Alert archive / Wyoming / Severe Thunderstorm Warnings in 2015

Severe Thunderstorm Warning 125, NWS Cheyenne, WY

June 25, 2015Laramie County, Wyoming

NWS Cheyenne, WY issued this severe thunderstorm warning at Jun 25, 2015, 7:42 PM MDT for Laramie County, Wyoming. It was in force for 48 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: Jun 25, 2015, 7:42 PM MDT (01:42 UTC)
Expired: Jun 25, 2015, 8:30 PM MDT
In force: 48 min
Issued by: NWS Cheyenne, WY
Area: Storm-based polygon
Hail: 1.5 in
Wind: 60.0 mph

County Laramie County, WY

The radar

The Cheyenne radar (KCYS), 20 km from the middle of the area, began a volume at 01:44 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
Jun 25, 2:30 PM MDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Denver, CO (KDEN), launched 00:00Z, 1.7 hours before the alert went out and 202 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 878 J/kg
Mixed-layer CIN: -106 J/kg
Mixed-layer LCL: 2352 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 75 m²/s²
0-3 km storm-relative helicity: 169 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Cheyenne, WY wrote its last area forecast discussion before this severe thunderstorm warning went out at Jun 25, 7:30 PM MDT, 12 minutes earlier.

Area forecast discussion, Jun 25, 7:30 PM MDT, 12 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Hazardous weather outlook, Jun 25, 6:58 PM MDT, 44 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHEYENNE WY
658 PM MDT THU JUN 25 2015

NEZ002-003-019>021-054-055-095-096-270100-
DAWES-BOX BUTTE-SCOTTS BLUFF-BANNER-MORRILL-KIMBALL-CHEYENNE-
NORTH SIOUX-SOUTH SIOUX-
658 PM MDT THU JUN 25 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF WESTERN
NEBRASKA.

.DAY ONE...TONIGHT

SCATTERED THUNDERSTORMS ARE STILL LIKELY IN THE NEBRASKA PANHANDLE
TONIGHT. A FEW OF THESE STORMS WILL BE CAPABLE OF PRODUCING
GOLFBALL SIZED HAIL...DOWNBURST WINDS TO 60 MPH AND HEAVY RAINFALL
LEADING TO FLASH FLOODING. AREAS OF CONCERN TONIGHT WILL BE THE
SOUTHERN PANHANDLE...ROUGHLY SOUTH OF A LINE FROM ALLIANCE TO
TORRINGTON THROUGH 10 PM THIS EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED MAINLY LATE DAY THUNDERSTORMS ARE POSSIBLE FRIDAY AND
AGAIN ON TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL BE NEEDED THROUGH 10 PM SOUTH OF A LINE
FROM ALLIANCE TO TORRINGTON.

WYZ101>103-105>108-110-114>119-270100-
CONVERSE COUNTY LOWER ELEVATIONS-NIOBRARA COUNTY-
NORTH LARAMIE RANGE-SHIRLEY BASIN-
CENTRAL LARAMIE RANGE AND SOUTHWEST PLATTE COUNTY-
EAST PLATTE COUNTY-GOSHEN COUNTY-NORTH SNOWY RANGE FOOTHILLS-
SNOWY RANGE-LARAMIE VALLEY-SOUTH LARAMIE RANGE-
SOUTH LARAMIE RANGE FOOTHILLS-CENTRAL LARAMIE COUNTY-
EAST LARAMIE COUNTY-
658 PM MDT THU JUN 25 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF EAST CENTRAL
WYOMING...SOUTH CENTRAL WYOMING AND SOUTHEAST WYOMING.

.DAY ONE...TONIGHT

ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE POSSIBLE THIS
EVENING. THESE STORMS ARE NO LONGER EXPECTED TO BE SEVERE. DIME
SIZED HAIL AND DOWNBURST WINDS TO 40 MPH ARE POSSIBLE WITH THE
STRONGER STORMS THIS EVENING.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

ISOLATED MAINLY LATE DAY THUNDERSTORMS ARE POSSIBLE MAINLY FRIDAY
AND TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

WYZ104-109-111>113-270100-
FERRIS/SEMINOE/SHIRLEY MOUNTAINS-CENTRAL CARBON COUNTY-
SOUTHWEST CARBON COUNTY-SIERRA MADRE RANGE-
UPPER NORTH PLATTE RIVER BASIN-
658 PM MDT THU JUN 25 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTH CENTRAL
WYOMING.

.DAY ONE...TONIGHT

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION WILL NOT BE NEEDED TONIGHT.

In the hours before

Local storm report, Jun 25, 6:40 PM MDT, 1 hour 2 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
640 PM MDT THU JUN 25 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0545 PM     HAIL             ALLIANCE                42.10N 102.87W
06/25/2015  E1.75 INCH       BOX BUTTE          NE   TRAINED SPOTTER

&&

KC

Local storm report, Jun 25, 6:43 PM MDT, 59 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE CHEYENNE WY
643 PM MDT THU JUN 25 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0535 PM     TSTM WND GST     9 N ALLIANCE            42.23N 102.87W
06/25/2015  E65 MPH          BOX BUTTE          NE   NWS EMPLOYEE

            NATIONAL WEATHER SERVICE EMPLOYEE DRIVING THROUGH THE
            AREA ENCOUNTERED 65 MPH WINDS AND 1.25 INCH DIAMETER HAIL
            NORTH OF ALLIANCE

&&

TTRUDEL

Local storm report, Jun 25, 6:51 PM MDT, 51 minutes before

PRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE CHEYENNE WY
651 PM MDT THU JUN 25 2015

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0918 AM     HAIL             17 NE DOUGLAS           42.93N 105.16W
06/25/2015  E1.00 INCH       CONVERSE           WY   TRAINED SPOTTER

1052 AM     HAIL             11 N CRAWFORD           42.84N 103.41W
06/25/2015  E0.50 INCH       DAWES              NE   TRAINED SPOTTER

1230 PM     HEAVY RAIN       CHADRON ST PARK         42.68N 103.00W
06/25/2015  M2.60 INCH       DAWES              NE   PARK/FOREST SRVC

1245 PM     TSTM WND GST     HEMINGFORD              42.32N 103.08W
06/25/2015  E50.00 MPH       BOX BUTTE          NE   TRAINED SPOTTER

0118 PM     HAIL             6 NE ALLIANCE           42.16N 102.79W
06/25/2015  E4.25 INCH       BOX BUTTE          NE   PUBLIC

0118 PM     HAIL             5 NNE ALLIANCE          42.17N 102.84W
06/25/2015  M1.75 INCH       BOX BUTTE          NE   FIRE DEPT/RESCUE

0120 PM     HAIL             7 NE ALLIANCE           42.17N 102.78W
06/25/2015  E1.75 INCH       BOX BUTTE          NE   TRAINED SPOTTER

0120 PM     HAIL             3 NE ALLIANCE           42.13N 102.83W
06/25/2015  E1.75 INCH       BOX BUTTE          NE   PUBLIC

            HAIL LASTED FROM 120 TO 127PM. 55MPH WIND GUSTS MEASURED.
            WINDOWS BROKEN OUT OF GARAGE AND BASEMENT. 0.31 INCHES OF
            LIQUID MEASURED.

0400 PM     HAIL             19 W WHEATLAND          42.05N 105.33W
06/25/2015  E0.75 INCH       ALBANY             WY   TRAINED SPOTTER

0409 PM     HAIL             8 N WHEATLAND           42.17N 104.96W
06/25/2015  E0.75 INCH       PLATTE             WY   TRAINED SPOTTER

0420 PM     HAIL             5 NE WHEATLAND          42.10N 104.89W
06/25/2015  E0.50 INCH       PLATTE             WY   TRAINED SPOTTER

0438 PM     HAIL             CRAWFORD                42.69N 103.41W
06/25/2015  E1.75 INCH       DAWES              NE   LAW ENFORCEMENT

0438 PM     HAIL             CRAWFORD                42.69N 103.41W
06/25/2015  E1.75 INCH       DAWES              NE   LAW ENFORCEMENT

0512 PM     HAIL             7 N HEMINGFORD          42.42N 103.08W
06/25/2015  E1.50 INCH       BOX BUTTE          NE   TRAINED SPOTTER

0523 PM     TORNADO          2 N BAYARD              41.79N 103.32W
06/25/2015                   MORRILL            NE   TRAINED SPOTTER

0524 PM     HAIL             HEMINGFORD              42.32N 103.08W
06/25/2015  E1.75 INCH       BOX BUTTE          NE   TRAINED SPOTTER

0525 PM     TORNADO          1 NE BAYARD             41.77N 103.31W
06/25/2015                   MORRILL            NE   TRAINED SPOTTER

0525 PM     HAIL             2 NW HEMINGFORD         42.34N 103.10W
06/25/2015  E3.00 INCH       BOX BUTTE          NE   PUBLIC

            VIA TWITTER PICTURE

0527 PM     TORNADO          3 N BAYARD              41.80N 103.32W
06/25/2015                   MORRILL            NE   TRAINED SPOTTER

            TORNADO JUST WENT BY HIS HOUSE. 1/8 MILE WIDE. GOLF BALL
            SIZED HAIL.

0535 PM     TSTM WND GST     9 N ALLIANCE            42.23N 102.87W
06/25/2015  E65.00 MPH       BOX BUTTE          NE   NWS EMPLOYEE

            NATIONAL WEATHER SERVICE EMPLOYEE DRIVING THROUGH THE
            AREA ENCOUNTERED 65 MPH WINDS AND 1.25 INCH DIAMETER HAIL
            NORTH OF ALLIANCE

0540 PM     HAIL             3 E BAYARD              41.76N 103.26W
06/25/2015  E1.50 INCH       MORRILL            NE   TRAINED SPOTTER

0545 PM     HAIL             ALLIANCE                42.10N 102.87W
06/25/2015  E1.75 INCH       BOX BUTTE          NE   TRAINED SPOTTER

0553 PM     HAIL             ALLIANCE                42.10N 102.87W
06/25/2015  E1.00 INCH       BOX BUTTE          NE   PUBLIC

0619 PM     FLASH FLOOD      BRIDGEPORT              41.67N 103.10W
06/25/2015                   MORRILL            NE   PUBLIC

            PICTURE POSTED ON TWITTER.

&&

TTRUDEL

Special weather statement, Jun 25, 6:52 PM MDT, 50 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE CHEYENNE WY
652 PM MDT THU JUN 25 2015

NEZ021-055-260130-
CHEYENNE NE-MORRILL NE-
652 PM MDT THU JUN 25 2015

...SIGNIFICANT WEATHER ADVISORY FOR CHEYENNE AND SOUTHERN MORRILL
COUNTIES UNTIL 730 PM MDT...

AT 651 PM MDT...DOPPLER RADAR WAS TRACKING A LINE OF STRONG
THUNDERSTORMS ALONG A LINE EXTENDING FROM NEAR DALTON TO 7 MILES
NORTHWEST OF LORENZO...AND MOVING EAST AT 45 MPH.

HALF INCH HAIL AND WIND GUSTS UP TO 50 MPH WILL BE POSSIBLE WITH
THESE STORMS.

LOCATIONS IMPACTED INCLUDE...
SIDNEY...LODGEPOLE...DALTON...GURLEY...SIDNEY AIRPORT...SUNOL...
LORENZO...COLTON AND BROWNSON.

THIS INCLUDES INTERSTATE 80 IN NEBRASKA BETWEEN MILE MARKERS 47 AND
77.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

TORRENTIAL RAINFALL IS ALSO OCCURRING WITH THESE STORMS...AND MAY
LEAD TO FLASH FLOODING. DO NOT DRIVE YOUR VEHICLE THROUGH FLOODED
ROADWAYS.

THESE STORMS MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4100 10263 4100 10321 4104 10331 4144 10294
      4137 10261 4105 10261
TIME...MOT...LOC 0051Z 290DEG 41KT 4136 10292 4108 10318

FINCH

Local storm report, Jun 25, 7:04 PM MDT, 38 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

Local storm report, Jun 25, 7:06 PM MDT, 36 minutes before

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Service Notice</title>
  <link rel="stylesheet" href="index.css">
</head>
<body>
  <main class="wrap">
    <section class="card" role="status" aria-live="polite">
      <div class="status" id="status">Temporary Notice</div>
      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
      </p>
      <p id="message2">
        Please try again in a few minutes.
      </p>
      <p class="small" id="detail">
        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
      </p>
    </section>
  </main>
  <script src="index.js"></script>
</body>
</html>

The office that day

Everything else NWS Cheyenne, WY issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 25, 6:12 PM MDT	Special Weather Statement	CYS	Platte	48 min
Jun 25, 7:55 PM MDT	Special Weather Statement	CYS	Laramie	35 min
Jun 25, 6:03 PM MDT	Special Weather Statement	CYS	Scotts Bluff	42 min
Jun 25, 6:13 PM MDT	Flash Flood Warning	CYS	Banner, Morrill, Scotts Bluff	4 hr
Jun 25, 6:52 PM MDT	Special Weather Statement	CYS	Cheyenne	38 min
Jun 25, 7:01 PM MDT	Severe Thunderstorm Warning	CYS	Cheyenne	29 min

Nearby

Severe Thunderstorm Warnings in Wyoming, 2015 Every severe thunderstorm warning in 2015

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.