Significant winter storm to affect eastern Iowa starting Tuesday

CEDAR RAPIDS, Iowa (KCRG) - A storm system that will bring a variety of significant weather impacts to eastern Iowa will move into the region on Tuesday, potentially snarling travel and dropping several inches of snow.

People in the KCRG-TV9 viewing area should prepare for disruptions to travel and other activities from Tuesday afternoon through early Wednesday. Numerous weather-related delays, closings, and cancelations will likely be posted over the next several days; updates to those can be found here.

STORM TIMING: Precipitation will develop in the Plains and move to the northeast. Due to cold air in place across eastern Iowa at the storm’s onset, snow will be the primary precipitation type as it begins in the southwest corner of the viewing area toward Ottumwa at around Noon. Over the next few hours, snow reaches the northeast corner of the viewing area by around 4 p.m. The Cedar Rapids-Iowa City corridor will likely start to see snow and related impacts between about 2:00 and 3:00 p.m.

Snow continues north of Highway 30 for the majority of the night on Tuesday night. Toward the Highway 30 corridor and points to the south, a mix of snow, freezing rain, and sleet will be possible as warmer air gets drawn into the storm system.

Precipitation ends by late morning or early afternoon on Wednesday. Winds will remain somewhat strong on Wednesday afternoon as the system moves away.

STORM IMPACTS: Snow will be moderate to heavy at times, which will lead to quickly-deteriorating road conditions across all of eastern Iowa. Due to the potentially-intense snowfall rates, expect road conditions to become poor within an hour of the snow’s onset at your particular location. This, combined with the afternoon timing of the start of snow, will cause difficult travel during the time period that people travel home from work. Plan on a longer commute.

Areas near the transition from snow to mixed precipitation could see some minor ice accumulations, which could lead to some tree limbs damaged or isolated power outages during periods of particularly strong winds. Those gusts could be strongest during the overnight period Tuesday night into Wednesday morning, or Wednesday afternoon as the system exits.

SNOW AMOUNTS: A broad area of 4 to 8 inches of snow is likely, generally north of Interstate 80 in the TV9 viewing area. Lesser snowfall totals of 2 to 4 inches will be found south of that area, but there could also be ice accumulations of up to 0.10″ in that area as precipitation becomes mixed. Some ice accumulation is possible as far north as the Highway 30 corridor, but the biggest impact will be from snowfall in that area.

The area of the highest uncertainty in snowfall totals will be in the zone that could experience mixed precipitation, which is generally south of Highway 30. A longer period of a mix of sleet and freezing rain there could lead to lower snowfall totals, but travel would still experience significant disruptions.

AFTER THE STORM: First and foremost, if you are in an area that experiences heavy snowfall, particularly if the snow itself is of a wet and heavy composition, do not overdo it when clearing your sidewalks and driveways. This is especially true for people who have cardiac conditions, which can be exacerbated by overexertion when trying to lift the heavy snow. Take breaks and don’t try to clear an entire section of snow all at once.

The forecast for the remainder of the week turns colder with highs generally in the 20s. Another storm system approaches the area on Friday. We will be watching the track of this storm and its potential impacts, which could affect the TV9 viewing area with some more snow.

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