EVENING – TONIGHT: A weak cold front continues across Illinois this afternoon as a strong area of low pressure moves to the forecast areas north. Right now there is not rain across the area but we are seeing some developing cumulus clouds from Madison to Vermillion Co. in Illinois. This may be the focal point for some isolated showers later this afternoon around 3-4 PM across the eastern portions of Illinois.
With the tight pressure gradients around the area of low pressure winds have really picked up with gusts of 40-50 mph being reported.
High winds will continue through the evening before slackening overnight. Winds of 40-50 mph are possible, for this reason a Wind Advisory is in place across all of zones 6 and 7 until 6 PM CST… this evening.
Overnight we will continue with partly cloudy conditions. Lows overnight will be around 40 north to around 50 south.
WEEKEND: Saturday a surface boundary will be to the north of the forecast zones. While we may start out with a few clouds I think there will be some sunshine, especially across the northern 2/3 of the forecast area. To the south more clouds will likely stick around.
Winds on Saturday will slack off with gusts if 15-20 mph possible, so not nearly as windy as what is currently occurring.
Highs on Saturday will be in the upper 50’s to upper 60’s.
While the daytime and even most of the evening hours will be dry on Saturday some rain will be approaching from the west through the evening. By 7-8 PM some isolated to scattered showers will become possible across zone 6.
By 1 AM or so better rain chances will be in place across zone 6, the better influx of rain looks to come more towards the 3-4 AM timeframe. This surge of rain may even have a couple of rumbles of thunder with it.
Lows overnight Saturday will be in the mid 30’s north, but where there is precipitation and clouds lows will likely be in the mid 40’s to low 50’s. So this will be an all rain event.
By Sunday morning around 7-8 AM there will still be scattered areas of rain across zones 6 and 7, but the heaviest of the precipitation looks to be into Indiana by this time frame.
Isolated to scattered areas of rain look to continue through mid-day, but by 1-2 PM the rain looks to be out of the forecast area. So Sunday won’t be a total washout.
The best location for heavy rainfall currently looks to be from the I-70 corridor and points just south of it. While most models suggest .50-1” of rainfall is more probable in the heaviest swaths, the NAM 4 km does show some localized areas of 1.5-2” being possible! I will add with precipitable water values of 1-1.3” it isn’t out of the question to see some of those higher amounts.
Highs on Sunday will be in the upper 40’s north to low 60’s south.
Sunday night there will be an upper level disturbance moving through, so while no serious precipitation is anticipated I will at least mention the chance for some light snow showers or flurries.
MONDAY: An area of high pressure will start to work its way into the forecast zones. This will give us dry conditions to start the week. Through the day on Monday I would anticipate a mix of clouds and sunshine.
Highs will be around 40 north to around 50 south with a light northeast wind at 6-12 mph.
MID TO LATE NEXT WEEK: We will be watching a couple of areas of low pressure develop to the regions south and west. While the majority of the models are taking these systems to the south and east of the region, we are seeing some models trend these farther west. If this were to occur then better snow chances would need to be introduced into the forecast.
Regardless, by mid to late next week a trough will move in and we will get back on the active northwesterly flow. With the northwesterly flow in place a more active pattern for clipper type snow events is likely.
7 DAY FORECAST
SATURDAY: MOSTLY SUNNY, SOME CLOUDS SOUTH. HIGHS IN THE UPPER 50’S TO UPPER 60’S. WEST TO SOUTHWEST WINDS AT 6-12 MPH, GUSTING TO 20 MPH.
SATURDAY NIGHT: INCREASING CLOUDS, 50% CHANCE OF RAIN. LOWS IN THE MID 30’S NORTH TO AROUND 50 SOUTH.
SUNDAY: PARTLY TO MOSTLY CLOUDY, RAIN ENDING FROM WEST TO EAST. HIGHS IN THE UPPER 40’S NORTH TO LOW 60’S SOUTH. SOUTHWEST TO NORTHWEST WINDS AT 5-10 MPH, GUSTING TO 20 MPH.
SUNDAY NIGHT: PARTLY CLOUDY WITH A FEW SNOW SHOWERS POSSIBLE NORTH, COLDER. LOWS IN THE UPPER 20’S NORTH TO UPPER 30’S SOUTH.
MONDAY: PARTLY TO MOSTLY CLOUDY. HIGHS AROUND 40 NORTH TO 50 SOUTH. NORTHEAST WINDS AT 6-12 MPH.
MONDAY NIGHT: MOSTLY CLEAR WITH LOWS IN THE MID 20’S TO MID 30’S.
TUESDAY: PARTLY CLOUDY WITH HIGHS IN THE UPPER 30’S AND 40’S. EAST WINDS AT 6-12 MPH, GUSTING TO 20 MPH.
TUESDAY NIGHT: MOSTLY CLOUDY, SNOW POSSIBLE? LOWS IN THE LOW 20’S NORTH TO LOW 30’S SOUTH.
WEDNESDAY: MOSTLY CLOUDY, SNOW POSSIBLE? HIGHS IN THE 30’S.
WEDNESDAY NIGHT: MOSTLY CLEAR WEST, CLOUDY WITH CHANCE OF SNOW? LOWS IN THE MID 20’S TO LOW 30’S.
THURSDAY: PARTLY TO MOSTLY CLOUDY, A FEW SNOW AND/OR RAIN SHOWERS. HIGHS IN THE UPPER 30’S NORTH TO MID 40’S SOUTH
THURSDAY NIGHT: CLOUDY WITH CHANCE OF SNOW SHOWERS. LOWS IN THE MID 20’S TO MID 30’S.
FRIDAY: PARTLY CLOUDY WITH HIGHS IN THE MID 30’S NORTH TO UPPER 40’S SOUTH.
FRIDAY NIGHT: MOSTLY SUNNY WITH HIGHS IN THE UPPER 30’S TO UPPER 40’S.