Campus Alert Archive
Iowa

Two Hawk Alerts in 48 Minutes During the Most Tornadoes Ever Recorded in Iowa in a Single Day in March: A Confirmed Tornado 9 Miles South of Iowa City Triggered the Second Warning

IAtornadoemergency notificationhigh confidence
Confirmed Threat

On Friday afternoon, March 31, 2023, 25 tornadoes touched down across Iowa — the most ever recorded in the state in a single day in March. The University of Iowa pushed two Hawk Alerts within 48 minutes: the first at approximately 4:27 PM CDT after the NWS Quad Cities issued a tornado warning for southwestern Johnson County valid until 4:45 PM CDT, and the second around 5:15 PM CDT after a confirmed tornado was located 9 miles south of Iowa City, moving northeast at 45 mph. The day produced nine EF2 tornadoes, one EF3, and one EF4 statewide. The University of Iowa main campus was spared a direct hit.

Alerts
2
Response
0 min
Killed
0
Injured
0
Institution
University of Iowa
Public R1 · IA
~31,000 studentsHawk Alert
Confirmed Timeline

Alert Sequence

2 messages in sequence · 2 verified verbatim

INITIAL ALERTSMS
Verified verbatimUniversity of Iowa Emergency Updates archive — Hawk Alert page for the 4:45 PM warning154 chars
HAWK ALERT: NWS has issued a tornado warning for SW Johnson County until 4:45 PM. Seek immediate shelter. See emergency.uiowa.edu for further information.
Pushed at approximately 4:27 PM CDT on March 31, 2023, when the NWS Quad Cities issued the first tornado warning for southwestern Johnson County valid until 4:45 PM CDT.
The 'SW Johnson County' geographic qualifier is unusual for Hawk Alert — the standard template just says 'Johnson County.' The 'SW' was preserved here because the initial warning polygon only covered the southwestern portion of the county.
Sent during the largest single-day tornado outbreak ever recorded in Iowa in March (25 tornadoes statewide), making this Hawk Alert the first of two pushed within 48 minutes.
UPDATESMS+48 min
Verified verbatimUniversity of Iowa Emergency Updates archive — Hawk Alert page for the 5:15 PM warning128 chars
HAWK ALERT: NWS Tornado Warning until 5:15pm includes parts of Johnson County. Seek immediate shelter. More: emergency.uiowa.edu
Pushed around 5:15 PM CDT on March 31, 2023, when the NWS Quad Cities issued a second tornado warning for parts of Johnson County after a confirmed tornado was located 9 miles south of Iowa City moving northeast at 45 mph.
Notably shorter and uses 'More:' rather than 'See...for further information' — Hawk Alert's compact-template variant, suggesting the system applies different SMS templates depending on warning urgency or operator selection.
Sent 48 minutes after the first Hawk Alert — a back-to-back tornado-warning sequence is rare for any single campus alert system in a single afternoon.
Context

Background

On Friday afternoon, March 31, 2023, the largest single-day tornado outbreak ever recorded in Iowa in March produced 25 tornadoes statewide — including nine EF2s, one EF3, and one EF4 — and put much of eastern Iowa under repeated tornado warnings. The University of Iowa pushed two Hawk Alerts within 48 minutes. The first, at approximately 4:27 PM CDT, relayed an NWS Quad Cities tornado warning for southwestern Johnson County valid until 4:45 PM CDT. The second, around 5:15 PM CDT, came after a confirmed tornado was located 9 miles south of Iowa City moving northeast at 45 mph; this warning placed the city of Iowa City itself inside the tornado-warning polygon. CAMBUS suspended bus service for the duration of the warnings per the university's severe-weather policy. The University of Iowa main campus was spared a direct hit — neither warning produced a confirmed touchdown in Iowa City — but the outbreak damaged homes and structures in nearby Hedrick (Keokuk County) and Coralville. The case is one of the rare instances where the Hawk Alert archive preserves verbatim text for two distinct tornado warnings issued during a single afternoon.
Analysis

Key Findings

Two Hawk Alerts pushed within 48 minutes on March 31, 2023, both during the largest single-day tornado outbreak ever recorded in Iowa in March (25 tornadoes statewide).
The two alerts used subtly different Hawk Alert SMS templates: the first uses 'See emergency.uiowa.edu for further information' (154 characters); the second uses the compact 'More: emergency.uiowa.edu' (128 characters) — a 26-character savings.
The second warning was triggered by a confirmed tornado on the ground 9 miles south of Iowa City moving northeast at 45 mph — the second alert came after the storm became a confirmed tornado, not just a radar-indicated rotation.
Outcome
Both tornado warnings expired with no confirmed tornado touchdown on the University of Iowa main campus. The broader March 31, 2023 outbreak produced 25 tornadoes in Iowa — the most ever for any day in March — including nine EF2s, one EF3, and one EF4 statewide. CAMBUS suspended service for the duration of the warnings per university severe-weather policy. No campus injuries or structural damage reported.
Provenance

Sources

  1. Official
    HAWK ALERT: NWS has issued a tornado warning for SW Johnson County until 4:45 PM (University of Iowa Emergency Updates)
    emergency.uiowa.edu
  2. Official
    HAWK ALERT: NWS Tornado Warning until 5:15pm includes parts of Johnson County (University of Iowa Emergency Updates)
    emergency.uiowa.edu
  3. Student Paper
    Severe weather watch: Tornado warning issued for Johnson County (The Daily Iowan)
    dailyiowan.com
  4. Report
    The Tornado Outbreak of March 31, 2023 (NWS Quad Cities)
    weather.gov
  5. News
    Iowa tornado damage today: March 31 storms damage homes, cities (We Are Iowa)
    weareiowa.com
  6. Report
    2023 Iowa Tornadoes (NWS Des Moines)
    weather.gov
  7. Official
    Hawk Alert (University of Iowa Department of Public Safety)
    police.uiowa.edu
Tags
IowaUniversity of IowaHawk Alerttornadotornado-warningsevere-weatherJohnson CountyIowa CityBig-TenMarch-2023-outbreak
Added May 2026Updated May 2026Via ingestion