Massachusetts faces an air quality alert due to Canadian wildfire smoke, affecting sensitive groups. Temperatures are high, but a reduction in smoke and cooler weather is expected soon.

Portland forecast: Overcast morning, partly sunny with a high near 74°F, calm wind. Evening to cool to 57°F. Upcoming days show partly sunny skies, chance of showers midweek, and a sunny weekend with temps up to 93°F.

The remnants of Tropical Cyclone Gil will reduce trade winds and bring warm, muggy conditions with increased showers to Hawaii, as per the National Weather Service.

The Bay Area is experiencing strong winds with gusts up to 45 mph, leading the NWS to issue a warning. Temperatures are expected to rise with some areas at moderate HeatRisk levels, and an elevated fire risk persists due to dry conditions.

Las Vegas faces a heatwave with an Extreme Heat Watch; the Gifford Fire affects air quality, and the NWS advises caution for aviation and community heat risks.

The NWS predicts sunny days with rising temperatures for Memphis, with a slight chance of showers on Tuesday and highs potentially reaching mid-90s by the weekend.

San Diego is expected to experience higher temperatures midweek, with hazy conditions due to the Gifford Fire. The NWS issued an Extreme Heat Warning for some areas and a Heat Advisory for others. Fog may affect morning commutes.

Sacramento's weather forecast predicts a heatwave with sunny days and rising temperatures, reaching highs up to 98 degrees throughout the week. Evening temperatures will cool slightly.

San Antonio is expecting a hot week with near 100-degree temperatures, a chance of showers and thunderstorms, and little relief from the heat in the evenings.

Denver is set to experience a heatwave with temperatures above the average, while an Ozone Action Day Alert warns of poor air quality for sensitive groups.

Salt Lake City faces extreme heat and fire risk, with a high of 98 degrees and windy conditions leading to a Red Flag Warning for critical fire conditions in certain zones.

El Paso is facing a severe heatwave with temperatures possibly exceeding 105 degrees, prompting the National Weather Service to issue an advisory. Residents are advised to take precautions against heat-related illnesses.

Detroit's weather forecast predicts a week of warm, sunny conditions with occasional areas of smoke and light winds, according to the National Weather Service.