Alert archive / Idaho / Severe Thunderstorm Warnings in 2020
Severe Thunderstorm Warning 35, NWS Boise, ID
NWS Boise, ID issued this severe thunderstorm warning at Aug 17, 2020, 6:51 PM MDT for Adams County, Valley County, Washington County, Idaho; Baker County, Oregon. It was in force for 39 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Aug 17, 2020, 6:51 PM MDT (00:51 UTC)
- Expired
- Aug 17, 2020, 7:30 PM MDT
- In force
- 39 min
- Issued by
- NWS Boise, ID
- Area
- Storm-based polygon
- Hail
- 0.75 in
- Wind
- 60.0 mph
Counties Adams County, ID, Valley County, ID, Washington County, ID, Baker County, OR
The radar
The Boise radar (KCBX), 138 km from the middle of the area, began a volume at 00:56 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 watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Aug 17, 4:19 PM MDT | Severe Thunderstorm Watch | SPC | 7 hr |
The nearest sounding before it
Boise Airport, ID (KBOI), launched 00:00Z, 0.9 hours before the alert went out and 131 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.
- Mixed-layer CAPE
- 701 J/kg
- Mixed-layer CIN
- -128 J/kg
- Mixed-layer LCL
- 3285 m above ground
- 0-6 km bulk shear
- 26 kt
- 0-1 km storm-relative helicity
- -28 m²/s²
- 0-3 km storm-relative helicity
- 27 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.1
The office that day
Everything else NWS Boise, ID issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 17, 7:20 PM MDT | Severe Thunderstorm Warning | BOI | Adams, Valley | 25 min |
| Aug 18, 12:58 PM MDT | Red Flag Warning | BOI | Idaho, Owyhee, Valley | 34 hr |
| Aug 18, 5:00 PM MDT | Special Weather Statement | BOI | 45 min | |
| Aug 18, 5:25 PM MDT | Special Weather Statement | BOI | Twin Falls | 50 min |
| Aug 18, 5:55 PM MDT | Special Weather Statement | BOI | Owyhee | 50 min |
| Aug 18, 3:52 PM MDT | Special Weather Statement | BOI | Harney | 38 min |
| Aug 18, 4:31 PM MDT | Severe Thunderstorm Warning | BOI | Harney, Malheur | 44 min |
| Aug 18, 5:16 PM MDT | Special Weather Statement | BOI | Malheur | 44 min |
| Aug 18, 5:34 PM MDT | Severe Thunderstorm Warning | BOI | Malheur | 41 min |
| Aug 18, 5:44 PM MDT | Special Weather Statement | BOI | Malheur | 46 min |
Nearby
Severe Thunderstorm Warnings in Idaho, 2020Severe Thunderstorm Warnings in Oregon, 2020Every severe thunderstorm warning in 2020
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.