Note:
The expiration time in the watch graphic is amended if the watch is
replaced, cancelled or extended.
Note: Click for
Watch Status Reports.
SEL3
URGENT - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Watch Number 313
NWS Storm Prediction Center Norman OK
140 PM MDT Sun Jun 28 2020
The NWS Storm Prediction Center has issued a
* Severe Thunderstorm Watch for portions of
Extreme southeastern Montana
Western South Dakota
Northeastern Wyoming
* Effective this Sunday afternoon and evening from 140 PM until
900 PM MDT.
* Primary threats include...
Scattered damaging wind gusts to 70 mph possible
Isolated large hail events to 1.5 inches in diameter possible
SUMMARY...Thunderstorms are expected to increase in
coverage/intensity while spreading northeastward from northeastern
Wyoming this afternoon. The storms will evolve into a mix of
clusters/line segments with an accompanying threat for damaging
winds and isolated large hail through this evening.
The severe thunderstorm watch area is approximately along and 75
statute miles east and west of a line from 35 miles northwest of
Buffalo SD to 75 miles southeast of Gillette WY. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU3).
PRECAUTIONARY/PREPAREDNESS ACTIONS...
REMEMBER...A Severe Thunderstorm Watch means conditions are
favorable for severe thunderstorms in and close to the watch area.
Persons in these areas should be on the lookout for threatening
weather conditions and listen for later statements and possible
warnings. Severe thunderstorms can and occasionally do produce
tornadoes.
&&
OTHER WATCH INFORMATION...CONTINUE...WW 312...
AVIATION...A few severe thunderstorms with hail surface and aloft to
1.5 inches. Extreme turbulence and surface wind gusts to 60 knots. A
few cumulonimbi with maximum tops to 500. Mean storm motion vector
23035.
...Thompson
Note:
The Aviation Watch (SAW) product is an approximation to the watch area.
The actual watch is depicted by the shaded areas.
SAW3
WW 313 SEVERE TSTM MT SD WY 281940Z - 290300Z
AXIS..75 STATUTE MILES EAST AND WEST OF LINE..
35NW 2WX/BUFFALO SD/ - 75SE GCC/GILLETTE WY/
..AVIATION COORDS.. 65NM E/W /77SW DIK - 68WSW RAP/
HAIL SURFACE AND ALOFT..1.5 INCHES. WIND GUSTS..60 KNOTS.
MAX TOPS TO 500. MEAN STORM MOTION VECTOR 23035.
LAT...LON 45920247 43570297 43570597 45920560
THIS IS AN APPROXIMATION TO THE WATCH AREA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE WOUS64 KWNS
FOR WOU3.
Watch 313 Status Report Messages:
STATUS REPORT #2 ON WW 313
VALID 290130Z - 290240Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 60 SW RAP TO
60 SSW 2WX TO 45 SSW Y22.
..SPC..06/29/20
ATTN...WFO...BYZ...UNR...
&&
STATUS REPORT FOR WS 313
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
SDC019-033-081-093-103-105-137-290240-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BUTTE CUSTER LAWRENCE
MEADE PENNINGTON PERKINS
ZIEBACH
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
STATUS REPORT #1 ON WW 313
VALID 282225Z - 282340Z
SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 65 NNE DGW
TO 35 SSW BHK.
..SPC..06/28/20
ATTN...WFO...BYZ...UNR...
&&
STATUS REPORT FOR WS 313
SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS
MTC011-282340-
MT
. MONTANA COUNTIES INCLUDED ARE
CARTER
$$
SDC019-033-063-081-093-103-105-282340-
SD
. SOUTH DAKOTA COUNTIES INCLUDED ARE
BUTTE CUSTER HARDING
LAWRENCE MEADE PENNINGTON
PERKINS
$$
WYC011-045-282340-
WY
. WYOMING COUNTIES INCLUDED ARE
CROOK WESTON
$$
THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE
REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL
INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES
CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES.
$$
Note:
Click for Complete Product Text.
Tornadoes
Probability of 2 or more tornadoes
|
Low (10%)
|
Probability of 1 or more strong (EF2-EF5) tornadoes
|
Low (<2%)
|
Wind
Probability of 10 or more severe wind events
|
Mod (40%)
|
Probability of 1 or more wind events > 65 knots
|
Low (20%)
|
Hail
Probability of 10 or more severe hail events
|
Mod (30%)
|
Probability of 1 or more hailstones > 2 inches
|
Low (20%)
|
Combined Severe Hail/Wind
Probability of 6 or more combined severe hail/wind events
|
High (70%)
|
For each watch, probabilities for particular events inside the watch
(listed above in each table) are determined by the issuing forecaster.
The "Low" category contains probability values ranging from less than 2%
to 20% (EF2-EF5 tornadoes), less than 5% to 20% (all other probabilities),
"Moderate" from 30% to 60%, and "High" from 70% to greater than 95%.
High values are bolded and lighter in color to provide awareness of
an increased threat for a particular event.
weather.gov 
@NWSSPC
