Heavy Rain and Strong Thunderstorms Possible Monday Afternoon and Evening

Heavy rain came down over southern Wisconsin and northern Illinois early Sunday morning with the Rockford Airport receiving 1.82 inches of rain! Skies have stayed cloudy through much of the afternoon and an isolated shower or two can't be ruled out through Sunday evening. More heavy rain, however, is possible Monday afternoon and evening leading to the potential risk for localized flooding.

Southwest winds Sunday night will keep temperatures on either side of 70 degrees, but also pull in quite a bit of Gulf moisture. A system moving over top a very strong ridge of high pressure centered over Texas will move into Iowa Monday morning and then into northern Illinois Monday afternoon. As it does, a warm front will begin to pull north but may fall just shy of the immediate Stateline and settle near the I-80 and I-88 corridor. South of the boundary instability (energy in the atmosphere) will build during the afternoon. This could lead to explosive thunderstorms late in the afternoon and evening. As it looks right now (Sunday evening) the greatest threat for severe thunderstorms will be outside of the area and mostly south of I-80. However, I think we'll need to keep an eye on parts of Whiteside, Ogle, Lee and DeKalb counties for the possibility for a few stronger storms.

Heavy rainfall will also be a concern with some locations receiving potentially over an inch to inch and a half of rain by Monday evening. The risk for flash flooding will likely remain where the stronger storm potential is, but a prolonged heavy rain even is possible for parts of the area which could lead to localized flooding.

Meteorologist Joey Marino and I will continue to bring you updates on the storm potential for Monday afternoon. Be sure to stay up-to-date on the latest forecast throughout the day.

Less Humid & Dry into the Weekend

A majority of the Stateline stayed dry overnight last night into this morning, but a line of heavy rain and thunderstorms did effect areas to our East including McHenry County and the Chicago metro. With that said, we missed out on yet another opportunity to receive some rainfall as the drought continues to spread across Illinois. In fact, the National Drought Mitigation Center updated the latest drought conditions map and had nearly 42-percent of Illinois under abnormally dry conditions. In comparison, roughly 18-percent was considered to be abnormally dry in last week's outlook. And it doesn't look like we could see any relief until the end of the weekend into the beginning of next week as rain chances remain low.

The better news of the day is that we did have a cold front pass through the region this morning. This front was moisture starved so we didn't see any cloud cover or precipitation with it. But, this frontal boundary has put an end to the muggy conditions we have been subjected to over the past couple of days for the time being. Winds are not too gusty this morning behind the front, but as we head into the afternoon, winds will begin to increase. Northwesterly winds could gust at times to between 20 and 25 MPH, mainly between noontime and 6 PM. So if your vehicle is particularly light-weight, you may notice a bit of a tug while traveling.

These Northwesterly winds will help squeeze in a high pressure system that is currently in the Upper Great Plains. As we head into the second half of the day tomorrow, it will be sitting just to the west in Central Iowa. This high will continue to keep things dry and bring plenty of sunshine to the Stateline. And boy will it feel nice outside today and tomorrow. Dew points look to drop down into the 50s this afternoon and stay there for our Friday. So I HIGHLY recommend taking advantage of the weather the next few days. Whether its hitting up the golf course, barbecuing, or heading out to the Boone County Fair which stretches into Sunday! 

Isolated Showers and Storms Possible Overnight

Thunderstorms, some strong to severe, have been ongoing over northern and northeast Wisconsin Wednesday evening. Those storms have been forming along a cold front, but are moving east out over Lake Michigan and will not impact any part of the Stateline this evening. A little more dry air over southern Wisconsin and northern Illinois has helped to clear our skies leaving us with a dry and clear evening.

The dry conditions won't last, however, as the cold front to the north sinks south. As it does, a few isolated showers and storms will be possible between roughly 10pm and 2am Wednesday morning. The timing of the front isn't the most favorable for thunderstorms and most of the forcing, or lift, in the atmosphere will remain to the north. However, a few of the storms may contain a brief, gusty wind and heavy rainfall. You'll notice Futurecast is keeping the entire area dry overnight.

As the front settles to the south Thursday an isolated shower or two will be possible from southern Ogle to Lee counties early afternoon, but most will remain dry. The next chance for rain won't return until late Saturday night or Sunday.

Recapping Last Night's Rain Event

If you are a late-nighter or an early riser, you may have heard a few rumbles of thunder. That's because we had line of showers and thunderstorms pushed through the region overnight ahead of an advancing cold front. Overall, rainfall totals ranged from 1.28" up in Janesville, to .72" here in Rockford, to .32" down in Rochelle. One of our first warn weather watches, Jim Bailey from Southwest Rockford, sent in a report where he recorded 1.04" in his backyard.

All we can say is, it's about time that we saw a rain event bring us a decent amount of rainfall. In fact, the last time that we got anything significant here in the Stateline was back on July 18th. The official rainfall total observed for that day was 1.66". That pretty much puts it into perspective on how dry we have been over the past couple of weeks. With high pressure in command, our rain chances have been pretty much limited. This has led to a few spots in our region to being placed under the abnormally dry category on the drought outlook. But the good news is, this recent rainfall should bring back some color to your lawn!

Today marks the 91st day that the Rockford International Airport has received 0.01" of rainfall or greater since the beginning of the year. That contains about 42% of the year and places 2019 tied for second place on record for most days with measurable precipitation!

Quiet Start to the Work Week, Storms Possible Later

Even if you have those Monday feels, we are starting off the work week with plenty of sunshine once again. High pressure centered to the southwest of the region has brought a quiet start to our Monday. The good news is, this high pressure system will continue to influence our region and keep most of our Monday dry. Partly sunny conditions and winds out of the southwest should help temperatures climb into the upper 80s. As warm moist air gets streamed into the region, dew points will hold steady into the upper 60s. So it is definitely going to feel a bit muggy out there.

As we work our way towards the end of the evening commute, a cold front which is currently draped across the northern Great Plains, will slowly sag to the south bringing with it a chance for thunderstorms. Some of which could be strong to severe. As of the 8 AM update from the Storm Prediction Center, the Enhanced Risk (3 out of 5) has been expanded farther eastward and now includes extreme northwest Jo-Daviess county. This leaves a majority of the Stateline under a Slight Risk (2 out of 5).

Models are in agreement that these thunderstorms will be most likely move into the region between 7 p.m. and 10 p.m. Typically with a line of thunderstorms, the biggest concerns will be gusty winds and also heavy rainfall. During the early morning hours of our Tuesday morning is when we should see conditions begin to wind down. chances for Tuesday are still present. Isolated thunderstorms are possible tomorrow, but coverage doesn’t look as substantial as what it will look like later this evening.A second cold front is set to pass through Wednesday night into Thursday morning and will bring much cooler temperatures to the region for the second half of the week!

Warm Start To The Week . . . Then Cooler

August is off to a warm start with all 4 days above the average high temperature of 84 degrees (for the first 3 days) and 83 degrees today (we hit 91!).  August is continuing where July left off.  July was the first month this year in which our average monthly temperature was above average (3.7 degrees above). We had 12 days last month at or above 90 degrees and we've added one in August now. 

Our temperatures will continue above average thru Wednesday before they start to fall below the average high - subsequent to the passage of a strong cool front from the Northwest. It looks like temperatures will continue to trend on the cool side as the Climate Predication Center has released its forecast for August, and the forecast shows a 40% chance that temperatures will be below average.  In addition to the forecast, our average temperatures peaked and now are starting to fall - so lets appreciate the remaining warm days we have this month!  

July Climate Summary

Here's our July in a nutshell:

Our average high temperature for the month of July was over 3 degrees higher than normal. We exceed the normal for average low temperature by over 4 degrees. In fact, we tied the all time record for the warmest low temperature at 80 degrees on the 19th. Plus, the lowest temperature for the entire month occurred on the morning of the 31st, the last day of the month, when we fell to 57 degrees. We more than doubled the average number of days exceeding 90 degrees at 12; our normal for the entire year is 14.9 days. Unfortunately, we fell 1.15 inches short of our normal rainfall for the month, a sizable deficit. However, the month of August is forecast to bring above average precipitation while temperatures float around normal.