FXUS02 KWBC 300800 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 400 AM EDT Mon Mar 30 2026 Valid 12Z Thu Apr 02 2026 - 12Z Mon Apr 06 2026 ...Heavy rain and flooding potential across the central to east- central U.S. late week into the weekend... ...April snow and ice concerns across the Upper Midwest to Great Lakes to Northeast Thursday-Friday... ...Overview... At the start of the period Thursday, a potent shortwave will push a wavy frontal system through the central and eastern U.S. and spread precipitation across the region, including snow and ice in the northern tier and heavy rain farther south. Meanwhile more amplified upper troughing is forecast to move into the Northwest by Thursday and eastward into late week, continuing unsettled weather there, including rain/mountain snow and strong winds. As that trough pushes east into the Plains, additional moisture will be drawn north and renew potential for heavy rain and storms in the Plains/Mississippi Valley and vicinity once again, ending up with multiple days of flooding concerns in that region. The trough and surface front are forecast to gradually push through the eastern U.S. over the weekend, spreading some rain to the Eastern Seaboard around Sunday. ...Guidance/Predictability Assessment... Model guidance has come into somewhat better agreement regarding the timing of the first shortwave moving through the central U.S. and lifting into the Great Lakes Thursday-Friday. This allows for a better consensus in the frontal positions and timing and QPF axis. Although there are still some minor model differences, a multi- model blend worked well for this feature. The model trend over the past couple days has been for the warm front to be farther north across the Ohio Valley eastward. Upstream, the upper low shows good consensus on timing coming into the Northwest Thursday and reaching the Plains Friday, but continues to show increasing model spread by the weekend with its speed tracking east, affecting the associated surface low and trailing cold front. GFS runs continue to be on the fast side, lifting the trough and surface low northeastward more quickly compared to other guidance. Both the AIFS and EC 00Z runs trended a bit slower/westward even compared to their previous runs, so the fast GFS was not favored. The 12Z CMC was among the slowest solutions but the new 00Z run appears to be a good middle ground and is right on top of the AIGFS with the low position at 00Z and 12Z Saturday. The WPC forecast increased proportions of the ensemble means (especially the ECens) and the AIFS as the period progressed given the increasing spread. This model blend also worked with western U.S. ridging behind the trough, though model spread also increases with potential northern stream energy that could reach the West early next week, which will continue to be monitored. ...Weather/Hazards Highlights... A low pressure/frontal system stretching from the Mid-Atlantic across the Ohio Valley and Mid-Mississippi Valley will tap into Gulf moisture and spread rain and thunderstorms to portions of the central and eastern U.S. into Thursday. The moisture and instability along with the upper-level support could lead to flooding concerns across parts of the Middle Mississippi Valley into the Great Lakes region. A Marginal Risk remains in place for Day 4/Thursday in those regions. Convection is likely to the south across parts of Texas into the Lower Mississippi Valley as well, but could be more limited as the forcing lifts out, and higher flash flood guidance could keep the ERO risk less than 5 percent there. A chilly airmass in the northern U.S. will allow for wintry weather concerns in the Great Lakes to Interior Northeast. This includes a swath of freezing rain/ice along with multiple inches of April snow, with the heaviest snow currently forecast in the U.P. of Michigan into northern Maine. Some areas could see transitioning precipitation types throughout the event. Troughing moving through the West Thursday will provide support for precipitation. Lower elevation rain and mountain snow will taper off near the West Coast but overspread the Intermountain West. Several inches of snow with localized totals are over a foot are expected in the northern Rockies. Gusty winds could be a concern across the Intermountain West to Rockies and Plains with this troughy pattern. Precipitation should continue its eastward movement into Friday as the upper trough tracks east, with some snow lingering across the Rockies and potentially spreading across the northern Plains to Upper Midwest. Meanwhile the trough will pull Gulf moisture and instability into the central U.S. once again on Friday. Will start the Day 5/Friday ERO with a Marginal Risk stretching from parts of the southern and central Plains into the Middle Mississippi Valley, with a good setup for high rain rates. The rainfall footprint could be rather similar to a rain event midweek, potentially exacerbating flooding concerns, so will continue to monitor if a Slight Risk may be needed in future issuances. The upper trough and surface low/front should gradually push east over the weekend, bringing precipitation to the east- central U.S. back into the Ark-La-Tex vicinity on Saturday, and across the Eastern Seaboard to Gulf Coast on Sunday. Northern tier ice and snow could be possible once again. Breezy conditions are also possible in the Midwest by the weekend dependent on the low track. Warmer than average temperatures are likely across the south- central to southeastern U.S. through the weekend, with even higher temperature anomalies of generally 15-25 degrees above normal focused over the Ohio Valley as temperatures reach the 70s and 80s there. The Bermuda high will support these above average temperatures while model guidance shows the warm front staying north of these areas. Meanwhile, rounds of cooler than average conditions are likely to move through the north-central U.S. behind cold fronts. Eventually the cold fronts should press across the East into early next week for more seasonable conditions. The West can generally expect near to slightly below average conditions through the latter part of the week, but will warm to above average over the weekend as upper ridging comes in behind the trough aloft. Tate 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 (QPF), excessive rainfall outlook (ERO), winter weather outlook (WWO) probabilities, heat indices, and Key Messages can be accessed from: 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 $$