AFTERNOON-OVERNIGHT: Mostly sunny to partly sunny skies continue across zones 1 and 5 this morning. However, across southern Indiana clouds are starting to thicken up ahead of some approaching rainfall.
Energy from the incoming 500 mb trough still located in the desert southwest and the positively tilted upper-level trough across the Great Lakes will supply the energy needed to bring in rain chances over the next 36-48 hours. Rain is currently trying to move into Illinois, but thanks to dry air, it is quickly evaporating.
Through the afternoon the environment will begin to become more saturated, eventually reaching the point rain can be supported and reach the ground. While a couple stray showers could impact southwestern Indiana through the afternoon, the better chance of rain will enter southwestern Indiana around 5-6 PM.
This will be with the arrival with a small 500 mb disturbance that will roll across the forecast area.
Rain will continue to work into the forecast zones from southwest to northeast through the evening into the overnight. By 1-2 AM Tuesday morning rain looks to be moving into Cincinnati and Indianapolis.
Through the overnight rain will continue to spread in across zones 1/5 in both Indiana and Ohio. The heaviest rain will be located from the I-70 area southward, with possibly a couple rumbles of thunder mixed in there.
Lows overnight will be in the mid 40’s north to around 50 south.
TUESDAY: By 8-9 AM Tuesday morning areas of rain will be ongoing, especially across southern/eastern Indiana and into Ohio. Some of which will be moderate to heavy at times.
Through the morning an area of high pressure will be starting to move south across northern IL/IN/OH. This will create a bit of a wind shift/surface boundary. This will not only push better rainfall chances south of I-70, but the drier air working in should allow the coverage to become less. By 12-1 PM the NAM 4 km shows the lower coverage across the zone forecast area.
Through the afternoon rain to the south will continue to move east and get pushed south as the high moves in. This will allow rain chances to decrease across southern zone 1 and zone 5. However, farther to the north where the wind shift/surface boundary is in place, some scattered afternoon rain or even an isolated storm could develop. By 5-6 PM scattered areas of rain will be ongoing.
Highs on Tuesday will be in the low 50’s to around 60.
Through the evening Tuesday into the overnight the area of high pressure will move into the forecast area. This will allow rain to come to an end across the region through the overnight. It looks like by 1-2 AM Wednesday only a few isolated showers will be ongoing, but these will fade out through the overnight.
New rainfall totals look the most impressive from I-70 south across Indiana where .60-1.10” will be common. However, across zone 6 new rainfall totals of 1.75-2.75” are not out of the question where the heaviest embedded rainfall banding sets up.
Farther east across Ohio the heaviest rain still looks to be placed from I-70 south. This is where .40-.60” will be possible.
Lows Tuesday night into Wednesday will be in the low to mid 40’s.
WEDNESDAY: High pressure to the west will be in control of the weather on Wednesday. This will allow dry air to move into place across zones 1 and 5. So sunny to mostly sunny skies are expected.
There will be a slight upper-level disturbance on Wednesday. While it will not be enough to generate rainfall, it will likely prove enough to generate at least some scattered clouds across northern zone 1 through the afternoon.
Highs on Wednesday will be in the upper 50s north to mid 60’s south.
THURSDAY-FRIDAY: The area of high pressure will start to move off the east. However, it will still have the largest impact on the weather across the forecast region on Thursday.
While an area of low pressure will be moving closer to the region from the southwest on Thursday, the area of high pressure will slow it down some. This will allow conditions to remain dry with mostly to partly sunny skies.
Highs on Thursday will be warmer with temperatures topping out in the mid 60’s to low 70’s.
Thursday night the area of high pressure will move out of the forecast area and the area of low pressure will start to move in. As the low moves in, rain chances will be on the increase through the overnight into Friday.
Through the day on Friday the area of low pressure looks to move right along the Ohio River, this track would bring in more chances of rain and possibly some t’storms through the day on Friday.
WEEKEND: The weekend does look unsettled and cool. This will be thanks to an upper-level low that gets cut-off temporarily from the main flow. This will spin across the region both Saturday and Sunday.
With that in place, at least isolated to scattered rain chances will be possible both days. While models are not totally in agreement with timing/location of the low and precipitation chances, we will be watching for trends and fine-tuning the forecast as we get closer to the forecast period.
7 DAY FORECAST (Temperatures will vary generally cooler north to warmer south)