892 FOUS30 KWBC 301550 QPFERD Excessive Rainfall Discussion NWS Weather Prediction Center College Park MD 1150 AM EDT Mon Mar 30 2026 Day 1 Valid 16Z Mon Mar 30 2026 - 12Z Tue Mar 31 2026 The probability of rainfall exceeding flash flood guidance is less than 5 percent. General pattern will induce areas of moderate to locally heavy rainfall across MI to areas downwind of Lake Erie and Ontario. Guidance has trended north from the previous runs leaving an axis of higher QPF more likely off Ontario with increasing convergent flow mainly north of I-90 beginning later this afternoon through the overnight. CAMs are in relatively good agreement on an area of 0.75-1.5" of rainfall across areas of western NY state with neighborhood probabilities of >1" running between 60-90% over the entire area from the NY/PA border off Lake Erie to off the southern portion of Lake Ontario. The key in this setup is the lack of sufficient buoyancy with rates being capped below 1"/hr as prob fields indicate <1% chance of rates exceeding the threshold. Urbanized zones will have a non-zero potential across eastern MI near and over Detroit proper and any larger urbanized zones in western NY. First guess fields remain un-enthused for this particular period as well with a nil remaining over the aforementioned areas. Will hold off on any introductions of a risk area, but will reiterate that the setup is non-zero, but the risk is below standard thresholds. Kleebauer Day 2 Valid 12Z Tue Mar 31 2026 - 12Z Wed Apr 01 2026 ...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF THE GREAT LAKES INTO NORTHERN NEW ENGLAND... The latest guidance has continued to see an uptick in forecast amounts across the lower Great lakes and New England regions for this period. Impressive moisture advection characterized by IVT values exceeding 750 kg/ms in spots will move northeast along a slow-moving front across the Great Lakes. This will allow near record amounts of atmospheric moisture for this time of year, with PWATs exceeding 1.25 inches at times to move into the Marginal Risk area. Instability will increase towards the south and west, but drier antecedent soil conditions and weaker forcing should cancel out those supporting meteorological factors along the Mississippi River and the Ozarks. During this period a stationary front draped across New York remain in place, providing focus for rounds of scattered convection to fire up. By Tuesday evening rainfall coverage should increase as an area of low pressure tracks along the frontal boundary. Guidance continues to favor areal averages of 1-2 inches for the region, however with training possible, localized higher amounts of 2-4 inches may materialize over the northeast Ohio, far northwest PA and into southwest NY...near the stationary front and within a corridor where instability has a better chance of persisting. Campbell/Chenard Day 3 Valid 12Z Wed Apr 01 2026 - 12Z Thu Apr 02 2026 ...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL STRETCHING FROM TEXAS TO THE MIDWEST/UPPER MIDWEST... The central portion of the country is shaping up for heavy rainfall as a frontal system extending from the Northeast to the Mid-South taps into Gulf moisture advecting northward. Multiple rounds of convection are expected to fire up across central and eastern CONUS given the upper level support for sustained rainfall potential. Local flooding may arise over portions of the Southern Plains, Lower and Mid-Mississippi Valley. The general footprint of the rainfall shield has trended a bit west from the previous cycle thus requiring a western adjustment of the Marginal Risk area. Consensus continues to favor the highest QPF to focus over eastern Oklahoma, southeast Kansas and into central Missouri. The timing of the incoming shortwave/lifting warm front has remained a trickier part of the forecast, and convection south along the cold front may also limit instability further north/become the higher threat. At this time a Slight Risk was not raised but may be needed with future updates. Campbell/Tate Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt