Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 321 PM EDT Thu May 01 2025 Valid 00Z Fri May 02 2025 - 00Z Sun May 04 2025 ...A mid to upper level omega block to form across the CONUS, leading to active weather and large temperatures contrasts... ...Heavy rain, flooding and severe weather threats to stretch from the Southern Plains, northeast into Ohio Valley and eastern Lakes region... The mid to upper level flow pattern will become increasingly blocked over the next few days with an omega block forming from California, eastward into the Ohio Valley. The eastern component of this block will be comprised of a slow moving and strengthening closed low forming across the Lower Missouri Valley Friday and moving into the Mid Mississippi Valley/Lower Ohio Valley region on Saturday. To the west of this, an amplified upper ridge will stretch across the Great Basin/Rockies region Friday/Saturday and move into the High Plains late Saturday into Sunday. Meanwhile, the western component of the omega block will see a strong closed low form along the northern California coast Saturday and drop south into Southern California into early Sunday. An axis of above average moisture values expected to persist along and to the east of a frontal zone that will be moving only slowly eastward over the next few days, associated with the eastern component of the omega block. This will support increasingly active showers and thunderstorms over a large portion of the CONUS from the Southern Plains, into the Lower Mississippi Valley, Tennessee Valley, Ohio Valley and eastern Lakes region. This active shower and thunderstorm pattern over the next two days will be falling across areas that have seen above average precipitation over the past month, which has resulted in high soil moisture and stream flow values. This additional rains over the more saturated soils and higher stream flow will support a risk of flooding from enhanced runoff across these areas. In addition to the flooding threat, the active shower and thunderstorm pattern will support potential for severe weather over the next two days from the Southern Plains, into the Lower Mississippi Valley, Tennessee Valley, Ohio Valley and eastern Lakes region. Large hail and damaging winds will be the greatest severe weather risks across these areas, with tornadoes a lesser risk. The expected heavy rains over the next few two days, will remain to the west of the immediate eastern seaboard that continues to be dry and experience widespread moderate to severe drought conditions. However, portions of the drought area along the east coast will have the potential for much needed rains late this weekend into early next week, bringing at least some relief to the current drought conditions. With the above mentioned highly amplified systems stretching west to east across the CONUS, large temperatures contrasts will develop. Below average temperatures expected to develop on Saturday along all of the West coast from Washington to California, pushing into the Southwest and becoming much below average (15 to 25 degree below average) by the end of the weekend as the strong closed low forms. Underneath the amplified upper ridge to the east and northeast of this, much above average temperatures across the Northern Great Basin/Northern Rockies Friday will push east into the Northern to Central Plains by this weekend. Meanwhile, below average temperatures expected in the above mentioned region of active precipitation stretching from the Southern Plains into the Lower to Mid Mississippi Valley, Ohio Valley, Tennessee Valley and eastern Lakes regions. While all of these regions see large temperature contrasts and large negative an positive temperatures anomalies, there is not expected to be any widespread record, warm or cold over the next few days. Oravec Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php