Flash Flood Warning 5, NWS Boise, ID

Issued

Jul 31, 2021, 11:58 PM MDT (05:58 UTC)

Expired

Aug 1, 2021, 2:00 AM MDT

In force

2 hr

Issued by

NWS Boise, ID

Area

Storm-based polygon

Flood severity

None

Counties Canyon County, ID, Gem County, ID, Owyhee County, ID, Payette County, ID

The Boise radar (KCBX), 49 km from the middle of the area, began a volume at 06:03 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.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

466 
WGUS55 KBOI 010558
FFWBOI
IDC027-045-073-075-010800-
/O.NEW.KBOI.FF.W.0005.210801T0558Z-210801T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Boise ID
1158 PM MDT Sat Jul 31 2021

The National Weather Service in Boise has issued a

* Flash Flood Warning for...
  Canyon County in southwestern Idaho...
  Southwestern Gem County in southwestern Idaho...
  Northwestern Owyhee County in southwestern Idaho...
  Southwestern Payette County in southwestern Idaho...

* Until 200 AM MDT.

* At 1158 PM MDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  1 and 1.5 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar and automated gauges.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Nampa, Caldwell, Parma, Star, Middleton, Nyssa, Homedale, New 
  Plymouth, Wilder, Marsing, Greenleaf, Notus, Sand Hollow, Huston, 
  Lake Lowell, Letha and Givens Hot Springs.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

Be aware of your surroundings and do not drive on flooded roads.

Please report observed flooding to local emergency services or law 
enforcement and request they pass this information to the National 
Weather Service when you can do so safely.

&&

LAT...LON 4400 11690 4402 11668 4388 11654 4376 11651
      4363 11651 4363 11649 4351 11647 4339 11680
      4377 11703 4381 11703

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

ST

507 
WGUS75 KBOI 010756
FFSBOI

Flash Flood Statement
National Weather Service Boise ID
156 AM MDT Sun Aug 1 2021

IDC027-045-073-075-010806-
/O.EXP.KBOI.FF.W.0005.000000T0000Z-210801T0800Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Canyon ID-Gem ID-Owyhee ID-Payette ID-
156 AM MDT Sun Aug 1 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 2 AM MDT EARLY THIS MORNING 
FOR CANYON, SOUTHWESTERN GEM, NORTHWESTERN OWYHEE AND SOUTHWESTERN 
PAYETTE COUNTIES...

The heavy rain has ended. Flooding is no longer expected to pose a 
threat. However, areas of ponding of water on roadways may persist. 
Please continue to heed remaining road closures.

LAT...LON 4400 11690 4402 11668 4388 11654 4376 11651
      4363 11651 4363 11649 4351 11647 4339 11680
      4377 11703 4381 11703

$$

ST

Flash Flood Warnings in Idaho, 2021Every flash flood warning in 2021

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