(10:00PM - 10/28/19) A rare and historic/record breaking snowstorm continues to affect the region, and will continue to affect the state through Thursday evening. One period of accumulating snow occurred last night into this morning across portions of Western and Northern Illinois. The second period of snow will affect much of Northern and Central Illinois, tonight through Thursday evening.
The first period of snow occurred in a narrow corridor last night into this morning, across portions of Western and Northern Illinois. Upwards of 1-4" of snow occurred in this narrow axis, which ran extended from near a line in the vicinity of Galesburg to La Salle to Naperville.
The second period of snow will occur across Northern and Central Illinois tonight through Thursday evening. A large area of precip has blossomed across the region this evening, as the storm system further organizes. As this is occurring, colder air is beginning to wrap into the system, which is allowing rain to gradually turn to snow from west to east across Northern and Central Illinois. As of this posting time, rain has turned to snow across much of Northwest, North-Central and Western Illinois. Rain will transition to snow across the remainder of Northern and Central Illinois overnight and into Thursday morning. Snow will then continue across these areas into Thursday afternoon, gradually ending from west to east. Several inches of accumulation will be likely tonight into Thursday afternoon for the aforementioned areas, with upwards of 3-6" being possible for a large portion of Northern and portions of Central Illinois, with locally higher amounts possible.
Below is our TAM snowfall forecast for this event. This forecast map is the combined final expected snowfall totals for the entire event, including both periods of accumulating snow (Tue night-Wed morning & Wed night-Thur eve).
As mentioned in previous posts... While this snowstorm will not be noteworthy a few months from now in the heart of winter, it is quite significant for this time of year and by October standards. This snowstorm has the potential the be one of the biggest, if not the biggest snowfall on record for October in some affected areas. Thursday will also likely end up being the snowiest Halloween on record for many affected areas, with some places likely crushing the current standing records by several inches. To top it off, some places will likely approach, if not surpass the all-time record snowiest October on record. October snowfall statistics for a few selects cities are below. Many of these listed current records will be in jeopardy.
Snowiest October Days: 3.8" - 10/19/1989 & 3.0" - 10/20/1952
Snowiest Halloween: 0.1" - 2014
Snowiest Octobers: 6.3" - 1989 & 4.4" - 1967 .....(Already at 1.2" this month to date)
Snowiest October Days: 5.0" - 10/23/1929 & 2.0" - 10/27/1925 + 10/29/1917
Snowiest Halloween: 0.1" - 2014
Snowiest Octobers: 5.0" - 1929 & 3.0" - 1917 .....(Already at 0.5" this month to date)
Snowiest October Days: 6.5" - 10/26/1967 & 2.9" - 10/25/1898
Snowiest Halloween: T - 1954/1939/1926/1918/1917/1908
Snowiest Octobers: 6.6" - 1967 & 2.9" - 1898 .....(Already at 1.1" this month to date)
Snowiest October Days: 3.3" - 10/23/1929 & 1.9" - 10/29/1925
Snowiest Halloween: T - 1918
Snowiest Octobers: 3.3" - 1929 & 1.9" - 1925 .....(Already at 0.1" this month to date)