Isolated thunderstorms developed across portions of northern Illinois during the afternoon of April 19th, producing mainly large hail.
Every event with a place to put it. 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 LOT wrote it up.
Isolated thunderstorms developed across portions of northern Illinois during the afternoon of April 19th, producing mainly large hail.
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 Chicago, IL wrote its last area forecast discussion before the first event at Apr 19, 1:47 PM CST, 45 minutes earlier.
Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 247 PM CDT Wed Apr 19 2023 .SHORT TERM... Issued at 247 PM CDT Wed Apr 19 2023 Through Thursday night... Primary focus is thunderstorm chances and timing. Additional forecast concerns and challenges include warm front location/ movement north tonight and strong southerly winds Thursday. Isolated thunderstorms continue across parts of west central IL this afternoon and have been weakening as they move east into a drier airmass. However, this isolated activity may persist through the late afternoon across northeast IL. Difficult to determine what areas would be most likely to see this activity given the expected low coverage and higher uncertainty and for now have low chance pops moving east through 00z. An isolated strong/severe storm is possible. Focus for convection tonight will shift further west and may move across the northwest or northern cwa in the predawn hours, likely in a weakening phase. Low confidence during this time period as well but maintained similar pops from previous forecast, increasing to high chance across the northwest by 12z Thursday. Depending on how well any storms maintain their intensity, there may be a strong/severe storm with this activity, mainly across the far northwest cwa. Convective trends on Thursday will likely be dependent on how the early morning activity evolves and where it decays. The best chance for thunderstorms seems like it will be in the afternoon or early evening, ahead of the cold front. But activity earlier in the day, perhaps some redevelopment by mid/late morning on any outflow from the early morning activity, is possible. Thus, some chance pop mention is still needed until trends become more clear. At this point highest pops are in the late afternoon/early evening. Precip looks to end across most of northern IL, but some continued chances are needed Thursday night/early Friday morning for areas east of I-57. Some of the short term guidance has been showing the front stalling or even moving a little further south across the I-88 corridor. The front is showing up on radar and currently drifting slowly south. It will likely stall and meander through early evening but confidence is low for when it will lift back north tonight. Temps at ORD have dropped about 5 degrees in the past hour and updates to temps and winds, based on the frontal location, can be expected this evening. South of the front, temps are well into the 70s and some locations may tag 80 late this afternoon. Lows south of the front generally in the upper 50s, perhaps mid/upper 40s north of the front this evening, then rising temps overnight, if the the front does move back north. Highs on Thursday likely in the 70s, highest across the southeast cwa where temps may tag 80. Southerly winds may gust as high as 40 to 45 mph on Thursday, especially south of I-80. But confidence is still low for how strong the winds will become based on convective trends. cms && .LONG TERM... Issued at 137 PM CDT Wed Apr 19 2023 Friday through Wednesday... In the wake of a cold front Thursday night, a brief window of southwesterly winds and filtered sunshine is expected Friday before a secondary cold front sweeps through Friday evening. Temperatures Friday hence have the opportunity to shoot into the mid 60s before the reinforcing shot of cold air arrives. Depending on just how how warm surface temperatures verify, a gusty shower or thunderstorm cannot be ruled out along the front during the evening. Thereafter, ensemble model guidance is in excellent agreement that deep cyclonic upper-level flow will meander through the Great Lakes leading to another period of below-average temperatures. Highs Saturday and Sunday are expected to remain in the mid to upper 40s with brisk west-northwesterly winds. Periods of showers are a good bet near any embedded vort lobe, with perhaps the best signal Saturday afternoon. Thereafter, ensemble model guidance provides a soft signal for gradually warming temperatures into next week. Borchardt && .AVIATION... For the 18Z TAFs... The main aviation weather concerns through the period include: * Wind trends at the Chicago terminals mid to late this afternoon into this evening. Currently have the lowest confidence in wind directions at KORD from 21 through 03Z this afternoon and evening. * Continued threat for a few isolated to widely scattered thunderstorms in and near the terminals this afternoon. Low confidence on a storm moving over a given terminal. * LLWS tonight. * Another threat for a period of thunderstorms mid to late Thursday afternoon. A complicated wind and convective forecast is in store this afternoon and evening as a warm front across central IL lifts northward into the Chicago metro. Winds to the south of this front will become breezy from the south, while north of the front breezy easterly winds will persist. The timing in which this front (and associated southerly wind shift) shifts over the terminals late this afternoon and early evening remains of low confidence (most notably at KORD). The possibility even exists for the winds north of the approaching warm front to slow down the arrival of the front, and potentially resulting in a longer period of east to northeasterly winds at KORD into this evening. This possibility would likely be higher if any afternoon isolated to widely scattered thunderstorms develop over southern WI and far northern IL. Currently the confidence with both the wind forecast, and the potential for any storms near the terminals late this afternoon into early this evening remains of low confidence. By late this evening, a 50 knot LLJ will support LLWS through much of the night while the warm front should finally clear the Chicago metro overnight with gusty SSW winds developing into Thursday morning. Gusty SSW winds are then expected through the day Thursday. While we continue to advertise a dry period of weather in the TAFs late tonight, we will have to keep an eye on the trends with severe convection to our west this evening. There is a non-zero threat that the weakening remnants from this activity could try to shift into parts of northwestern IL very late tonight into early Thursday morning. Currently this potential is too low for a formal mention in the TAFs. Our next potential threat for a period of thunderstorms looks to come Thursday afternoon in association with an approaching cold front. Currently appears the best timing for the Chicago area terminals would be mid to late Thursday afternoon. A PROB30 group for TSRA from 21 to 00z has been added to the ORD and MDW 30 hour TAFs to cover this possibility. KJB && .LOT WATCHES/WARNINGS/ADVISORIES... IL...None. IN...None. LM...None. && Visit us at weather.gov/chicago Follow us on Facebook, Twitter, and YouTube at: www.facebook.com/NWSChicago www.twitter.com/NWSChicago www.youtube.com/NWSChicago
Hazardous Weather Outlook
National Weather Service Chicago/Romeoville IL
227 PM CDT Wed Apr 19 2023
ILZ003>006-008-010>013-019>021-023-032-033-039-103>108-INZ001-002-
010-011-019-201930-
Winnebago-Boone-McHenry-Lake IL-Ogle-Lee-De Kalb-Kane-DuPage-
La Salle-Kendall-Grundy-Kankakee-Livingston-Iroquois-Ford-
Northern Cook-Central Cook-Southern Cook-Northern Will-
Southern Will-Eastern Will-Lake IN-Porter-Newton-Jasper-Benton-
227 PM CDT Wed Apr 19 2023 /327 PM EDT Wed Apr 19 2023/
This Hazardous Weather Outlook is for portions of North Central
Illinois...Northeast Illinois and Northwest Indiana.
.DAY ONE...Tonight.
Weather hazards expected...
Limited Thunderstorm Risk...with an associated:
Limited Hail Risk...up to ping pong ball size, or 1.5 inches
diameter.
DISCUSSION...
An isolated thunderstorm or two may develop this afternoon in
northern Illinois. If a thunderstorm develops, it may produce
damaging hail as large as ping pong balls. Most areas will stay
dry.
Additional thunderstorms may approach Interstate 39 after midnight
tonight with a threat for gusty winds. Severe weather is not
expected overnight.
.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.
Thursday...
Limited Severe Thunderstorm Risk.
Limited Flooding Risk.
Limited Non Thunderstorm Wind Risk.
Saturday and Sunday nights...
Limited Freeze Risk.
DISCUSSION...
A period or two of thunderstorms may materialize Thursday with a
threat for damaging hail and winds.
Southerly winds could gusts to around 40 mph Thursday afternoon.
.SPOTTER INFORMATION STATEMENT...
Spotters are not anticipated at this time.
GENERAL STORM MOTION OF THE DAY:
Moving toward the northeast at 35 mph.
LMZ740>745-201930-
Winthrop Harbor to Wilmette Harbor IL-
Wilmette Harbor to Northerly Island IL-
Northerly Island to Calumet Harbor IL-
Calumet Harbor IL to Gary IN-Gary to Burns Harbor IN-
Burns Harbor to Michigan City IN-
227 PM CDT Wed Apr 19 2023
This Hazardous Weather Outlook is for portions of the Illinois
nearshore waters of Lake Michigan and the Indiana nearshore
waters of Lake Michigan.
.DAY ONE...Tonight.
Weather hazards expected...
Limited Thunderstorm Risk...with an associated:
Limited hail risk...up to 1.5 inches in diameter.
.DAYS TWO THROUGH SEVEN...Thursday through Tuesday.
Thursday...
Hazardous conditions for small craft are likely.
Limited Severe Thunderstorm Risk.
Saturday...
Hazardous conditions for small craft are likely.
Borchardt
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www.youtube.com/nwschicagoThe Chicago radar (KLOT), 81 km away, was scanning. The volume nearest the first event began at 20:30 UTC.
23 hail. Local standard time, as filed.
A windshield was broken on Interstate 39 near mile marker 74 due to hail which was estimated to be ping pong ball size.
A photo was shared of golf ball size hail near Route 251 and 46th Road.
A photo showed quarter size hail near Stroble Avenue and 14th Street.
Photos showed golf ball size hail near Meridan.
A photo shared on social media showed hail at least golf ball size north of Earlville.
At least quarter size hail was reported in Sublette.
Hail to quarter size was reported near Route 251 and Herman Road.
A photo shared on social media showed half dollar size hail northeast of Earlville.
Quarter size hail was reported near Route 71 and Route 47.
Dime to quarter size hail was reported near Route 34 and Game Farm Road.
Golf ball size hail was reported in west Joliet.
Half dollar size hail was reported near Caton Farm Road and County Line Road.
Quarter size hail was reported near Ridge Road and Holt Road.
Quarter size hail was reported at Joliet Junior College.
Photos shared on social media showed quarter size hail near 9000 North Road and 3500 West Road, west of Manteno.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Illinois in 2023Every state in 2023This day in weather historyWarnings in Illinois, April 2023
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: 1085613, 1085610, 1085612, 1085614, 1085611, 1085615, 1085616, 1085617, 1085618, 1085619, 1085620, 1086340, 1086341, 1086345, 1086347, 1086349, 1086350, 1086351, 1086352, 1086356, 1086359, 1086361, 1086362.