Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Thu Jun 06 2024 Valid 00Z Fri Jun 07 2024 - 00Z Sun Jun 09 2024 ...Excessive Heat Warnings remain in effect across the California's Central Valley and much of the Desert Southwest... ...A couple rounds of severe thunderstorms and heavy rainfall possible across portions of the Central Plains toward the Mid-Mississippi Valley Friday and Saturday... A strong upper-level ridge associated with the ongoing heat wave over the Southwest is forecast to reach its peak intensity today (Thursday) before sliding off slowly toward the southern Plains during the next couple of days. Widespread high and low temperature records being tied or broken between California Nevada and Arizona today will expand a bit northward into Oregon and Washington on Friday and Saturday. Highs in the 90s and 100s followed by lows ranging from the upper 50s to mid 70s will lower by a couple of degrees each day. HeatRisk will peak between Major and Extreme today for much of the West, with California's Central Valley and the Desert Southwest being of particular concern due to their lower elevations and some urban areas. Little to no overnight relief from the heat will affect those without effective cooling and/or adequate hydration. Mid-level energy propagating through the Florida peninsula will support scattered thunderstorms that may become severe this evening. Meanwhile, a couple days of Major to Extreme Heat Risk, particularly over urban areas are forecast for the southern half of the peninsula. Several high and low temperature records may be tied or broken on Friday and Saturday. Showers and thunderstorms will develop along a cold front moving across the East Coast today. Locally heavy rainfall may occur over portions of the Interior Northeast and southern New England into the evening. Things mostly clear out across the East Coast on Friday, save for parts of northern/central New England where some light showers and an isolated thunderstorm will be possible. A lingering upper-level low will keep temperatures cooler than normal across the northern tier states along with windy conditions into the weekend. The associated instability will also support occasional showers across the Great Lakes for the next couple of days. We shift our attention to the Central U.S. on Friday as a low pressure system emerges from the Rockies. Showers and thunderstorms are expected to develop across the Central Plains and move generally east toward the Mid-Mississippi Valley as organized clusters of thunderstorms that day. The Storm Prediction Center issued a Slight Risk (level 2/5) of Severe Thunderstorms across south-central Nebraska into northern Kansas due to the potential of damaging wind gusts and some hail. Excessive Rainfall will be more likely farther downstream from eastern Kansas into western Missouri. By Saturday, the thunderstorms and heavy rain are expected to push farther southeast toward the mid-Mississippi Valley when colder air from the northern Plains begins to edge southward. The best chance for these storms to develop will be from Friday afternoon into the evening from eastern Oklahoma to northern Arkansas and southern Missouri. Kong/Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php