Alert archive / Washington / Chelan County

Weather alerts in Chelan County, Washington, 2011

30 weather alerts in 2011, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Chelan County and its neighbors

Each county as a circle sized by its count in 2011. Tap one for its archive.

Alerts
30
Warnings
5
Watches
7
Advisories
17
Busiest month
January8 alerts
Busiest day
January 10, 20112 alerts

Over time

By month

Warning verification

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

Chelan County, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
Tornado warnings00
Severe thunderstorm warnings00
Flash flood warnings010%

Each office's whole area, 2011

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Seattle, WA: tornado warnings020%
NWS Seattle, WA: severe thunderstorm warnings20100%10%
NWS Portland, OR: severe thunderstorm warnings10280%667%15 min
NWS Spokane, WA: tornado warnings010%
NWS Spokane, WA: severe thunderstorm warnings3233%650%8 min
NWS Spokane, WA: flash flood warnings20100%20%
NWS Pendleton, OR: tornado warnings010%
NWS Pendleton, OR: severe thunderstorm warnings12558%1155%21 min
NWS Pendleton, OR: flash flood warnings5340%4100%84 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, Pacific Time. Each opens its own page with the text, the map, the radar and the sounding.

IssuedProductOfficeLasted
Jan 3, 3:08 PM PSTAir Stagnation AdvisoryOTX4 days
Jan 7, 1:30 AM PSTWinter Weather AdvisoryOTX10 hr
Jan 10, 2:38 AM PSTWinter Storm WatchOTX32 hr
Jan 10, 1:55 PM PSTWinter Storm WarningOTX3 days
Jan 14, 3:46 PM PSTFlood WatchOTX68 hr
Jan 15, 7:46 PM PSTAreal Flood AdvisoryOTX40 hr
Jan 16, 3:44 AM PSTWind AdvisoryOTX39 hr
Jan 21, 4:38 AM PSTWind AdvisoryOTX15 hr
Feb 6, 3:52 AM PSTWind AdvisoryOTX35 hr
Feb 21, 3:03 PM PSTWinter Storm WarningOTX4 days
Feb 21, 3:03 PM PSTWinter Weather AdvisoryOTX4 days
Feb 27, 5:02 PM PSTMesoscale DiscussionSPC6 hr
Mar 29, 3:17 PM PDTWind AdvisoryOTX53 hr
Mar 31, 8:50 AM PDTAreal Flood AdvisoryOTX11 hr
Apr 1, 2:00 PM PDTAreal Flood AdvisoryOTX22 hr
Apr 3, 12:08 PM PDTFlood WatchOTX24 hr
Apr 4, 12:24 PM PDTAreal Flood AdvisoryOTX23 hr
May 12, 4:21 PM PDTFlood WatchOTX23 hr
May 13, 1:47 PM PDTRiver Flood WatchOTX4 days
May 13, 3:28 PM PDTAreal Flood WarningOTX4 days
May 14, 11:48 AM PDTRiver Flood WarningOTX16 hr
Jun 3, 1:21 PM PDTFlood WatchOTX4 days
Jun 7, 11:25 AM PDTFlood WatchOTX4 days
Jun 10, 4:08 PM PDTAreal Flood AdvisoryOTX2 hr
Nov 13, 8:19 AM PSTWind AdvisoryOTX11 hr
Nov 15, 3:19 PM PSTWinter Weather AdvisoryOTX37 hr
Dec 1, 10:26 AM PSTAir Stagnation AdvisoryOTX19 days
Dec 27, 11:00 PM PSTWinter Storm WarningOTX7 hr
Dec 29, 4:19 AM PSTWinter Weather AdvisoryOTX39 hr
Dec 30, 9:42 PM PSTWind AdvisoryOTX6 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 archive20102012

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.