Alert archive / North Dakota / Mesoscale Discussions in 2012

Mesoscale Discussion 778

May 10, 201213 counties in North Dakota; Corson County, Perkins County, Ziebach County, South Dakota

The Storm Prediction Center issued this mesoscale discussion at May 10, 2012, 4:48 PM CDT for 13 counties in North Dakota; Corson County, Perkins County, Ziebach County, South Dakota. It was in force for 87 min.

The area

The outline as issued.

The facts

Issued
May 10, 2012, 4:48 PM CDT (21:48 UTC)
Expired
May 10, 2012, 6:15 PM CDT
In force
87 min
Issued by
the Storm Prediction Center
Chance of a watch
20%

Counties Benson County, ND, Burleigh County, ND, Grant County, ND, McHenry County, ND, McLean County, ND, Morton County, ND, Oliver County, ND, Pierce County, ND, Rolette County, ND, Sheridan County, ND, Sioux County, ND, Towner County, ND, Wells County, ND, Corson County, SD, Perkins County, SD, Ziebach County, SD

The radar

The Bismarck radar (KBIS), 7 km from the middle of the area, began a volume at 21:49 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

Bismarck Municip, ND (KBIS), launched 12:00Z, 9.8 hours before the alert went out and 10 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, Bismarck Municip, ND at 12:00Z on 2012-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Bismarck Municip, ND at 12:00Z on 2012-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 143 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
1940 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
143 m²/s²
0-3 km storm-relative helicity
128 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

129 
ACUS11 KWNS 102149
SWOMCD
SPC MCD 102148
NDZ000-SDZ000-102315-

MESOSCALE DISCUSSION 0778
NWS STORM PREDICTION CENTER NORMAN OK
0448 PM CDT THU MAY 10 2012

AREAS AFFECTED...CNTRL ND AND NCNTRL SD

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 102148Z - 102315Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...A MARGINAL SEVERE THREAT IS LIKELY TO DEVELOP BY EARLY
THIS EVENING FROM CNTRL ND SSWWD INTO NCNTRL SD. HAIL AND STRONG
GUSTY WINDS WILL BE POSSIBLE AS STORMS INTENSIFY BUT THE THREATS ARE
EXPECTED TO REMAIN TOO MARGINAL TO WARRANT WW ISSUANCE.

DISCUSSION...THE LATEST VISIBLE SATELLITE IMAGERY SHOWS AN AGITATED
FIELD OF CUMULUS LOCATED JUST TO THE WEST OF BISMARK EXTENDING SSWWD
TO NEAR FAITH SD. THE CUMULUS IS LOCATED ALONG A COLD FRONT SURGING
SEWD WITH SHORT-TERM MODEL FORECASTS IN AGREEMENT CONCERNING THE
INITIATION OF CONVECTION ALONG AND BEHIND THE BOUNDARY. SFC
DEWPOINTS AHEAD OF THE FRONT ARE IN THE UPPER 40S F WITH SFC TEMPS
IN THE MID 80S F...HELPING TO YIELD MLCAPE VALUES OF 500 TO 750
J/KG. THIS COMBINED WITH 40 TO 50 KT OF DEEP LAYER SHEAR NEAR THE
BOUNDARY WITH MID-LEVEL LAPSE RATES OF 8.0 TO 8.5 C/KM SHOULD BE
SUFFICIENT FOR HAIL AS STORMS INITIATE AND INCREASE IN COVERAGE. IN
ADDITION...SFC TEMP-DEWPOINT SPREADS OF 30 TO 35 DEGREES MAY HELP
ENHANCE DOWNDRAFTS ENOUGH FOR SOME STRONG WIND GUSTS.

..BROYLES.. 05/10/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...FGF...ABR...BIS...UNR...

LAT...LON   45020240 44820188 44870143 45120106 45700076 47009990
            47999910 48839878 49149898 49210006 48980065 48090137
            45730257 45020240

Nearby

Mesoscale Discussions in North Dakota, 2012Mesoscale Discussions in South Dakota, 2012Every mesoscale discussion in 2012

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.