Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Tue Oct 01 2024 Valid 00Z Wed Oct 02 2024 - 00Z Fri Oct 04 2024 ...Record breaking heat continues over the Southwest U.S.... ...Critical fire weather risk over the Northern/Central High Plains today and tomorrow... ...Generally dry conditions across much of the Lower 48 through midweek... Approximately 35 million people in the Southwest U.S. fall within a heat alert today as a late-season heat wave keeps a firm grip over the region. Continuing the trend from the last several days, numerous record breaking high temperatures in the triple digits are expected through at least this Friday, which will support widespread Moderate to Major heat impacts across the San Francisco, Las Vegas, and Los Angeles metropolitan areas per the most recent experimental HeatRisk runs. Locally Extreme heat impacts are also expected atop the Phoenix metropolitan area today. As a reminder, the Major to Extreme HeatRisk categories mean that health impacts from heat become more likely in general, and may occur in anyone without adequate hydration or cooling. Outside of the Southwest, well-above average temperatures are expected through midweek across much of Intermountain West and Plains states within the warm sector of a developing surface low in the Canadian prairies. While temperatures will not reach the hazardous levels of the Southwest, the warmth combined with strengthening surface winds and dry conditions will support Critical fire weather conditions over the Northern/Central High Plains today and tomorrow, respectively. Widespread Red Flag Warnings are in effect across much of the aforementioned area as of this afternoon. Precipitation-wise, lingering moderate to locally heavy rainfall over the Mid-Atlantic and central Florida should clear out tonight as approaching high-pressure kicks a pesky offshore low to the east. A second batch of showers may arrive to the Eastern U.S. associated with a cold front tomorrow, but rainfall amounts should be modest at best. Otherwise, a weak front in the Gulf of Mexico could support locally heavy rainfall along the Gulf Coast later tomorrow, although much of the heaviest rainfall is forecast to remain offshore. Asherman Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php