Severe weather likely on Sunday, one or two tornadoes possible
Several rounds of thunderstorms are possible—one in the morning, followed by another in the mid-afternoon to early evening hours. One or two tornadoes are possible.
Keep an eye on the radar and stay aware of watches and warnings in your area. Know where to go and what to do if a tornado warning is issued for your location.
DON'T MISS:
Severe weather likely on Sunday
Sunday will kick off with an early-morning mesoscale convective system (MCS) expected to develop stateside.
This organized line of thunderstorms will push into northwestern Ontario and head toward the Thunder Bay area. Expect this first round of storms between 8:00 a.m. and 12:00 p.m. local time.
A second line of severe thunderstorms will develop and approach the area during the afternoon hours.
Large hail, gusty winds, heavy rainfall, and one or two tornadoes are possible in these storms. The environment is favourable for rotating thunderstorms near the international border, including Fort Frances and Atikokan.
STAY SAFE:
There remains some uncertainty in the timing and coverage of the lines of storms in northwestern Ontario, as they depend on the timing of the cold front's arrival and the atmosphere's ability to destabilize itself amid the wildfire smoke over the region.
Folks across southern Manitoba, including Winnipeg, could see severe thunderstorms fire up beginning Sunday afternoon as a low-pressure system moves into the region. The main hazard from this cluster of storms will be large hail and heavy rainfall.
Stay with The Weather Network for all the latest on this evolving severe weather threat.
Header image created using graphics and imagery from Canva.
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Hamilton Spectator
3 hours ago
- Hamilton Spectator
P.E.I. precipitation no longer in the range considered acid rain
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Acid rain is a phenomenon that includes any form of precipitation with acidic components, such as sulfuric or nitric acid, that falls to the ground from the atmosphere in wet or dry forms. To improve air and water quality, industrial factories began to separate the sulphur compound by what is known as a scrubber, said van den Heuvel. 'It turns into gypsum, the same stuff in some people's walls. They were able to obtain quite dramatic reductions of sulphur very quickly, which was the main form of acid rain,' he added. While acid rain still can occur occasionally, it is less severe than it used to be, said van den Heuvel. P.E.I. has never had major impacts from acid rain, van den Heuvel said. It all has to do with the geology, he added. Because P.E.I.'s groundwater contains fair amounts of calcium and magnesium, it has been able to resist the acidic changes within the soil, said van den Heuvel. 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She added that acid rain usually has a pH ranging between 4.2 and 4.4. In P.E.I., precipitation samples are collected at the Southampton air monitoring station at the eastern P.E.I. forestry office. The monitoring station is equipped with a collection system that gathers and stores precipitation for measurement, Vanlderstine said. A bucket is used to collect rainfall and other forms of precipitation, allowing for an accurate assessment of the accumulated volume, she added. 'Each week, the collected precipitation is transferred to sample bottles and sent to the P.E.I. analytical lab for chemical analysis,' Vanlderstine said. The station also features an automated sensor that detects precipitation events. 'When precipitation begins, the sensor triggers the opening of a protective lid, allowing rainfall and other precipitation to enter the collection bucket. Once precipitation stops, the lid automatically closes to prevent contamination,' Vanlderstine said. 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The major sources of SO2 and NOX in the atmosphere are the burning of fossil fuels to generate electricity, vehicles and heavy equipment emissions, manufacturing, oil refineries and other industries. Yutaro Sasaki is a Local Journalism Initiative reporter, a position funded by the federal government. He can be reached at ysasaki@ and followed on X @PEyutarosasaki . Error! Sorry, there was an error processing your request. There was a problem with the recaptcha. Please try again. You may unsubscribe at any time. By signing up, you agree to our terms of use and privacy policy . This site is protected by reCAPTCHA and the Google privacy policy and terms of service apply. Want more of the latest from us? Sign up for more at our newsletter page .


CNN
11 hours ago
- CNN
A major cooldown is coming for the US, but there's a catch
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CNN
11 hours ago
- CNN
A major cooldown is coming for the US, but there's a catch
It's been an abnormally hot summer in much of the eastern half of the United States with multiple punishing heat domes, sweltering nights and plenty of humidity to go around, but some relief is finally on the horizon. A major weather pattern change beginning later this week will bring high temperatures more like early June — nearly 20 degrees cooler than they are now — to millions currently reeling through some of summer's most intense heat. The upcoming cooldown is tied to an expansive area of high pressure expected to track south out of Canada later this week, and a lengthy cold front racing down ahead of it. The north-central US will be the first beneficiary of cooler conditions on Wednesday and more of the eastern half of the US will follow in the coming days, with some of the coolest temperatures coming just in time for the weekend. But a dramatic cooldown like this always comes at a cost, and in this case it's rain and thunderstorms with a renewed risk of flash flooding for areas that have already been hit hard during a summer full of it. Here's when the heat will finally break and where flooding could become an issue later this week. More than 150 million people from the central US to the East Coast are under a Level 3 of 4 or Level 4 of 4 heat risk Tuesday, according to the National Weather Service, as high temperatures climb into the 90s and the heat index soars even higher. It's another brutal day of heat for the dozens of cities and towns from the East Coast to the Mississippi Valley that are having one of their 10-hottest summers to date as of July 27, according to data from NOAA's National Climatic Data Center. Stretches of extreme heat are getting more intense and lasting longer as the world warms due to fossil fuel pollution and colder spells like the upcoming one are becoming less common. It isn't unheard of to have a handful of cooler days in the latter part of summer, but the upcoming change will feel especially jarring given how hot previous weeks have been. Temperatures will ease dramatically on Wednesday from the north-central US to parts of the Northeast. Chicago, for example, will soar into the 90s Tuesday but struggle to even reach 80 degrees on Wednesday. The cooling trend will continue Thursday with widespread temperatures in the 70s in much of the Plains, Midwest, Northeast and parts of the Ohio Valley. St Louis will reach the upper 90s Tuesday, the low 90s on Wednesday and might barely hit 80 degrees on Thursday. Temperatures will ease in the South too, though not nearly as drastically as farther north. Little Rock, Arkansas, could hit 100 degrees on Tuesday and Wednesday, but reach the mid-90s by Thursday. Friday, the first day of August, could be the coolest day of the week for parts of the Midwest, Ohio Valley and Northeast. New York City's high temperature on Friday will only reach the mid-to-upper 70s after being in the mid-90s Tuesday and Wednesday. Friday's high in New York City is similar to what the city records in the first days of June. After high temperatures near 97 degrees on Tuesday and Wednesday, Washington, DC, could have a high in the upper 70s on Friday, which happens on only a few days each August. High temperatures are typically in the 80s in August in the nation's capital. Cooler conditions will finally reach more of the South over the weekend. Atlanta hasn't had a high temperature less than 80 degrees since May, but that streak could finally be broken on Sunday. Areas farther north will be quite pleasant over the weekend as high pressure remains in place. The cooler conditions will not last forever. The latest forecasts from the Climate Prediction Center indicate above-normal temperatures are likely to return during the first full week of August. Stormy weather could stretch over a large portion of the central and eastern US on Wednesday as humid air pours north out of the Gulf and the cold front starts to slice south. Storms spark to life when cooler, drier air and very warm and humid air clash, like what's expected this week. Wet weather will also be drawn out over multiple days given the slow trek south of the cold front. Parts of the Midwest are under a Level 2 of 4 risk of flooding rainfall on Wednesday with a massive Level 1 of 4 area stretching from the Gulf Coast to the Northeast, according to the Weather Prediction Center. The real concern begins Thursday for areas that have dealt with disruptive and deadly flooding this summer. A Level 2 of 4 risk of flooding rainfall is in place for parts of the Northeast and mid-Atlantic, including New York City, Philadelphia and Washington, DC. Nearly all of New Jersey is in the risk area. The state has been slammed by flooding this summer, including when at least two people were killed two weeks ago. The increased risk also includes parts of Virginia that have flooded multiple times this season. The flood risk shifts south into the Carolinas and part of Georgia on Friday, more states all too familiar with serious flooding this summer. Tropical Storm Chantal's flooding rainfall killed at least one person in North Carolina in early July.