Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 317 AM EDT Thu Jun 06 2024 Valid 12Z Thu Jun 06 2024 - 12Z Sat Jun 08 2024 ...Excessive Heat Warnings in effect across the California's Central Valley and much of the Desert Southwest... ...Severe Thunderstorms and Excessive Rainfall possible over portions of the Central Plains and Middle Mississippi Valley on Friday... An entrenched upper-level ridge with embedded shortwave energy will continue to promote a heat wave throughout much of the West through the end of the week. Widespread high and low temperature records are likely to be tied or broken between California Nevada and Arizona today before the heat wave expands north 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 represent 20-30 degree anomalies. 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 warm southerly flow and a couple days of Major to Extreme Heat Risk, particularly over urban parts of the state. 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 this afternoon and 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. 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 into the Middle Mississippi Valley as MCSs that day. The Storm Prediction Center issued a Slight Risk (level 2/5) of Severe Thunderstorms across southwest/south-central Nebraska and northwest/north-central Kansas due to the potential for hail and damaging wind gusts associated with those MCSs. Excessive Rainfall will be more of a concern once those storms move into a more unstable and moist environment in the Lower Missouri Valley Friday evening. Thus, a Slight Risk (at least 15%) of Excessive Rainfall leading to Flash Flooding is in effect for much of eastern Kansas and parts of western Missouri. Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php