Isolated risk for damaging winds, heavy rainfall

Cloud cover, less wind, and scattered rain showers and thunderstorms held temperatures in the upper 80s Tuesday afternoon. This was the break that we and our air conditioning units needed after Rockford saw 3 straight days with highs in the 90s.

 
 

 

Fortunately, more of the same can be expected for our Wednesday as the ridge responsible for the recent heat continues to break down to our east. Wednesday begins in the 70s, which will be a warm enough start to allow temperatures to climb into the upper 80s. A warm front lifting in from the south will help pop a few thunderstorms late this afternoon. Some of which could be on the strong to severe side. 

  

Like Tuesday, the Storm Prediction Center has the entire Stateline under a level 1 of 5 Marginal Risk for severe weather, mainly for strong winds up to 60 mph. Heavy downpours will also be a concern as the atmosphere remains juiced up with moisture. Isolated chances remain overnight with temperatures falling into the low 70s before sunrise. 

 

Tomorrow also features a Marginal Risk for severe weather, mainly for strong winds. However, we do see an uptick in heat and humidity which will place afternoon highs in the low 90s and heat index values close to the triple digit mark. While not as dangerous as the heat from earlier in the week, I would still make sure heat safety is being implemented. Again, that's making sure to wear light colored clothing, take frequent breaks in the shade and air conditioning, and of course remain hydrated.

Scattered shower and storm chances continue this week

 It was another humid day Tuesday with scattered showers and storms on and off throughout the day. We will remain mostly dry through much of the night before additional showers arrive toward the early morning hours of Wednesday. If there is any thunder in these showers, it would be very isolated.

Much of the daytime of Wednesday may appear very similar to Tuesday. Spotty showers on and off through the afternoon, with only about 20-30% coverage over the region. Highest coverage of showers and storms will be focused to the North along a frontal boundary.

Much of the daytime Thursday could be dry for most in the Stateline, with rain coverage even lower than Wednesday afternoon. But toward the evening, the frontal boundary will slide back South as a cold front, bringing a higher coverage of rain and storm chances along it.

This graph shows the rainfall coverage over the next four days, with the highest coverage arriving Thursday evening into Friday along and just behind that aforementioned cold front. Outside of that, the highest coverage will likely remain near 20-40% through Saturday.

As for our severe weather chances, most storms will remain sub-severe. But Wednesday and Thursday feature an isolated risk for a strong to severe storm, with a Marginal (Level 1/5) risk from the Storm Prediction Center in place.

Temperatures ease a bit as on and off storms chances push through

Summer has been "summering" big-time as Rockford has observed three 90° days since we made the swap from spring to summer last Friday. 

Looking ahead, afternoon highs look to remain above average, hovering around the 90° mark. However, tagging along with this consistent summer-like heat will be a daily chance for storms. 

Beginning with today, a weak disturbance sliding in from the west will help provide enough of a push for scattered storms this afternoon. One or two of these storms could be strong to severe. For that, the Storm Prediction Center has left the entire Stateline area under a level 1 of 5 Marginal Risk, mainly for strong winds. With our atmosphere juiced up with moisture, heavy rain will also be a concern. Something to keep an eye on for Food Truck Tuesday! 

This scattered threat will carry on into the overnight hours, with temperatures falling into the upper 60s. Tomorrow, same ordeal. This time, storms that pop up during the afternoon will be associated with a warm front lifting in from the south. Similar to today, the Storm Prediction Center has the entire area under a level 1 Marginal Risk. Again, strong winds and heavy rain will be the primary concerns.

Thunderstorm chances continue into Thursday and for the 3rd day in a row, the Storm Prediction Center has the region under a Marginal Risk. By the weekend, our chance for rain and storms will lessen, though our temperatures will increase. Expect afternoon highs to be at or above 90° before falling back into the mid to upper 80s early next week.

Heat advisory continues, storm chances return this evening

It will be another warm night as overnight lows have fallen back into the mid 70s. As we've seen the past few days, these warmer morning have paved the way for dangerous hot afternoons. 

Same story today. In fact, today will be slightly hotter and could become the warmest day of the year. Highs are slated to reach the mid-90s, which will place heat indices near or just above 100°. Humidity may drop a little bit with drier air mixing down from above, but that will make for any relief. 

Some relief arrives this evening in the form of a batch of scattered storms to the northwest. Now, storm coverage does decrease the further south and east you go, and some spots southeast of Rockford may stay totally dry. That said, any storms that develop will be capable of producing damaging wind gusts and heavy rainfall. Much of the Stateline is under a Level 1/5 Risk from the Storm Prediction Center.

 

We won't see an extension of the heat advisory that is currently in place for the Stateline. The heat index is only expected to sit in the 90-95 range Tuesday, then back into the 85-90 range Wednesday. 

Afternoon highs will sit rather close to the 90° mark during this two stretch, eventually peaking in the low 90s Thursday afternoon.
 

Slight improvement in humidity with increased storm chances this week

 We have been remarkably warm the last few nights, setting record "warm" lows both yesterday and today. Today's record warm low also ties the all-time record warm low for the month of June!

It will be another warm one tonight, with overnight lows again in the mid-70s. Tomorrow afternoon will see highs in the mid-90s again, placing heat index near 100° at times through the middle part of the day. Humidity may drop a little bit with drier air mixing down from above, but that will not any noticeable relief to the humid feel.

Some relief arrives late in the evening in the form of scattered storms to the Northwest. Confidence in storm coverage decreases the further South and East you go, and some spots Southeast of Rockford may stay totally dry. That said, any storms that develop will be capable of producing damaging wind gusts and heavy rainfall. Much of the Stateline is under a Level 1/5 Risk from the Storm Prediction Center.

 

Scattered showers may linger into Tuesday morning, with another wave of storms arriving toward the evening. This will bring a better chance for rain across all of the area, but a slightly lower threat for strong to severe storms. Similar to Monday evening, the strongest storms will be capable of heavy rain and damaging winds. Another Level 1/5 Marginal Risk is in place from the SPC.

 

It will remain humid through much of the week, but not quite to the level of heat advisory criteria (heat index of 105° or higher). Temperatures will hover between the upper 80s to around 90° Tuesday through next weekend, with dew points near 70°. This also comes with more frequent rain and storm chances, particularly between Wednesday and Thursday.

Hot and humid weather continues into next week

 It sure was a hot one in the Stateline today, as Rockford's temperature reached 93° Saturday afternoon, with a peak heat index of 105°! We will see little relief from the heat, with heat indices remaining in the 80s for much of the night. Overnight low temperature may only drop to the mid-70s, which would set a new record warm low for today's date in Rockford.

The extremely mild start will kick off another hot day tomorrow. For those participating in or watching the Ironman race tomorrow, be sure to stay hydrated! It will be a hot one from start to finish, with the heat index reaching the 90s by mid-morning. It'll be another breezy day too, with SW winds around 15-25 mph.

It will remain hot and humid both Sunday and Monday with high temperatures well into the mid-90s. Overnights will once again provide little relief from humidity, with low temperatures still in the 70s. Peak heat indices will reach near or above the triple digits, very similar to Saturday.

A heat advisory will remain in effect until Monday night across the entire Stateline. There is a chance this may need extended later into the week if confidence increases on higher humidity into Tuesday or Wednesday. At this time, our forecast high will be in the upper 80s to low 90s through the end of next week.

We will see subtle relief from the humidity with increasing chances for storms, beginning Monday evening. Storm chances will begin from the Northwest Monday afternoon and slowly work our direction into the evening and night. There is a slim chance a few of these storms may produce gusty winds and large hail near severe limits. The Storm Prediction Center has placed much of the area under a Level 1/5 Marginal risk for severe weather Monday evening.

Heat advisories in effect this morning; first summer heat wave through the weekend

 Our first summertime heat wave will be making headlines this weekend as a ridge of high pressure has moved in allowing for very warm temperatures and high dewpoint temperatures to stick around staying undisturbed which will shoot our heat index up to 105° for multiple days!

Temperatures to start the morning are already warm, along with a muggy/humid feel outside as well. We're already up 10° in some spots compared to yesterday morning which looks to be a similar trend with our high temperatures into the afternoon and evening. Right now, heat indices are not that high, however as temperatures warm along with higher dewpoints moving in, we'll see that chance quickly.

Due to heat indices expected to reach near 105, heat advisories have been issued for the entire state line along with a majority of the Midwest and Northern Plains. These heat advisories will last until Monday night as temperatures will be in the upper 90's, although will fall just slightly short of our record highs for the upcoming days.

Expect heat indices to peak during the afternoon times the next few days, as most often when we reach our highest surface temperature will be during the afternoon hours. Saturday will contain a bit more moisture in the atmosphere helping bump heat indices near 105-110° at times however Sunday and Monday, mixing in our atmosphere will decrease dewpoint temperatures slightly giving us very little relief.

This will be our first exposure to dangerous heat this summer so it will be crucial to practice heat safety this weekend as most of us aren't accustomed to this type of heat yet. Keep an eye on your loved ones, pets, and most importantly yourself through the weekend making sure you stay hydrated, take frequent breaks inside, and wearing light colored clothing. Especially for those going out to watch the Ironman event tomorrow, coolers filled with water and shade providing equipment will be necessary!