First the snow, then the cold

It's nice to finally be able to see some sun this afternoon!  Unfortunately the view from inside is a lot better than what it is outside!

Temperatures this afternoon will remain in the low 20s but with northwest winds gusting as high as 35 mph at times wind chills have dropped into the upper single digits and are expected to remain that way through the majority of the afternoon.  In fact, wind chills around 1pm will range from 5° to 13°!  Brrrr....

Don't look for much improvement tonight, either.  High pressure moving in will ease some of the wind but it is going to get cold.  Overnight lows will drop between 5° and 9° with wind chills dropping near or slightly below zero just before dawn Saturday.  Temperatures this weekend will remain in the 20s with a few 30s likely in areas that didn't receive much snow on Thursday.  Another cold blast of air is expected by the middle of next week with several waves of energy expected to move through.

Thursday Storm Reports (So Far...)

Here's a look at some of the snow totals and wind gusts seen throughout the Stateline as of 11:00pm Thursday night. We'll update these numbers as we get them.

Green County (WI)

6:30pm

Monroe – 6.8” of snow

Monroe Airport – 45mph gust

Jo Daviess

8pm

Stockton – 50mph gust / 7.5” of snow (As of 3:45pm)

5:45pm

Galena – 8” of snow

Stephenson

4pm

Winslow – 9” of snow / 0.25 mile visibility / Blizzard Conditions

9pm

Lena – 12”
3:30pm
Lena - 30-40mph winds / Blizzard Conditions
8:15pm
Freeport - 6.5"

Carroll

7pm
Thomson - 4" of snow
4pm

Lanark – 4” of snow

Whiteside
8pm
Morrison - 3.5" of snow

Ogle
10pm
Polo - 3.9" of snow
7pm
Mount Morris - 3.3" of snow

Winnebago

8:30pm
Winnebago – 3.9” of snow
8pm
Roscoe - 3.5" of snow 

6pm

Rockford Airport – 0.5” of snow

3:30pm

Rockford – 2” of snow

Boone

3:30pm

Capron – 1” of snow

McHenry

10pm
Cary - 0.9" of snow
6:30pm

Huntley – 1” of snow

Thursday morning update

11:20am Update:  Blizzard conditions are expected to move east of the Mississippi River between Noon and 2pm this afternoon and continue east towards Chicago after 4pm.  Temperatures are already beginning to cool and as winds shift around to the northwest they will pull even cool air over the Stateline.  A mix of rain/sleet/snow may occur before a complete change to snow.  Visibility in Iowa where the wind has picked up and the snow has fallen have been reduced to les than a quarter mile and snowfall rates near 1" per hour.  Again, travel will become difficult through the afternoon and evening with the strong winds and possibly icy roadways.


Earlier Update:

Blizzard Warnings have been extended further east this morning to include Stephenson, Carroll, Whiteside, Winnebago, Boone, Ogle and Lee counties.  These will go into effect at Noon and last through midnight tonight.

Don't be fooled by the rain falling this morning because the snow will come by this afternoon.  Rain will continue through the morning with temperatures beginning in the upper 30s to low 40s.  As cold air wraps in from west to east the transition to snow will begin to take place during the afternoon and last through the evening.  The snowfall forecast hasn't changed much from the previous forecast but I have noticed a dry-slot wrapping around the low that currently sits near St. Louis, MO.  Once the low moves into Illinois around noon today there may be a lull in the precipitation before the snow begins to fall.  As we've been talking about all week the biggest concern with this storm will be the wind.  Sustained winds around 30-40 mph will gust as high as 50 mph through the evening.  Even if a few inches of snow only fall the strength of the wind could cause near blizzard like conditions and that's why Blizzard Warnings have been issued.

One concern I do have with the rain falling this morning is that when temperatures begin to drop and the snow begins to fall it could create some slicks spots on roadways.  Again, look for rain to continue through noon today with a changeover to snow from west to east into the afternoon.  Winds will pick up from the north and northwest with gusts as high as 50 mph which will cause lowered visibility as the snow falls.  Roads may be icy late tonight and early tomorrow until the snow ends around midnight tonight.

Winter Storm Update

Our first winter storm of the season is on our doorstep, but it won't exactly feel winter-like at first. Here's a complete timetable of what the Rockford Metro area will experience over the next 24-36 hours.

Rain moves in this evening with a few snowflakes mixing in as temps dip into the mid 30s. Temps actually warm into the upper 30s overnight, meaning all rain after midnight... maybe even a rumble of thunder. Areas to our far north and west (Iowa to central Wisconsin) will more than likely see all snow during the overnight.

All this rain will eventually turn to heavy, wet snow on Thursday... starting to our west and moving east as the day progresses. For Rockford, this switchover will take place around midday. Afternoon winds pick up quite a bit with wind gusts around 50mph, which will blow around whatever snow is on the ground. This will cause limited visibilities and brief blizzard conditions through the day. A rumble of thunder is still possible through the afternoon. Heavy snow and strong winds are expected to continue through the evening.

There are a number of warnings out. With the exception of some Blizzard Warnings already in effect to our west, most of these warnings do not kick in until Thursday morning. The majority of northern Illinois is under a Winter Storm Warning, with Jo Daviess and southern Wisconsin under a Blizzard Warning.

Snow totals will vary, but the heaviest snow will be to our north and west. Areas under the Winter Storm Warning will generally see 4-7" of total accumulation by Friday morning. If we get any thunder, those areas will see higher totals. Areas under the Blizzard Warning will generally see 8-12" of accumulation. Isolated areas closer to central Iowa and central Wisconsin could see more.

Stay with the First Warn Weather team for the latest on this developing storm!

Significant snow and blizzard conditions likely across Wisconsin, Illinois and Iowa

11:45 am Update:  There have been no significant changes to the forecast from earlier this morning.  Winter Storm Watches have been extended further east to cover the Chicago Metro area.  Precipitation in southern Wisconsin and northwest Illinois will likely already be starting off as snow Thursday morning with rain or a rain/snow mix further east and southeast.  Low pressure is expected to move very close to Chicago by Noon Thursay with cold air wrapping south of the low in central Illinois.  Heavy snow will continue from Monroe to west of Freeport with a transition to snow between Noon and 3pm elsewhere.  Once the snow begins the speed at which the air is rising in the atmosphere behind the low will increase likely causing a period of heavy snow to fall at rates of 1" to 2" per hour for a time.  This combined with wind gusts nearing 45mph or 50mph will make afternoon and evening travel very difficult. 

Earlier Post:

Winter Storm Warnings continue for southern Wisconsin and northern Illinois beginning this evening and lasting through Thursday evening. 

Blizzard Warnings have been issued for Green and Rock counties in Wisconsin and will go into effect Thursday afternoon.  A Blizzard Warning has been issued for Jo Daviess County and will go into effect later tonight and last through Thursday evening.

Our first winter storm will make its presence known late tonight and definitely by Thursday morning as warm, moist air drawn in from the Gulf will mix with cold Canadian air from the north.  Low pressure will track from Oklahoma tonight to St. Louis, MO by Thursday morning and near South Bend, IN by Thursday night.  Initially precipitation across north-central and northeast Illinois will begin as a light rain/snow mix after 4pm/5pm this evening and continue overnight. West and northwest of Rockford may experience a little more snow at the onset as temperatures will remain closer to or slightly below freezing from central Wisconsin to northeast Iowa.  As the low moves northeast overnight and early Thursday morning I wouldn't be surprised if there were a few rumbles of thunder; both where the rain is falling and where the snow if falling.  By mid-morning Thursday low pressure will strengthen very close to the Stateline which will cause the wind to increase and possible thundersnow to develop in southern Wisconsin and northwest Illinois.  Where thundersnow is observed it's possible totals may exceed 10", but this is expected to remain north and west of the immediate area.  There will be light rain mixed with snow early Thursday morning but as the low moves south of Chicago by the afternoon the cold air will move in from west to east and change any leftover rain to snow by Thursday afternoon.  Snowfall totals will be less the further east and southeast of Rockford and higher the further north and northwest of Rockford.  In fact, locations from Madison to Monroe to just west of Freeport to Mt. Carroll and Galena could see totals nearing 12" while locations closer to Rochelle, DeKalb and Sycamore could have totals near 4".

It's important to not necessarily focus on the snow totals but the wind that will accompany this storm.  The low will strengthen significantly once it moves into Illinois by late morning Thursday causing northwest winds to gust as high as 50 mph.  Near blizzard-like conditions will be found from southern Wisconsin to northwest Illinois and expand east through the day and road conditions are expected to deteriorate through Thursday evening.  With temperatures nearing 32° as the switch from rain to snow occurs we'll experience a heavier snow which may cut back on drifting some but where higher totals occur it could weigh down trees and power lines.

Our First Winter Storm: What To Expect

Let me start off by saying this forecast can still change a little, but no matter what happens, the weather is going to create plenty of problems Wednesday night and Thursday, possibly even into Friday.

Model runs are coming into agreement that Thursday's winter storm will stay just to our south. I've outlined what to expect the next couple days with our Winter Storm Impact Forecast.

Things kick off Wednesday with evening showers. A few snowflakes will mix in as we go through the night. There's even enough energy in the atmosphere that we could get a rumble of thunder early on.

Courtesy: National Weather Service

That rain/snow mix eventually switches over to all snow on Thursday. When it switches will determine how much snow we get. The National Weather Service is expecting our precip to be all snow by late morning, although the timing could be off by a few hours.

Now the big question... how much snow? Initial forecasts are showing heavier amounts staying to our northwest, but we are really close to getting some big snow totals. Right now, I'm going 4-6" in the Rockford Metro, with heavier amounts to the northwest.

Effective Wednesday Night and Thursday

The biggest concern with this system will be Thursday night into Friday, as winds gusts are expected to pick up somewhere in the 40-50mph range. Because this is going to throw a lot of snow around, the National Weather Service has issued WINTER STORM WATCHES for most of the Stateline and WINTER STORM WARNINGS for Jo Daviess County and all of southern Wisconsin.

If this storm moves, even a little bit, it could impact snow totals, but the strong winds are coming regardless, so be careful if you're doing any traveling the next couple days!

More updates as we get them! -BA

Winter Weather Update

A Winter Weather Advisory has been issued for Green, Rock and Walworth counties through this evening for the light snow that is currently falling in southern Wisconsin.

A Winter Storm Watch has been issued for all northern Illinois and southern Wisconsin counties beginning late Wednesday evening and lasting through Thursday afternoon.

As the morning model runs continue to come in we're beginning to gain a better idea of where exactly low pressure will move Wednesday night into Thursday afternoon.  While there are subtle differences between runs and the models themselves they are starting to converge on a general track taking the low from north-central Oklahoma to northern Missouri by midnight Wednesday to northern Illinois by Thursday morning and into Indiana by Thursday afternoon.  With this current track it still appears as if the heaviest of the snow will occur just to the north and west of Rockford with places like Mt. Carroll, Stockton, Elizabeth, Freeport, Monroe and Madison receiving some of the higher totals.  Locations east and southeast of Rockford look to receive slightly less due to warmer air at the onset of the storm.

Here's what we know so far and what you need to know now:

Light snow will continue to fall north of the state line through this afternoon with quiet weather expected through tonight and the first half of Wednesday.  Temperatures are expected to rise above freezing during the afternoon Wednesday so any precipitation that does fall should fall as rain before mixing with light snow by Wednesday night in north-central Illinois. All snow or a quicker transition to snow will likely occur from southern Wisconsin, far northwest Illinois and Iowa where the cold air will be in place the longest.  As the low moves into Illinois it is still expected to strengthen which would increase the north wind from Wisconsin through Illinois by Thursday afternoon.  We do know a transition to snow will occur mid-morning Thursday with snow continuing through the afternoon.  The quicker the transition the higher the snow fall totals and the slower the transition the lower the snow fall totals.  One important thing to note is that even if we receive a few inches of snow fall the strong winds will cause blizzard like conditions through Thursday evening.   Travel will be impacted from mid-morning Thursday to Thursday night with some improvement in conditions by Friday morning.  As we get closer to the event we'll continue with updates and be able to better pinpoint who will receive what and how much snow will actually fall.  It's important to us to make sure we have the most up-to-date information to provide you with a better forecast!  Evening Meteorologist Brandon Arnold will have another update and storm break down for you on the news at 5pm, 6pm, 9pm and 10pm.