Tuesday Weather Update

Illinois Road Conditions
Southern Wisconsin Road Conditions

9:41pm Update: Big developments in the forecast... but all for the good. As the heaviest of our snow pushes west into Iowa and winds slowly start to calm down, we have been dropped from our Winter Weather Advisory. Despite the change, roads will still be treacherous in spots tonight, so be careful! A few advisories and warnings will remain in effect, especially McHenry (IL) and Walworth (WI) counties because of lake-effect snow. As snow winds down, here's a look at preliminary snow totals:

Remember to send your snow totals to weather@wtvo.com!

Illinois Road Conditions - 8:12pm

8:24pm Update: Main roads are still looking messy around Illinois. If you're out, stay safe out there! Red indicates snow covered roads. Yellow means patchy slick spots and green means roads are generally clear.

7:33pm Update: Snow becoming more scattered in nature. Heavier snow showers in Carroll and northern Whiteside counties... as well as a line ranging from Winnebago to northern Boone.

(7:30:41 PM) nwsbot: Local Storm Report by NWS LOT: Cherry Valley [Winnebago Co, IL] broadcast media reports SNOW of M3.5 INCH at 07:27 PM CST --

(7:24:11 PM) nwsbot: Local Storm Report by NWS LOT: Harvard [Mchenry Co, IL] broadcast media reports SNOW of M6.0 INCH at 07:22 PM CST --

(7:14:52 PM) nwsbot: Local Storm Report by NWS LOT: Winnebago [Winnebago Co, IL] broadcast media reports SNOW of M3.1 INCH at 07:00 PM CST -- liquid equivalent 0.30 inches.

6:24pm Update: Radar showing another pocket of heavy snow in northern DeKalb County. Drier air in Rockford for the moment.

(6:26:18 PM) nwsbot: Local Storm Report by NWS LOT: Woodstock [Mchenry Co, IL] co-op observer reports SNOW of M5.0 INCH at 06:13 PM CST -- storm total 5.0 inches. snow depth 6 inches. liquid content 0.57 inches.

(6:17:47 PM) nwsbot: Local Storm Report by NWS MKX: Newark [Rock Co, WI] trained spotter reports SNOW of M1.5 INCH at 06:09 PM CST -- blowing and drifting snow. snow covered roads.

5:42pm Update: We have seen a few updates to our watches and warning. McHenry (IL) and Walworth (WI) are now under a Winter Storm Warning because of expected snow totals. This doesn't really change the big picture... we're still talking snow and heavy winds through the rest of this evening.

5:28pm Update: Radar is continuing to show pockets of dry air moving through the Stateline, although we are still seeing moderate snow showers in areas around Oregon, Dixon, Rochelle, and DeKalb.

(5:14:34 PM) nwsbot: Local Storm Report by NWS LOT: 1 ESE Winnebago [Winnebago Co, IL] cocorahs reports SNOW of M1.1 INCH at 05:00 PM CST -- storm total 1.1 inches.

(5:10:36 PM) nwsbot: Local Storm Report by NWS LOT: Cary [Mchenry Co, IL] public reports SNOW of E5.5 INCH at 04:45 PM CST -- total so far.

(5:05:48 PM) nwsbot: Local Storm Report by NWS LOT: Byron [Ogle Co, IL] public reports SNOW of E2.4 INCH at 05:04 PM CST --

(4:42:03 PM) nwsbot: Local Storm Report by NWS LOT: 2 N Winnebago [Winnebago Co, IL] broadcast media reports SNOW of M2.1 INCH at 04:38 PM CST -- storm total 2.1 inches at wrex.

(4:32:24 PM) nwsbot: Local Storm Report by NWS LOT: 2 WNW Bull Valley [Mchenry Co, IL] trained spotter reports SNOW of M6.1 INCH at 04:20 PM CST -- storm total 6.1 inches so far.

(4:22:30 PM) nwsbot: Local Storm Report by NWS LOT: Crystal Lake [Mchenry Co, IL] trained spotter reports SNOW of M5.0 INCH at 04:06 PM CST -- storm total 5.0 inches. several vehicles in ditches.

(5:05:09 PM) nwsbot: Local Storm Report by NWS DVN: Erie [Whiteside Co, IL] public reports SNOW of E4.2 INCH at 04:59 PM CST --

4:15pm Update: Our patch of dry air is now moving into northwestern Illinois with more snow moving back in behind it.

(4:16:32 PM) nwsbot: Local Storm Report by NWS LOT: Rockford [Winnebago Co, IL] trained spotter reports SNOW of M3.0 INCH at 04:11 PM CST -- storm total 3.0 inches so far. 

3:45pm Update:

(3:44:23 PM) nwsbot: Local Storm Report by NWS LOT: Mchenry [Mchenry Co, IL] public reports SNOW of M5.0 INCH at 03:43 PM CST --

(3:41:12 PM) nwsbot: Local Storm Report by NWS LOT: DE Kalb [De Kalb Co, IL] trained spotter reports SNOW of M3.3 INCH at 03:30 PM CST -- updated report. storm total so far after 4 hours. 1.5 inches in past 1.5 hours. moderate snow with low visibility at time of report.

(3:39:14 PM) nwsbot: Local Storm Report by NWS LOT: DE Kalb [De Kalb Co, IL] trained spotter reports HEAVY SNOW of M2.5 INCH at 03:00 PM CST -- storm total so far at northern illinois university.

(3:35:07 PM) nwsbot: Local Storm Report by NWS LOT: 3 WNW Bull Valley [Mchenry Co, IL] cocorahs reports HEAVY SNOW of M5.5 INCH at 03:30 PM CST -- updated report storm total so far. 1.5 inches in past hour. still heavy snow but smaller flake size.

(3:33:06 PM) nwsbot: Local Storm Report by NWS LOT: 3 WNW Bull Valley [Mchenry Co, IL] cocorahs reports HEAVY SNOW of M4.5 INCH at 02:30 PM CST -- 2.1 inches in past hour up to time of report. follow up call with bull valley pd indicated numerous motorists stranded on side of roadways and numerous accidents. agencies have gone to their emergency snow plan. plows cannot keep up with snow due to significant blowing and drifting

(3:44:03 PM) nwsbot: Local Storm Report by NWS MKX: 1 E Lake Geneva [Walworth Co, WI] public reports SNOW of E2.0 INCH at 03:07 PM CST -- storm total so far

(3:45:03 PM) nwsbot: Local Storm Report by NWS DVN: Rock Falls [Whiteside Co, IL] trained spotter reports SNOW of M3.3 INCH at 03:21 PM CST -- heavy snow

3:20pm Udpate: Good news for our friends along the I-88 corridor. We're starting to see a break in the snow! It is most pronounced in Lee County, but don't be fooled. More snow is coming and strong winds are expected to continue through the evening, meaning continued whiteout conditions, blowing and drifting snow, and messy roads. Stay safe out there!

3:00pm Update:

(2:59:53 PM) nwsbot: Local Storm Report by NWS LOT: 3 WNW Bull Valley [Mchenry Co, IL] cocorahs reports HEAVY SNOW of M5.5 INCH at 02:30 PM CST -- 2.1 inches in past hour up to time of report. follow up call with bull valley pd indicated numerous motorists stranded on side of roadways and numerous accidents. agencies have gone to their emergency snow plan. plows cannot keep up with snow due to significant blowing and drifting.

(2:59:25 PM) nwsbot: Local Storm Report by NWS LOT: Rockford [Winnebago Co, IL] public reports SNOW of M1.9 INCH at 02:51 PM CST -- in central rockford. broadway and 7th street.

(2:57:29 PM) nwsbot: Local Storm Report by NWS LOT: Stillman Valley [Ogle Co, IL] public reports SNOW of M1.9 INCH at 02:56 PM CST -

(2:49:40 PM) nwsbot: Local Storm Report by NWS LOT: N Capron [Boone Co, IL] cocorahs reports HEAVY SNOW of M1.5 INCH at 02:00 PM CST -- snow so far. snow began at 100pm. visibility occasionally less than 1 block during frequent wind gusts.

(2:58:21 PM) nwsbot: Local Storm Report by NWS DVN: Deer Grove [Whiteside Co, IL] trained spotter reports SNOW of M5.0 INCH at 02:53 PM CST -- light snow continues

(2:58:22 PM) nwsbot: Local Storm Report by NWS DVN: 1 WNW Morrison [Whiteside Co, IL] trained spotter reports SNOW of M1.5 INCH at 02:55 PM CST -- current conditions - heavy snow and very windy

2:45 Update: Roads are continuing to go downhill fast thanks for bursts of heavy snow and strong winds. Here's a picture Candice took of Highway 20 heading east. Remember to slow down and use extra caution because near whiteout conditions are being reported across the area.

Here are visibilities as of 2:45pm. The most affected areas start around Freeport and Rockford and head south and east. Expect these conditions to continue over the next several hours.

Storm reports from the NWS:

(2:46:13 PM) nwsbot: Local Storm Report by NWS LOT: NE Rockford [Winnebago Co, IL] public reports SNOW of E1.0 INCH at 02:30 PM CST -- visibility half mile.

(2:39:34 PM) nwsbot: Local Storm Report by NWS LOT: Capron [Boone Co, IL] trained spotter reports HEAVY SNOW of M1.5 INCH at 02:02 PM CST -- snowfall in 1 hour. blowing snow and snow covered roads.

(2:37:21 PM) nwsbot: Local Storm Report by NWS LOT: DE Kalb [De Kalb Co, IL] trained spotter reports SNOW of M1.8 INCH at 01:55 PM CST -- snow total so far in past 2 hours. a few hundred feet of visibility in wind driven snow. occasional whiteout conditions. snow is drifting.

(2:26:58 PM) nwsbot: Local Storm Report by NWS LOT: Poplar Grove [Boone Co, IL] trained spotter reports HEAVY SNOW of M1.5 INCH at 02:20 PM CST -- storm total as of 200pm. ground blizzard in open areas. east west oriented roads...particularly rt 173 are drifting over and practically impassable. also very icy road surface leading to numerous accidents. visibility at time of report 1/4 to 1/2 mile.

(2:25:43 PM) nwsbot: Local Storm Report by NWS LOT: Spring Grove [Mchenry Co, IL] public reports SNOW of E4.0 INCH at 02:22 PM CST -- snowing since 1 pm.

(1:55:27 PM) nwsbot: Local Storm Report by NWS LOT: WNW Bull Valley [Mchenry Co, IL] cocorahs reports HEAVY SNOW of M1.9 INCH at 01:30 PM CST -- storm total so far. snow began at 1220 pm. heavy snow at time of report.

2:23pm Update: Our precision doppler is still showing the heaviest snow south & east of Rockford. Visibilities under a mile in these spots. Expect near whiteout conditions to continue through this evening, especially in open areas and rural roads.

Jamie Vertz and Mike Sharp - Rochelle

Here's a viewer picture from Jamie Vertz and Mike Sharp in Rochelle showing the snow just after 2pm.









(1:33:28 PM) nwsbot: Local Storm Report by NWS DVN: Sterling [Whiteside Co, IL] trained spotter reports SNOW of E2.0 INCH at 01:17 PM CST -- heavy snow is falling...via espotter

1:30 pm Update:  Moderate to heavy snow will contine from southeast Wisconsin through north-central Illinois to the Quad Cities.  Snowfall rates of half an inch to an inch per hour will be possible with the more heavier snow.  Whiteout conditions have been reported south of Rockford near Oregon, DeKalb, Sycamore, Dixon and Rochelle.  Travel will become dangerous this afternoon and evening.





(11:57:32 AM) nwsbot: Local Storm Report by NWS LOT: DE Kalb [De Kalb Co, IL] trained spotter reports HEAVY SNOW of M0.5 INCH at 11:56 AM CST -- niu. last 30 min.

12:40 pm Update:  Heavy snow is falling near Chicago and surrounding suburbs early this afternoon.  Moderate to heavy snow has also been falling south of Rockford.  Visibility within the heavier snow has dropped to less an a mile, and in some cases less than a half mile further east.

11:30 am Update: Winter Storm Warning just issued for Carroll and Whiteside counties beginning now and lasting through Noon Wednesday.  A Winter Weather Advisory continues (tan shading) for the remaining N. IL and S. WI counties.

10:45am Update: The leading edge of the rain, snow and sleet is beginning to overtake the dry air in place from earlier this morning.  Already sleet has been reported in Naperville and downtown Chicago and this will continue to lift north and west.  The area highlighted on the satellite and radar image is what's known as the 'deformation band'.  It's usually where the strongest precipitation, whether it be rain or snow, occurs and is found just north and northwest of low pressure.  Watching this throughout the morning it's slowly been lifting north and will continue to move into Northern Illinois and Southeast Wisconsin through the afternoon. Going forecast for snow totals around 3" still looks on track with snow to liquid ratios remaining right at or slightly below 10:1 (meaning heavy, wet snow).  Road conditions will rapidly deteriorate once the snow begins.  Winds continue to gust around 35 mph which will cause blowing snow through the afternoon and early evening.

A dry east wind is in place across Northern Illinois and Southern Wisconsin this morning.  A mixture of sleet, snow, rain and even freezing rain has been falling downstate while a switch to heavy, wet snow has been falling in southeast Iowa, Northern Missouri and West-Central Illinois.  The dry east wind will keep the leading edge of the precip to the south through the morning but by early afternoon the atmosphere quickly saturates allowing a wintry mix to move in from south to north roughly along I-88.  As the low moves into East-Central Illinois later this afternoon temperatures will be in the low 30s but cooling temperatures a couple thousand feet above will allow a transition to a heavy, wet snow from mid-afternoon to this evening.  Accumulations will range from just a couple inches north to close to 4" south.  It's possible there may be a few isolated locations that reach close to 6", but I think most will receive closer to 3".  Despite snow totals the strong east/northeast wind will cause road conditions to deteriorate once the snow does fall late this afternoon and visibility will drop as well.

A Winter Weather Advisory will go into effect at Noon today for all of Northern Illinois and Southern Wisconsin.