Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 300 PM EST Tue Feb 11 2025 Valid 00Z Wed Feb 12 2025 - 00Z Fri Feb 14 2025 ...Winter storm to impact the Mid-Atlantic states through tonight with areas of locally heavy snow, sleet and freezing rain... ...New winter storm with heavy snow and some ice to organize over the central Plains and Midwest by Wednesday before impacting the Great Lakes and Northeast through Thursday... ...Heavy rainfall and thunderstorms will bring concerns for flash flooding and severe weather to portions of the Gulf Coast states, Mid-South and Southeast going through early Thursday... ...Atmospheric river to bring heavy rainfall and flooding concerns to California as heavy snowfall arrives over the Sierra Nevada... A very active weather pattern is expected across the nation over the next couple of days as multiple winter storms impact the central and eastern parts of the country while a new atmospheric river arrives across the West Coast and brings significant impacts to California. Initially, a swath of locally heavy snow and icing from sleet and freezing rain will impact the Mid-Atlantic states tonight into the early morning hours of Wednesday as a continuation of Gulf moisture lifting northeastward along with the advance of low pressure near the East Coast occurs. Several inches of additional snow accumulation will be possible along with up to a 0.25" to 0.50" of ice accumulation locally. Dangerous travel conditions are expected along with some potential for tree damage and power outages due to the snow and ice. This initial system will move out to sea early Wednesday, but as this occurs, there will be a new winter storm organizing across the central Plains and Midwest which will yield a swath of heavy accumulating snow and a narrow axis of ice. This storm system will strengthen Wednesday night as it impacts the Great Lakes region and then moves into the Northeast on Thursday. As much as 4 to 8+ inches of snow is expected from central Kansas northeastward through Lower Michigan and also up across northern New England. This storm will also foster hazardous travel conditions. Farther south across the Gulf Coast states and Mid-South, a combination of both of these storms systems will bring a threat for multiple rounds of heavy rainfall and thunderstorms which is expected to bring concerns for flash flooding and severe weather. The Weather Prediction Center has depicted a Slight Risk (level 2 of 4) of excessive rainfall from eastern Texas northeastward into central Mississippi going through tonight, and then separately across the Mid-South and Southeast Wednesday through early Thursday. Severe weather including a threat for strong winds and potentially tornadoes will exist across especially the central Gulf Coast region, and the Storm Prediction Center has depicted a Slight Risk (level 2 of 5) of severe weather across this area. All of the heavy rainfall and severe weather hazards should begin to diminish on Thursday as a cold front sweeps across the region. Meanwhile, a new atmospheric river will be crossing the West Coast and impacting California by especially Wednesday night and Thursday. Heavy rainfall is expected across the coastal ranges of especially central and southern California along with the Central Valley and the upslope areas of the Sierra Nevada foothills. Flooding is expected be a notable concern, and portions of southern California near the Los Angeles Basin and adjacent coastal terrain that recently experienced wildfire activity will be at risk for seeing dangerous flash flooding and debris flow activity. The Weather Prediction Center has depicted a Moderate Risk (level 3 of 4) of excessive rainfall across this very sensitive area of southern California where burn scars are noted. A Slight Risk of excessive rainfall is focused farther north up across much of central California. Just off to the east into the higher terrain of the Sierra Nevada, very heavy snowfall is expected, and locally as much as 2 to 4 feet of new snowfall is expected through Thursday. Orrison Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php