A heat alert has been issued by Niagara Public Health.
Officials say it will go into effect Friday.
Temperatures are expected to reach or exceed 31 degrees C with the overnight lows near 20 degrees C and may continue through the weekend.
The high tomorrow is 30, but it will feel more like 34.
The low overnight tonight is 22 and Saturday it is 21.
Niagara residents are advised to take extra precautions during episodes of extreme heat and humidity.
Signs of heat-related illness may include confusion, dizziness, nausea, muscle swelling, heart disturbances, and headache.
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