AFTERNOON – OVERNIGHT: A mix of clouds and sun continues across zones 1 and 5 late this morning. While some locations did start off the day with some fog and mist, that has since eroded.
Through the afternoon we will see more cloud cover move into the forecast area ahead of the next storm system. While most of the daytime hours will be dry today, some rain will start to enter southwestern Indiana across zone 5 by 4-5 PM this evening.
By 8-9 PM rain will be moving to the north across zone 1 and 5. Some rain showers may enter the Cincinnati area around 9 PM or so this evening.
Through the evening into the overnight rain showers will continue lifting northward across southern Indiana. By 12-1 AM areas of rain look to be in place just south of I-70 across southern zone 1 and zone 5.
Through the overnight rain will slowly progress to the north. While the NAM does hold precipitation off in the metro until 6-7 AM, I think showers will be possible across the I-70 area by 3-4 AM.
Lows overnight will be in the mid 40’s northeast to upper 50’s south.
SATURDAY: Rain and some t’storms will be continuing to lift northward across Indiana and southwestern Ohio by 8-9 AM Saturday morning. This will be ahead of a northward lifting warm front.
By 12 PM the better concentration of rain looks to be in place across northern/eastern Indiana and into western Ohio. Across southern/southeastern Indiana more isolated to scattered rain/storms look to remain.
Through the afternoon an area of low pressure will be moving in from the west. Ahead of the low pressure system a warm front will be lifting across southern and western Indiana. As the front lifts into the region from the south, it should allow precipitation to become more isolated to scattered through the afternoon. By 5 PM only scattered rain and storms will be in place.
Highs on Saturday will depend largely on the placement of the warm front. North of the front highs will only be in the mid 50’s to low 60’s. However, south of the front highs will be in the mid 60’s to low/mid70’s.
Through the afternoon some instability will build eastward into the western/southern portions of Indiana. Right now models show 500-1000 J/Kg of CAPE possible through late afternoon and early evening.
With the warm front in place along with some pretty strong low-level winds at 45-55 knots, it is possible some strong to even severe storms could develop across western zone 1 and western zone 5 in Indiana. The main timing for these would be late afternoon into the early evening before better dynamics exit out of the area.
Main risks with any severe storms would be damaging winds and hail. However, a couple of isolated tornadoes can’t be ruled out.
By 7-8 PM the warm front will be in place across western/southwestern Indiana. Scattered t’storms may develop along this front by this time. Again, some could be on the strong to severe side too.
Through the evening the initial storms will move off to the east. By 10-11 PM only isolated to widely scattered showers will be in place across Indiana with a better chance for some thunderstorms across Ohio.
Through the overnight the low pressure system and cold front to the west will move into Indiana. Rain and t’storms will be ongoing along the front. By 4-5 AM Sunday morning rain and storms will be entering Indiana, it is possible a couple of these storms could still be on the strong side.
SUNDAY: Through the morning hours on Sunday the area of low pressure and cold front will be pushing eastward across Indiana. Ahead of it rain and storms will still be ongoing. However, any surviving storms will be losing their steam by this time.
Highs on Sunday will be in the low 60’s north to mid 70’s far south.
Through the afternoon the low pressure system and cold front will continue to advance off to the east. However, some decent instability is forecast to develop across southeastern Indiana and southwestern Ohio Sunday afternoon. The 12z NAM shows 2000-2500+ J/KG of CAPE in the area Sunday afternoon/evening.
While winds at 850 mb will be pretty weak, 500 mb winds will be very impressive with 50-60 mph westerly winds aloft. The models also depict a 500 mb vorticity max moving through the area at that time. However, I will say the two features are displaced, but I won’t be shocked if later model runs do synch those up.
While there are a lot of details that need worked out regarding strong to severe storms potential Sunday afternoon, based off the current data it at least deserves a mention. Best chances for strong to severe storms would be in southeastern Indiana and southwestern Ohio.
By 7-8 PM Sunday evening the NAM 4km model does show rain and some more storms forming across zones 1 and 5 in association with the upper level vorticity maximum.
Through the overnight Sunday into Monday rain and storms will exit to the east and a mostly dry overnight is expected.
New rainfall totals through the end of the weekend look to average around .75-1.15” across the forecast area. However, places that do get under the more concentrated areas of rain or a strong/severe thunderstorm could see 1.5-2” or so of new rainfall.
MONDAY- TUESDAY: A large are of high pressure will build into the central U.S. to start next week. This will ridge into the region allowing for mostly dry conditions Monday into Tuesday.
However, by Tuesday we will return to a more northwesterly flow aloft. While no significant systems usually occur in the flow (in the warm months), a piece of energy looks to break off on Tuesday and move through the region.
Although high pressure will remain in place some rain looks possible Tuesday afternoon.
Highs to start next week will be cooler, with temperatures topping out in the 60’s to perhaps around 70 south.
LONG-RANGE: With an upper-level ridge building to the west, an upper-level trough and northwesterly flow looks to remain in control of the weather across the forecast zones through next week.
As some energy moves through the 500 mb flow there will be chances of rain showers next week. Although, I’m not expecting any major rain events.
With the rough building in it will keep temperatures below average for most of next week.