Today offers a nice break from the chilly air from the past couple of days—highs will reach the upper 40s to near 50°F for many, upper 30s along the Canadian border. In fact, Northern New England will see some pockets of light snow showers, with accumulations of a coating to 1” in most areas, and up to 3” in higher elevations.
A powerful winter storm is intensifying as it moves into the Central U.S., bringing widespread hazardous weather through midweek. On the cold side of the system, a swath of heavy snow and strong winds will produce blizzard conditions from the central High Plains into the Upper Midwest. Snowfall totals of 4 to 8 inches are expected, with localized amounts up to a foot by Wednesday. Meanwhile, the warm and unstable sector of the storm will drive an outbreak of severe thunderstorms from the southern Plains into the Lower Mississippi Valley. Several tornadoes, damaging winds, and large hail are possible, particularly from northeast Texas to Mississippi, where an Enhanced Risk (level 3/5) is in place.
Heavy rainfall and the threat of flash flooding will extend from the Midwest into the Southeast, with the heaviest rainfall expected over the Mississippi Valley and portions of the Ohio Valley. By Wednesday, the severe weather threat shifts eastward, impacting the Mid-Atlantic and Southeast with damaging winds and the potential for isolated tornadoes.
Critical to extreme fire weather conditions persist across the Southern High Plains, including New Mexico and western Texas, where strong winds and very dry air will enhance wildfire danger. Further west, a new Pacific storm system arrives in California by Wednesday, bringing heavy rain to the coastal ranges and significant snowfall to the Sierra Nevada.
Temperatures will vary significantly due to the storm system. The Midwest and Eastern U.S. will experience well above-normal warmth, while colder-than-average temperatures expand from the Rockies into the Plains.
After a quiet start to the week, attention turns to an approaching strong storm system that will bring widespread rain, strong winds, and warm temperatures to the Northeast by midweek. High pressure offshore will maintain dry conditions on Tuesday with increasing southerly flow. Temperatures will climb well above normal, with highs in the 40s and 50s across much of the region.
By Tuesday night, light rain begins to spread into the area, particularly across northern New York and Vermont. Temperatures will remain mild, but some sheltered interior valleys may briefly experience freezing rain if temperatures dip near or just below freezing.
The main event unfolds Wednesday into Wednesday night as a deep low-pressure system tracks through the Great Lakes, sending a warm front through the Northeast. Periods of moderate to heavy rain are expected, with rainfall totals of 1.0 to 1.5 inches across much of the region. The heaviest rain is likely to occur Wednesday afternoon and evening. Locally higher amounts are possible in southern Vermont, the Catskills, and western Massachusetts. Some urban and poor drainage flooding is possible in heavier downpours.
Strong southerly winds will also be a concern, particularly Wednesday evening. A low-level jet with winds of 60-70 mph just above the surface could mix down gusts of 40-50 mph, particularly along the south-facing coasts of Long Island, Connecticut, and southeastern Massachusetts. A few isolated thunderstorms cannot be ruled out during the peak of the storm.
By Thursday, a cold front will sweep through, bringing a transition to scattered rain and snow showers across the interior. Colder air will gradually return, but temperatures will remain above average through late week. Gusty northwest winds will develop Thursday night into Friday as colder air settles into the region.
River rises are expected due to the combination of rainfall and snowmelt, particularly across Vermont and northern New York. Ice break-up could lead to localized ice jam flooding on smaller rivers.
