Alert archive / New York / Ontario County

Weather alerts in Ontario County, New York, 2021

103 weather alerts in 2021, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Ontario County and its neighbors

Each county as a circle sized by its count in 2021. Tap one for its archive.

Alerts
103
Warnings
30
Watches
11
Advisories
20
Busiest month
July22 alerts
Busiest day
June 21, 20218 alerts

Over time

By month

Warning verification

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

Ontario County, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings171229%1580%26 min
Flash flood warnings10100%0

Each office's whole area, 2021

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Buffalo, NY: tornado warnings20100%10%
NWS Buffalo, NY: severe thunderstorm warnings1147633%22093%27 min
NWS Buffalo, NY: flash flood warnings241346%32100%85 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

Every alert, in the order issued. Times are local, Eastern Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 20, 8:01 AM ESTSpecial Weather StatementBUF59 min
Jan 22, 10:18 AM ESTSpecial Weather StatementBUF72 min
Jan 25, 3:22 AM ESTWinter Weather AdvisoryBUF51 hr
Jan 26, 11:32 AM ESTSpecial Weather StatementBUF58 min
Jan 28, 3:32 AM ESTWinter Weather AdvisoryBUF24 hr
Feb 1, 3:45 AM ESTWinter Weather AdvisoryBUF48 hr
Feb 2, 2:07 PM ESTWinter Storm WarningBUF20 hr
Feb 13, 2:53 PM ESTWinter Storm WatchBUF24 hr
Feb 14, 3:12 PM ESTWinter Storm WarningBUF42 hr
Feb 15, 8:06 PM ESTMesoscale DiscussionSPC5 hr
Feb 21, 1:41 PM ESTWinter Weather AdvisoryBUF33 hr
Feb 22, 7:14 AM ESTSpecial Weather StatementBUF61 min
Feb 28, 6:44 PM ESTWind AdvisoryBUF30 hr
Mar 1, 3:44 PM ESTSpecial Weather StatementBUF46 min
Mar 1, 4:32 PM ESTSpecial Weather StatementBUF43 min
Mar 11, 9:30 PM ESTSpecial Weather StatementBUF60 min
Mar 11, 10:31 PM ESTSpecial Weather StatementBUF44 min
Mar 25, 2:12 PM EDTWind AdvisoryBUF29 hr
Mar 28, 4:00 AM EDTWind AdvisoryBUF27 hr
Mar 28, 12:48 PM EDTSpecial Weather StatementBUF57 min
Mar 28, 1:46 PM EDTSpecial Weather StatementBUF119 min
Mar 30, 2:51 PM EDTWinter Storm WatchBUF13 hr
Mar 31, 3:57 AM EDTWinter Weather AdvisoryBUF16 hr
Apr 1, 1:45 PM EDTSpecial Weather StatementBUF60 min
Apr 1, 2:47 PM EDTSpecial Weather StatementBUF58 min
Apr 1, 3:47 PM EDTSpecial Weather StatementBUF58 min
Apr 1, 4:43 PM EDTSpecial Weather StatementBUF62 min
Apr 28, 1:06 PM EDTMesoscale DiscussionSPC114 min
Apr 29, 2:24 PM EDTWind AdvisoryBUF31 hr
May 10, 1:06 PM EDTFrost AdvisoryBUF17 hr
May 25, 3:44 PM EDTSevere Thunderstorm WarningBUF32 min
May 26, 12:16 PM EDTMesoscale DiscussionSPC119 min
Jun 13, 11:01 PM EDTSpecial Weather StatementBUF44 min
Jun 20, 9:55 PM EDTSevere Thunderstorm WarningBUF39 min
Jun 21, 5:48 AM EDTSevere Thunderstorm WarningBUF42 min
Jun 21, 6:25 AM EDTSevere Thunderstorm WarningBUF50 min
Jun 21, 12:31 PM EDTSevere Thunderstorm WatchSPC7 hr
Jun 21, 3:18 PM EDTSevere Thunderstorm WarningBUF57 min
Jun 21, 3:47 PM EDTMesoscale DiscussionSPC58 min
Jun 21, 3:55 PM EDTSevere Thunderstorm WarningBUF50 min
Jun 21, 3:58 PM EDTSevere Thunderstorm WarningBUF47 min
Jun 26, 1:36 PM EDTHeat AdvisoryBUF30 hr
Jun 28, 9:38 AM EDTHeat AdvisoryBUF10 hr
Jun 28, 2:03 PM EDTHeat AdvisoryBUF30 hr
Jun 29, 2:33 PM EDTMesoscale DiscussionSPC117 min
Jun 30, 11:04 AM EDTMesoscale DiscussionSPC116 min
Jun 30, 11:47 AM EDTSevere Thunderstorm WatchSPC7 hr
Jun 30, 2:15 PM EDTSevere Thunderstorm WarningBUF35 min
Jul 2, 3:13 PM EDTMesoscale DiscussionSPC92 min
Jul 5, 9:14 PM EDTMesoscale DiscussionSPC2 hr
Jul 6, 11:32 AM EDTSevere Thunderstorm WarningBUF43 min
Jul 6, 12:21 PM EDTSevere Thunderstorm WarningBUF54 min
Jul 7, 6:49 AM EDTSpecial Weather StatementBUF41 min
Jul 9, 12:32 PM EDTSpecial Weather StatementBUF43 min
Jul 13, 12:48 PM EDTMesoscale DiscussionSPC87 min
Jul 13, 1:37 PM EDTSevere Thunderstorm WatchSPC10 hr
Jul 13, 4:07 PM EDTMesoscale DiscussionSPC113 min
Jul 13, 6:44 PM EDTMesoscale DiscussionSPC91 min
Jul 13, 8:16 PM EDTSpecial Weather StatementBUF44 min
Jul 14, 5:03 PM EDTSpecial Weather StatementBUF57 min
Jul 16, 2:41 PM EDTFlash Flood WatchBUF32 hr
Jul 17, 5:15 PM EDTAreal Flood WarningBUF3 hr
Jul 20, 3:05 PM EDTSevere Thunderstorm WatchSPC8 hr
Jul 20, 5:56 PM EDTSpecial Weather StatementBUF34 min
Jul 20, 7:24 PM EDTSpecial Weather StatementBUF36 min
Jul 20, 7:38 PM EDTSevere Thunderstorm WarningBUF31 min
Jul 20, 8:07 PM EDTAreal Flood WarningBUF81 min
Jul 27, 10:33 AM EDTMesoscale DiscussionSPC117 min
Jul 27, 11:12 AM EDTSevere Thunderstorm WatchSPC7 hr
Jul 27, 2:01 PM EDTMesoscale DiscussionSPC89 min
Aug 1, 5:14 PM EDTSpecial Weather StatementBUF46 min
Aug 9, 1:31 PM EDTHeat AdvisoryBUF54 hr
Aug 11, 7:46 AM EDTSevere Thunderstorm WarningBUF50 min
Aug 11, 7:55 AM EDTSevere Thunderstorm WarningBUF50 min
Aug 11, 10:15 PM EDTHeat AdvisoryBUF21 hr
Aug 17, 2:59 PM EDTFlash Flood WatchBUF41 hr
Aug 17, 4:17 PM EDTFlash Flood WarningBUF86 min
Aug 19, 12:21 AM EDTAreal Flood WarningBUF6 hr
Aug 24, 1:01 PM EDTHeat AdvisoryBUF54 hr
Aug 29, 2:04 PM EDTSpecial Weather StatementBUF41 min
Aug 29, 2:11 PM EDTSevere Thunderstorm WarningBUF64 min
Aug 29, 2:30 PM EDTSpecial Weather StatementBUF60 min
Aug 29, 3:25 PM EDTSevere Thunderstorm WarningBUF20 min
Aug 29, 3:38 PM EDTSevere Thunderstorm WarningBUF10 min
Aug 29, 5:29 PM EDTSpecial Weather StatementBUF31 min
Sep 12, 10:25 PM EDTSevere Thunderstorm WatchSPC4 hr
Sep 13, 12:26 AM EDTMesoscale DiscussionSPC94 min
Sep 13, 12:50 AM EDTSevere Thunderstorm WarningBUF55 min
Sep 13, 1:09 AM EDTSpecial Weather StatementBUF66 min
Oct 26, 5:05 PM EDTAreal Flood WarningBUF15 hr
Oct 26, 6:36 PM EDTAreal Flood WarningBUF4 hr
Oct 27, 7:27 AM EDTRiver Flood WarningBUF18 hr
Oct 29, 10:07 PM EDTAreal Flood WarningBUF41 hr
Oct 30, 8:35 AM EDTRiver Flood WarningBUF18 hr
Nov 22, 2:25 AM ESTSpecial Weather StatementBUF95 min
Dec 5, 3:33 AM ESTHigh Wind WarningBUF45 hr
Dec 5, 3:33 AM ESTWind AdvisoryBUF45 hr
Dec 10, 3:32 AM ESTHigh Wind WatchBUF9 hr
Dec 10, 3:32 AM ESTHigh Wind WarningBUF45 hr
Dec 17, 1:53 PM ESTWinter Weather AdvisoryBUF32 hr
Dec 18, 10:52 AM ESTMesoscale DiscussionSPC3 hr
Dec 22, 6:55 PM ESTWinter Weather AdvisoryBUF12 hr
Dec 27, 3:49 AM ESTWinter Weather AdvisoryBUF27 hr

By product

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

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20202022

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.