Warmth ahead of the front

Hmmm - I wonder where the cold front is?  It's actually about ready to cross over the Mississippi River as of 11:30 am.  The colder air is lagging behind the front and once it passes by late afternoon expect temperatures to fall by this evening.

With the few breaks in the cloud cover this morning the atmosphere is beginning to destabilize just a little bit as indicated by the cumulus clouds building in the skies.  As the front moves through rain, as well as a few thunderstorms, remain likely with a start time roughly around 3pm or 4pm.  So far the activity that has been entering into northeast Iowa has just been rain with thunderstorms closer to Omaha, NE.  If there were to be any thunderstorms this afternoon the hail threat would be the greatest due to the colder air aloft.  Rain will end by this evening with the next chance arriving Wednesday night.

Temperatures tumble this week

After a gorgeous weekend a big pattern change will make the last week of summer feel anything but that.  A strong cold front stretching from northern Wisconsin southwest through Rochester, MN to Sioux City, IA this morning will quickly race southeast this afternoon.  Cloud cover has been increasing ahead of the front and is expected to continue into the afternoon.  Showers, with a few embedded thunderstorms, have been developing just behind the front as a very strong jetstream helps to carve out a trough of low pressure in the northern Plains.  The rain will likely maintain itself through the afternoon and evening due to the strong jetstream despite the lack of sunshine we're currently experiencing.  Behind the front very cold air will filter into the Plains and Midwest beginning tonight with temperatures in Minnesota and northern Wisconsin expected to plummet into the upper 20s/low 30s.  That cold air will be in our neck of the woods Tuesday night as a surface high pressure system moves in overhead.  The center of the high is expected to be almost overhead once the sun sets Tuesday and this will likely set the stage for temperatures to nose dive into the upper 30s before an increase in cloud cover arrives by daybreak Wednesday.  Right now I'm forecasting a low temperature of 37° which is just three short degrees away from the record low of 34° set back in 1929.  It's also possible that patchy frost could develop Tuesday night with the greatest potential to the north where temperatures will likely be the coldest.  On average, the first frost usually occurs within the first week of October usually around the 10th (give or take a few days).  Is it certain that there will be frost, no.  But it's something to keep in mind for Tuesday. 

The afternoon on Tuesday will also be cold with the high temperature only expected to be right around 60°.  Highs will remain cool this week as a series of cold fronts move through; the first today, the second on Wednesday and the third Thursday night.  As each front passes it will continue to pull down a cool air mass just in time for the weekend.

A Pattern Change This Week

The last weekend of summer proved to be a fabulous one.  There was lots of sunshine, and temperatures reached the low 80's on Saturday and the upper 70's on Sunday.  A strong cold front is approaching from the northwest tonight, and will pass through the Stateline around noon on Monday ushering much colder air into the mid west.   In advance of the cold front tonight, clear skies will slowly become partly cloudy.  It will not be a cool as the last two night's with a low around 55 degrees.  Monday will be mostly cloudy, and there could be some scattered showers in the morning.  There is no gulf air available for the front to work on, so rain amounts are expected to be relatively light... around 0.25" or so.  There could be an isolated thunderstorm or two with the passage of the front because of unstable conditions with very cold air aloft with the passage of the front.  High temperatures around 73 degrees will occur around noon, the wind will switch to the northwest at 10-20 mph, and temperatures will fall during the afternoon as colder air follows in behind the front.  Some scattered light showers could linger until around midnight, skies will become  partly cloudy, and it will be colder with a low in the low 40's.  A large area of Canadian high pressure will be  centered near Sioux City, Iowa by 6 am on Tuesday.  A brisk northwesterly wind will hold temperatures in the 50's for most of the day under sunny skies.  The high temperature may reach 60 degrees in Rockford on Tuesday afternoon.  It will be clear and cold on Tuesday night as the high pressure  moves to near Quincy, Illinois by 6 am Wednesday morning.  With the core of the cold high very nearby, clear skies, and light winds, there will be maximum radiational cooling during the night dropping temperatures across the Stateline into the middle 30's, which is likely to cause some early season patchy frost.  Any frost that does occur will likely be in low lying rural areas, but may edge into some small cities.  Full sunshine during the morning will cause a nice rise in temperatures, and by afternoon it may be as mild as 68 degrees in the Rockford area.  There will be an increase in clouds by late in the afternoon as the next system dropping down in the fast northwesterly upper air flow approaches the Stateline.  Scattered showers may develop on Wednesday night in advance of the front.  The low will be in the low 50's. The next cool front will sweep across the area early on Thursday morning, and there could be some scattered light showers on Thursday.  Another front will move into the area early on Friday with a good chance of more light rain showers. Temperatures will drop to the mid 40's for overnight lows next weekend, and rise to the middle 60's.  Below average temperatures area expected to continue for the rest of September.

Fabulous Sunday... Then It's All Downhill into Fall

High pressure was the weather maker over all of the mid west today from a center over Illinois. There was full sunshine, low humidity, light winds, and very comfortable temperatures. The high temperature in Rockford reached 81 degrees. It will remain clear overnight with a low around 50 degrees. The center of the high will move east to West Virginia by 6 am on Sunday, but it will ridge back into Illinois and continue to dominate area weather.  So, Sunday will be sunny again with a southwesterly wind picking up to 10-15 mph in the afternoon. The temperature will reach the low 80's. with blue skies and low humidity.  Sunday is my pick day of the week.  It may be a while until we see 80 degree temperatures again with a pattern change taking place this coming week that will sweep a strong cold front across the Stateline during the mid day hours on Monday.  There is not a lot of moisture for this next system to work with, but right now it looks like there will be enough to make showers and possibly some thunderstorms.  Rainfall amounts are expected to be fairly light (around 0.25").  So this next system will not do much to put a dent in the extreme drought across northern Illinois.  Temperatures will top out in the low 70's before frontal passage on Monday.  It will be breezy and cooler with falling temperatures on Monday afternoon.  A couple of showers could linger into Monday evening, followed by gradual clearing.  It will be much cooler with a low in the low 40's.  It will be breezy with  a brisk northwesterly wind on Tuesday. Temperatures will not recover much , and may have a hard time reaching beyond the upper 50's for afternoon highs. With the ridge of Canadian high pressure overhead on Tuesday night, skies will be clear, and winds will be light, allowing for strong radiational cooling dropping temperatures to the coolest levels so far this season.  The overnight low into early Wednesday morning will be in the upper 30's with the possibility of some patchy frost in scattered low lying areas of south central Wisconsin just to the north of Rockford.

Fabulous Weekend!

Canadian high pressure was responsible for the sunshine, low humidity, blue skies, light winds, and comfortable temperatures across the Stateline on Friday.  The high was 75 degrees in Rockford, and that was just 1 degree below average.  The sprawling high will edge slowly eastward across the area overnight, and it will be centered just to our east on Saturday.  It will provide the Stateline with another sunny day on Saturday, and yet another on Sunday.  The afternoon temperatures will reach the upper 70's to around 80 degrees both days.  It will be comfortable with low humidity, but by Sunday afternoon the wind will pick up from the southwest at 10-15 mph.  A new cold front will approach the area on Monday morning.  This front is a strong one with significant cooling following in behind it.  There will be a good chance of showers associated with the frontal passage, and maybe even an isolated thunderstorm.  It will be cooler with the high temperature around 69 degrees occurring in the morning, and temperatures falling into the upper 50's or low 60's by late afternoon.  There could still be some scattered showers in the evening.  It will be breezy and cooler overnight with an early morning low around 43 degrees.  Canadian high pressure will follow in behind the front dropping temperatures to around 40 degrees on Tuesday night.  There will be a relatively fast northwest flow across the northern plains into the upper mid west, and the next cold front will already drop across northwestern Minnesota across southern South Dakota by 6 am on Wednesday.  Our area will see a bit of a warm up with the afternoon highs reaching close to 70 degrees.  There will be a slight chance of showers late in the day, and a better chance on Wednesday night as the front pushes through the Stateline.  Temperatures will remain cool through Friday with highs in the 60's and lows 45 to 50 degrees.

Summer heat fading away

We're beginning to enter into the season where large temperature swings will become more common; chilly mornings but warm afternoons.  As September begins to come to a close the likely hood of us reaching another 90 degree continues to fade, along with the frequency of 80 degree weather.  We lose 10° from the beginning of the month to the end of the month with the average high and it appears as if the cool trend will continue into next week. 

The weekend looks absolutely gorgeous with comfortable afternoons as high temperatures reach the middle and upper 70s.  Overnight lows will be chilly making this weekend the perfect 'cuddle up' weekend.  By next week a strong cold front will sweep down from Canada Monday night bringing with it the threat for rain but also much cooler weather.  Temperatures next week look to only reach the middle 60s on Tuesday and with the jetstream pattern remaining in place the cooler weather may even continue for the end of the month.

Football Forecast Looking Dry

It's only the second week of the NFL season, but there couldn't be a bigger game than the Bears and Packers matchup tonight.

Fortunately, the forecast should cooperate for tonight's game. Look for clearing skies through the game (more importantly, no rain!) and chilly temps. Temps around kickoff will be in the upper 50s, cooling into the upper 40s by the end of the game.