Comet seen once every 80,000 years to appear across northern Illinois skies

Days after the northern lights were visible across Stateline skies, another rare astronomical event is underway. 

Comet Tsuchinshan-ATLAS, also known as C/2023 A3, is expected to be visible to the naked eye across the Northern Hemisphere into the end of October according to NASA. 

This is a once in a lifetime event considering the comet’s orbit around the sun is once every 80,000 years. To find comet C/2023 A3, look west about 45 minutes after sunset. This comet is expected to get higher in the sky and dimmer with each passing evening. 

Having a pair of bincolars or a DSLR camera with a zoom-in lens will further make things easier to view the comet. Unlike the last few days, today and the days that follow feature better viewing conditions as cloud cover won't be as expansive. 

Freeze warning expanded to include all of northern Illinois

A FREEZE WARNING has been issued for all of northern Illinois and southern Wisconsin. This will run from 1AM-9AM Wednesday as temperatures look to fall into the upper 20s and low 30s. 

Based on climatological data, this lines up well with Rockford's average first fall freeze which typically occurs near October 13th. Before heading to bed this evening, make sure your sprinkler system and your hoses are taken care of to avoid damage. Cover up fragile plants that may be susceptible to the freeze with a light linen blanket or move them into a garage or shed if they’re potted plants.

Temperatures remain seasonably cool for Wednesday thanks to a chilly but light northwest wind. Expect afternoon highs to peak in the upper 50s. Though not as widespread, frost will be likely Wednesday night as temperatures land near the 32° mark. 

 

This crisp, November-like air is scheduled to say adieu, aufwuedersehen, gesundheit, farewell (Willy Wonka quote) by Thursday as afternoon highs make the climb towards the 70° mark. 

Southwest flow and extremely dry conditions will remain in place into the weekend, allowing highs to climb further from average. Expect low 70s Friday and Saturday, then upper 70s Sunday.

Fall frost/freeze expected Tuesday night

 

It looks like our first Fall frost/freeze will take place Tuesday night as skies clear from any cloud cover and the gusty winds we've experienced the last few days subside.

A FREEZE WARNING has been issued for our northwest Illinois counites of Stephenson, Jo Daviess, Carroll, and Whiteside. A FREEZE WATCH is currently in place for Green and Rock counties in southern Wisconsin, and for Winnebago, Boone, Ogle, Lee, McHenry, and DeKalb counties. For both, these will go into effect Tuesday night, lasting through Wednesday morning.

Temperatures Monday night will likely dip into the upper 30s for most, but a gusty northwest wind and cloud cover will limit the overall potential for any widespread frost. It's possible there will be some patchy frost, especially where skies clear through the night, but widespread frost is not expected.

Tuesday will start mostly cloudy as northeast winds help pull cloud cover in off of Lake Michigan. A few spotty showers may also be possible east of Rockford. As high pressure settles in closer to the Mississippi River Tuesday evening skies will continue to clear, leaving mostly clear skies Tuesday night. Gusty winds from earlier in the day will ease as lighter winds remain in place Tuesday night. This will allow temperatures to fall quickly once the sun sets, dropping into the upper 20s and low 30s. The clear skies and light winds will allow for widespread frost to develop through Wednesday morning. Wednesday night will hold another chance for frost and freezing temperatures before temperatures climb back above average by the end of the week. 

November-like chill to bring northern Illinois it's first freeze of the season

Get ready folks! The coolest air of the season thus far has arrived and it will likely result in our first freeze of the season in the nights ahead. 

Freeze warnings are currently in place across the Upper Great Plains as some are waking up the upper 20s. Temperatures locally are too warm for frost or freeze alerts, though chilly enough for a thicker coat as the day begins in the low 40s. 

Today is going to mark the first day since April 24, where highs will peak below 60 degrees. A cool northwesterly wind as well as a good deal of cloud cover will limit afternoon highs to the low 50s. This is what we typically feel in early November, not in the middle of October. Along with today's cloud cover will come the chance for an isolated shower, mainly along and east of I-39. That, as well as the cloud cover will linger into early Wednesday, with lows falling into the upper 30s.

Clouds move out for Tuesday, though a stronger and cool northerly wind will be in place. This will once again limit highs to the low 50s. The bigger headline however comes in Tuesday night into Wednesday as the Stateline's first freeze is likely. 

Temperatures into Wednesday are expected to rapidly fall into the upper 20s. For that, the National Weather Service has placed our western counties (Stephenson, Jo-Daviess, Savanna, and Carroll) under a Freeze Watch. If you have any sensitive plants, you may want to cover them or take them inside Tuesday evening before heading to bed. Temperatures Wednesday night will also be capable of reaching the freezing mark.

Chilly fall-like stretch settles in through mid-week

 It was a downright blustery day in the Stateline Sunday with wind gusts nearing 40 mph at times. Temperatures only briefly reached the low 60s, but much of the daytime hours were spent in the 50s. This is much more like late-October than early October!

That cool stretch lasts a few more days, with high temperatures only reaching the mid-50s Monday and Tuesday with continued cloud cover and even some isolated showers Monday afternoon and evening. Wednesday brings some frost early on, but more sunshine by the afternoon.

With very cool air and an upper-level low spinning up to our North, we may see a few of those isolated showers close by Monday afternoon and evening. Best chances look to be in Southern Wisconsin and East of I-39. Whatever rain does fall will not amount to much, with less than 0.1" for most.

Cool afternoons translate to downright cold overnights, with many low temperatures in the 30s this week. We have a good chance to see our first frost of the season Tuesday or Wednesday night, with overnight lows in the low 30s and light winds with high pressure overhead.

If these cool days are making you think of the changing leaf colors, I have good news! Typically, the area sees peak fall colors around mid to late-October, so we should be seeing those colors become more vibrant over the next week or two! One of our weather watchers, Ed sent us this picture of some colors peeping from near Dixon! If you want to send us your fall photos to get featured on air, send them via the First Warn Weather app!

Luckily, the cooler stretch doesn't last very long, as surface and upper-level winds flip to come from the South and Southwest mid-week, returning high temperatures to the 60s and low 70s through next weekend.

First freeze of the season possible this week

 It has been an abnormally warm stretch across much of the country to start the fall season, with many days seeing highs well into the 80s. But some big changes are on the way, as cooler air from the North will surge over the Great Lakes region over the next few days.

The initial push of cooler air comes with strong winds from the Northwest especially Sunday afternoon. Winds could gust to 35 mph at times, making for a downright chilly and windy day.

High temperatures the next few days in Rockford will be well below average, only reaching the 50s and low 60s through mid-week. It will be a cool and windy day Sunday with isolated showers and highs in the low 60s. Monday and Tuesday are cooler with highs only in the 50s, but gradually drier conditions develop with high pressure moving in.

That high pressure will also limit the winds for a few of the overnights. This will allow for at least patchy frost if not a legitimate freeze some nights. On average, Rockford sees its first fall freeze October 13th, so we won't be too far off that. Tuesday night will be the coolest overnight low with the core of the high pressure directly overhead. Many locations in Northern Illinois will see similar temperatures, outside of Chicago in their urban heat island. Be sure to have a plan to protect any sensitive plants or vegetation this week!

Fall approaching with cool and windy stretch coming

 

With yet another day above average temperatures across the state line many fall enjoyers are still looking for that first sweep of cooler weather. For those who enjoy fall you don't have much longer to wait as our first true fall stretch of weather looks to come this weekend into early next week.

Starting with today, we'll be cooler than yesterday as the passage of a cold front overnight helped drop temperatures near normal for mid-October with today only expected to get to the upper 60's. Along with that breezy conditions behind the cold front will help temperatures feel a little cooler through the afternoon. There is still the chance of an isolated shower or two throughout the state line all depending on how dry the surface conditions are. 

Isolated shower conditions will stick around through much of the day with the highest chances being this evening. As of now the one concern is the moisture in the atmosphere as we've very dry with dewpoints only in the mid 40's today with our surface temperature being in the upper 60's. Anyone shower that does occur today don't expect considerable rain as they will be a quick little sprinkle at most which won't do anything for our already dry conditions.

One thing will be guaranteed though as wing gusts behind the cold front from yesterday will be peaking near 25 mph today. Expect windy conditions to stick around through the week as upper-level low pressure and stronger upper-level winds will help increase wind speeds as well as bringing in cooler air.

Taking a look at temperatures at 850 millibars or just less than a mile above the surface of the earth, the clear dome of cold air dominates the entire Midwest through the beginning of the week. With cold low pressure centered over the Great Lakes much of the Midwest will feel cooler Canadian air being brought in. The nights will be especially cold, as previously mentioned with very little moisture not even cloud cover will stick around through this time. With cool nights temperatures will drop even more which may be enough this week for our first frost development of the season!

Through the early parts of the week temperatures will begin to drop to normal and even below normal temperatures for this time of year. After weeks of above average temperatures some cool down looks likely for all the people who love fall! With temperatures dropping into the 30's and even near freezing Monday and Tuesday night frost looks likely. Besides cooler temperatures though, dry and breezy conditions will stick around through the week until next weekend where warmer conditions and better precipitation chances look possible!