Rain showers follow unseasonable warmth Thursday

 

For the third day in a row the high temperature warmed into the 40s, with Rockford's high reaching 47 degrees Wednesday afternoon. Temperatures will climb even further Thursday as a strong southerly wind takes hold, likely bringing the majority of the Stateline into the low 50s. South winds will gust close to 30 mph during the afternoon.

For the remainder of Wednesday evening skies will stay clear as temperatures drop back through the 30s, down into the upper 20s overnight. Winds will remain light as they shift to the south Thursday morning.

Thursday starts with a little bit of a chill, but temperatures will warm quickly during the afternoon. Highs will reach the low 50s, and possibly mid-50s, especially if cloud cover can hold off through most of the afternoon ahead of our next storm system. If clouds move in sooner temperatures would likely fall short of the 50-degree mark. The record high for the 30th of January is 52 degrees set back in 2012. The current forecast high is 53.

The arrival of the cloud cover during the afternoon and evening and will also come with the chance for rain. Rain showers will increase in coverage from south to north, moving into the Stateline Thursday evening. The exact amount of rain is still a little uncertain due to thunderstorms that'll be ongoing in the South. These storms could limit the overall amount of moisture into the region, limiting some of the higher rainfall totals. But it's likely that at least a quarter of an inch, if not close to half an inch, will fall through Friday morning. While this may not seem like a lot the frost depth is still rather deep in the ground and despite the warmer temperatures, little thaw has taken place. This would lead to more rain runoff into some of the local rivers, creeks, and streams rather than the rain soaking into the ground. River levels and the potential for ice jam flooding will be closely monitor from Friday through the weekend as a result.

Temperatures remain mild Thursday night before a slightly cooler air mass settles in Friday morning. This could lead to the potential for some snow to mix in with the rain, or even a short duration of all snow Friday morning. Little to no snow accumulation is expected at this time, but if temperatures trend slightly cooler for Friday morning, then we could see some impacts with the wintry weather. Highs on Friday will warm into the low 40s. 

Staying unseasonably mild ahead of our next storm system

Plenty of sunshine, along with the influence of gusty southwesterly wind, allowed spring-like temperatures to surge in for a second consecutive day.

Officially, Rockford peaked at 49°, which comes 20° above late-January standards. Temperatures stay mild for Wednesday, though won't be as warm as a cold front did come through overnight. 

Similar to Monday and Tuesday, a good mixture of clouds and sun is likely. Instead of winds being out of the southwest, we'll have a northwesterly breeze in place, which at times could gust up to 30 mph. This will bring temperatures down a few degrees, landing afternoon highs in the low 40s. Again, unseasonably mild. Skies remain quiet and partly cloudy overnight, with low temps falling into the upper 20s.

Ahead of our next system, winds swap back to the southwest for Thursday. This will allow afternoon highs to climb back towards the 50° mark. At the same time, clouds will increase as said storm system lifts northeastward out of the southern plains. Wet weather is soon to follow, with scattered rain showers sliding in Thursday evening. As colder air wraps in around the low's center, we could see snowflakes mix in during the first half of Friday.

Ice jam flooding possible with recent warmth and late week rain chance

 

The recent cold spell allowed quite a bit of ice to rapidly develop on some of the local rivers resulting in significant ice coverage over the last week. The warmer temperatures this week, and possible rain chances late in the week, may cause water levels on the rivers to rise - especially Friday and the weekend.

Temperatures Monday and Tuesday warmed into the mid and upper 40s, with 40s and likely low 50s expected Wednesday and Thursday. An incoming storm system from the southwest will move across the country into central Illinois late Thursday and Friday. To the south, severe weather will be likely in the southern Plains and Gulf states, while scattered rain showers (perhaps with some rumbles of thunder) occur in parts of the Midwest.

A period of light rain and drizzle will develop late in the day Thursday as low pressure tracks near or just north of St. Louis, MO before moving into central and northern Illinois Friday morning. While it's a little unclear at the moment just how much rain will occur, due to the impacts of moisture transport from storms down south, rainfall totals across at least a portion of northern Illinois could approach a quarter of an inch. 

While that may not sound like much, the current frost depth measured Tuesday morning was nearly a foot with little to no surface thaw being reported just yet. It's likely with the milder weather that there will be some thaw through the week, but it won't be deep enough to allow any rain that does occur to soak in which could lead to runoff into the local rivers. Not only would this cause a rise in some of the local river levels it could also cause further breakup and dislodging of river ice, leading flooding concerns due to ice jam flooding.

At this moment the risk is still low but something that will be monitored throughout the week. Those who live along the local rivers should continue to monitor the forecast and be prepared should there be rapid fluctuations in river levels.    

Second afternoon in a row where wind gusts could approach 50 mph

Winds were howling Monday, though thankfully these were very warm winds. This left afternoon highs in the mid-40s which is typically what we see average-wise in mid-March. The Stateline is in for a similar scenario today, with an organized warm wind resulting in a spring-like afternoon. 

Winnebago, Boone, McHenry, Ogle, and DeKalb Counties will be under a WIND ADVISORY from 2PM-6PM. Walworth County up in southeast Wisconsin will also be under a wind advisory, though the advisory starts an hour earlier. 

 

 

Those under the advisory will likely see winds peak between 45-50 mph. Winds this strong can make driving difficult, especially for those who operate a high profile vehicle. Fire danger will also be elevated so use extreme caution when disposing of smoking products. Also, postpone burning until another day. Similar to Monday, these organized winds will bring afternoon highs into the upper 40s, but chills will feel about 10° colder thanks to the strength of the wind. Cloud cover will start the day but then quickly clear as drier air moves back in. 

Forecast models then show another quick moving system sliding across the Midwest overnight, pulling another cold front through. This will come through dry, though winds will switch to the northwest. Afternoon highs Wednesday won't be as warm but still mild close to 40°.

Strong winds ease Monday evening, but pick back up Tuesday

 

Southwest winds were rather strong across the region Monday prompting the issuance of a Wind Advisory for a portion of the viewing area until 6pm. Wind gusts were close to 50 mph in a few locations, including Rockford. The wind advisory will expire at 6pm as the strong wind gusts are expected to ease some through the evening, however, remain close to 25-30 mph through the night.

The wind direction will briefly turn to the northwest through the night following the passage of a weak cold front. This front has brought an increase in cloud cover to the region with a few light radar returns showing up. However, given the extremely dry air mass in the low levels very little precipitation is expected to reach the ground. If we were to see anything it would be a light sprinkle or flurry late this evening. A warm front will then be quick to move in Tuesday shifting winds back to the southwest and bringing temperatures back into the mid and upper 40s.

Stronger winds aloft will once again move through the Midwest causing surface winds to gust around 40 mph Tuesday afternoon. Similar to Monday, this will bring afternoon temperatures into the mid 40s, but chills will feel about 10 degrees colder thanks to the strength of the wind. Cloud cover will start the day but then quickly clear as drier air moves back in. This will leave skies partly cloudy through most of the afternoon. Another quick moving system will slide across the Midwest Tuesday night pulling another cold front through. No precipitation is expected. Winds will remain from the northwest during the day Wednesday, but little cooling will take place. Highs on Wednesday will warm close to 40 degrees.

  

Wind Advisory with gusts as high as 50 mph possible Monday

Last week, a potent blast of polar air left the Stateline struggling to climb above the 0° mark. This week, it's the complete opposite as afternoon highs look to wind up roughly 35° to 40° warmer. How is this possible? Strong southwesterly winds. 

In other words, it will feel MUCH more comfortable outside, you just won't be able to enjoy it as much with such a strong wind in place. 

A WIND ADVISORY will be in place for Winnebago, Boone, McHenry, Ogle, Lee, and DeKalb Counties in northern Illinois from 9AM to 6PM. Walworth County up in southeast Wisconsin will be under the wind advisory from 8AM-6PM.

Those under the advisory will likely see winds peak between 45-50 mph this afternoon. Winds this strong can make driving difficult, especially for those who operate a high profile vehicle. Elsewhere, peak gusts could still reach 35-40 mph. These winds will force considerably warmer air into the Stateline, leaving high temperatures in the mid 40s. There will be plenty of sunshine to start, though cloud cover will start to build in during the afternoon. 

 

Overnight, a backdoor cold front will sink down into the Great Lakes, shifting our winds briefly to the northwest. Forecast models suggests there may be a few flurries with said cold front, though we may have to see if these flurries can fight off dry air. If not, then we won't see much if anything. Low temperatures will land in the mid 20s with clouds gradually clearing followed the cold front.

Period of strong winds possible Monday, wind advisory issued

 Monday will be a windy day across the Stateline, with some areas now seeing a wind advisory in place. Winnebago, Boone, McHenry, Ogle, Lee, and DeKalb Counties in Illinois will see that wind advisory run from 9AM to 6PM Monday, while Walworth County in Southeastern Wisconsin begins at 8AM and runs to 6PM.

The strongest of the wind gusts will be focused on the Northeastern portions of the viewing area, hence the limited coverage of the wind advisory. Those within the orange shaded area, from Monroe, WI down to Dixon, IL and areas East have the strongest potential to see peak gusts near 45 mph or greater out of the West-Southwest or Southwest. Elsewhere, peak gusts could still reach 35-40 mph. The time frame of the strongest winds looks to arrive by early afternoon.

Southwest or WSW direction of these strong winds will heavily dictate temperatures for the next couple of days. Monday and Tuesday could see afternoon highs reach well into the 40s, especially if we see more sunshine than cloud cover. Wednesday will also be breezy, with peak gusts near 20-30 mph, but this time from the Northwest. That will bring a brief cool-down with highs returning to the 30s.

One of the reasons for the strong winds is due to a feature called atmospheric mixing. This is when the air masses often mix down to the surface, drawing some portion of the wind speeds with it. In this case tomorrow, we will have strong winds of around 60 mph only a mile or so up in the atmosphere. The mixing down of those winds is what will bring 40-45 mph gusts to the surface. The more sunshine we see, the less cloud cover there is to block that mixing from occurring. Therefore, more sunshine can lead to warmer surface temperatures and in this case, stronger winds.

Though we will remain windy over the next couple of days, our precipitation chances are limited. Along a weak cold front Monday afternoon, we may see a few sprinkles or flurries try to work toward the surface, but these would be very light and scattered in nature if we see anything. There is a similar trend for a precipitation chance Wednesday morning, but widespread chances could return late in the week.