AFTERNOON – OVERNIGHT: Rain and t’storms continue to develop across zones 6 and 7 this morning. This is thanks to an area of low pressure and associated cold front that will be moving across the forecast area today.
While rain and some t’storms will continue through the morning hours across zones 6 and 7 the cold front will sweep to the east taking the precipitation with it. By 12-1 PM today the cold front will be in place across the IN/IL state line, with a large majority of the rain in Indiana.
While the main area of rain will be to the east there will still be a few rain showers around, mainly to the north. Once the front is through, dry air will work in so rain chances look pretty small after early afternoon. The dry air will also help erode some of the clouds too. While I still think there will be lots of cloud cover, some sunshine should peek through.
Temperatures through the afternoon will be cooling behind the cold front. We are in the upper 50’s to mid 60’s at 6 am. However, by 6 PM temperatures will be in the low 40’s to mid 50’s across Illinois.
Winds through the day will remain strong with gusts of 30-40 mph possible.
With areas of heavy rain and t’storms some impressive rainfall totals looks possible in places. The latest Hi-Res data from the RAP and HRRR suggest a pretty large area of .50-.90” of rain with localized places getting 1-1.5” of rainfall under the heaviest pockets!
Overnight colder air will continue to surge in behind the cold front. As it does any small amounts of leftover moisture will changeover to some light snow showers or flurries. These look pretty isolated overnight with no accumulation expected.
Lows will be in the low to upper 30’s.
FRIDAY: Through the morning hours Friday a 1020 mb area of high pressure will build in across the forecast zones. This will allow for dry air to really work into the forecast area resulting in sunny to mostly sunny skies.
Temperatures on Friday will be on the cool side as the high pressure allows that cold air to remain in place, at least briefly, to end the workweek. Highs on Friday will be in the mid 40’s north to mid 50’s south. Winds will also be much calmer with northwesterly winds at 6-12 mph.
Friday night the area of high pressure will start to move off to the northeast. However, it will still be in control of the weather.
Lows overnight Friday into Saturday will be in the low 30’s north to around 40 south.
WEEKEND: Saturday we will be in between two weather systems. This as the area of high pressure continues to the east and an area of low pressure develops across the Great Plains.
Regardless, this will result in a very pleasant start to the weekend as sunny to mostly sunny skies will be in place. Afternoon highs on Saturday will be in the upper 50’s north to upper 60’s south, and with light southeast wind at 5-15 mph it will be a beautiful spring day!
Overnight Saturday night into Sunday skies will be mostly clear to partly cloudy. Lows will fall into the upper 30’s to upper 40’s.
Sunday an area of low pressure will move closer to the forecast area from the southwest. As it does a warm front will start to lift through the forecast area on Sunday. This will allow a very warm, moist southerly flow to return to the forecast area Sunday afternoon.
Highs will top out in the upper 50’s north to near 70 south. Obviously the high temperatures will be highly dependent on the timing and location of that warm front Sunday, so it’s something we will have to fine tune for you.
Through the day Sunday there will be a mix of sun & clouds. Right now models are still a little fuzzy on the timing and placement of the system Sunday afternoon/evening.
However, better chances of rain and t’storms look to occur late in the evening into the overnight per the latest EURO model. While the 6z NAM forecast only extends out to 1 PM Sunday, it does seem to be in agreement with the EURO on precipitation placement at that time.
Depending on the exact track and placement of the low pressure system, fronts, and upper level features strong to strong storms could be a possibility Sunday evening into the overnight. Right now the details are pretty blurry and will definitely need fine-tuned.
Lows Sunday night will be in the mid 30’s to mid 40’s behind the system.
MONDAY: The area of low pressure will move off to the east of the region. While some isolated to scattered areas of rain could remain in place through the morning hours, rain chances will come to an end from west to east through the day.
Highs on Monday will be in the mid 40’s to upper 50’s.
NEXT WEEK: An area of high pressure will build in behind the system late Monday and Tuesday. This will allow the weather mid-week to remain quiet with perhaps a few rain chances possible Wednesday.
Temperatures next week will moderate once again with highs in the upper 50’s and 60’s mid-week.
7 DAY FORECAST
FRIDAY: DECREASING CLOUDS, COOLER. HIGHS IN THE MID 40’S NORTH TO MID 50’S SOUTH. WINDS FROM THE NORTHWEST AT 6-12 MPH.
FRIDAY NIGHT: CLEAR TO MOSTLY CLEAR WITH LOWS IN THE LOW 30’S NORTH TO AROUND 40 SOUTH.
SATURDAY: SUNNY TO MOSTLY SUNNY. HIGHS IN THE UPPER 50’S NORTH TO UPPER 60’S SOUTH. WINDS FROM THE SOUTHEAST AT 5-15 MPH.
SATURDAY NIGHT: MOSTLY CLEAR TO PARTLY CLOUDY. LOWS IN THE UPPER 30’S NORTH TO UPPER 40’S SOUTH.
SUNDAY: INCREASING CLOUDS WITH A 30% CHANCE OF RAIN & T’STORMS WEST. HIGHS IN THE UPPER 50’S TO UPPER 60’S. WINDS FROM THE SOUTHEAST AT 6-12 MPH, GUSTING TO 20 MPH.
SUNDAY NIGHT: MOSTLY CLOUDY WITH A 40-50% CHANCE OF RAIN & T’STORMS. LOWS IN THE MID 30’S NORTH TO MID 40’S SOUTH.
MONDAY: PARTLY TO MOSTLY CLOUDY WITH A 30-40% CHANCE OF AM RAIN SHOWERS.HIGHS IN THE MID 40’S TO UPPER 50’S. SOUTHWEST TO NORTHWEST WINDS AT 10-20 MPH, GUSTING TO 40 MPH.
MONDAY NIGHT: DECREASING CLOUDS WITH LOWS IN THE MID 30’S NORTH TO AROUND 40 SOUTH.
TUESDAY: SUNNY TO MOSTLY SUNNY WITH HIGHS IN THE LOW 50’S TO LOW 60’S
TUESDAY NIGHT: PARTLY CLOUDY WITH 20% CHANCE OF SHOWERS WEST. LOWS IN THE UPPER 30’S TO MID 40’S.
WEDNESDAY: MIX OF SUN & CLOUDS WITH A 20% CHANCE OF RAIN. HIGHS IN THE UPPER 50’S TO MID 60’S.
WEDNESDAY NIGHT: INCREASING CLOUDS, CHANCE OF RAIN. LOWS IN MID 40’S TO MID 50’S.
THURSDAY: PARTLY CLOUDY 20-30% CHANCE OF RAIN & T’STORMS. HIGHS IN THE MID 60’S TO LOW 70’S.
THURSDAY NIGHT: MOSTLY CLOUDY WITH A 30-40% CHANCE OF RAIN & STORMS. LOWS IN THE MID 40’S TO MID 50’S.