(11:30PM - 9/27/19) A brief short term update regarding the ongoing heavy rain and flood threat across portions of Northern and Central Illinois... Major flooding is ongoing across portions of the aforementioned areas at this time. Since this morning, upwards of 4-9" of rain has fallen in an axis from Western Illinois/Iowa border area on east to the Illinois/Northwest Indiana border area. Widespread and significant areal, road and home flooding has been occurring across these areas...with travel disruption, road closures and water rescues having occurred. Travel is discouraged across these areas and precautions should be taken for ongoing and/or impending flooding issues.
Additional rain and t'storms will be possible across this axis for the next several hours, which could potential drop another 0.50-2.50" of rain on top of what has already fallen. This will bring rainfall totals across this axis to 5-11" by tomorrow morning.
The wet pattern that has been in place will continue, with another storm system expected to bring heavy rainfall and flooding concerns to portions of the state, through Sunday morning.
A storm system pushing through the region will bring multiple rounds of rain and t'storms to portions of the state, through Sunday morning. An initial round of rain and t'storms pushed across much of Northern and portions of Central Illinois this morning through this afternoon. Widespread rainfall totals of 0.50-2.00" occurred with this activity across the aforementioned areas, with an isolated corridor of 3-7" having occurred along a Peoria to Pontiac axis.
A second round of rain and t'storms has been pushing across much of Northern and Central Illinois this evening and into tonight, continuing overnight and into Saturday morning for some areas. Widespread rainfall totals of 0.50-5.00" have occurred with this round of activity. Additional widespread rainfall totals of 0.50"-3.00" are likely with this activity. A third and final round of rain and t'storms will be possible Saturday night through Sunday afternoon, once again across much Northern and portions of Central Illinois. Rainfall totals with this round should range from 0.25-2.00".
The repeated rounds of rain and t'storms over the same areas, along with expected training, will allow for widespread rainfall totals of upwards of 1-3" across much of Northern and portions of Central Illinois during the aforementioned time-frame. Within this main axis, a corridor of 5-10" rainfall totals are expected, with isolated higher amounts possible. Given the wet pattern that has been in place the past several weeks, along with the expected heavy rainfall, low to moderate flood potential will exist across portions of Northern and Central Illinois.
Below is the TAM flood forecast through Sunday morning.