During the daytime hours of March 15th, an area of rain moved through central Indiana with periods of freezing rain that impacted mainly elevated surfaces. The heaviest accumulation of ice occurred north of I-74 with some reports of icing up to a tenth of an inch.
Every event with a place to put it; 1 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.
During the daytime hours of March 15th, an area of rain moved through central Indiana with periods of freezing rain that impacted mainly elevated surfaces. The heaviest accumulation of ice occurred north of I-74 with some reports of icing up to a tenth of an inch. By the time the precipitation began to subside, power outages across the state were nearing 40,000 with some counties seeing up to 10% of total population without power.
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 Mar 15, 8:57 AM EST, 3 minutes earlier.
Area Forecast Discussion National Weather Service Indianapolis IN 957 AM EDT Mon Mar 15 2021 .Forecast Update... Issued at 957 AM EDT Mon Mar 15 2021 The northeastward progression of precipitation this morning is currently on track, so no changes to timing are needed. Current radar trends coincide with decent isentropic lift across the southeast two-thirds of central Indiana with dry air still to the northeast. Meanwhile, local reports and observations have generally been rain with freezing rain on elevated surfaces, and confidence remains low in just how much the evaporative cooling is going to inhibit the diurnal heating. Nonetheless, will continue to hold onto the wintry mix north of I-74 into the afternoon hours. Surface temperatures south of I-74 have been above freezing, but north of that line they remain below freezing. Winds remain strong out of the east with sustained speeds in the 15 to 22 mph range, gusting up to 30 mph. Updated grids have been sent. && .Short Term...(Today through Tuesday) Issued at 328 AM EDT Mon Mar 15 2021 Complex forecast this morning with multiple precipitation types likely across central Indiana through midday/early afternoon, especially central and north. Models have been consistent over the past several days depicting a substantial warm layer aloft, which should melt the vast majority of falling hydrometeors as precipitation moves into the area later this morning associated with the large vertically stacked low pressure system to our west, and the fairly potent frontogenetic forcing accompanying the occluded front. Do have some concern that dynamic cooling associated with this potent mesoscale forcing could erode the warm layer somewhat, but the more pressing concern is the depth and magnitude of the low level subfreezing layer. Model soundings have trended a bit shallower and less substantial with the cool layer, but still have significant concerns that wetbulbing/evaporational cooling will reinforce this cool layer and shift what would ordinarily be freezing rain conditions to sleet conditions. In all likelihood, appears that there will be a period of mainly sleet, perhaps some brief freezing rain early in the event, transitioning to a rain/sleet mix for a time before conditions eventually transition to all rain. The good news is that recent warmth has drastically increased the likelihood that any freezing rain will struggle to accumulate anywhere but elevated surfaces, and in any case, FZRA should be brief enough that light glazes at most occur on those surfaces. Light sleet accumulations may occur, but will also have relatively warm ground helping to limit impacts. Still have some details to work out, but expect that messaging via typical products and perhaps an SPS will be sufficient for the minor impacts expected at this time. Will see a brief break in widespread precipitation for a few hours late this afternoon into the evening before an area of rain associated with a lobe of the upper level low moves through the area, especially the northern half. Have increased initialized pops to account for this, as most all guidance is in good agreement here. Temperatures will range quite a bit, especially today, and there is quite a bit of uncertainty, especially with how heavier portion of the precip band may cool surface temperatures and what the exact northward extent of the surface warm front ends up being. Generally expect highs today to range from the upper 30s to upper 40s, with only a few degrees drop tonight. && .Long Term...(Tuesday night through Sunday) Issued at 328 AM EDT Mon Mar 15 2021 Highly amplified flow aloft will maintain the active pattern across the Ohio Valley through late this week. A strong storm system set to track through the region Wednesday night and Thursday will bring widespread rainfall and embedded thunder Model soundings suggest that lower clouds may be stubborn in their departure Tuesday night...with light flow as ridging at the surface and aloft sets up over the region. A sharp but shallow low level inversion will be slow to weaken but progressively drier air will filter into the boundary layer early Wednesday and should enable scattering of the deck to commence. Focus will quickly turn to a strong upper low kicking into the southern Plains Wednesday morning with an associated surface low. Ridging ahead of the system will draw moist southerly air north into the Ohio Valley with highs into the 60s on Wednesday. The storm system will spread east through Thursday with an increasing threat for severe weather over the Tennessee and lower Ohio Valleys into the deep south late Wednesday through Wednesday night. Further north across central Indiana...minimal instability will limit convective coverage. The presence of strong moisture advection courtesy of increased 850mb flow across the Tennessee and lower Ohio Valleys in tandem with deeper lift and diffluence aloft supports widespread and locally heavy rainfall moving into the area Wednesday night as the surface low approaches from the southwest. Modest BL shear does support the possibility of embedded storms with perhaps a small hail threat primarily focused Wednesday night and Thursday morning as the surface wave tracks across the Ohio Valley. The combination of a strong easterly low level jet transporting deep moisture westward to the north of the low pressure with a noticeable trowal feature pivoting into the area Thursday will support widespread rain persisting for much of the day even as the surface wave moves away from the region. A strong N/NE flow will make for a raw...damp and windy day across the forecast area with temperatures in the upper 40s to mid 50s. Rain will continue through Thursday evening before ending overnight as strong high pressure over the Great Lakes begins to exert its influence and advect much drier air south into central Indiana. Low levels may cool enough to enable a few snowflakes to mix in across the northern half of the forecast area Thursday night before precipitation ends. The remainder of the extended will transition back to a dry and seasonable weather regime aided by the strong high pressure ridge moving southeast into the northeast U S by late weekend. Model soundings and RH progs show deep subsidence present Friday through the weekend with mostly clear skies expected for the forecast area. Surface flow will gradually veer to southerly by late next weekend with the passage of the center of the high as daytime temperatures rise from the upper 40s and lower 50s Friday to the lower 60s by Sunday. && .Aviation...(12Z TAF Issuance) Issued at 640 AM EDT Mon Mar 15 2021 IMPACTS: -Strong gusty easterly winds throughout much of the period. -Period of RAPL likely at LAF and perhaps IND. Eventually transitioning to rain. -Deteriorating ceilings reaching IFR by tonight. DISCUSSION: Strong gusty winds are already ongoing across the area, with easterly winds generally 15-25KT gusting to 25-35KT. This will continue throughout the day and into this evening before winds relax overnight. Precipitation is expected to overspread the area today, with dry low levels contributing to significant wetbulb cooling and producing sleet or a sleet/rain mix at LAF and perhaps IND for a time. The other sites are more likely to remain rain, and the trend will be for precipitation to gradually change to rain where it starts frozen or as a mix. Additional precipitation is expected overnight primarily over the northern half of the area, but should be all liquid. This will be accompanied by IFR or worse ceilings as a portion of the upper level low moves overhead. && .IND WATCHES/WARNINGS/ADVISORIES...None. && Update...TDUD Short Term...Nield Long Term...Ryan Aviation...Nield
Hazardous Weather Outlook National Weather Service Indianapolis IN 353 AM EDT Mon Mar 15 2021 INZ021-028>031-035>049-051>057-062>065-071-072-160800- 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-Monroe-Brown-Bartholomew-Decatur-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, Bloomington, Nashville, Columbus, Greensburg, Seymour, Brownstown, and North Vernon 353 AM EDT Mon Mar 15 2021 This hazardous weather outlook is for central Indiana. .DAY ONE...Today and Tonight. A wintry mix of precipitation is expected for at least a brief period today, with the most prolonged chances for wintry precipitation north of a Terre Haute to Greensburg line. Sleet and some brief freezing rain will change over to rain as the day progresses. Warm ground temperatures will help to limit impacts from this precipitation. Winds will gust up to 35 MPH at times through the day. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. A few thunderstorms will be possible Wednesday night into Thursday across portions of the area. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated. && More information, along with other weather, hydrological and climate information can be found at http://weather.gov/ind INZ060-061-067>070-160800- Sullivan-Greene-Knox-Daviess-Martin-Lawrence- Including the cities of Sullivan, Linton, Bloomfield, Vincennes, Washington, Loogootee, Shoals, Bedford, and Mitchell 353 AM EDT Mon Mar 15 2021 This hazardous weather outlook is for central Indiana. .DAY ONE...Today and Tonight. No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday. Winds will occasionally gust up to 35 mph during the day Monday. A few thunderstorms are possible Wednesday night into Thursday. An isolated strong storm cannot be ruled out Wednesday night. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated. && More information, along with other weather, hydrological and climate information can be found at http://weather.gov/ind
Special Weather Statement National Weather Service Indianapolis IN 408 AM EDT Mon Mar 15 2021 INZ021-028>031-035>049-051>057-062>065-071-072-151500- 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-Monroe-Brown-Bartholomew-Decatur-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, Bloomington, Nashville, Columbus, Greensburg, Seymour, Brownstown, and North Vernon 408 AM EDT Mon Mar 15 2021 ...Period of Wintry Mix Likely Today... Widespread precipitation is expected to overspread central Indiana later this morning, continuing into the afternoon hours. Dry and cool air near the surface is expected to promote a period of sleet, perhaps mixed with rain, or briefly freezing rain, across portions of central Indiana, especially along and north of a Terre Haute to Greensburg line. This mix of precipitation types will last longest the further north you are. Any freezing rain is likely to be brief and unlikely to accumulate on anything but elevated surfaces due to warm ground temperatures. Sleet may accumulate during the heaviest portion of the precipitation, but will also have warm ground temperatures helping to melt it as it falls. There will be some potential for a few slick spots on roadways during the heaviest precipitation later this morning into the early afternoon hours. Exercise caution if traveling today. NIELD
The national radar mosaic for the moment the first event began.
1 winter weather. Local standard time, as filed.
Power lines downed and large pine trees snapped mid-way in vicinity of 700 West from 300 North to 100 North during a freezing rain event.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Indiana in 2021Every state in 2021This day in weather historyWarnings in Indiana, March 2021
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: 938442.