092 FXUS02 KWBC 271913 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 313 PM EDT Wed May 27 2026 Valid 12Z Sat May 30 2026 - 12Z Wed Jun 03 2026 ...Heavy Rain/Thunderstorm Threats for the South/Southeast U.S. and the Northern Rockies states for this Weekend... ...Overview... A blocky upper flow pattern will be in place to start the period Saturday featuring troughing over both the West and East, with ridging in between over the Central U.S.. The trough over the West will weaken as it lifts northeastward bringing heavy rain potential to parts of the northern Rockies/High Plains this weekend. Another shortwave will move into the Pacific Northwest early next week. Troughing over the East will be reinforced through the period, with a frontal boundary draped across the southern edge of it across the South/Southeast. This, combined with forcing from southern stream energy in the region and an increasingly favorable deep moisture influx/slow system translations, will allow for a generally continued wet pattern across much of the South/Southeast where things have been very wet as of late, and will continue to be in the short range period as well. ...Guidance/Predictability Assessment... Guidance solution clustering has improved for the weekend into Monday, bolstering forecast confidence. Guidance for the most part shows good agreement on the overall sluggish large scale pattern evolution through the period, but still with plenty of variability in the smaller scale details next week. Out West, the guidance shows reasonable consensus with the upper low/trough lifting northeastward out of the Great Basin by the weekend, but a lot of uncertainty on subsequent energies into the overall trough. Overall though, the pattern should become less amplified over this region with time. In the East, there remains lots of uncertainty still with a variety of shortwaves as they drop down the western side of the trough to reinforce and deepen mean troughing over the East. There is some indication is guidance for a possible cut off low over the East by the middle of next week, but plenty of run to run variability on this evolution to buy into any one solution at this point. For the most part, a blend of the models and ensemble means seemed to provide a solid forecast basis that seems to mitigate differences as consistent with individual predictability. This solution is generally in line with the NBM and WPC product continuity and fits National Hurricane Center insight that continues to discount tropical moisture feed and development potential by recent GFS runs northward out from the Caribbean. ...Weather/Hazards Highlights... Persistent shortwave energies and a couple of wavy frontal boundaries will continue to keep much of the South active and unsettled into the weekend within a moist and unstable environment and daily thunderstorm chances. Combined with what has already been a wet pattern across this region, isolated flooding could be a concern. For Day 4/Saturday and Day 5/Sunday, marginal risk areas have been introduced for parts of the Southeast near a wavy the frontal boundary. There is also an increasing signal for heavy rainfall for Florida to monitor extending well into next week. Over the Northeast, a vigorous upper troughing working through this weekend may result in a period of moderate to heavier rainfall for parts of New England given windy offshore coastal low genesis. Out West...upper troughing lifting out of the Great Basin with a wavy frontal system ahead of it will allow for increased precipitation across the Intermountain West lingering into the weekend. Snow is possible across the highest elevations, though with minimal accumulation. The signal for heavy rainfall has increased over parts of the northern Rockies states so Marginal Risk areas have been introduced for Day 4/Saturday and Day 5/Sunday EROs. Rainfall chances also increase this weekend and into next week for parts of the northern and central Plains ahead of areas of upper troughing lingering over the West. With the closed upper low over the West during the short range working to lift out by this weekend, below normal temperatures should moderate back towards normal. Some ridging building back into the region late in the period may bring temperatures above average by then. The upper ridge to its east will allow for warmer than average temperatures across the north- central U.S. through much of next week, with daytime highs 10-20 degrees above normal, with greatest anomalies early in the period. Persistent troughing over the East will bring slightly below normal temperatures. Santorelli/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 $$