Alert archive / Washington / Flash Flood Watches in 2021

Flash Flood Watch 4, NWS Spokane, WA

August 16, 2021Ferry County, Pend Oreille County, Stevens County, Washington; Bonner County, Boundary County, Idaho

NWS Spokane, WA issued this flash flood watch at Aug 16, 2021, 2:29 PM PDT for Ferry County, Pend Oreille County, Stevens County, Washington; Bonner County, Boundary County, Idaho. It took effect at Aug 17, 2021, 10:00 AM PDT. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Aug 16, 2021, 2:29 PM PDT (21:29 UTC)
In effect from
Aug 17, 2021, 10:00 AM PDT
Expired
Aug 17, 2021, 9:00 PM PDT
In force
11 hr
Issued by
NWS Spokane, WA
Flood severity
None

Counties Bonner County, ID, Boundary County, ID, Ferry County, WA, Pend Oreille County, WA, Stevens County, WA

The radar

The Spokane radar (KOTX), 93 km from the middle of the area, began a volume at 21:29 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, 9.5 hours before the alert went out and 113 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 2021-08-16Temperature 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 2021-08-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -20 square meters per square second.193958Sfc1 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
3445 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-20 m²/s²
0-3 km storm-relative helicity
44 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

514 
WGUS66 KOTX 162129
FFAOTX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Spokane WA
229 PM PDT Mon Aug 16 2021

IDC017-021-WAC051-065-171500-
/O.NEW.KOTX.FF.A.0004.210817T1700Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bonner-Boundary-Pend Oreille-Stevens-
Including the cities of Porthill, Eastport, Sandpoint, Clark
Fork, Diamond Lake, Colville, Blanchard, Northport, Bonners
Ferry, Metaline Falls, Chewelah, Cusick, Moyie Springs,
Careywood, Ione, Newport, Kettle Falls, Springdale, Naples, and
Priest River
229 PM PDT Mon Aug 16 2021

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH TUESDAY 
EVENING...

The National Weather Service in Spokane has issued a

* Flash Flood Watch for Portions of North Idaho, including the 
  following areas, Bonner and Boundary. Portions of Northeast 
  Washington, including the following areas, Pend Oreille and 
  Stevens.

* From Tuesday morning through Tuesday evening.

* Slow moving thunderstorms will be capable of producing locally 
  heavy rainfall over parts of the far north Idaho Panhandle and the 
  mountainous terrain of far northeast Washington.

* Locally heavy rain over steep terrain and recently burned areas 
  heighten the risk of flash flooding and debris flows.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

GKOCH
2 follow-up statements
998 
WGUS66 KOTX 171344
FFAOTX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Spokane WA
644 AM PDT Tue Aug 17 2021

WAC019-180400-
/O.EXA.KOTX.FF.A.0004.210817T1700Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Ferry-
Including the cities of Laurier, Keller, Curlew, Republic,
Danville, and Inchelium
644 AM PDT Tue Aug 17 2021

...FLASH FLOOD WATCH IN EFFECT FROM 10 AM PDT THIS MORNING THROUGH 
THIS EVENING...

The National Weather Service in Spokane has expanded the

* Flash Flood Watch to include A portion of Northeast Washington, 
  including the following area, Ferry.

* From 10 AM PDT this morning through this evening.

* Slow moving thunderstorms will be capable of producing locally 
  heavy rainfall over parts of the far north Idaho Panhandle and the 
  mountainous terrain of far northeast Washington.

* Locally heavy rain over steep terrain and recently burned areas 
  heighten the risk of flash flooding and debris flows.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

IDC017-021-WAC051-065-180400-
/O.CON.KOTX.FF.A.0004.210817T1700Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bonner-Boundary-Pend Oreille-Stevens-
Including the cities of Porthill, Eastport, Sandpoint, Clark
Fork, Diamond Lake, Colville, Blanchard, Northport, Bonners
Ferry, Metaline Falls, Chewelah, Cusick, Moyie Springs,
Careywood, Ione, Newport, Kettle Falls, Springdale, Naples, and
Priest River
644 AM PDT Tue Aug 17 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM 10 AM PDT THIS MORNING 
THROUGH THIS EVENING...

The Flash Flood Watch continues for

* Portions of North Idaho, including the following areas, Bonner and 
  Boundary. Portions of Northeast Washington, including the 
  following areas, Pend Oreille and Stevens.

* From 10 AM PDT this morning through this evening.

* Slow moving thunderstorms will be capable of producing locally 
  heavy rainfall over parts of the far north Idaho Panhandle and the 
  mountainous terrain of far northeast Washington.

* Locally heavy rain over steep terrain and recently burned areas 
  heighten the risk of flash flooding and debris flows.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

$$

SB
618 
WGUS66 KOTX 180354
FFAOTX

Flood Watch
National Weather Service Spokane WA
854 PM PDT Tue Aug 17 2021

IDC017-021-WAC019-051-065-180500-
/O.EXP.KOTX.FF.A.0004.000000T0000Z-210818T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Bonner-Boundary-Ferry-Pend Oreille-Stevens-
Including the cities of Porthill, Laurier, Chewelah, Blanchard,
Republic, Danville, Naples, Eastport, Cusick, Colville,
Northport, Bonners Ferry, Springdale, Kettle Falls, Sandpoint,
Clark Fork, Diamond Lake, Ione, Newport, Priest River, Curlew,
Careywood, Keller, Moyie Springs, Metaline Falls, and Inchelium
854 PM PDT Tue Aug 17 2021

...FLASH FLOOD WATCH WILL EXPIRE AT 9 PM PDT THIS EVENING...

The Flash Flood Watch for Portions of North Idaho, including the 
following areas, Bonner and Boundary. Portions of Northeast 
Washington, including the following areas, Ferry, Pend Oreille and 
Stevens. will expire at 9 PM PDT this evening.

Flooding is no longer expected to pose a threat.

$$

SVH

Nearby

Flash Flood Watches in Washington, 2021Flash Flood Watches in Idaho, 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.