Alert archive / Idaho / Special Weather Statements in 2021

Special Weather Statement, NWS Missoula, MT

August 5, 2021Clearwater County, Idaho

NWS Missoula, MT issued this special weather statement at Aug 5, 2021, 8:24 PM PDT for Clearwater County, Idaho. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 5, 2021, 8:24 PM PDT (03:24 UTC)
Expired
Aug 5, 2021, 9:00 PM PDT
In force
36 min
Issued by
NWS Missoula, MT
Hail
0.00 in
Wind
40

County Clearwater County, ID

The radar

The Spokane radar (KOTX), 164 km from the middle of the area, began a volume at 03:27 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 00:00Z, 3.4 hours before the alert went out and 125 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 00:00Z on 2021-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2021-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -14 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
2910 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
-14 m²/s²
0-3 km storm-relative helicity
15 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

482 
WWUS85 KMSO 060324
SPSMSO

Special Weather Statement
National Weather Service Missoula MT
824 PM PDT Thu Aug 5 2021
 
IDZ005-007-060400-
Northern Clearwater Mountains ID-Orofino/Grangeville Region ID-
824 PM PDT Thu Aug 5 2021

...Strong thunderstorms will impact portions of north central Idaho
and western Clearwater Counties through 900 PM PDT...

At 823 PM PDT, Doppler radar was tracking strong thunderstorms along
a line extending from 10 miles northwest of Orofino to 7 miles south
of Elk River to near Headquarters to near Pierce. Movement was 
northeast at 35 mph. These storms have had a history of producing 
gusty outflow winds of 40-50 mph.

HAZARD...Winds in excess of 40 mph.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects.

Locations impacted include...
Orofino, Weippe, Elk River, Headquarters, Cardiff, Ahsahka, Jaype,
Dent, Teakean, Woodland and Riverside.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 4663 11645 4664 11633 4693 11633 4693 11551
      4688 11548 4625 11605 4626 11607 4642 11615
      4648 11637 4650 11638 4650 11645
TIME...MOT...LOC 0323Z 211DEG 31KT 4660 11642 4667 11618 4660 11591
4648 11585

MAX HAIL SIZE...0.00 IN
MAX WIND GUST...40 MPH

$$

The office that day

Everything else NWS Missoula, MT issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 5, 5:21 PM PDTSpecial Weather StatementMSOPowell39 min
Aug 5, 7:08 PM PDTSpecial Weather StatementMSO52 min
Aug 5, 8:12 PM PDTSpecial Weather StatementMSO48 min
Aug 6, 12:13 AM PDTSpecial Weather StatementMSORavalli47 min
Aug 6, 1:46 PM PDTFire Weather WatchMSOBeaverhead, Deer Lodge, Granite, Jefferson, Madison, Powell and 1 more22 hr
Aug 5, 8:20 PM PDTSpecial Weather StatementMSOIdaho40 min
Aug 5, 8:38 PM PDTSpecial Weather StatementMSOIdaho52 min
Aug 6, 4:32 PM PDTSpecial Weather StatementMSOLemhi43 min

Nearby

Special Weather Statements in Idaho, 2021Every special weather statement 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.