649 FXUS01 KWBC 010458 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 1256 AM EDT Wed Jul 01 2026 Valid 12Z Wed Jul 01 2026 - 12Z Fri Jul 03 2026 ...Dangerous heat to build across the central and eastern U.S.; below normal temperatures for the West... ...Isolated to scattered severe weather and heavy rain continue across the Central U.S. and Northeast through Friday... ...Critical fire weather conditions expected over the Four Corners through tomorrow... A highly amplified upper-level ridge over central and eastern U.S. will bring a dangerous heatwave through the weekend. Highs will reach the mid to upper 90s, with numerous locations exceeding 100 degrees. Many areas across the Ohio Valley, Mid-Atlantic into the Northeast will see record breaking highs through Thursday. Combined with dewpoints remaining well into the 70s, peak heat indices are expected to reach 100 to 115 degrees across portions of lower Mississippi Valley into the Northeast. The combination of daytime heat and little overnight relief (as lows are expected to drop to the 70s-80s), will lead to widespread areas of Major to Extreme HeatRisk from the Midwest to the East Coast. This will pose a risk for heat-related illnesses, especially for vulnerable populations and those without adequate cooling. Across the West, a longwave trough will maintain temperatures generally 5 to 15 degrees below average. Otherwise, a upper-level trough remains anchored across the western CONUS, maintaining a cyclonic flow and periodically ejecting shortwave energy northeastward into the Northern Plains. Additionally, a frontal boundary draping across Upper Midwest into the Great Lakes and surface troughs will remain the focus for multiple rounds of showers and thunderstorms along the boundary through Wednesday. The combination of mid to upper level forcing and moist southwesterly flow will support excessive rainfall and severe thunderstorms across the Upper Midwest and Great Lakes region. A surface trough will extend across the Northeast into parts of the Mid-Atlantic, expanding the risk for excessive rainfall and severe thunderstorms across parts of the Northeast as clusters of thunderstorms may develop during the evening/overnight hours on Wednesday. Another frontal boundary will drop from southern Canada on Thursday, reinforcing showers and thunderstorms across the northern tier. Strong instability and sufficient moisture may support multiple rounds of organized convection, which can produce widespread damaging wind gusts, large hail, and excessive rainfall across the Northern Plains into parts of the Great Lakes and Northeast. Further south, daily rounds of scattered to numerous thunderstorms will continue across the Gulf Coast, Southeast, and Florida, as a deep tropical moisture and unstable airmass remains in place. Slow-moving storms will be capable of producing high rainfall rates, which can bring isolated flash flooding. Over the portions of the southern/central Plains, repeated convection may develop along the surface trough where southerly flow will maintain moisture convergence, bringing a risk for isolated flash flooding and excessive rainfall on Wednesday. Over the Four Corners, fire conditions continue as strong south/southwesterly winds and dry airmass brings Critical fire weather concerns on Wednesday. Oudit Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$