A surface low deepened as it moved yesterday from the central Plains to the Great Lakes by Tuesday morning. A band of around 1/2 foot of snowfall resulted, extending from eastern Wyoming, western South Dakota, and western Nebraska through the Michigan Upper Peninsula. Up to 1 foot of snowfall was reported in northeastern Wisconsin. A rain/snow mix was present from central Nebraska through central and northeastern Wisconsin, with heavy rainfall of 1 to 2 inches farther south. Farther west, 1/2 to 1 foot of snowfall was observed in the northern Rockies through the northern Great Basin. In the East, disturbed weather associated with a warm front to the east of the central U.S. low brought up to 1/2 foot of snowfall to the Northeast.
Moderate snowmelt occurred in the rain/snow mix areas across the Plains and Midwest, from southwestern Nebraska through central Wisconsin and central lower Michigan. Ahead of the warm front in the Northeast, air temperatures in the 40s and 50s and moderate rainfall caused moderate to rapid snowmelt through southern New York and at lower elevations and near the coast. Recent snowfall and cooler air temperatures in the West have cooled the snowpack there.
A surface low is over Lake Huron this morning, and as the low continues to deepen, it will continue moving northeastward into eastern Canada. Around 1/2 foot of snowfall is possible in the northern Great Lakes and in the far Northeast today with the surface low; most of the heavy snowfall will be in southeastern Canada north of the warm front and with the surface low. Little precipitation in the coterminous U.S. is expected on Wednesday with this storm. Cool high surface pressure will move eastward from the Midwest during midweek.
A potent midlevel disturbance will undercut a strong eastern Pacific ridge Wednesday and Thursday. The lack of low-level support for this feature will allow only light snowfall to occur across the central Sierra Nevada tomorrow and the Great Basin and central and southern Rockies late tomorrow through Thursday. Amounts are expected to be around 1/2 foot, with around 1/2 inch of rainfall possible at lower levels.
weather.gov
