Thursday, June 27, 2019

Hot Nights and Warm Days are Often a Dangerous Combination

Heat becomes more dangerous when it lingers for more than one day. That's because the combination of hot days and warm nights doesn't allow our bodies time to cool down, which typically occurs at night. But if the temperature at night remains warm and muggy, we get very little relief from the heat.

Overnight lows through the weekend are forecast to remain in the low 70s straight through Sunday night. This comes after highs warm into the low 90s, with a heat index in the mid/upper 90s. Heat islands, such as large cities, can also intensify extreme heat and are often times the reason why nighttime lows don't cool off as much. It's especially dangerous for those who are more sensitive to the heat such as the elderly, children and those with health issues.

High temperatures through the weekend will warm into the upper 80s and low 90s but the heat index, especially for Saturday and Sunday, could warm into the mid and upper 90s. If you are going to be outdoors for any period of time it's important to remember to take frequent breaks in the A/C, wear light weight, light colored clothing and drink plenty of water. Be sure to check on your neighbors who are elderly or don't have air conditioning. And don't forget your pets, too. They get hot just like we do. Make sure they have plenty of water to drink and be sure to protect their paws on the hot asphalt and concrete.

NEW: Severe Thunderstorm Watch Issued for Parts of the Area

Severe Thunderstorm Watch canceled for Lee and DeKalb counties. 

The severe threat has pretty much ended for much of northern Illinois and southern Wisconsin, although there will still be a few showers and perhaps an isolated storm through the evening.  Most of the severe weather remain north in Wisconsin with numerous reports of wind damage and power outages.

The severe thunderstorm watch has been canceled for most except for Lee and DeKalb counties.

NEW: Severe Thunderstorm Warning for southeast Lee County and DeKalb County until 6:15pm. The storm is located over Paw Paw and moving east at 15 mph. Wind gust to 60 mph and quarter sized hail possible.

 5:50pm Update: Thunderstorms continue to bubble up over DeKalb, Lee and Ogle counties, likely a result of an outflow boundary that came through earlier in the evening.  While not severe at the moment, these storms will be capable of heavy rain and strong winds possibly up to 50 mph.

5:20pm Update: Half inch hail and wind gusts to 50 mph possible with the storm moving into Boone County

NEW: Severe Thunderstorm Warning issued for Rock and northwest Walworth counties.  Storms moving through Green County continues to move east & is capable of 60 mph wind gusts and small hail.

A Severe Thunderstorm Watch has been issued for Stephenson, Jo Daviess, Carroll and Green counties until 7pm Thursday evening.  A line of thunderstorms continue to move east/southeast from Minnesota into Wisconsin Thursday afternoon.  The overall line has weakened slightly but will be moving into an environment that has quite a bit of energy and instability.  While a couple severe thunderstorm warnings are present, it's possible this line could re-intensify as it moves into southern Wisconsin and far northern Illinois.  If so large hail, damaging winds and very heavy rain would be the primary concerns.

Most of the storm activity will remain along and north of Highway 20, however, further development southward is possible as storms move into southwest Wisconsin.

Heat Index to Reach 90 Degrees for the First Time this Season

Temperatures and heat index readings in the 90s are not something uncommon in northern Illinois and southern Wisconsin during the summer months, but the first time it happens is usually a little bit of shock to the body because we're not used to that kind of warmth and humidity.  Temperatures will warm into the upper 80s through the weekend but with dew point temperatures in the low 70s, the heat index will warm into the low to mid 90s.

A strong ridge of high pressure will build over the center of the U.S. Wednesday and Thursday, shifting northeast into the Midwest and Great Lakes by Friday and Saturday.  As the jet stream lifts north, scattered thunderstorms will be possible as disturbances move through the flow of the jet stream.  As moisture is pulled north under the ridge dew point temperatures will also warm.  The dew point temperature is a direct measurement of how much moisture is in the atmosphere.  Whenever the dew point temperature rises over 65 degrees, it's considered to be fairly
muggy.  Dew points by the weekend are expected to reach the low 70s.

With the returning moisture, however, will also come the chance for isolated thunderstorms for the weekend.  The placement of the jet stream will be key in exactly where thunderstorm development will occur.  A pattern very common during the summer months is often times called the 'ring of fire' pattern.  Sinking air under high pressure heats the atmosphere fueling thunderstorms that ripple through the jet stream around the heat dome.  If the outer edge of the jet stream lines up across the Great Lakes it could put parts of Wisconsin and Illinois in the more favorable area for thunderstorm development.  If it doesn't, then we'll have more of an influence from the sinking air possibly rising temperatures into the low 90s through the weekend.

Either way it's going to get a little more uncomfortable as the week progresses.  If you plan to spend a lot of time outside later this week just remember to take frequent breaks as the humidity increases. 

Tuesday, June 25, 2019

Tuesday Afternoon Weather Update

The Severe Thunderstorm Watch has been canceled for northern Illinois and southern Wisconsin. Any thunderstorm activity will remain mostly south of the immediate area Tuesday evening.

A Severe Thunderstorm Watch has been issued for Winnebago, Boone, McHenry, Ogle, Lee and DeKalb counties in Illinois and for Rock and Walworth counties in southern Wisconsin until 9pm this evening.

There was a severe thunderstorm warning for Rock County earlier Tuesday afternoon but that warning has since expired.  Thunderstorms continue to move just north of Rockford this
afternoon, with isolated storm activity likely through early evening.  Overall storm coverage will remain very isolated but any storm that does develop will be capable of quickly turning strong to severe.

Monday, June 24, 2019

Strong Storm Possible Tuesday Evening

While not a guarantee Tuesday, there is a chance for strong thunderstorms once again Tuesday evening as an upper level disturbance moves through the Midwest and Great Lakes. 

A cold front passing through the Stateline Monday evening brought with it showers and thunderstorms, most remaining below severe limits.  Behind the front is a slightly drier air mass but dew points Tuesday afternoon are forecast to reach the mid 60s once again. This moisture in the atmosphere could help fuel a few thunderstorms as the disturbance works in from Iowa late in the evening. The overall risk for storms is low but any storm that can grow strong enough would have the potential to produce quarter sized hail and wind gusts to 60 mph. Heavy rainfall would also be a threat with any thunderstorm.

Monday Afternoon Weather Update

7:00pm Update: Scattered thunderstorms moved through southern Wisconsin and northern Illinois late Monday afternoon and evening producing heavy rainfall, frequent lightning and gusty winds. Most of the storm activity has shifted to the east over Lake Michigan, but a few scattered storms continue to rotate around low pressure in southern Wisconsin. As they rotate to the east and southeast, isolated storms will be possible through 9pm with skies turning partly cloudy overnight.

The overall severe threat has greatly diminished this evening with any stronger storms likely producing mostly small hail and heavy rain. There does remain a risk for stronger storms again Tuesday evening with the passage of another boundary/surface trough late in the day. Hail and wind would be the primary weather concerns during that time.

5:45pm Update: The line of thunderstorms has pushed east of the immediate area with skies turning partly cloudy this evening.  Additional thunderstorms continue to rotate around low pressure and are currently moving through southwest Wisconsin, keeping the storm chance through about 8pm/9pm this evening.  Skies will then turn partly cloudy overnight.

 3:30pm Update: The storm moving into northwest DeKalb County has had a history of producing torrential rain and winds in excess of 40 mph.  A couple of our Weather Watchers have reported very heavy rain and strong winds as the storm moved through Esmond and the Fairdale/Kirkland area.

Additional thunderstorms have moved into northwest Illinois and will also be capable of

very heavy rain, frequent lightning and strong winds.

A Severe Thunderstorm Warning has been issued for southwest Whiteside County until 4:15pm Monday afternoon.  Storms located over eastern Iowa have had a history of producing strong wind gusts.  These storms are moving east at 35 mph with the greatest threat quarter sized hail and 60 mph wind gusts possible.

Additional thunderstorms are also moving across northwest and north-central Illinois.  Those
storms are not currently severe but are capable of heavy rainfall and frequent lightning.  There does remain a slight risk (area outlined in yellow) for strong to severe storms Monday as a cold front works across Wisconsin and Illinois.  Greatest threat with the storms will be hail, followed by strong winds and heavy rain.  Most of the storm activity should be done around sunset.

Sunday, June 23, 2019

Isolated Showers Likely Sunday Evening

 7:20pm Update: Starting to see rain activity become a little more widespread this evening across northern Illinois.  Greatest concern will be heavy downpours.

Most of the shower and storm activity has been focused to the east and southeast much of Sunday afternoon, tied to an area of better instability across northern Illinois.  However, a few isolated showers have developed Sunday afternoon will continue as a cold front and low pressure system move closer to the Stateline.

The warm front that brought overnight storm
activity to much of the area lifted north into Wisconsin providing a better focus for storm development to our north much of this afternoon.  Very little forcing will take place in the atmosphere overnight to really provide much for thunderstorms to develop on, so most of the night should remain dry.

As a surface low pressure system and cold front move closer to the area Monday afternoon, thunderstorm activity will become more widespread mid to late morning and afternoon.  There remains a low risk for strong to severe storms over northern Illinois and southern Wisconsin Monday afternoon.  Greatest concern would be mostly hail should any strong storm develop. 

Thursday, June 20, 2019

Storm Chances Increase for the First Weekend of Summer

Summer officially begins Friday at 10:54 am and with the official start of Summer will come the threat for showers and thunderstorms, some of which could produce heavy rainfall and strong to severe storms. Friday morning will start dry but increasing cloud cover will occur mid to late morning.

A complex of thunderstorms will be moving in from the west but will be weakening as they
move across Iowa. It does look like they'll hold together long enough to bring a shower/storm chance to northern Illinois and southern Wisconsin after Noon. No severe weather is expected at that time.

Skies will then dry going into Friday evening before another complex of thunderstorms develops to the southwest Friday night. Those storms will lift northeast by Saturday morning
into northwest Illinois. A warm front will be located southwest of the Stateline during the day Saturday and will be the focus for thunderstorms during the afternoon. As the warm front begins to lift into the Stateline Saturday evening, the chance for showers and thunderstorms will increase late Saturday.

Several disturbances will move through the Midwest Sunday afternoon and evening. Strong to severe storms will be possible during that time, but then again Monday as low pressure moves into northern Illinois.

Increasing moisture over the weekend will also lead to the potential for heavy rainfall with rain totals over one to two inches. The weekend won't be a complete washout, but if you do have any outdoor plans make sure you pay attention to the forecast and have a backup plan should storms move through.

Wednesday, June 19, 2019

Steady Rain Continues Wednesday Night

Light showers dotted the sky through much of Wednesday morning and early afternoon, but the rain has become more widespread and steady Wednesday evening. Pockets of more moderate rain will be likely over the next couple of hours as low pressure moves into central Illinois. Heavier rainfall has been occurring over much of central and east-central Illinois, closer tied to the low pressure system.

Rainfall totals have been on the lighter side with less than a quarter of an inch coming down so far. An additional quarter of an inch, up to half an inch, will be possible before the rain ends Thursday morning.

Tuesday, June 18, 2019

Rain Showers Return Wednesday

An approaching cold front Wednesday morning will bring with it an increase for showers, and isolated thunderstorms, Wednesday morning and afternoon.

Skies will remain partly to mostly cloudy Tuesday night with areas of fog developing, some locally dense, Wednesday morning. A cold front stretching from Wisconsin to Iowa connects with an area of low pressure over the Central Plains Tuesday evening. As the front continues to move southeast into southern Wisconsin and northern Illinois, isolated showers will be possible through the Wednesday morning. 

Low pressure over the Plains will lift northeast into central Missouri and Illinois Wednesday afternoon causing rain showers to become more widespread, especially over central Illinois. There, a few thunderstorms will be possible. Rainfall amounts will range from a couple hundreths of an inch, up to a few tenths of an inch, however, heavier pockets of rain will be possible. Skies will dry out Wednesday night and for most of Thursday with temperatures holding steady in the low 70s.

Foggy Morning Commute

Good morning Stateline!  Hopefully you are having a great start to your Tuesday morning. We are off to yet another foggy start. But first, check out this image captured by our skytrack camera. Not only are you seeing the dense fog that has formed around the Javon Bae Hospital this morning, but also a glimpse of the "Strawberry" moon. June's full moon is called the "Strawberry" moon because strawberries usually ripen during the early summer time.

Clearing skies last night and light winds allowed more fog to form this morning. Only this time, it is much denser than what we experienced during the morning commute yesterday. Visibility in a few spots, like Freeport, Sterling, and Dekalb, have dropped to under 1/2 mile.

This patchy dense fog is expected to continue through the morning commute and into the mid-morning hours. Visibility during this time frame will continue to hover near a 1/4 which could cause hazardous driving conditions this morning.

As you head out onto the roads, take your time and use extra caution. It is wise to use your low-beams when encountering dense fog instead of your high-beams. The bright lights produced by your high-beams, the light would get reflected back to you.

A huge thank you to one of our First Warn Weather Watchers, Sandy Bruch from the Kirkland-Fairdale area, for sending this report in. 
Temperature - 57° 
Weather - Dense fog 
Visibility - 1/4 mile

VIEWER PHOTO: This could be the photo of the week perhaps? Another huge thank you goes to Jennelle Smith who sent in this amazing photo of the beautiful foggy sunrise from Machesney Park this morning!

Monday, June 17, 2019

Patchy Fog Returns Monday Night - Could Impact the Commute Tuesday Morning

Skies will remain partly to mostly cloudy Monday night with high pressure in control over the Great Lakes. Cloud cover has been streaming into northern Illinois as low pressure moves through the South.

A cold front draped over Minnesota and Iowa has been the focal point for thunderstorms over central Iowa, but over the past several hours those have continued to weaken. Winds will turn light Monday night and with moisture still present in the atmosphere areas of patchy fog will be likely once again Tuesday morning.

Locally dense fog will be possible but it shouldn't last too long after sunrise Tuesday morning. Skies will then turn partly to mostly cloudy for the afternoon with highs warming back near 80 degrees during the afternoon. The cold front currently located over Iowa will slide through southern Wisconsin and northern Illinois late Tuesday evening. This could bring an isolated shower to parts of the Stateline during that time, but most areas are expected to remain dry.

Friday, June 14, 2019

Father's Day Forecast

Here's a first look at your Father's Day forecast: The high temperature is forecast to be in the low to mid-70's with some very light wind. Mostly cloudy skies will be overhead the majority of the day with the chance for some scattered showers and possibly an isolated thunderstorm particularly in the morning and afternoon. However, conditions should dry out by the early evening. Tune into Eyewitness News as we will continue to update our forecasts!

Blustery Friday Afternoon

Just like yesterday's set up, a tight pressure gradient will be responsible for the windy weather this afternoon. During the afternoon yesterday, a few spots across the viewing area recorded wind gusts up near 30 mph. As we head into our Friday afternoon, two weather systems will cause even stronger wind gusts across the viewing area. Here is what we mean.
As a low pressure located over Minnesota inches closer to the strong high pressure system that is over the Tennessee Valley, the pressure gradient in between the two will straighten and tighten up resulting in some gusty winds. When it comes to Meteorology, the stronger the pressure gradient is, the strong the wind gusts will be.

And since we are smack dab right in the middle of both systems, southwesterly winds this afternoon could gust as high as 40 MPH at times. It would be a good idea to grab any loose objects in your yard or bring your trash cans inside. With winds this strong, they could end up in your neighbors yard, or even down the street. This could also make driving on east-to-west oriented roads a bit difficult for high-profile vehicles and semi-trailers.

Despite the windy conditions this afternoon, clouds will gradually increase. There is a slight chance for an isolated shower later this evening, but models still suggest much of the afternoon remains dry. After reaching our high of 74° near the start of the event, temperatures should slowly drop through the low 70s by the end. So if your Friday evening plans take you to City Market or Old Settlers Days, you’ll be good to go by leaving the umbrella at home. 

Wednesday, June 12, 2019

Rain Returns Wednesday Evening

Scattered showers will continue across northern Illinois and southern Wisconsin Wednesday evening, but with limited instability overhead the threat for thunder will remain low.  The showers are forming ahead of a cold front currently located from Janesville down to Rochelle. There are a few additional showers and isolated storms west of the front over Iowa that will move through later this evening.

Dry air moving in behind the front will help turn skies partly cloudy by Thursday morning. Winds will increase from the Northwest, gusting near 30 mph throughout the day Thursday. An isolated shower or two can't be ruled out late Thursday afternoon southeast of Rockford, but most are expected to remain dry.

Tuesday, June 11, 2019

Record Heat Builds Out West While Temperatures Tumble Further East

Record heat has been occurring up and down the West Coast the past couple of days while temperatures cool further East across the Great Lakes and Northeast.

A strong ridge of high pressure has developed along the west coast bringing triple digit heat from California to Oregon.  Heat Advisories and Excessive Heat Warnings remain in place from California to Arizona. 

The blocking pattern that has been in place will begin to break down by the end of the week and weekend with the flow of the jet stream becoming more zonal, or west to east.  This will allow fast moving storm systems to move across the middle the country with several chances for showers and thunderstorms, with the first arriving Friday night into Saturday.  Rain chances return through the weekend and into next week with possibly another round of soggy and heavy rainfall possible. 

Monday, June 10, 2019

Windy & Cooler Start

High temperatures the last 6 days here in Rockford have climbed into the low 80s.  Granted, the stretch did start with some rainfall on Tuesday and Wednesday. But after that, mother nature brought our the sun and kept thing warm and dry heading into the weekend. Unfortunately, the streak comes to an end today. A cold front has slid through Northern Illinois this morning, ushering in a slightly cooler air mass and gusty northwesterly flow.

The windy conditions starting off the new week will stick around through the rest of our Monday. Gusts through the morning and afternoon will climb to between 30 and 40 MPH at times. All of the windy weather is thanks to a cold front that passed through Northern Illinois. That same cold and a strengthening high pressure system over the Midwest is causing a tight pressure gradient at the surface. Wind gusts right now in a few spots are at or over 30 mph.

Aside of the windy conditions today, today will also feature mainly sunny skies and seasonably cool temperatures. Highs this afternoon will be in the low 70s. As that cold front continues to move farther away, winds will begin to subside, especially this evening. High pressure will slide just south of the region, which will lead mostly clear skies and light wind tonight. So if you are into stargazing, Jupiter and Saturn will be pretty close to the earth! Its going to be a beautiful night for that tonight. 

Friday, June 7, 2019

Stretch of Warm Weather Continues

After a rather cool end to May and start to June when we struggled to reach the 80 degree mark, today (Friday) marks the fourth day in a row in the 80's for Rockford.
Saturday's high temperature is forecast to be 80 degrees exactly but unfortunately that should be the end of our 80 degree streak as we expect a slight cool down to begin on Sunday and continue on through the week. Although it may not be as warm, we should have at least a few dry days in the week ahead. Tune into Eyewitness News for more!

Saturday, June 1, 2019

Severe Weather Threat for Saturday

All of northern Illinois including portions of south central and southeast Wisconsin are under a slight risk for severe weather today.
Strong to severe thunderstorms will begin to develop in southern Wisconsin by mid-afternoon and continue to form and push south until the early evening hours. The highest probability for severe storms will occur between 4PM and 6PM.
These storms should be fairly scattered meaning any given town in the Stateline Area should see a few separate rounds of heavy downpours and high winds rather than it all occurring at once. The primary threat with these storms are heavy rain and high winds although some sizable hail is very possible as well.
Stay tuned to our social media and to our newscasts as we continue to update you on these thunderstorms.