The National Weather Service in Portland issued an extreme heat warning for Sunday noon to Tuesday 5 AM PDT, advising precautions for expected high temperatures.

Memphis forecast: high near 94°F, heat index up to 101, 88% humidity. Clear evening, lows around 75°F. Similar conditions Sunday. Showers possible starting Monday.

Austin is facing a week of high temperatures near 100 degrees, minimal evening relief, and slight chances of rain, as per the National Weather Service.

Salt Lake City's weather forecast promises a break from recent heat, with today reaching 83 degrees and a cool 59 degrees at night. Temperatures will rise throughout the week, hitting mid-90s by Tuesday.

Detroit's weather forecast predicts a sunny week with temperatures in the lower 90s, clear nights around 72 degrees, and a chance of mid-week showers and thunderstorms.

A heat advisory is in effect in north central and east Texas, including Dallas, with temperatures near 99°F and heat index values up to 106. Residents are advised to take precautions due to the risk of heat-related illnesses.

Seattle's forecast predicts pleasant weather, with clear skies and comfortable temperatures peaking at 79°F today and climbing higher into the week, according to the NWS.

Heat advisory for Oklahoma and parts of Texas with heat index values up to 107 degrees, risks of heat-related illnesses.

Houston's weekend forecast predicts a mix of calm and stormy weather, with chances of thunderstorms up to 60% on Sunday and high heat indices. No immediate tropical threats, but ongoing monitoring of Atlantic disturbances.

New Orleans is set to experience intermittent showers and thunderstorms for the upcoming week, with highs around 88-89 degrees and mild easterly winds.

Boston experiences pleasant weather with 81 degrees and light winds today, but a heatwave with high humidity is forecasted to start on Sunday, peaking midweek with heat indices in the upper 90s.

Phoenix, AZ faces intense heat with highs nearing 110 degrees; slight evening relief. National Weather Service forecasts persisting heat, with a slight chance of rain later in the week.

Scattered thunderstorms and high humidity expected in Miami, with the National Weather Service predicting high temps, a significant chance of precipitation, and possible thunderstorms throughout the week.