the afternoon, the thunderstorm threat will begin to build. A trough of low pressure over southwestern Manitoba into the Interlake may trigger the development of thunderstorms. If they develop, they’ll likely be strong to severe with primary threats of large hail and strong winds. Any of these thunderstorms that develop will move eastwards towards the Red River Valley through the evening. The focus then turns southwards to the Dakotas. A shortwave lifting northeastwards through the state will trigger convection late in the day. These thunderstorms will grow upscale and expand in coverage overnight. As the evening progresses, this blossoming area of thunderstorms will gradually spread across southern Manitoba. The potential for strong to severe thunderstorms exists tonight, with large hail and damaging wind gusts the primary threats. The thunderstorms should be through the Red River Valley by Saturday morning.

Temperatures will remain mild on Friday night with a low near 19°C. Those strong southerly winds will ease into the 20 to 30 km/h range this evening and then diminish to light overnight.

If thunderstorms are able to develop along the trough, southern Manitoba may see a line of thunderstorms marching towards the Red River Valley early in the evening.
If thunderstorms are able to develop along the trough, southern Manitoba may see a line of thunderstorms marching towards the Red River Valley early in the evening.

Saturday will bring plenty of cloud to Winnipeg as the low pressure system responsible for all this heat and instability moves through. Temperatures will be much cooler with morning temperatures near 18°C dropping to 14°C through the day. Winds will gradually pick up out of west into the 20 to 30 km/h range. More showers with the risk of thunderstorms are likely to develop later in the morning and persist through much of the afternoon. Conditions will calm down on Saturday night with some clear breaks developing towards Sunday morning. Winnipeg should see a low temperature near 9°C.

Sunday will bring seasonably cool conditions to Winnipeg, but things will get a chance to dry out. The city should see a high near 19°C under partly cloudy skies. Westerly winds near 30 km/h will be in place for much of the afternoon before diminishing in the evening. Winnipeg will see a low near 8°C with just a few clouds on Sunday night.

Long Range Outlook

Next week will bring seasonably cool temperatures with daytime highs around 20°C and overnight lows close to 10°C. The city will see variable cloudiness through the week, and a couple of passing disturbances may bring a chance or two of showers through the week. Temperatures should begin to warm up near the end of the week, but that may bring a return to unsettled conditions.

Today’s seasonal daytime high in Winnipeg is 23°C while the seasonal overnight low is 10°C.

  1. The tight pressure gradient is a result of a 996 mb low over western Manitoba squishing against a ridge of high pressure extending through SE Minnesota into Iowa.

More Warmth and Sunshine Ahead; Unsettled Weather Returns At End of Week

Warm weather continues in Winnipeg for a couple more days, but unsettled conditions will develop on Friday into the weekend.

Winnipeg will see mainly sunny skies today with temperatures climbing to a seasonably mild 26°C. Winds will be light for much of the day, then increase out of the south to around 20 km/h as a low pressure system approaches. The city will see a few clouds through the evening with a marginal chance of a passing shower or thunderstorm. It looks unlikely that Winnipeg will see anything, but the potential is there. Temperatures will head to a low near 12°C overnight with clearing skies.

Thursday will be a gorgeous day across the region as the upper ridge begins building in. Temperatures will climb to a high near 26°C under sunny skies with light easterly winds. The wind will pick up overnight into the 20 to 30 km/h range out of the southeast as a developing low pressure system strengthens over Saskatchewan. These breezy winds will help keep temperatures warm with a low of just 16°C expected. By early Friday morning, some cloud will spread into the region along with a chance of a thunderstorm.

Very warm temperatures will move into southern Manitoba on Friday.
Very warm temperatures will move into southern Manitoba on Friday.

For Friday, a high-amplitude trough-ridge pattern over the Prairies will drive the weather. This upper flow will result in the gradual strengthening of a slow-moving low pressure system near the Saskatchewan/Manitoba border. For Winnipeg, that means a breezy southerly flow tapping into hot air mass over the northern Plains. With winds in the 30 to 40 km/h range, temperatures will climb to a high near 30°C under a mix of sun and cloud. The city may see a chance for a thunderstorm early in the day, then the chance redevelops for Friday night. Temperatures will stay warm on Friday night, dropping only to around 20°C with southerly winds continuing.

Long Range Outlook

Early indications show a rather unsettled weekend for Winnipeg. Friday’s low near the SK/MB border will stall over the province, bringing several chances for rain or thunderstorms to the city through the weekend. The weekend will start warm, but should cool towards seasonal temperatures for Sunday. Next week looks to bring settled conditions with near-seasonal temperatures.

Today’s seasonal daytime high in Winnipeg is 22°C while the seasonal overnight low is 9°C.