AFTERNOON – EVENING: A stationary front remains in place across the region today. This will be the focal point for a few afternoon rain chances. By 1-2 PM this afternoon a few rain showers will be possible across northern zone 1 in Indiana.
By 5-6 PM some more isolated to scattered rain will move in from the southwest. The latest HRRR and NAM 4km both show this batch.
Rain showers will lift northeast ahead of the main area of rain to the west through the evening. By 7-8 PM showers will be possible across northern zone 1 and entering southwestern Indiana in zone 5.
By 10 PM or so this evening rain and storms chances will increase across western and central Indiana. This as rain and storms enter into the state ahead of a forward propagating cold front.
Through the overnight rain and some thunderstorms will continue advancing east and northeast across zones 1 and 5. By 2-3 Am better rain and storm chances look to be arriving in the Cincinnati area with more scattered areas of rain/storms continuing across zones 1 and 5.
THURSDAY: By 7-8 AM Thursday morning the cold front will be entering western Indiana. Scattered areas of showers and perhaps some isolated storms will be ongoing ahead of the front across eastern Indiana through Ohio.
The front and rain will spread eastward through the morning hours. By 12 PM the front will just be moving through central Indiana and the Indianapolis area. This while most of the rain exits central Indiana. Better chances of rain will be possible across southeastern Indiana and through Ohio at noon.
Through the afternoon the front and most of the rain will work it’s way east of the forecast zones. By 5 PM the front looks to be east of Columbus, OH. While most of the rain will be out of the area, a few lingering showers will remain possible.
Highs on Thursday will be in the mid 60’s east to near 70 west. Winds will be gusty at times with wind gusts of 25-30 mph possible.
By Thursday evening a secondary cold front will be progressing eastward across Illinois. Ahead of the front some showers and storms could develop across Indiana. The latest NAM 4km model shows some isolated to widely scattered rain/storms across Indiana at 8 PM.
However, the development of these is in question, mainly because of the uncertainty that exists in the instability forecast. The NAM 4km places 1000+ J/Kg of cape from the I-70 corridor southward Thursday afternoon, if this were to verify afternoon/evening storms could redevelop. Some of which could be on the strong to even low-end severe side.
However, the NAM 12km shows about 500-750 J/Kg of CAPE Thursday afternoon. This would likely hinder any rain/storm development Thursday afternoon and would definitely shrink the strong/severe storm potential. I do currently favor the NAM 12km, it has performed better in past events than its Hi-Resolution counterpart. However, we will watch the latest trends over the next 24 hours to see if better storm/strong storm chances should be introduced to the forecast.
Through the evening into the overnight hours the cold front to the west will continue its march to the east. By 1-2 AM the cold front will be in place across Illinois and northwestern portions of zone 1. Ahead of this scattered rain and storms will be ongoing across zones 1 and 5 in Indiana/Ohio.
By 4-5 AM Friday morning better chances if rain and a few t’storms will be entering western Ohio and the Cincinnati area. Back out to the west, the cold front will be in place across central Indiana and moving through the Indianapolis area.
Lows Thursday night into Friday will be in the low to mid 50’s.
FRIDAY: By 7-8 AM Friday morning rain and storms will remain possible across Ohio while the cold front is in place across central Indiana.
Through the morning hours on Friday a wave of low pressure is forecast to move along the front per the NAM/NAM 4 km model. This would allow rain and some storm chances to persist across eastern Indiana and Ohio through mid-day.
Through the afternoon isolated to widely scattered rain and storms will remain possible across eastern Indiana and into Ohio. By 5 PM the NAM shows those areas of rain/storms.
By 9-10 PM Friday evening precipitation will exit the region giving way to what will be a nice weekend.
Highs on Friday will be in the low to upper 60’s.
New rainfall totals look to be heaviest from I-70 south. In those locations .50-1” of new rainfall looks to be widespread. However, places that get under the heavier pockets of rain or storms could see 2-2.5” in localized areas!
I will add in, a couple of models are much faster with the front and precipitation Thursday night into Friday. The GFS brings precipitation to an end early in the morning on Friday. So it’s something we will watch closely over the next 24 hours or so.
Friday night the surface high pressure will build south pushing rain and clouds to the east of the region.
Lows overnight will be chilly, falling to around 40 north to around 50 south.
WEEKEND: High pressure in place to the regions northeast will remain in control Saturday. This will give us a very nice opening to the weekend with mostly sunny skies and nice temperatures.
Highs on Saturday will be in the low 60’s east to near 70 west.
Sunday the high pressure system will move off to the southeast. As it does a warm front will be in place to the north of the region as a low pressure system gets itself together to the west.
However, a dry day is expected Sunday. With the warm front to the north and the return of the southerly flow, temperatures will once again warm.
Highs on Sunday will be in the 70’s to perhaps near 80 in some locations!
LONG-RANGE (NEXT WEEK): The pattern through next week looks to remain active as low pressure systems continue to load up and move across the United States. That isn’t to say there won’t be some dry days next week too. However, rain and t’storms will be possible as well.