New health risk warning signs regarding hydrogen sulfide have been installed in parts of the Tijuana River Valley, including a QR code linking to a County website.

Minneapolis forecasts sunny skies and mild temperatures, with highs nearing 82 degrees and calm winds. Nighttime may bring patchy dense fog and a small chance of showers and thunderstorms later in the week.

Chicago experiences a break from intense heat, with sunny and mild weather forecasted, including highs in the low 70s to low 80s, and comfortable evening temperatures.

The Knoxville area is expected to have a mix of clear skies and potential thunderstorms in the coming days, with varying temperatures and wind conditions.

The Bay Area Air Quality Management District has settled with Tesoro Refining to boost air monitoring and transparency at its refinery, following disapproval of previous plans.

Nashville officials warn of extreme heat and advise caution, issuing a heat advisory with OEM conducting Heat Patrols distributing water and urging awareness of heat-related illness symptoms.

The National Weather Service issued a Heat Advisory for the Bay Area, with expected high temperatures and a Moderate HeatRisk cautioning against heat-related illnesses. Elevated fire weather conditions are also anticipated due to dry vegetation.

Seattle's weather is clearing up to sunny skies with highs around 74°F today, increasing to the mid-80s by the weekend, with calm and clear nights in the low 60s.

The Southwest is expecting a heatwave with temperatures 3-10 degrees above normal, with a cooling trend starting Tuesday, amid chances of showers and thunderstorms.

Los Angeles faces extreme heat with a warning issued for August 21-22, expecting temperatures between 95 to 105 degrees, resulting in potential heat illness risks.

Moderate to breezy trade winds, maintained by high pressure, are expected in Honolulu along with a stable and dry weekend forecast by the NWS. An increase in windward showers is also predicted.

Las Vegas issued an Extreme Heat Warning and Heat Advisories for high temperatures that may stress residents and the power grid, with nighttime offering little relief. Monsoonal moisture also poses risks of storms with potential flash flooding.

The National Weather Service forecasts a continuation of hot and sunny weather for Sacramento, with temperatures nearing 100 degrees and light winds providing limited relief.