Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
871 FXUS02 KWBC 021916 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 316 PM EDT Tue Jun 2 2026 Valid 12Z Fri Jun 05 2026 - 12Z Tue Jun 09 2026 ...Guidance/Predictability Assessment... Guidance solutions seem reasonably well clustered Friday/Saturday and a GFS/ECMWF/UKMET/Canadian model blend seems well supported by multi-model ensembles. Guidance becomes more varied with potential return toward amplifying/blocky flow over the lower 48/vicinity into next week. The ECMWF in this vein offers more eastward translating flow over the nation, but was marginally discounted given overall trends toward amplification. A composite blend of the GFS/Canadian models and ensemble means was prioritized for now. ...Weather/Hazards Highlights... A wavy and slow moving front sliding southward from the northern tier of the lower 48 will bring showers/thunderstorms to portions of the Upper Midwest, Great Lakes, Northeast, and eventually Ohio Valley/Mid-Atlantic. Convection Friday could produce isolated instances of flash flooding over portions of the Middle to Upper Mississippi Valley, which is supported by a WPC Excessive Rainfall Outlook (ERO) Marginal Risk area that shifts over the Midwest for Saturday. Showers/thunderstorms shift into the Ohio Valley/Great Lakes Saturday before finally spreading into the Northeast/Mid- Atlantic Sunday, where there`s potential for heavy downpours. Associated upper trough/low amplification and blocky nature could protract post-frontal cooling and lead heavy downpour threats early next week down through the Mid-Atlantic toward the Southeast, albeit with much uncertainty with shift/focus. Mid-upper level shortwaves gliding slowly northward out of Mexico into the south-central U.S. will be responsible for multiple rounds of heavy convection spreading from the Southern Plains late week/weekend and into the Lower Mississippi Valley this weekend/early next week. WPC ERO Day 4/Friday and Day 5/Saturday Marginal Risk areas are in place with favorable flow, instability and protracted inflow/moisture to fuel repeat activity to monitor. Amplified troughing will generate rainfall across the Pacific Northwest on Friday/Saturday, then spreading into the Northern Plains and Upper Midwest Sunday and Monday. Uncertain subsequent system energies and renewed rain chances in amplifying flow may prove slow to reach the Pacific Northwest/West Coast next week. Kebede/Schichtel Additional 3-7 Day Hazard information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation forecast, excessive rainfall outlook, winter weather outlook probabilities, heat indices and Key Messages are at: https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml https://www.wpc.ncep.noaa.gov/#page=ero https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml https://www.wpc.ncep.noaa.gov/#page=ovw $$