Significant Winter Storm Analysis, Forecast, and Impacts
I'm sure by now you've heard the news and social media talking about the significant winter storm that is currently impacting the central Plains and will impact the Great Lakes region today into Monday. This blog breaks that down a bit.
WHAT'S GOING ON?
Current radar shows widespread snowfall in place across Kansas and portions of Nebraska and southern Iowa at 9:00am EST. Whiteout conditions, blowing snow, and snowfall rates of up to 2-3" per hour are currently being observed in these locations! Temperatures are in the middle 20s to lower 30s.
WHAT'S CAUSING THIS?
A very strong low pressure system at the surface (which has deepened to 996mb!) is currently in place over southeastern Kansas. More than sufficient atmospheric lifting is in place as a vorticity maximum is swinging through the area in the upper levels of the atmosphere as well. Among other favorable parameters, the atmosphere is nearly completely saturated from the surface to 500mb- this includes the dendritic growth zone (DGZ), where dendrites, or the beginning of snowflakes, develop and grow in size. Lastly, strong cold air advection is wrapping around this low, increasing meltwater (rain to snow) ratios.
HOW MUCH SNOW IS COMING?
A large swath of 8-12" of snow is expected from north-central Kansas through southern Iowa, northern Illinois, and central Michigan by Monday afternoon. There will be an extremely sharp cutoff with snowfall totals, where part of a county may see 12" of snow and another part may see only a few inches. These gradients are extremely difficult to forecast.
CURRENT WATCHES AND WARNINGS
Blizzard Warnings (orange) are in place across much of Kansas, southeastern Nebraska, southern Iowa, and northwestern Missouri. Winter Storm Warnings (pink) are in place across extreme northeastern Missouri, eastern Iowa, northern Illinois, and southern Wisconsin. Winter Weather Advisories (purple) are in place surrounding these warnings, extending into extreme northwestern Indiana and much of Michigan.
- Extremely hazardous or impossible travel
- Whiteout conditions/near-zero visibility
- Blowing and drifting snow
- Quickly accumulating snow
- Rapidly changing conditions
- Winds gusting to 50mph in Blizzard Warning areas
- Winds gusting to 45mph in Winter Storm Warning areas
- Downed tree limbs and power lines possible
- Snowfall rates of up to 2-3" per hour
- Have enough supplies, food, water, and medication for a few days without power
- First aid kit
- If you must travel, bring extra coats, blankets, snacks, flashlights, batteries, etc
- Charge communication devices
- Have multiple ways of receiving emergency notifications
- Your local National Weather Service office website and social media pages