A protracted winter storm with a one-two punch affected Delaware from the early morning of the 26th into the early morning of the 27th. The first phase of the storm affected mainly New Castle County, while the second phase of the storm affected all of the state. Snow and sleet accumulations averaged 1 to 4 inches in Kent and Sussex Counties, 4 to 8 inches in southern New Castle County and 8 to 12 inches in northern New Castle County.
Precipitation began as rain across southern Kent and all of Sussex Counties, sleet in northern Kent County and snow across New Castle County shortly after midnight EST on the 26th. Precipitation in northern Kent County changed to rain by the end of the morning commute, but in New Castle County slowly changed to sleet and then rain during the morning of the 26th. Precipitation became spottier and lighter during the mid day and early afternoon on the 26th. Precipitation in the form of rain increased in intensity across the state during the second half of the afternoon as thunderstorms formed. Precipitation then mixed with or changed to sleet and then to all snow during the early evening. The  snow fell heavy at times during the mid and late evening. The snow ended between 2 a.m. EST and 4 a.m. EST on the 27th.
In Wilmington (New Castle County), a 51-year-old woman pedestrian was killed by a snow plow on the morning of the 27th in the Penny Hill section of the city. Elsewhere in New Castle County, a vehicle skidded into a snow plow on Delaware State Route 1 in Biddles Corner. Delaware State Police responded to nearly 100 accidents and more than two dozen disabled vehicles. There were five injury accidents in Kent County and three roadways blocked by downed trees in Sussex County. Most northern Delaware schools as well as the University of Delaware and State and Senate meetings were closed or canceled on the 27th. The weight of the snow on tree limbs caused about 830 Delmarva Power and Light customers to lose power.
Representative snowfall included 12.1 inches in Hockessin (New Castle County), 11.6 inches in Prices Corner (New Castle County), 10.4 inches at the New Castle County Airport, 8.5 inches in Glasgow (New Castle County), 3.7 inches in Smyrna (Kent County) and Ellendale (Sussex County), 3.4 inches in Dover (Kent County), 2.5 inches in Harrington (Kent County), 1.5 inches in Bridgeville (Sussex County) and 0.7 inches in Lewes (Sussex County).
The latest winter storm was caused by a low pressure system that emerged from the western Gulf of Mexico on the 25th and moved northeast to Cape Hatteras, North Carolina at 7 a.m. EST on the 26th. From there it turned slightly more to the northnortheast and passed through the Delmarva coastal waters during the afternoon and early evening on the 26th and then continued northeast and passed just south of Cape Cod, Massachusetts early on the 27th. The turn more toward the coast permitted some warmer air to reach into Delaware during the day on the 26th. The heavy snow burst was triggered by the surface low's upper air support that passed through the state on the evening of the 26th.

Winter Weather in INLAND SUSSEX, DELAWARE
From 26-JAN-11 20:00:00 to 27-JAN-11 04:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Weather in KENT, DELAWARE
From 26-JAN-11 04:00:00 to 27-JAN-11 03:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Winter Storm in NEW CASTLE, DELAWARE
From 26-JAN-11 04:00:00 to 27-JAN-11 02:00:00 (EST-5)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter