Alert archive / Ohio

Weather alerts in Ohio, 2015

2,499 weather alerts in 2015, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered any part of the state, so the counties below add up to more than the state.

Weather alerts by county

Each county as a circle sized by its count in 2015. Tap one for its archive.

Alerts
2,499
Warnings
859
Watches
135
Advisories
528
Busiest month
June630 alerts
Busiest day
July 14, 2015131 alerts

Over time

By month

Warning verification

How often warnings here had a storm report inside them, and how much warning the reports had.

4 of 26 tornado warnings covering Ohio in 2015 had a tornado report inside them; 2 of 6 tornado reports fell inside a warning, on average 11 minutes after it went out.

Ohio, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings26485%633%11 min
Severe thunderstorm warnings39126831%75973%19 min
Flash flood warnings654137%10188%122 min

Each office's whole area, 2015

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Cleveland, OH: tornado warnings90100%0
NWS Cleveland, OH: severe thunderstorm warnings1127731%15878%16 min
NWS Cleveland, OH: flash flood warnings30100%0
NWS Wilmington, OH: tornado warnings18667%1377%9 min
NWS Wilmington, OH: severe thunderstorm warnings21813638%58771%19 min
NWS Wilmington, OH: flash flood warnings301260%3479%59 min
NWS Northern Indiana: tornado warnings20100%20%
NWS Northern Indiana: severe thunderstorm warnings1077134%25756%20 min
NWS Northern Indiana: flash flood warnings17571%1889%70 min
NWS Charleston, WV: tornado warnings5180%425%4 min
NWS Charleston, WV: severe thunderstorm warnings1248928%31384%28 min
NWS Charleston, WV: flash flood warnings705521%21489%98 min
NWS Pittsburgh, PA: tornado warnings13192%250%5 min
NWS Pittsburgh, PA: severe thunderstorm warnings17413324%50584%19 min
NWS Pittsburgh, PA: flash flood warnings493822%14091%106 min

An office's figures cover every county it serves, including across state lines.

Verified by the Iowa Environmental Mesonet's Cow, which matches each storm-based warning with the local storm reports inside its polygon while it was in force, within 15 km of its edge: a tornado warning counts as verified on a tornado report, a severe thunderstorm warning on hail of 1 inch or more, a gust of 58 mph or more, or wind damage, a flash flood warning on a flash flood report. The false alarm ratio is the share of warnings with no such report; "inside a warning" is the probability of detection, the share of reports that fell inside one; lead time runs from the warning's issue to each report inside it, counting zero for a report that came first. A warning with no report is not proof nothing happened: reports come from spotters, the public and damage surveys, and are thin where few people live.

The alerts

2,499 alerts are too many to list on one page. Narrow it to a product above, to a month in the chart, or to a county.

By product

Every kind of product issued here, grouped by hazard. Each opens the same place narrowed to that product.

By county

Every county with at least one alert. A county page lists each alert that covered it.

48 more counties

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordThe radar archive20142016

Sources

National Weather Service watches, warnings, advisories and statements from the Iowa Environmental Mesonet's VTEC archive, which reconstructs tornado, severe thunderstorm, flash flood and marine warnings back to 1986 from the NWS text archive. Storm Prediction Center watches and mesoscale discussions from SPC's archive through the Mesonet. County centers from the US Census Bureau. Warning verification from the Mesonet's Cow. Rebuilt daily.