Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 402 AM EDT Thu Jun 09 2022 Valid 12Z Thu Jun 09 2022 - 12Z Sat Jun 11 2022 ...There is a Slight Risk of severe thunderstorms and excessive rainfall over parts of the Central/Southern Plains through Friday morning... ...There is a Slight Risk of excessive rainfall over parts of the Mid-Atlantic/Central Appalachians and a second area over parts of the Tennessee Valley/Southeast through Thursday morning... ...There is a Slight Risk of severe thunderstorms and excessive rainfall over parts of the Lower Mississippi/Tennessee Valleys/Central Gulf Coast from Friday into Saturday morning... ...Excessive heat over parts of Central/Southern California and the Southwest on Friday and Saturday as record high temperatures persist over southeastern Texas... A front extending from the New England Coast to a wave of low pressure over the Lower Great Lakes/Central Appalachians will move eastward off most of the Eastern Seaboard by late Thursday night. Rain with embedded thunderstorms will develop along and ahead of the boundary from the Northeast. Showers and thunderstorms develop along and ahead of the boundary from the Mid-Atlantic to the Southeast and the Gulf Coast through Friday morning. There will be a Marginal Risk of severe thunderstorms along the front through Friday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and minimal risk of tornadoes. In addition, a wave of low pressure over the Central High Plains on Thursday will move southeastward to the Southeast by Saturday. As a result, showers and thunderstorms will develop along and ahead of the associated warm front over parts of the Central/Southern Plains on Thursday and into parts of the Lower Mississippi Valley/Central Gulf Coast by Friday. Some of the thunderstorms will be severe. Therefore, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Central/Southern Plains through Friday morning. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. There will also be an increased risk of hail two inches or greater and severe thunderstorm wind gusts 65 knots or greater over the region. There will also be heavy rain associated with these thunderstorms. Therefore, the WPC has issued a Slight Risk of excessive rainfall over parts of the Central/Southern Plains and Lower Mississippi Valley through Friday morning. The associated heavy rain will create mainly localized areas of flash flooding, with urban areas, roads, and small streams the most vulnerable. On Friday, the threat of severe thunderstorms moves southeastward over the Lower Mississippi/Tennessee Valleys/Central Gulf Coast from Friday into Saturday morning on Friday. Showers and thunderstorms will develop ahead of the boundary to the Mississippi Valley. Therefore, from Friday into Saturday morning, the SPC has issued a Slight Risk of severe thunderstorms over parts of the Lower Mississippi/Tennessee Valleys/Central Gulf Coast. The hazards associated with these thunderstorms are frequent lightning, severe thunderstorm wind gusts, hail, and a few tornadoes. Moreover, there will be some heavy rain associated with these thunderstorms. Therefore, the WPC has issued a Marginal Risk of excessive rainfall over parts of the Lower Mississippi and Tennessee Valleys from Friday into Saturday morning. The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain. Furthermore, upper-level energy will aid in producing rain over parts of the Ohio Valley/Central Appalachians overnight Friday and into the Mid-Atlantic on Saturday. Meanwhile, on Thursday, a boundary will move onshore over the Pacific Northwest and move inland to the Northern Plains by Saturday. The system will produce light rain over the Pacific Northwest by Thursday afternoon. Strong onshore flow will aid in producing moderate to heavy rain over parts of the Northwest on Thursday. Therefore, the WPC has issued a Marginal Risk of excessive rainfall over parts of the Pacific Northwest through Friday morning. The associated heavy rain will create localized areas of flash flooding, affecting areas that experience rapid runoff with heavy rain and burn scars. The onshore flow continues into Saturday. Rain will move into parts of the Northern Intermountain Region on Thursday evening through Saturday. Moderate to heavy rain will also be associated with these areas. Therefore, the WPC has issued a Marginal Risk of excessive rainfall over parts of the Pacific Northwest and the Northern Intermountain Region Friday through Saturday morning. Furthermore, upper-level ridging will expand westward over California by Friday. Upper-level ridging and dry soils will combine to allow high temperatures in the upper 90s and 100s for much of Central/Southern California and the Southwest. Little respite overnight as low temperatures are also expected to tie or break records across much of the region on Thursday and Friday nights. Therefore, excessive Heat Warnings are in effect for much of the Southwest. Additionally, excessive Heat Watches/Advisories affect much of Central California and parts of western Nevada. Records in southeast Texas continue to be threatened through the weekend as high temperatures remain in the low 100s. Ziegenfelder Graphics are available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php