Alert archive / Idaho / Flash Flood Watches in 2021

Flash Flood Watch 5, NWS Spokane, WA

August 19, 20218 counties in Idaho; 8 counties in Washington

NWS Spokane, WA issued this flash flood watch at Aug 19, 2021, 1:01 PM PDT for 8 counties in Idaho; 8 counties in Washington. It took effect at Aug 20, 2021, 1:00 PM PDT. It was in force for 27 hr.

The area

The counties it named.

The facts

Issued
Aug 19, 2021, 1:01 PM PDT (20:01 UTC)
In effect from
Aug 20, 2021, 1:00 PM PDT
Expired
Aug 21, 2021, 4:00 PM PDT
In force
27 hr
Issued by
NWS Spokane, WA
Flood severity
None

Counties Benewah County, ID, Bonner County, ID, Boundary County, ID, Kootenai County, ID, Latah County, ID, Lewis County, ID, Nez Perce County, ID, Shoshone County, ID, Asotin County, WA, Chelan County, WA, Ferry County, WA, Garfield County, WA, Okanogan County, WA, Pend Oreille County, WA, Spokane County, WA, Stevens County, WA

The radar

The Spokane radar (KOTX), 23 km from the middle of the area, began a volume at 20:05 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Spokane, WA (KOTX), launched 12:00Z, 8.0 hours before the alert went out and 77 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Spokane, WA at 12:00Z on 2021-08-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Spokane, WA at 12:00Z on 2021-08-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 55 square meters per square second.1939587897Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1552 m above ground
0-6 km bulk shear
26 kt
0-1 km storm-relative helicity
55 m²/s²
0-3 km storm-relative helicity
179 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

996 
WGUS66 KOTX 192001
FFAOTX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Spokane WA
101 PM PDT Thu Aug 19 2021

.A strong system moving into the Pacific Northwest will bring 
scattered to numerous showers and thunderstorms to the area starting 
Friday afternoon and continuing through Saturday.

IDC009-017-021-055-057-079-WAC007-019-047-051-065-202015-
/O.NEW.KOTX.FF.A.0005.210820T2000Z-210821T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Benewah-Bonner-Boundary-Kootenai-Latah-Shoshone-Chelan-Ferry-
Okanogan-Pend Oreille-Stevens-
Including the cities of Porthill, Deary, Laurier, Chewelah,
Wallace, Osburn, Worley, Curlew, Methow, Springdale, Hayden,
Rathdrum, Republic, Danville, Juliaetta, Naples, Wenatchee,
Eastport, St Maries, Manson, Omak, Tensed, Cusick, Moscow,
Northport, Bonners Ferry, Athol, Kellogg, Calder, Cashmere,
Brewster, Plain, Okanogan, Colville, Mullan, Diamond Lake, Kettle
Falls, Newport, Smelterville, Sandpoint, Clark Fork, Coeur
d'Alene, Ione, Leavenworth, Oroville, Post Falls, Moyie Springs,
Mazama, Kendrick, Bayview, Conconully, Entiat, Priest River,
Potlatch, Winthrop, Plummer, Blanchard, Genesee, Twisp,
Careywood, Keller, Chelan, Inchelium, Metaline Falls, and
Pinehurst
101 PM PDT Thu Aug 19 2021

...FLASH FLOOD WATCH IN EFFECT FROM FRIDAY AFTERNOON THROUGH 
SATURDAY AFTERNOON...

The National Weather Service in Spokane has issued a

* Flash Flood Watch for Portions of North Idaho, including the 
  following areas, Benewah, Bonner, Boundary, Kootenai, Latah and 
  Shoshone. Portions of Washington, including the following areas, 
  Chelan, Ferry, Okanogan, Pend Oreille and Stevens.

* From Friday afternoon through Saturday afternoon.

* Scattered to numerous showers and thunderstorms will develop 
  Friday afternoon and continue through Saturday. These showers will 
  be slow moving and contain moderate to heavy rain.

* Locally heavy rain in a short amount of time over steep terrain or 
  recently burned areas heightens the risk of dangerous flash 
  flooding and debris flows. Sudden rushes of water in creeks and 
  stream drainages could wash away anyone or thing nearby. Debris 
  flows can cause considerable damage to structures in its way. Road 
  washouts or rockslides are also possible from the localized heavy 
  rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

LN
3 follow-up statements
676 
WGUS66 KOTX 201832
FFAOTX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Spokane WA
1132 AM PDT Fri Aug 20 2021

.A strong system moving into the Pacific Northwest will bring 
scattered to numerous showers and thunderstorms to the area starting 
this afternoon and continuing through Saturday.

IDC061-069-WAC003-023-063-211645-
/O.EXA.KOTX.FF.A.0005.210820T2000Z-210821T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Lewis-Nez Perce-Asotin-Garfield-Spokane-
Including the cities of Rockford, Peck, Clarkston, Pomeroy,
Winchester, Nezperce, Anatone, Craigmont, Cheney, Liberty Lake,
Gifford, Kamiah, Lapwai, Airway Heights, Medical Lake, Deer Park,
Culdesac, Spokane, Lewiston, and Asotin
1132 AM PDT Fri Aug 20 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH SATURDAY AFTERNOON...

The National Weather Service in Spokane has expanded the

* Flash Flood Watch to include Portions of North Central Idaho, 
  including the following areas, Lewis and Nez Perce. Portions of 
  Washington, including the following areas, Asotin, Garfield and 
  Spokane.

* Through Saturday afternoon.

* Scattered to numerous showers and thunderstorms will develop this 
  afternoon and continue through Saturday. These showers will be 
  slow moving and contain moderate to heavy rain.

* Locally heavy rain in a short amount of time over steep terrain or 
  recently burned areas heightens the risk of dangerous flash 
  flooding and debris flows. Sudden rushes of water in creeks and 
  stream drainages could wash away anyone or anything nearby. Debris 
  flows can cause considerable damage to structures along the way. 
  Road washouts or rockslides are also possible from localized heavy 
  rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

IDC009-017-021-055-057-079-WAC007-019-047-051-065-211645-
/O.CON.KOTX.FF.A.0005.210820T2000Z-210821T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Benewah-Bonner-Boundary-Kootenai-Latah-Shoshone-Chelan-Ferry-
Okanogan-Pend Oreille-Stevens-
Including the cities of Porthill, Deary, Laurier, Chewelah,
Wallace, Osburn, Worley, Curlew, Methow, Springdale, Hayden,
Rathdrum, Republic, Danville, Juliaetta, Naples, Wenatchee,
Eastport, St Maries, Manson, Omak, Tensed, Cusick, Moscow,
Northport, Bonners Ferry, Athol, Kellogg, Calder, Cashmere,
Brewster, Plain, Okanogan, Colville, Mullan, Diamond Lake, Kettle
Falls, Newport, Smelterville, Sandpoint, Clark Fork, Coeur
d'Alene, Ione, Leavenworth, Oroville, Post Falls, Moyie Springs,
Mazama, Kendrick, Bayview, Conconully, Entiat, Priest River,
Potlatch, Winthrop, Plummer, Blanchard, Genesee, Twisp,
Careywood, Keller, Chelan, Inchelium, Metaline Falls, and
Pinehurst
1132 AM PDT Fri Aug 20 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SATURDAY AFTERNOON...

The Flash Flood Watch continues for

* Portions of North Idaho, including the following areas, Benewah, 
  Bonner, Boundary, Kootenai, Latah and Shoshone. Portions of 
  Washington, including the following areas, Chelan, Ferry, 
  Okanogan, Pend Oreille and Stevens.

* Through Saturday afternoon.

* Scattered to numerous showers and thunderstorms will develop this 
  afternoon and continue through Saturday. These showers will be 
  slow moving and contain moderate to heavy rain.

* Locally heavy rain in a short amount of time over steep terrain or 
  recently burned areas heightens the risk of dangerous flash 
  flooding and debris flows. Sudden rushes of water in creeks and 
  stream drainages could wash away anyone or anything nearby. Debris 
  flows can cause considerable damage to structures along the way. 
  Road washouts or rockslides are also possible from localized heavy 
  rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

KD
947 
WGUS66 KOTX 211645
FFAOTX

Flood Watch
National Weather Service Spokane WA
945 AM PDT Sat Aug 21 2021

.A strong system moving into the Pacific Northwest will continue to 
bring scattered showers and isolated thunderstorms to the area 
through the afternoon.

IDC009-017-021-055-057-061-069-079-WAC003-007-019-023-047-051-063-
065-212300-
/O.CON.KOTX.FF.A.0005.000000T0000Z-210821T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Benewah-Bonner-Boundary-Kootenai-Latah-Lewis-Nez Perce-Shoshone-
Asotin-Chelan-Ferry-Garfield-Okanogan-Pend Oreille-Spokane-
Stevens-
Including the cities of Porthill, Rockford, Deary, Manson,
Chewelah, Winchester, Osburn, Worley, Curlew, Nezperce, Methow,
Springdale, Hayden, Liberty Lake, Rathdrum, Republic, Danville,
Cheney, Kamiah, Juliaetta, Naples, Wenatchee, Eastport, St
Maries, Wallace, Omak, Tensed, Cusick, Moscow, Ione, Northport,
Bonners Ferry, Diamond Lake, Athol, Kellogg, Calder, Cashmere,
Brewster, Plain, Okanogan, Peck, Mullan, Pomeroy, Kettle Falls,
Newport, Smelterville, Spokane, Sandpoint, Clark Fork, Coeur
d'Alene, Craigmont, Leavenworth, Deer Park, Colville, Oroville,
Post Falls, Moyie Springs, Mazama, Medical Lake, Kendrick,
Bayview, Lewiston, Conconully, Entiat, Priest River, Potlatch,
Winthrop, Clarkston, Plummer, Laurier, Anatone, Blanchard,
Lapwai, Gifford, Genesee, Airway Heights, Twisp, Careywood,
Keller, Culdesac, Chelan, Inchelium, Metaline Falls, Asotin, and
Pinehurst
945 AM PDT Sat Aug 21 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 4 PM PDT THIS 
AFTERNOON...

The Flash Flood Watch continues for

* Portions of Idaho, including the following areas, Benewah, Bonner, 
  Boundary, Kootenai, Latah, Lewis, Nez Perce and Shoshone. Portions 
  of Washington, including the following areas, Asotin, Chelan, 
  Ferry, Garfield, Okanogan, Pend Oreille, Spokane and Stevens.

* Until 4 PM PDT this afternoon.

* Scattered to numerous showers and will continue to develop through 
  the afternoon. These showers will be slow moving and contain 
  moderate to heavy rain. There is a chance for isolated 
  thunderstorms in northern Idaho and northern Washington.

* Locally heavy rain in a short amount of time over steep terrain or 
  recently burned areas heightens the risk of dangerous flash 
  flooding and debris flows. Sudden rushes of water in creeks and 
  stream drainages could wash away anyone or anything nearby. Debris 
  flows can cause considerable damage to structures along the way. 
  Road washouts or rockslides are also possible from localized heavy 
  rain.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be prepared to take action 
should Flash Flood Warnings be issued.

&&

$$

JS
497 
WGUS66 KOTX 212254
FFAOTX

Flood Watch
National Weather Service Spokane WA
354 PM PDT Sat Aug 21 2021

IDC009-017-021-055-057-061-069-079-WAC003-007-019-023-047-051-063-
065-220000-
/O.EXP.KOTX.FF.A.0005.000000T0000Z-210821T2300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Benewah-Bonner-Boundary-Kootenai-Latah-Lewis-Nez Perce-Shoshone-
Asotin-Chelan-Ferry-Garfield-Okanogan-Pend Oreille-Spokane-
Stevens-
Including the cities of Porthill, Rockford, Deary, Manson,
Chewelah, Winchester, Osburn, Worley, Curlew, Nezperce, Methow,
Springdale, Hayden, Liberty Lake, Rathdrum, Republic, Danville,
Cheney, Kamiah, Juliaetta, Naples, Wenatchee, Eastport, St
Maries, Wallace, Omak, Tensed, Cusick, Moscow, Ione, Northport,
Bonners Ferry, Diamond Lake, Athol, Kellogg, Calder, Cashmere,
Brewster, Plain, Okanogan, Peck, Mullan, Pomeroy, Kettle Falls,
Newport, Smelterville, Spokane, Sandpoint, Clark Fork, Coeur
d'Alene, Craigmont, Leavenworth, Deer Park, Colville, Oroville,
Post Falls, Moyie Springs, Mazama, Medical Lake, Kendrick,
Bayview, Lewiston, Conconully, Entiat, Priest River, Potlatch,
Winthrop, Clarkston, Plummer, Laurier, Anatone, Blanchard,
Lapwai, Gifford, Genesee, Airway Heights, Twisp, Careywood,
Keller, Culdesac, Chelan, Inchelium, Metaline Falls, Asotin, and
Pinehurst
354 PM PDT Sat Aug 21 2021

...FLASH FLOOD WATCH WILL EXPIRE AT 4 PM PDT THIS AFTERNOON...

The Flash Flood Watch for Portions of Idaho, including the following 
areas, Benewah, Bonner, Boundary, Kootenai, Latah, Lewis, Nez Perce 
and Shoshone. Portions of Washington, including the following areas, 
Asotin, Chelan, Ferry, Garfield, Okanogan, Pend Oreille, Spokane and 
Stevens. will expire at 4 PM PDT this afternoon.

The Flood Watch is cancelled. Flooding is no longer expected to pose 
a threat. Please continue to heed remaining road closures.

$$

JCLEV

Nearby

Flash Flood Watches in Idaho, 2021Flash Flood Watches in Washington, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.