CouncilBriefs

Unlike for the last few months, the map below shows no strong temperature anomalies for July. Most of the province was near normal over the whole month.The northwest, however, did turn cooler after preceding months with warmerthannormaltemperatures.

During the first week, most of the province was warmer than normal, especiallyin theeastandnortheasttowardtheQuebecborder andJamesBay.Ottawareachedahighof33.6oC onJuly6th.Nearnormaltemperaturesdominated the second and third weeks provincewide apart from in the cool northwest. A second warm pattern then traversed the province toward the end of the month. Some of the highest temperatures included Petawawa at 34.5oC on the5th,Oakvilleat34.0oConthe4thandToronto at 31.2oC on the 28th. High humidex values of near 40 occurred in the first and final week prompting heat warnings (e.g. 41 in PortWeller onthe5thand43inWindsorandRidgetownon the28th).

Precipitation

Julywasmuchwetterthannormalinthe south, especially over the southwest where amountsreachedwellover250%ofthemonthly normal (e.g. London, 260%). In contrast, the north was much drier than normal except near HudsonBay.Thisisthethirdconsecutivemonth of below normal precipitation for most of the north. The airport in Timmins, for example, received only 31% of its mean monthly precipitation and this fell almost entirely in the first week. During the first week, intense precipitation produced high daily amounts over the southwest such as at St. Thomas (104 mm) and London (80 mm) on the 2nd. In the final week, areas near the lower Great Lakes had abundant precipitation.These amounts from the 24thto30thwerenearorgreaterthantheaverage monthly total such as at Brownsville (110 mm), Stratford (88 mm) and Burlington (85 mm) (CoCoRaHS).

SignificantEvents

July 13th: Tornadoes Cause Suburban NightmareinEasternOntario

A low pressure system tracked through southern Ontario, bringing significant rain and producing four tornadoes in eastern Ontario. Between 40 and 80 mm of rain fell from the morning through the afternoon with the highest amount,82mm,reportedinMonktonlocated56 km northwest of Kitchener. In the afternoon, severe thunderstorms struck eastern Ontario producingtwoEF-1tornadoesinBarrhavenand subsequently two EF-0 tornadoes; one in EmbrunandtheotherinFournier,aspersurveys done by the Northern Tornadoes Project. ResidentialcommunitiesinBarrhaven,asuburb ofOttawa,sustainedthebruntofthedamagewith over 125 homes affected. Roofs were ripped off homes along with damage to windows and shingles. Power outages were reported along with numerous downed trees. One person was injured after being struck by shattered glass and subsequently required stitches. The tornado in Embrun caused tree damage and minor roof damage to several homes, while the tornado in Fournier resulted in damage to crops and trees. No injuries were reported in either of those instances. movedthroughsouthwesternOntarioduringthe eveningofJuly26th,producinganEF-1tornado inthetownofBlenheimandin EF-1downburst in the Harrow-Kingsville area. The Northern Tornadoes Project confirmed the events after damage to homes, sheds, crops and trees was found in Blenheim, with one particular shed caving in on itself as found in drone footage. In Harrow and Kingsville, snapped power poles resultedinnumerouspoweroutagesanddowned trees caused significant structural damage to homes.Thestrongestrecordedwindspeedswere reported at Harrow 91km/h and Windsor InternationalAirport 87km/h. The same system also brought significant rainfall spanning from southwestern Ontario to northeastern Ontario withanaverageof40to60mmofrainreported, however an impressive 86.9 mm of rain was reportedonPeleeIsland.

July 20th:

Baseballs Fall From the Sky in SouthwesternOntario

Another low pressure system moved throughOntarioonJuly20th,bringingheavyrain to portions of northeastern and central Ontario, whilst damaging winds and hail pummeled southwesternOntario.Between30and70mmof rain was reported throughout northeastern and centralOntariowithGoreBayreceivingatotalof 72.6 mm, the highest total reported.As the cold front swept through southwestern Ontario, severe thunderstorms produced hail as large as baseballs in Courtright andAmherstburg, while Cottamreceivedtennisballsizedhail,asightnot often seen in Ontario. The Northern Tornadoes Project later confirmed that the storms also producedtwotornadoesandfourmicroburstsin additiontothehail.AnEF-1tornadooccurredin the evening in South Buxton, significantly damaging the roof of a home. Tree and crop damagewasalsofound.AnEF-0wasconfirmed inPetroliawherethetornadocauseddamagetoa barnroofaswellastrees.FourEF-0downbursts were confirmed to have occurred in Point Edward/Sarnia, Wardsville, Wilkesport, and Alvinston resulting in minor damage to homes, trees, crops, farm equipment and more significantdamagetoalargemachineshed.Peak wind gusts of 117 km/h were reported in Sarnia and 98 km/h in St. Catharines as the storms passedthrough.

July26th:DamagingWindsandHeavyRains AffectSouthernOntarioOnceAgain

Another line of severe thunderstorms

July 28th: Impressive Storm Prompts Broadcast Intrusive Severe Thunderstorm WarninginOttawa

Yet another system moved through southernOntarioonJuly28th.IneasternOntario a cold front prompted severe thunderstorm warningsintheNationalCapitalRegion(NCR) with the main concerns being large hail and damaging winds. One particular storm strengthened rapidly as it approached Ottawa, eventually prompting forecasters to issue a broadcastintrusiveseverethunderstormwarning foruptobaseball-sizedhail.Ping-pongballand golf ball sized hail were reported with some reports of up to tennis ball-sized hail in the Ottawa region. The rarely seen damaging hail caused cracked windshields, broken exterior lights and tree damage in the NCR.Afterwards, numerous additional thunderstorms formed, prompting tornado warnings and causing tree damage in Gatineau, Embrun and Russell. Funnelcloudswerealsospotted,however,there are no known confirmed tornadoes at this time. The thunderstorms resulted in over 43,000 customerslosingpowerandtherewerereportsof significant ponding and pooling on roads in the Ottawaarea.

OutlookforAugust

Temperatures are likely to be slightly above normal for much of the province with the exceptionofWindsortotheGreaterTorontoArea where there is no clear trend. For precipitation, thereisnocleartrendfortheprovince.