Alert archive / Montana / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 846
The Storm Prediction Center issued this severe thunderstorm watch at Aug 6, 2003, 1:10 PM PDT for Idaho County, Idaho; 18 counties in Montana. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 6, 2003, 1:10 PM PDT (20:10 UTC)
- Expired
- Aug 6, 2003, 8:00 PM PDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
Counties Idaho County, ID, Beaverhead County, MT, Cascade County, MT, Deer Lodge County, MT, Flathead County, MT, Glacier County, MT, Granite County, MT, Hill County, MT, Jefferson County, MT, Lake County, MT, Lewis and Clark County, MT, Liberty County, MT, Missoula County, MT, Pondera County, MT, Powell County, MT, Ravalli County, MT, Silver Bow County, MT, Teton County, MT, Toole County, MT
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 6, 2:45 PM PDT | Severe Thunderstorm Warning | MSO | Ravalli | 60 min |
| Aug 6, 2:49 PM PDT | Severe Thunderstorm Warning | MSO | Powell | 26 min |
| Aug 6, 3:23 PM PDT | Severe Thunderstorm Warning | MSO | Powell | 52 min |
| Aug 6, 3:27 PM PDT | Severe Thunderstorm Warning | MSO | Granite | 48 min |
| Aug 6, 3:45 PM PDT | Severe Thunderstorm Warning | TFX | Lewis and Clark | 45 min |
| Aug 6, 4:44 PM PDT | Severe Thunderstorm Warning | TFX | Lewis and Clark | 46 min |
| Aug 6, 5:03 PM PDT | Severe Thunderstorm Warning | MSO | Powell | 42 min |
| Aug 6, 5:10 PM PDT | Severe Thunderstorm Warning | TFX | Cascade | 50 min |
| Aug 6, 6:13 PM PDT | Severe Thunderstorm Warning | TFX | Lewis and Clark | 47 min |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Spokane, WA (KOTX), launched 12:00Z, 8.2 hours before the alert went out and 233 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2065 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- -23 m²/s²
- 0-3 km storm-relative helicity
- 59 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 6, 12:10 PM PDT | Mesoscale Discussion | SPC | Clearwater, Idaho, Lemhi | 3 hr |
| Aug 6, 4:41 PM PDT | Mesoscale Discussion | SPC | Idaho | 2 hr |
| Aug 6, 3:27 PM PDT | Mesoscale Discussion | SPC | Blaine, Daniels, Dawson, Garfield, McCone, Phillips and 4 more | 2 hr |
| Aug 6, 3:50 PM PDT | Severe Thunderstorm Watch | SPC | Blaine, Broadwater, Fergus, Golden Valley, Judith Basin, Meagher and 4 more | 5 hr |
Nearby
Severe Thunderstorm Watches in Montana, 2003Severe Thunderstorm Watches in Idaho, 2003Every severe thunderstorm watch in 2003
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.