Alert archive / Washington / Lewis County

Weather alerts in Lewis County, Washington, 2018

5 weather alerts in 2018, from the National Weather Service and the Storm Prediction Center. An alert counts here when it covered this county.

Lewis County and its neighbors

Each county as a circle sized by its count in 2018. Tap one for its archive.

Alerts
5
Warnings
2
Watches
3
Advisories
0
Busiest month
February1 alerts
Busiest day
February 2, 20181 alerts

Over time

By month

Warning verification

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

Lewis County, 2018

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

Each office's whole area, 2018

WarningsWith a reportFalse alarm ratioReportsInside a warningMean lead time
NWS Seattle, WA: tornado warnings030%
NWS Seattle, WA: severe thunderstorm warnings020%
NWS Seattle, WA: flash flood warnings020%
NWS Portland, OR: tornado warnings10100%50%
NWS Portland, OR: severe thunderstorm warnings80100%40%
NWS Portland, OR: flash flood warnings010%
NWS Spokane, WA: severe thunderstorm warnings8363%1520%12 min
NWS Spokane, WA: flash flood warnings0160%
NWS Pendleton, OR: severe thunderstorm warnings6350%850%7 min
NWS Pendleton, OR: flash flood warnings220%1932%73 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
Feb 2, 1:49 PM PSTFlood WatchSEW62 hr
Apr 13, 9:43 PM PDTFlood WatchSEW29 hr
Jul 28, 2:38 PM PDTRed Flag WarningSEW56 hr
Aug 6, 2:57 PM PDTRed Flag WarningSEW3 days
Dec 17, 2:35 PM PSTFlood WatchSEW21 hr

By product

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

ProductAlerts
Flooding
Flood Watch3
Fire
Red Flag Warning2

The busiest days

Days with the most alerts issued, by UTC date.

Nearby

Alerts in force nowTornadoes on recordForecastThe radar archive20172019

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.