January's Outlook

Happy New Year! Now that the calendar has flipped over to January, 2016 we turn our eyes towards the expected weather pattern for the month. The Climate Prediction Center has issued an updated temperature and precipitation outlook for the month of January. Overall, for the Stateline, it looks like the month will average out to roughly normal regarding precipitation and temperatures.

Temperatures are expected to near average, if not slightly above, by the time the month of January comes to an end. However, the core of the above average temperatures will shift northward into Southern Canada. This is different than what we saw in December, which featured a higher likelihood of seeing above average temperatures across the Stateline. So, if you were not a fan of the milder temperatures, January's outlook is slightly better. Some cold outbreaks will likely make their way into the Midwest and Great Lakes, which is something that was essentially absent throughout the month of January.

In terms of precipitation, the month of January is forecast to contain slightly drier than average conditions. However, with the Stateline's location on this map, it will likely factor out to be nearly average regarding precipitation for the month. In a typical January, we see roughly 10" of snowfall. Therefore, if this outlook comes to fruition, the area can expect roughly 10" of snow by the end of the month. December saw a lack of snowfall with 4.5" falling. Our average snowfall for December is roughly 11". So, snow lovers can rejoice...a little. More snow is expected in January overall than what we saw in December.

Dry Stretch of Weather Helpful in Flooded Areas

The days leading up to and following Christmas were anything but joyful for many.  From severe weather in Texas, to winter weather on the other side of the state.  Ice storms and flooding rains from the south to as far north as central Illinois, it will be nice to have a week of just dry weather.

Here's the 5 day precipitation outlook for the United States and as we head into 2016.  The southern branch of the jet stream will turn a little more active keeping a lot of the wet weather from the west to the southeast.  There is the potential for some flooding with this pattern, but at least for residents along the Mississippi and Missouri rivers, as well as other local rivers who are dealing with historic flooding, skies will remain dry.

Unfortunately, river levels will continue to run high and in major flood stage for the next several days, but after the weekend (assuming little precipitation falls) those levels will begin to recede.  Each green line you see on the map to the left is a flood warning for some portion of a river.  You can almost follow the Mississippi River and where other rivers spill into it.  Let's hope the drier pattern sticks around a little further into January.

Warm December & New Year's Outlook

The pattern this winter thus far has not lacked attention. A blocking high pressure system in the Atlantic Ocean and a low pressure system "stuck" near Newfoundland has disallowed extreme cold and winter weather to move into the region. In fact, December 30th is the first day of the entire month where high temperatures remained below the 30-degree mark. This is something that does not typically happen in the Midwest during the month of December. Just how warm has it been?

 The average high temperature in the month of December in Rockford is 33°. Thus far, we have seen an average high temperature of over 44°. That makes for a +11° temperature difference. The average low temperature during December is 17°. We have only seen one night with temperatures at or below this temperature. In fact, our average low temperature this month matches our typical high temperature for the month of December. For the state of Illinois overall, the most above average December in terms of temperatures is likely, beating the old record set back in 1923.

The good news for cold and snow lovers is a change in the overall pattern is upcoming for the eastern half of the country. The blocking high will be further north. This will allow colder air to filter into the Midwest, Plains, Great Lakes, Ohio Valley, Tennessee Valley, and Northeast more often. Does this mean we will see more snowfall? Not necessarily. While the temperatures will be colder in January and February, we may stay slightly drier than average. Nonetheless, more snow is likely, but it is difficult to say how much and if we will see a significant snowstorm.

The cold air is settling in this evening, and it will be around for New Year's Eve. Temperatures will likely start near 20° before warming into the middle 20's in the afternoon.

By the time we get into the evening when many of the activities start, clouds will begin eroding and temperatures will start falling through the teens. By the time we ring in 2016, temperatures will be in the lower to middle teens. So while we had a mild November and December, the beginning of January looks colder. There could be a few days where our high temperatures are actually below average!

Tracking the Morning Snow

A quick moving system will bring a blast of accumulating snow to the Stateline....at least for some. A potent disturbance in the upper levels of the atmosphere will head northeast from Missouri through north central Illinois.

Snow that generated in the eastern plains last night starting tracking to the northeast overnight and is now in Iowa and Missouri. The snow is expanding into west central Illinois and into southern portions of the Stateline.

Oregon and Dixon currently getting the snow as it spreads northeast. Overall, the Stateline will see a dusting to an inch of snow. The most favored area of accumulating snow will be south and west of Rockford. Local amounts of an inch are possible, but generally expect a dusting to a half inch.

A moderate band of snow is currently tracking through Peoria and will move into the Chicago suburbs, and this area has a better outlook to see an inch of accumulation. If you are heading out along I-90, south on 39, or east on Hwy 34 or 88, watching for quickly reduced visibility and slick roads if they are untreated.

Good news is, the snow moves out by noon, and you probably won't need to break out the snowblower again today. It stays dry, but cold, into the new year.

Blast of Winter Air Heading for Stateline

December will go down as above average month in terms of temperatures with nearly every day of the month featuring temperatures at or above average. We had one major winter storm, which occurred on the 28th. It dropped significant sleet, ice and snow accumulations across the Stateline and caused numerous problems on the roads.

Now our attention turns towards what's next. For Northern Illinois and Southern Wisconsin, a potent, but relatively dry disturbance in the upper atmosphere will move through the region Wednesday morning into the early afternoon hours from southwest to northeast. It will be accompanied by cold air, so the precipitation it does bring into the region will fall as snow. Snow looks likely, but accumulations look light at this time. By the time the snow showers end--and they should be light to possibly moderate at times--we will see a covering to upwards of an inch or so of accumulation.

As quick as those snow showers move in, they will move out so that by Wednesday afternoon we will be dry, but cloudy. Then, our attention shifts to the very cold air that will push into the region from Canada.

Back on December 23rd, we saw record high temperatures across the area, including a high of 59° in Rockford. Since then, we have seen a steady and steep decline in temperatures. That pattern will continue as we head into the New Year. A downward trend in temperatures is expected to round out 2015 and ring in 2016 as several days in the 20's and teens are forecast, including a high of 18° on New Year's Day. This bitterly cold air will be accompanied by dry conditions, which is good news.

It will be some of the coldest air we have seen thus far this season, especially when you take into account how mild it has been. The reasoning behind why it's going to get cold and potentially stay colder for awhile is because of what we refer as the North Atlantic Oscillation and the Arctic Oscillation. These two teleconnection variables have been positive this winter thus far. However, models are suggesting a more negative trend in both of these as we round out December and enter 2016. When these are negative, that usually means colder air from the Mississippi River to the East Coast.

Here is a visual of what the negative NAO pattern looks like during the winter. Notice the "dip" in the jet stream across the Midwest, Great Lakes, Ohio Valley, Northeast, Mid-Atlantic, and New England. That means colder temperatures and a more active pattern in terms of storm systems. While the majority of storm systems affect the Northeast, Mid-Atlantic and New England, the pattern for the Stateline also becomes slightly more active. Therefore, it looks like colder temperatures are here for awhile, and we could see a few shots of snow as well over the next several weeks.

More Snow for the Stateline

While all of the Winter Storm Warnings for the Stateline have expired, we still have to get through a little more snow before a period of dry weather arrives.

For Tuesday morning we're noticing light flurries and even patchy freezing drizzle mixing in across portions of the Stateline. This could cause more slickness on the already slick
roads as you head out, so it'll be one of those mornings you'll want to take your time. The rest of the afternoon will be cloudy and colder as temperatures fall into the upper 20's.


Another disturbance will pass through the Stateline area Wednesday morning. This will produce enough lift in the atmosphere to get snow to fall. We won't see much in term of accumulations, around an inch or so through noon Wednesday. It will be just enough to keep roads slick again through Wednesday, so another day to take it slower. The rest of the day will be cloudy and colder with high temperatures near 30°.

After Wednesday, we'll see a period of direr weather for the Stateline. That doesn't mean we won't see any rain or snow, but overall the active pattern that we had been seeing will begin to chance. The northern branch of the jet stream will actually lift to the north, along the U.S. Canadian Border, and keeps the Canadian cold contained to the north. The southern, and more active branch, will break away and stay contained to the deep south. This keeps most of the wet weather contained to the south near southern California and southern Texas. This doesn't mean we won't have rain/snow chances, it means the overall wet pattern that we have been seeing will slow down. It also means that overall into January we warm up a bit, after a cold week ahead. Not a bad way to kick of the new year!

Monday Morning Weather - Updated for Evening

10:45PM Update:

The moderate to heavy steady precipitation has now lifted well to our north into Central Wisconsin. We are now seeing a few light scattered snow showers across portions of Jo Daviess, Stephenson, Carroll, Rock, and Walworth Counties. This will likely continue into the night before winding down late tonight. The good news is additional accumulations look very light, if any at all. The storm system did bring a hefty amount of snow, sleet and freezing rain to a good portion of the Stateline. Here are a few totals:

While the magnitude of these values is not all too impressive, these amounts are very high. The reason is because most of the precipitation that fell today was sleet, or ice pellets. When you talk sleet, amounts usually don't exceed an inch. With this system, plenty of moisture was available, and the vertical temperature profile of the atmosphere was just right to support moderate to heavy sleet throughout the event. Therefore, we were able to get 2-4" of sleet (with some snow mixed in) to accumulate in many areas. Sleet amounts of 1" are significant because it is all ice instead of snow, which is lighter and fluffier. When you start seeing amounts of 2" and 3", it is evident the storm system was very strong. So, while these totals do not initially look impressive, remember that they are representative of sleet with some snow mixed in. Sleet totals like these are not common as you need the perfect set up in order to get sleet to fall for such a long duration of time.

Again, the system is winding down and Winter Storm Warnings will eventually be allowed to expire for the entire region. Roads will continue to be slick and snow/sleet covered through the night with temperatures hovering around freezing. Thus, if you must venture out tonight or very early on Tuesday, make sure to exercise extreme caution.
 --------------------------------------------------------------------------------------------------------------------------

8PM Update:

 One more wave of moderate to heavy snow and sleet moving through the region this evening. The snow rates are 1-2" per hour in the heaviest bands, which have been highlighted here. Visibility is below a quarter of a mile at times within the heavy snow, and winds are blowing the snow nearly horizontal this evening. These last remaining bands of snow will continue moving north. Expect the precipitation to become light and scattered after 9-10pm from south to north across the area.

Earlier this evening we had sleet, freezing rain and snow mixing together. Now thru roughly 9-10pm we have heavy snow moving through the region. Winds will continue to be gusty out of the east northeast up to 35mph, but after 10pm, those will subside. After 10pm, the precipitation will turn very light and isolated as the area of low pressure shifts north into Northern Wisconsin. However, with the snow/sleet/freezing rain totals we have thus far, the roads will remain slick, snow-covered, and treacherous through the overnight hours. Therefore, if you don't have to be out, please don't. Many roads are extremely dangerous to be driving on tonight. Give the road crews time to clean them off, and hold off on venturing out until Tuesday, if possible.

---------------------------------------------------------------------------------------------------------------------------
5PM Update: The wintry mix is continuing across the Stateline. It is becoming lighter and more scattered as the moisture moves north. This is the "dry slot" of the storm system. More moisture is filling in to our south, and will stream in this evening in the form of freezing rain and sleet. Some areas to our south will likely remain as plain rain with some freezing rain mixing in. After roughly 9pm, expect precipitation to become much lighter and scattered in nature.

Temperatures will remain around freezing through the evening, but the upper levels will warm slightly, which means freezing rain becomes increasingly likely. The chance of freezing rain through the middle of the evening will allow for minor ice accumulations. This will lead to the potential for more power outages as power lines and tree limbs will likely become glazed in ice. If you combine even minor ice accumulations with winds gusting upwards of 35-50mph, down tree limbs and power lines become more likely.

Current wind gusts are upwards of 30-45mph. These will likely keep up through a majority of the evening. Although precipitation will become much lighter and more scattered after roughly 9pm, temperatures hovering around the freezing mark will keep the roads in bad shape, especially those that are less traveled. Plenty of roads, including US 20 are reporting nearly 75% snow and ice coverage. Therefore, it is highly advised that if you do not absolutely need to travel tonight, that you don't.

Locations shaded in the red and yellow are where current road conditions are poor. That includes the northern third of Illinois. Multiple spin-outs have been reported thus far today, and if you are traveling across Northern Illinois, the risk of more spin-outs remains in place. Road conditions will improve late tonight as road crews get a chance to catch up to the wintry mess because precipitation rates will steadily decrease. Nonetheless, using extreme caution is highly advisable through the night into Tuesday morning. A few pictures have been sent into the Weather Center of the sleet and freezing rain.
Here are a few:

This photo shows two windows covered in ice. This was a common scene across the region today as freezing rain and sleet had no issue sticking to elevated surfaces.






Roadways looked like this throughout the day as sleet, snow and freezing rain came down so heavily, it disallowed the road crews to keep up with it. Roads will continue to be ice covered through the night.

 With the powerful winds, we have seen drifts of sleet, snow and freezing rain upwards of 8-10"! This is from Roscoe. Outside of the station, we have a sleet drift upwards of 9"!






 ------------------------------------------------------------------------------------------------------------------------
2PM Update: Moderate to heavy precipitation is continuing to fall across the Stateline. The majority of the precipitation has been sleet, but snow and freezing rain have been mixing in as well. The snow is confined to areas near and north of the Illinois-Wisconsin border. The freezing rain has been just to our south thus far, but with the low pressure center continuing to push northward, warmer air is going to continue to edge its way north. That means the freezing rain will also push north into the region through the afternoon. The good news is this means our ice accumulations will be less than originally thought because we have experienced a longer duration of sleet with the colder air remaining in tact.

However, light ice accumulations up to 0.1-0.2" are still a good possibility, especially along and south of U.S. 20 where slightly warmer air has been present. Regardless of precipitation type, there are power outages being reported now across the region. Southeast Rockford has roughly 1,500 customers without power, according to ComEd. And, any freezing rain we get could cause serious issues in terms of power outages because of the strong winds gusting upwards of 50mph.

Here is a map showing the current power outages across the region. Expect this trend to continue through the afternoon into the evening with winds continuing out of the east and northeast. The other issue we have out there is ice and snow-covered roadways. This includes highways, main thoroughfares, side streets, and parking lots. The precipitation is falling at such a high rate that road crews simply are struggling to keep up. As a result, many roads--if not all--are covered with slush, which is causing accidents. If you must drive, please use extreme caution and slow down.

The City of Rockford has also stated that the Odd-Even Parking Ordinance will go into effect tonight at 7pm. A Winter Storm Warning remains in effect for the entire Stateline. For the counties of Winnebago, Lee, Ogle, DeKalb, McHenry, and Boone, that will expire at 6pm. However, the National Weather Service is considering extending that warnings because wintry weather is expected to last longer than previously thought. For all other counties, that warning goes until Tuesday morning at 6am.

Here is the latest timeline for the storm. Expect sleet, snow and freezing rain to continue to mix across the region with winds gusting to 50mph through the late afternoon. Then, as slightly warmer air in the middle levels of the atmosphere works its way in later this afternoon, we could see more in the way of a freezing rain scenario with some sleet mixing in. In fact, in our far southern areas, freezing rain and plain rain could fall late this afternoon into the evening. Then, expect precipitation to wind down and become much lighter by roughly 7pm. It will end in the southern counties first as the moisture moves from south to north. Through the evening hours, plain rain showers mixed with freezing rain is likely as a quick shot of warmer air moves in, but by this time, the precipitation will be noticeably lighter. A few light snow showers are possible overnight, but nothing significant is expected from that.

--------------------------------------------------------------------------------------------------------------------------
Noon Update: A strong area of low pressure is still tracking through Missouri and is forecasted to lift north over the Stateline through the afternoon. This deepening low pressure system is causing flash flooding through southern portions of  the state, and a wind whipped winter mix for northern Illinois and southern Wisconsin.

Currently we still have light snow mixing in with moderate bands of sleet, though there are some periods of freezing rain as well. So far through the morning we've see mainly sleet accumulate which is somewhat of a good thing, because it means our ice accumulations will be lower.

We will continue to see a freezing rain and sleet mix through the afternoon today and into the early evening as the low continues to get closer to us. This will keep the weatherisk high as we see the potential for ice to accumulate on elevated surfaces such as tree branches and power lines, as well as glazing over roads.

As winds today pick up and gust near 50mph today, widespread power outages are possible. Strong winds will also lower visibilites and have can bring down tree branches because of the added weight.

Overall, watch for ice and sleet covered roads this afternoon and evening as the winter mix continues to fall. Again, we could see near 0.25" of ice accumulate on elevated surfaces through the early evening, before our surface temperatures warm above freezing. Winds will still be breezy overnight, but won't be as strong as what we see this afternoon and early evening.







10am Update: Still tracking the snow/sleet/ and freezing rain this morning. Here are some local reports so far:
 
Marengo,IL: reports of 0.3" inches of sleet so far.
Roscoe, IL: Reports of 0.25" of sleet.
Freeport, IL: 0.10" of  freezing rain in Freeport with 1 inch of snow. Sleet accumulations of 0.50"
Milledgeville, IL 0.10" freezing rain reported and under an inch of snow.
Nora, IL (Jo Daviess): 0.5" snow mixed with sleet







7:45 Update: Band of moderate snow and sleet currently falling in the Rockford area as well as near Poplar Grove and Woodstock
 Patching freezing rain to the south.

Sleet and snow already spreading north into the Stateline - at the station as of 6:30am not noticing any precip falling - but have reports of light snow accumulation and sleet in Rochelle and Esmond according to our weather watchers. Also reports of snow and sleet in Amboy.

Storm Prediction Center released a Mesoscale Discussion about the potential for more freezing rain and winter mix precipitation today. You can see northern Illinois and southern Wisconsin highlighted in the area for a winter mix, including freezing rain, sleet, and snow fall. The greatest potential for freezing rain is nearing 7am through noon with precipitation rates near 0.05" an hour. This means we could see accumulations near .25" of ice. This is because we will have a sufficient warm layer of air up above allowing for any ice to melt and fall as rain, but then refreeze on surfaces as our temperatures at the ground are at or below freezing. Sleet - or ice pellets - are also possible.

Ice accumulations are also possible along the I-80 and I-90 corridors making driving hazardous. You can keep an eye on road conditions here.