AFTERNOON – OVERNIGHT: Mostly to partly cloudy skies remain in place across zones 1 and 5 at mid-day with some ongoing showers as well. However, there is some clearing working into Indiana.
Through the afternoon the HRRR is pretty aggressive with clearing across Indiana. While I am always pessimistic about any major clearing with an upper-level trough in place, some sunshine looks to get through this afternoon at least across portions of Indiana.
That upper-level trough continues to spin across the forecast region today. This is what is responsible for the nasty, damp weather . Through the afternoon rain showers will be possible across both zones 1 and 5 in Indiana/Ohio. By 2-3 PM scattered showers can be seen ongoing via the HRRR model.
Through the afternoon and into the evening showers will remain possible. By 7-8 PM scattered showers will still be ongoing across the forecast area.
This afternoon/evening very cold air will be present aloft. This will allow instability/steep lapse rates to occur. With this in mind some small hail cannot be ruled out in some of the heavier cells today.
This evening as the sun sets and we lose daytime heating, rain shower chances will decrease. However, with the pesky upper-level disturbance still in place at least isolated shower chances will remain through the overnight.
Through the overnight we will be watching a cold front with rain and a few storms move closer to the forecast area. By 5-6 AM rain with perhaps a couple t’storms will be entering very northwestern portions of zone 1.
Lows overnight into Wednesday will be in the mid 40’s northeast to near 50 south.
WEDNESDAY: The rain and some isolated t’storms will move southeast across Indiana early in the morning on Wednesday. By 7-8 AM the line of precipitation will be moving southeast and entering the Indianapolis metro area. With some instability in place as the rain moves through, some rumbles of thunder will be possible.
By 12-1 PM Wednesday, rain will be moving across eastern Indiana and entering western Ohio. At this time, it would be impacting the Cincinnati area. However, the cold front will be lagging behind somewhat, as it will just be moving through the Indianapolis area around noon.
Through the afternoon the front and associated precipitation will move off to the east and southeast. By 4-5 PM the cold front will be across western Ohio and across the Cincinnati vicinity. Rain and some t’storms will be possible along the front.
Rain chances will decrease behind the cold front Wednesday. However, with the main upper-level low sitting right over the top of the region I still think isolated showers will remain possible.
With very cold air aloft tomorrow some hail could occur within some of the rain and storms. There also could be some cold air funnels under the upper-level low.
Through the evening into the overnight isolated rain showers will remain possible.
Highs on Wednesday will be cool with temperatures topping out in the mid 50’s north to low 60’s south. Winds will be strong at times with 30-40 mph wind gusts from the north possible.
Wednesday night the upper-level low will move out of the forecast area and an area of high pressure will begin to build in behind it. While this will be occurring, there may be enough of a disturbance left to create some isolated rain showers, so I will leave those chances in there through the overnight.
Lows Wednesday night into Thursday will be in the upper 30’s north to mid 50’s far south.
THURSDAY: We may start out with a few clouds and showers Thursday depending on exactly how quick the upper-level low exits the region. The NAM does show some of these very isolated to light showers in place around 7-8 AM.
However, as the area of high pressure works in at the surface drier air will filter into the region. This will allow for all the precipitation to end and clouds to erode through the morning hours.
New rainfall totals of .20-.40” look to fall on average through Thursday morning. However, heavier totals of .75-1.10” will be possible under some of the heavier pockets of rain and/or thunderstorms.
By the afternoon Thursday the sun will be out and things will start to dry out.
Highs on Thursday will be warmer with the drier air and sunshine in place. Temperatures on Thursday will rebound into the low to mid 60’s in most locations. Places farther east temperatures may be cooler as clouds will hang on a bit longer there. Winds will be breezy at times on Thursday with gusts of 20-30 mph possible at times.
FRIDAY: At the surface the area of high pressure will continue on Friday. This will allow sunny and dry conditions to remain to end the week.
At the upper-level a ridge of high pressure will be building in. Not only will this reinforce the dry air, but it will also allow warmer air to expand northward, so temperatures are expected to further increase by the end of the workweek.
Highs on Friday will be in the 70’s.
WEEKEND: The upper-level ridge looks to break down through the day on Saturday. This would allow a cold front to swing through Saturday afternoon into the evening hours. Along the front rain and t’storms will move quickly southward through afternoon and evening.
Highs on Saturday will be in the mid 70’s to low 80’s across the area. Of course temperatures will be dependent on timing of the front and the amount of sunshine that is realized.
While the atmosphere doesn’t look overly impressive Saturday, some moderate instability coupled with some “stronger” winds aloft may allow some strong to severe storms develop. However, details are very fuzzy right now and that’s a threat we will have to fine-tune through the week if needed.
Sunday model guidance is suggestive that the front stalls out across southern portions of the zone Saturday into Sunday. This would allow for rain to continue overnight Saturday into Sunday.
However, models are not in agreement with the timing and placement of an area of high pressure on Sunday. While the GFS and CMC bring it in directly over the region, the EURO keeps it farther north.
Just going off of the current pattern, I would think the front will indeed stall in southern zones Sat night into Sunday. The high will build in across northern Indiana/Illinois Sunday. Isolated to scattered rain/storm chances will be possible across southern portions of the zone forecast area on Sunday. Overall, we will have to see how things play out and we will fine-tune the forecast as we get closer to the weekend.