An unusually strong upper level low pressure system and surface cold front moved through central Indiana during the late morning and afternoon hours of June 10th. A very humid air mass was in place behind a tropical system that had passed through.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS IND wrote it up.
An unusually strong upper level low pressure system and surface cold front moved through central Indiana during the late morning and afternoon hours of June 10th. A very humid air mass was in place behind a tropical system that had passed through. This combined with the strong dynamics allowed for storms with very strong wind gusts and some large hail to form. The strongest storms were north and east of the forecast area. Numerous reports of winds up to 70 mph and hail as large as an inch occurred with this storm system. The most severe damage occurred in portions of Tipton and Howard counties.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Indianapolis, IN wrote its last area forecast discussion before the first event at Jun 10, 11:20 AM EST, 47 minutes earlier.
Area Forecast Discussion National Weather Service Indianapolis IN 1220 PM EDT Wed Jun 10 2020 .UPDATE... The AVIATION Section has been updated below. && .SYNOPSIS... Issued at 342 AM EDT Wed Jun 10 2020 A strong upper level low with an associated surface wave and cold front will sweep across the region later today...bringing the chance for showers and thunderstorms and a potential for severe weather across eastern Indiana. High pressure will then build in tonight with dry and seasonable weather through the end of the week. A cold front will track through the area Friday night with pleasant temperatures and mainly clear skies for the weekend. Progressively warmer temperatures return next week. && .NEAR TERM /Today/... Issued at 1007 AM EDT Wed Jun 10 2020 Bumped up the timing of precip across the east by a couple hours, otherwise forecast looks good. Previous discussion follows... Central Indiana in a bit of a lull early this morning as the remnants of Cristobal shift away to the north. The remnant low currently resides over northern Wisconsin and continues to move N/NE. A secondary upper low pivoting through the central Plains is assisting in pockets of convection across the Missouri bootheel with both circulations contributing to a band of storms from eastern Iowa to southwest Michigan. A tropical airmass lingers across the forecast area this morning...with 07Z temperatures ranging from the mid 70s to lower 80s. After the swing and a miss with respect to severe weather over central Indiana on Tuesday...prospects appear much more favorable for more widespread impacts from robust convection later today as the secondary upper low over the central Plains tracks east into the area and gradually takes on a favorable negative tilt. The impressive dynamics aloft and the presence of the frontal boundary will provide the atmospheric trigger to jumpstart convection that was lacking over central Indiana on Tuesday. The overall trend in the model suite over the last few runs has continued to slow the eastward progression of the approach of both the upper low and the associated surface low and cold front. Good agreement exists on the front sweeping across the forecast area from west to east late morning through mid/late afternoon. The airmass over the region ahead of the front will remain oppressive with dewpoints in the low to mid 70s common. Considering our warm start this morning and likelihood at favorable heating with sunshine increasing as the morning progresses...should not have a difficult time getting modestly unstable. To that argument...CAMs model soundings develop MLCAPES to 2500-3000 j/kg along and ahead of the front by early afternoon. Another feature that we did not have on Tuesday that will be prevalent later today is a better mixed boundary layer with dry adiabatic flow peaking at 4-5kft. Stronger cells should have no issue pulling higher winds aloft to the surface as a result. While a few showers and storms will be possible through the morning...convection is expected to take off early this afternoon along the front and rapidly track E/NE. The CAMs have subtle variations on exactly when and where convection will initially fire...but the focus for greatest impacts will be east of US 31 across the eastern portion of the forecast area within a 3-4 hour window through roughly 21-22Z. BL shear and storm relative helicities will not be as impressive as values seen late Tuesday as Cristobal passed by...but they remain more than sufficient to support intense convection considering the instability present. Hodographs again support some low level veering and considering the tropical nature of the airmass...LCLs remain under 1000m ahead of the front Wednesday afternoon. All modes of severe weather likely to be in play again including tornadoes but as convection goes linear...damaging winds are likely to become the primary threat from storms as they race east into Ohio for some of the reasons mentioned above. The fast forward motion to storms at 40-45kts will only add to the potential damaging wind threat. In addition...winds will be gusty again for much of the day Wednesday with a tight surface pressure gradient and an 850mb jet rotating through the region. Think gusts peak at 40-45mph at times outside of any convection later today...especially over the eastern half of the forecast area. Have no plans for a Wind Advisory...but will likely highlight the gustier winds with an SPS. Temps...with the very warm start to the day...nudged temps at or above guidance across much of the region. Mid 80s should be easily attainable for all but the Wabash Valley. && .SHORT TERM /Tonight through Friday Night/... Issued at 342 AM EDT Wed Jun 10 2020 Forecast challenges are limited through the period as high pressure serves as the primary influence on weather across central Indiana. The strong upper wave that will help to bring the severe weather risk today will pivot off to the northeast tonight and Thursday towards James Bay before kicking east into the Canadian Maritimes by Friday night. With deep ridging aloft developing over the Rockies into west Texas...the upper level flow regime across the country will transition to a higher amplified pattern through the short term with a predominant dry northwest flow impacting the Ohio Valley through Friday night. This will advect a cooler and drier airmass into central Indiana for late week with abundant sunshine by day...mainly clear nights and pleasant temperatures. All convection will be northeast of the area by this evening but lower clouds may linger into the overnight as an area of moisture associated with a cold pool trails the upper low. Eventually...drier air will advect into the region as high pressure becomes firmly established. Will trend towards clearing skies by daybreak Thursday with a mostly sunny day to follow as subsidence increases over the area. A weak wave aloft passing to the north through the Great Lakes Thursday night may bring a brief increase in clouds before mainly clear skies reestablish Friday. The upper trough over the eastern U S will sharpen Friday night in response to a short wave diving through the eastern Great Lakes. A cold front will accompany the wave and drop through the region Friday night but with dynamics aloft displaced well to the northeast and low level moisture lacking...not expecting any rainfall associated with the front. Main impacts will be a subtle increase in clouds and a noticeable shift to north-northeast winds bringing a reinforcing shot of cooler and drier air into central Indiana for this weekend. Temps...low level thermals support seasonable temperatures for Thursday and Friday generally ranging from the upper 70s to the mid 80s. Lows will range from the mid 50s to near 60 tonight and Thursday night...with lower to mid 50s Friday night as the cooler airmass arrives. An overall model blend will work well through the period. && .LONG TERM /Saturday through Wednesday/... Issued at 254 AM EDT Wed Jun 10 2020 Long term portion of the forecast looks to be very quiet and mild with temperatures at or below normal. Guidance depicts an upper level low closing off and drifting about disconnected from the prevailing westerlies through much of the period. Differences exist between the Euro and GFS on positioning of this upper low, but both largely keep the area dry in the absence of any significant moisture source. Blend keeps pops largely out of the forecast, with the exception of a couple slight chances toward the very end of the period. Decided to go with a dry forecast until there's a more consistent signal for precip. && .AVIATION /Discussion for 10/18Z TAF Issuance/... Issued at 1217 PM EDT Wed Jun 10 2020 VFR outside of convection today, brief MVFR ceilings possible between 0Z and 04Z this evening. A broken line of convection is moving through central Indiana right now. Storms will impact IND before 18Z and BMG around 18Z. Afterwards, generally dry weather is expected with a brief period of MVFR ceilings possible late this evening. Winds will be southerly ahead of the rain and southwesterly afterwards. Frequent gusts in excess of 30kts through the afternoon with gusts to 20kts through tomorrow morning. && .IND WATCHES/WARNINGS/ADVISORIES... NONE. && SYNOPSIS...Ryan NEAR TERM...Ryan/KH SHORT TERM...Ryan LONG TERM...Nield AVIATION...White
Hazardous Weather Outlook National Weather Service Indianapolis IN 402 AM EDT Wed Jun 10 2020 INZ021-028>031-035>049-051>057-060>065-067>072-111000- Carroll-Warren-Tippecanoe-Clinton-Howard-Fountain-Montgomery-Boone- Tipton-Hamilton-Madison-Delaware-Randolph-Vermillion-Parke-Putnam- Hendricks-Marion-Hancock-Henry-Vigo-Clay-Owen-Morgan-Johnson-Shelby- Rush-Sullivan-Greene-Monroe-Brown-Bartholomew-Decatur-Knox-Daviess- Martin-Lawrence-Jackson-Jennings- Including the cities of Delphi, Flora, Williamsport, West Lebanon, Lafayette, West Lafayette, Frankfort, Kokomo, Attica, Covington, Veedersburg, Crawfordsville, Lebanon, Zionsville, Tipton, Fishers, Carmel, Noblesville, Anderson, Muncie, Winchester, Clinton, Newport, Rockville, Greencastle, Plainfield, Brownsburg, Danville, Indianapolis, Greenfield, Cumberland, New Castle, Terre Haute, Brazil, Clay City, Spencer, Martinsville, Mooresville, Greenwood, Franklin, Shelbyville, Rushville, Sullivan, Linton, Bloomfield, Bloomington, Nashville, Columbus, Greensburg, Vincennes, Washington, Loogootee, Shoals, Bedford, Mitchell, Seymour, Brownstown, and North Vernon 402 AM EDT Wed Jun 10 2020 This hazardous weather outlook is for central Indiana. .DAY ONE...Today and Tonight. Outlook: Severe thunderstorms developing this afternoon...especially over the eastern half of central Indiana. Strong winds gusting as high as 40 to 45 mph through early evening outside of showers and storms. Hazards: Damaging winds...tornadoes...torrential downpours and cloud to ground lightning. Strong winds possible outside of showers and storms as well with peak gusts to 40 to 45 mph. Timing: Best threat for severe storms from 1 pm to 5 pm. Strong wind gusts through early evening. Discussion: A strong upper level wave with an associated surface low and cold front will move through central Indiana this afternoon... triggering showers and thunderstorms. Severe storms are possible over the eastern half of the area this afternoon. High pressure will build in tonight with drier and much less humid conditions. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. Outlook: Dry weather is expected through early next week. Discussion: High pressure will build in with dry weather expected through early next week. Seasonable temperatures through Friday will cool to below normal over the weekend before rebounding next week. .SPOTTER INFORMATION STATEMENT... Spotter activation is likely this afternoon...especially over the eastern half of central Indiana. .STORM MOTION STATEMENT... The expected storm motion today is from the southwest at 50 to 55 mph. && More information, along with other weather, hydrological and climate information can be found at http://weather.gov/ind Ryan
The Indianapolis radar (KIND), 93 km away, was scanning. The volume nearest the first event began at 17:07 UTC.
13 thunderstorm wind, 1 hail, 1 strong wind, 1 high wind. Local standard time, as filed.
A tree of unknown size was downed on a house due to thunderstorm wind gusts.
Tree downed due to thunderstorm wind gusts at the 4600 block of South 700 East. Another tree was downed nearby.
Small tree limbs downed due to thunderstorm wind gusts along State Road 26. Pea sized hail also reported at this time.
Thunderstorm wind gust measured with a Davis Instrument.
Hail cracked wind shield.
Two inch diameter tree limbs downed due to thunderstorm wind gusts. 1/2 inch hail was also reported at this time.
A 70 mph thunderstorm wind gust was measured at this location.
A tree 8 inches in diameter was downed due to thunderstorm wind gusts.
A healthy blue spruce tree with a base of around 10 to 12 inches was uprooted due to thunderstorm wind gusts.
Ten power poles snapped due to thunderstorm wind gusts. A travel trailer was also overturned and slammed into the side of a house. Location is approximate.
Multiple tree limbs and various backyard items blown away by thunderstorm wind gusts. Live power line was wrapped around a trampoline. Tree was also reported on fire.
Four inch tree limbs downed due to thunderstorm wind gusts.
Healthy 10 inch diameter tree downed due to thunderstorm wind gusts and was blocking the road.
Large rotted limb downed due to strong gradient winds.
Several power lines and small trees downed due to thunderstorm wind gusts.
Tree approximately 2 feet in diameter downed onto house due to strong gradient winds. Home was located in Mooresville.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Indiana in 2020Every state in 2020This day in weather historyWarnings in Indiana, June 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 885544, 885543, 885545, 885555, 885542, 885546, 885547, 885548, 885549, 885551, 885550, 885552, 885553, 885557, 885554, 885556.