Peoria, Ill. (WMBD) — A storm system brought much of Central Illinois 1-3 Inches of rainfall Tuesday night and Wednesday and resulted in a few daily rainfall records being broken. While the weather is expected to remain relatively quiet this weekend, another strong storm is expected to swing through Illinois Sunday night and Monday bringing periods of heavy rain and strong winds to the region.

Key Takeaways

  • Rain & storms develop Sunday evening, wraps up Monday afternoon
  • Rainfall amounts over 1.0″ likely west of I-55
  • Wind gusts of 40-50 mph possible Monday
  • Rising rivers to lead to growing concern of flooding

A strong storm system working its way south along the west coast is set to bring heavy snow and rain to southern California. The National Weather Service in Los Angeles issued it’s first Blizzard Warning since 1989 for the mountains in Los Angeles County where over 5 feet of snow and 75 mph wind gusts are expected through Saturday.

Sunday Night Through Monday

That same system is expected to quickly race inland over the Great Basin and the central Rockies on Sunday, arriving in the Midwest on Monday. Model guidance suggest that a strengthening area of low pressure will pass through eastern Iowa and northwest Illinois Monday afternoon. The central pressure of the system could be near 980 mb which is in record territory for a low pressure system moving through our area this time of year.

The track of the storm will keep the precipitation type in the form of rain with temperatures in the 40’s at night and 50’s during the day. Rain is expected to start Sunday evening with periods of heavy rain and thunderstorms possible overnight. Rain will continue into Monday but should come to an end from south to north in the afternoon. The storm won’t have the same amount of moisture that our last storm did, but much of Central Illinois could still see more than an inch of rain.

As of now the timing of the system doesn’t favor the development of severe storms locally, but that could change over the next couple of days. Of greater concern could be strong gradient winds associated with the abnormally deep area of low pressure. Southerly wind gusts between 40-50 mph are expected and could present a blow over risk to high profile vehicles along I-74. Given already saturated soils, the strong winds could lead to a greater risk of shallow rooted trees being blown over as well.

Short Term Flood Outlook

In the wake of Wednesday’s rain, river levels across Central Illinois are on the rise. A Flood Warning has been issued for the Illinois River near La Salle Peru which is expected to see the river level climb reach minor flood stage (20 feet) on Saturday. Water levels are expected to also rise further down stream in Henry and Peoria but the river should remain below flood stage. As for the Illinois River at Havana, the river is expected to climb above flood stage around the middle of next week. The amount of rain we receive Sunday night and Monday could determine whether these water levels come down or continue to increase.

Spring Flood Outlook

On Thursday, the National Weather Service released their second Spring flood outlook which stated that the risk of spring flooding is currently above average with minor to moderate flooding expected along the Illinois River. Thanks to warmer temperatures this winter, snowpack, frost depth, deep layer soil moisture and streamflow conditions are not expected significantly contribute to spring flooding. Instead, any flooding along the Illinois River will largely be driven by spring rains. You can read the NWS’ Spring Flood Outlook here.

Spring Climate Outlook

The Climate Prediction Center’s latest outlook for Spring (March, April, May) calls for an equal chance of above average, near average, or below average temperatures over Central Illinois. It also calls for a greater chance of above average precipitation which would give the area more opportunities for severe storms.