HUM ENHANCED Risk 20260721

Update No. 4

Posted 10 am on Tuesday, 21 July 2026

The National Weather Service has narrowed and moved the expected severe-weather timing earlier. A few strong thunderstorms may occur through approximately Noon. The primary se

vere-weather window for damaging winds, large hail and isolated tornadoes is now expected from approximately Noon to 7:00 PM.

Damaging winds remain the primary and Significant threat. Heavy rainfall and localized flooding may remain possible from approximately 2:00 PM to 9:00 PM. NWS-provided future radar guidance shows a line of storms potentially reaching Clinton County around 2:00–3:00 PM, although the exact arrival time and storm coverage may change.

Complete any remaining preparations now and be ready to move into sturdy shelter when a warning is issued or conditions rapidly become unsafe.

Slight timing adjustment: the storm line may reach Clinton County shortly before 2:00 PM and clear the county after 3:00 PM. This does not rule out additional thunderstorms later this afternoon or evening.

 - - - END UPDATE No. 4 - - - -

Update No. 3

Posted 6 am on Tuesday, 21 July 2026

The latest forecast increases the tornado concern for southeastern Clinton County, where there is now a 5–10% chance of a tornado occurring within 25 miles of a location. The northeastern corner of the county—including Kingman, New Burlington and Lumberton—remains in the 2–5% tornado probability area. Across Clinton County, there is a 30–45% chance of severe wind gusts of 58 mph or greater and a 15–30% chance of hail one inch or larger within 25 miles of a location. Damaging winds remain the primary threat, and numerous thunderstorms capable of producing dangerous cloud-to-ground lightning are expected. Southern and eastern portions of the county remain under an Enhanced Risk (3/5), while northern and western portions remain under a Slight Risk (2/5). A few strong storms may occur from approximately 9:00 AM–2:00 PM, with the primary severe-weather window remaining 2:00–9:00 PM. Heavy rainfall and localized flash flooding also remain possible, and morning storms may affect where and how extensively severe storms develop later today.

Probability versus Timing Chart:

SPC Day 1 Timing Guidance – Wilmington, Ohio: This chart provides hour-by-hour estimates of when severe-weather hazards are most likely near Wilmington on the day of the event. The probability of damaging thunderstorm winds peaks above 40% between approximately 1:00 and 2:00 PM. The tornado probability begins increasing after 10:00 AM and remains elevated through approximately 8:00 PM. The chart helps identify the most likely periods for damaging winds, tornadoes and hail, but it does not guarantee that storms will occur at a specific time or location. Residents should remain weather aware throughout the full threat period and be prepared to act immediately when warnings are issued.

SLIGHT Risk: Scattered severe thunderstorms possible. ENHANCED Risk: Numerous severe thunderstorms possible.

MARGINAL Risk: Up to 5% chance of a tornado within 25 miles of your location. SLIGHT Risk: 5-10% chance of a tornado within 25 miles of your location.

ENHANCED Risk: 30-45% chance of severe wind gusts (58 mph or greater) within 25 miles of your location.

SLIGHT Risk: 15-30% chance of 1" or larger hail within 25 miles of your location.

Elevated Risk: Numerous thunderstorms with dangerous cloud-to-ground lightning expected.

Limited Risk: Isolated flash floods possible. Most flooding will be localized to areas that can experience rapid runoff with heavy rainfall. Elevated Risk: Scattered flash floods possible, some potentially significant. Most vulnerable are urban areas, roads, small streams, and washes.

 - - - END UPDATE No. 3 - - - -

Update No. 2

Posted 3 pm on Monday, 20 July 2026

The overall severe weather threat for Tuesday remains largely unchanged, with southern and eastern Clinton County in an Enhanced Risk (3/5) and northern and western portions in a Slight Risk (2/5). Damaging winds remain the primary concern, while large hail, an isolated tornado and localized flooding are also possible. The main change is improved timing: a few strong storms may occur between 6:00 AM and 2:00 PM, followed by the main severe weather window from approximately 2:00 PM to 9:00 PM. NWS Wilmington also added greater emphasis on heavy rainfall and the potential for localized flash flooding. Morning storms may affect how later storms develop, so the exact location and severity of the afternoon threat remain uncertain.

 - - - END UPDATE No. 2 - - - -

Update No. 1

Posted: 6:30 am on Monday, 20 July 2026

SUMMARY

The severe weather outlook for Tuesday, 21 July remains largely unchanged. Approximately the southeastern half of Clinton County remains in an ENHANCED Risk—Level 3 of 5—including Sabina, New Vienna, Martinsville, eastern and southern Wilmington, Cuba, Midland, Westboro and Blanchester. The remainder of the county remains in a SLIGHT Risk—Level 2 of 5—including Clarksville, Burlington, western and northern Wilmington, Lumberton and Port William.

Damaging straight-line winds remain the primary concern. The damaging-wind probability is 45% across the Enhanced Risk portion of the county and 30% across the Slight Risk portion. The entire county remains within a 15% probability for damaging hail, while the probability for an isolated tornado ranges from 2% to 5%. Numerous severe thunderstorms are expected across the broader Ohio Valley region, with damaging wind identified as the most likely widespread hazard.

THREATS

1. Damaging Straight-Line Winds – Significant Threat: Severe storms may produce concentrated areas of downed trees and power lines, blocked roads, power outages and possible structural damage. The highest probability is across the southern and eastern portions of Clinton County, but damaging winds are possible anywhere in the county.

2. Isolated Tornadoes – Limited Threat: The entire county remains within a 2% to 5% tornado probability. A few tornadoes may develop if individual supercells remain separate or if rotating circulations develop within an organized line of storms.

3. Large Hail – Limited Threat: All of Clinton County remains within a 15% probability for damaging hail. Isolated storms may produce hail capable of damaging vehicles, crops and outdoor property.

4. Heavy Rain and Localized Flooding – Limited Threat: Torrential rainfall may produce isolated flash flooding, standing water and drainage problems, particularly where storms repeatedly affect the same locations.

TIMING

The primary severe weather window remains Tuesday afternoon through Tuesday evening, although storms could continue into the nighttime hours. A more specific arrival window for Clinton County is not yet available, and the exact timing will depend on how storms develop and organize across the Ohio Valley.

Additional Comments

The Storm Prediction Center indicates that storms may develop as a mixture of individual supercells and one or more bowing lines. This suggests that hail or isolated tornadoes may be possible with individual storms, while damaging winds could become the more widespread concern as storms organize into lines. Forecast confidence remains highest for damaging winds, while confidence in the tornado, hail and flooding threats remains lower.  

The dividing line between the Enhanced and Slight Risk areas should not be treated as a firm boundary. Severe storms can cross both portions of the county, and everyone should prepare for the possibility of damaging winds and power outages.

Use Monday to secure tents, canopies, trampolines, lawn furniture, signs and other loose outdoor items. Review where you will take shelter, how you will receive warnings and what you will do if electrical service or road access is disrupted. Outdoor event organizers should be prepared to suspend activities and move people into sturdy shelter before severe weather arrives.

This Heads Up Message is for advance planning and is not a watch or warning.

Plan. Prepare. Protect.

Prepare Now Keywords [link]

• Severe Wx

• Power

• Tornado

- - - - END UPDATE No. 1 - - - -

Posted: Sunday, 19 July 2026 | 11:45 AM

Summary

Clinton County is included in an ENHANCED Risk—Level 3 of 5—for severe thunderstorms on Tuesday, 21 July. Numerous severe thunderstorms may develop across the Ohio Valley as a strong weather system and cold front move through the region. Damaging straight-line winds are expected to be the primary concern.

The National Weather Service indicates that severe thunderstorms are likely Tuesday afternoon into the evening, with the greatest impacts expected along and southeast of Interstate 71. This includes Clinton County. Storms may produce downed trees and power lines, possible structural damage, large hail, isolated tornadoes and localized flooding.

Threats

1. Damaging Straight-Line Winds – Significant Threat: Numerous downed trees and power lines are possible, along with scattered structural damage. Storms may organize into fast-moving lines or bowing segments capable of producing corridors of wind damage.

2. Isolated Tornadoes – Limited Threat: Tornadoes will be possible with any storms that remain separate or develop rotation before forming into a larger line. Specific tornado threat areas will be included with the Monday morning update.

3. Large Hail – Limited Threat: Isolated storms may produce hail large enough to damage vehicles, crops and outdoor property.

4. Heavy Rain and Localized Flooding – Limited Threat: Thunderstorms may produce torrential rainfall, resulting in isolated flash flooding or drainage problems in locations receiving repeated storms.

Timing

The primary severe weather window is currently expected Tuesday afternoon through Tuesday evening, although some storms could occur earlier in the day or continue into the nighttime hours. A more specific arrival window for Clinton County is not yet available.

Additional Comments

This remains a Day 3 forecast, and changes to the risk area, storm timing and individual threats remain possible. Thunderstorms crossing the region Monday night or Tuesday morning could affect how much instability develops Tuesday afternoon and may shift the timing or severity of the later storms.

The exact storm mode also remains uncertain. Individual storms could initially support hail or tornadoes, but the overall environment favors storms eventually organizing into one or more lines with damaging winds becoming the primary concern.

Residents, businesses, special-event organizers and public safety partners should use Monday to review severe weather procedures and plans for possible power outages, blocked roads and disrupted outdoor activities. This Heads Up Message is for advance planning and is not a watch or warning.

Plan. Prepare. Protect.