AFTERNOON – OVERNIGHT: Cool and unsettled weather continues across the forecast zones today. This thanks to the upper-level trough that remains in place across Great Lakes region.
Showers continue to develop across Indiana this morning and will continue to do so throughout the day. By 1-2 PM scattered rain and even some thunder showers will be possible across the region. Some of the rain will be mixed with or will change over to snow, sleet, and graupel.
While surface temperatures would be generally supportive of rain, aloft, temperatures are very cold. Not only does this help freeze precipitation, but it also helps create instability needed for thunder showers to develop. We measure this value using Lapse Rates; it measures how quickly temperatures cool as you rise through the environment. Generally, anything above 6-6.5 is deemed unstable, today values of 6.5-7.5 have been achieved with Lapse Rates of 9-10 possible this afternoon! So really, it’s no wonder why lightning and thunder is forecast!
Through the afternoon scattered showers will continue along with that mixed bag of precipitation. By 5-6 PM scattered showers will remain possible across the entire forecast area.
By 8-9 PM this evening an upper-level vorticity maximum will be moving through the zones. Just ahead of it another area of rain/mixed precipitation will develop and move across Indiana.
As temperatures this evening drop a transition from rain/mix to snow looks to occur from north to south as the second area of precipitation moves through. By 10-11 PM the HRRR shows this transition well.
Through the overnight that area of precipitation will work its way out of the forecast area. However, some isolated snow showers will be possible overnight. Better chances for snow look to exist in the north central portions of zone 1 along the IN/OH state line.
New rainfall totals through early Saturday morning will average from .15-.25” across zones 1 and 5. However, if you get under the heavier pockets of rain then .30-.50” isn’t out of the question locally.
While there will be some snowfall I am not expecting much in the way of accumulation. While there may be a few places that pick up a coating of snow across zone 1 in Indiana, better chances at a coating to .20” could exist across very northeastern zone 1 along the IN/OH line. Regardless, I am not expecting any major impacts from snow as accumulations would be on roofs, cars, and grassy areas.
Lows overnight will be falling into the mid 20’s to low 30’s across the forecast zones. For this reason, there are Freeze Warnings in place tonight through Saturday morning.
WEEKEND: High pressure will move in late Friday night into Saturday. This will be in control of the weather on Saturday.
While it will give us sunny to mostly sunny skies, the area of high pressure will also keep us chilly. Highs on Saturday will be in the upper 30’s north to around 50 south.
Saturday night a warm front will be moving into Illinois from the southwest. Ahead of the front isolated to widely scattered showers will develop. By 4-5 AM rain showers will become possible from south to north across zone 5 and 1 in Indiana.
Lows Saturday night into Sunday will be in the mid 20’s east to upper 30’s west. So depending on timing, some of the rain may change over to a wintry mix or snow as it moves east into eastern Indiana and western Ohio.
Through the morning hours on Sunday rain chances will increase. By 10-11 AM isolated to scattered rain will be possible across zone 5.
Through the day isolated to scattered showers will work their way from south to north. With that being said, I think there will be plenty of dry time on Sunday as well. By 2-3 PM the NAM 4 km depicts the showers in place across Indiana with the better rain chances in Illinois.
Highs on Sunday will be warmer as we get in the warm sector of a storm system. Temperatures will top out in the mid 50’s north to low 60’s south. Winds will be breezy at times with gusts of 35 mph possible.
Sunday evening into the overnight a cold front will start to work in from the north and northwest. A better chance for rain and some t’storms will move into the forecast area along and ahead of the front. By 10-11 PM the cold front will be place across northern Indiana and into Illinois.
Through the overnight the cold front and associated rain and storms will spread south across zones 1 and 5.
MONDAY: Monday’s forecast will be highly dependent on the timing, speed, and placement of the front.
It does look like the front will be slower to progress out of zone 5 on Monday. If it does remain in place rain chances would linger on Monday across southern zone 1 and zone 5.
Highs on Monday will be in the mid 50’s north to low 60’s south. However, depending on the front, temperatures could be cooler or warmer.
NEXT WEEK: Once the front and precipitation move out of the area Monday evening/night a large area of high pressure will take over our weather. This area of high pressure looks to remain in place through most of next week.
This will allow for less rain chances and more sunshine as well. Not to mention temperatures will gradually start to warm by mid to late next week to more Spring-like levels!
7 DAY FORECAST
SATURDAY: MOSTLY SUNNY, 10% CHANCE AT AN ISOLATED RAIN SHOWER. HIGHS IN THE UPPER 30’S NORTH TO LOW 50’S SOUTH. WINDS FROM THE NORTH TO NORTHWEST AT 6-12 MPH, GUSTS OF 25 MPH.
SATURDAY NIGHT: CLEAR EAST, CLOUDS INCREASING WEST, 10% CHANCE OF RAIN SHOWERS WEST/NORTHWEST. LOWS IN THE MID 20’S EAST TO LOW 40’S WEST.
SUNDAY: INCREASING CLOUDS WITH A 20-30% CHANCE OF PM RAIN, ESPECIALLY WEST. HIGHS IN THE MID 50’S NORTH TO MID 60’S SOUTH. WINDS FROM THE SOUTHWEST AT 5-15 MPH, GUSTING TO 35 MPH.
SUNDAY NIGHT: MOSTLY CLOUDY WITH A 50-60% CHANCE OF RAIN AND A T’STORM. LOWS IN THE UPPER 40’S TO UPPER 50’S.
MONDAY: MOSTLY CLOUDY WITH A 50-60% CHANCE OF RAIN AND STORMS. HIGHS IN THE MID 50’S NORTH TO MID 60’S SOUTH. WINDS FROM THE SOUTHWEST TO NORTHWEST AT 6-12 MPH, GUSTS OF 20-25 MPH.
MONDAY NIGHT: CLOUDS CLEARING WEST TO EAST, RAIN ENDS. LOWS IN THE AROUND 30 NORTH TO AROUND 40 SOUTH.
TUESDAY: SUNNY TO MOSTLY SUNNY WITH HIGHS IN THE LOW TO UPPER 50’S. WINDS FROM THE NORTH AT 5-15 MPH.
TUESDAY NIGHT: CLEAR AND COLD. LOWS IN THE UPPER 20’S NORTHEAST TO AROUND 40 WEST.
WEDNESDAY: MOSTLY SUNNY, CLOUDS LATE? HIGHS IN THE MID 40’S TO MID 50’S.
WEDNESDAY NIGHT: CLEAR TO MOSTLY CLEAR. LOWS IN THE LOW 30’S TO MID 40’S.
THURSDAY: MOSTLY SUNNY WITH HIGHS IN THE MID 50’S TO LOW 60’S.
THURSDAY NIGHT: MOSTLY CLEAR TO PARTLY CLOUDY. LOWS IN THE MID 30’S NORTH TO MID 40’S SOUTH.
FRIDAY: MOSTLY SUNNY AND WARMER. HIGHS IN THE LOW 60’S TO LOW 70’S.
FRIDAY NIGHT: CLEAR TO PARTLY CLOUDY WITH LOWS IN THE UPPER 30’S TO NEAR 50.