Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 400 PM EDT Thu Jul 04 2024 Valid 00Z Fri Jul 05 2024 - 00Z Sun Jul 07 2024 ...Heat is expected to intensify and spread further up the West Coast much of the West through this weekend with record-breaking temperatures... ...Oppressive heat and humidity across the South today will shift east into the Mid-Atlantic and Southeast Friday and Saturday... ...Flash flooding and severe thunderstorms possible over parts of the Midwest, and from the Southern Plains to the Ohio Valley through tonight... ...Beryl is forecast to re-intensify over the southwestern Gulf of Mexico on Saturday and threaten southern Texas... On this 4th of July, a significant and increasingly dangerous heatwave is set to intensify along the West Coast as we head into the extended holiday weekend. Widespread high temperatures well up into the 100s and 110s this afternoon across the lower elevations in California will soar even higher by Friday afternoon. Saturday will likely shape up to be the hottest day in this heatwave when high temperatures into the 110s will be common across California outside of the cooling effects of the Pacific Ocean near the coast and the naturally cooler higher elevations. Numerous record-breaking temperatures can be expected through the next few days. Locally higher temperatures into the 120s are possible in the typical hot spots of the Desert Southwest. The triple-digit heat will expand northward into the Pacific Northwest and parts of the central Great Basin, with widespread highs rising into the 90s and low 100s. The duration of this heat is also concerning as scorching above average temperatures are forecast to linger into next week. Heat impacts can compound over time, therefore it is important to remain weather aware and follow the advice of local officials. This level of heat throughout parts of the Mojave Desert and Sacramento/San Joaquin valleys of California could pose a risk to anyone if proper heat safety is not followed. It is imperative to stay hydrated, out of direct sunlight, and in buildings with sufficient air-conditioning when possible. It is also equally as important to check on the safety of vulnerable friends, family, and neighbors. Meanwhile, oppressive heat and humidity across the southern Plains and lower Mississippi Valley today will begin to shift eastward to the Mid-Atlantic and Southeast for the end of the week. High temperatures rising into the upper 90s and low 100s are expected, with heat indices soaring into the 110s across the lower Mississippi Valley. Warm overnight conditions in the upper 70s and low 80s will offer little relief, leading to a dangerous situation for those without access to adequate cooling. A cold front entering the southern Plains is anticipated to offer cooler and below average temperatures to Oklahoma, much of northern/western Texas, and the Mid-South by Friday. Above average temperatures are then anticipated to confine to the Southeast and Mid-Atlantic for the start of the weekend, with afternoon highs into the mid-to-upper 90s. If planning to spend an extended amount of time outdoors this Fourth of July, be sure to use caution and act quickly if you see signs of heat-related illnesses. An active and stormy weather pattern over the central U.S. is expected to bring heightened chances for severe thunderstorms and heavy rainfall, which could impact holiday gatherings through early this weekend. A developing area of low pressure over the northern Plains is forecast to progress into the upper Midwest by tonight and team up with a lingering frontal boundary stretching from the lower Great Lakes to the southern Plains to trigger some meteorological fireworks. Thunderstorm chances span from the southern Plains/Rockies to the middle/upper Mississippi Valley and also eastward to the Ohio Valley and Mid-Atlantic. However, the greatest threat for strong to severe thunderstorms will be near/along the frontal boundary through parts of the middle/upper Mississippi Valley and southern Plains. Damaging wind gusts and frequent lightning are the most likely weather hazard associated with these Fourth of July storms. Flash flooding will remain a concern throughout the upper Midwest as well due to yet another round of thunderstorms overlapping areas dealing with ongoing river flooding and saturated soils, with scattered flash flooding also possible between the Ohio Valley and southern Plains. On Friday, thunderstorms will continue to progress eastward with the frontal boundary into much of the eastern third of the country. Isolated strong to severe storms and flash flooding are possible. The greatest threat for damaging wind gusts associated with these storms will be across the upper Ohio Valley. Elsewhere, daily thunderstorm chances associated with daytime heating are possible along the Gulf Coast and Florida. Scattered showers and thunderstorms are also possible throughout the north-central U.S. this weekend as upper troughing remains over the region. Residents and visitors located within areas expecting severe weather and/or heavy rainfall are advised to remain weather aware, have multiple ways to receive warnings, and never drive across flooded roadways. As we head into the weekend, interests along the western Gulf of Mexico should pay attention to the future progress of Hurricane Beryl, currently located in the western Caribbean Sea. Beryl is forecast to weaken into a tropical storm as it traverses the Yucatan Peninsula on Friday before emerging into the southwestern Gulf of Mexico on Saturday. Beryl has an opportunity to re-intensify over the Gulf and turn more northwest toward the southern tip of Texas by the end of this forecast period Saturday evening. Have a safe Independence Day! Kong/Snell Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php