Alert archive / North Dakota / Mesoscale Discussions in 2012

Mesoscale Discussion 869

May 22, 201226 counties in North Dakota

The Storm Prediction Center issued this mesoscale discussion at May 22, 2012, 3:44 PM CDT for 26 counties in North Dakota. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued: May 22, 2012, 3:44 PM CDT (20:44 UTC)
Expired: May 22, 2012, 5:15 PM CDT
In force: 91 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 26 counties

Benson County, ND, Bottineau County, ND, Burke County, ND, Burleigh County, ND, Dunn County, ND, Eddy County, ND, Emmons County, ND, Foster County, ND, Grant County, ND, Kidder County, ND, Logan County, ND, McHenry County, ND, McLean County, ND, Mercer County, ND, Morton County, ND, Mountrail County, ND, Oliver County, ND, Pierce County, ND, Ramsey County, ND, Renville County, ND, Rolette County, ND, Sheridan County, ND, Stutsman County, ND, Ward County, ND, Wells County, ND, Williams County, ND

The watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 12:00Z, 8.7 hours before the alert went out and 111 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: 242 J/kg
Mixed-layer CIN: -610 J/kg
Mixed-layer LCL: 1843 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 103 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

The text

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

019 
ACUS11 KWNS 222044
SWOMCD
SPC MCD 222044 
NDZ000-222215-

MESOSCALE DISCUSSION 0869
NWS STORM PREDICTION CENTER NORMAN OK
0344 PM CDT TUE MAY 22 2012

AREAS AFFECTED...WRN/CNTRL ND

CONCERNING...SEVERE POTENTIAL...WATCH LIKELY 

VALID 222044Z - 222215Z

PROBABILITY OF WATCH ISSUANCE...80 PERCENT

SUMMARY...THUNDERSTORM DEVELOPMENT IS EXPECTED OVER PORTIONS OF WRN
AND CNTRL ND BY EARLY EVENING...WITH ACTIVITY SPREADING EWD AND
INCREASING IN COVERAGE DURING THE NIGHT. LARGE/VERY LARGE HAIL AND
DAMAGING WIND GUSTS WILL BE THE PRIMARY SVR WEATHER THREATS...BUT A
FEW TORNADOES WILL BE POSSIBLE AS WELL.

DISCUSSION...AT 20Z...SURFACE OBSERVATIONS SHOW AN AREA OF LOW
PRESSURE CONSOLIDATING OVER WRN ND...WITH A COLD FRONT ARCING S-SWWD
INTO WRN SD...AND A WARM FRONT EXTENDING EWD INTO ERN ND. S OF THE
WARM FRONT...TEMPERATURES ARE WARMING TO NEAR 80F...WHILE DEWPOINTS
HAVE INCREASED TO NEAR 60F. PLUME OF STEEP MIDLEVEL LAPSE RATES ALSO
RESIDES ACROSS THE REGION...WHICH IS AIDING IN MLCAPE VALUES FROM
1000-2000 J/KG. 

LATEST WV IMAGERY SHOWS A LEAD SHORTWAVE IMPULSE ASSOCIATED WITH
EXIT REGION OF 100+ KT UPR JET EJECTING EWD ACROSS ERN MT...WITH A
PLUME OF ASCENT SPREADING INTO THE NRN PLAINS. THE UPR SUPPORT
COMBINED WITH STRONG LOW-LEVEL CONVERGENCE INVOF THE SURFACE LOW
WILL FAVOR THUNDERSTORM DEVELOPMENT BY EARLY EVENING...WITH
ADDITIONAL STORM DEVELOPMENT LIKELY TO THE S ALONG THE COLD FRONT
SOON AFTER. 

THE BIS VWP SHOWS SURFACE WINDS OUT OF THE SE INCREASING IN SPEED
AND VEERING TO SLY AT 1 KM AGL...WITH FURTHER STRENGTHENING AND
VEERING TO SWLY IN THE MIDLEVELS. THIS WIND PROFILE IS YIELDING
STRONG LOW-LEVEL HODOGRAPH CURVATURE AND FAVORABLE DEEP-LAYER SHEAR
FOR SUPERCELLS. GIVEN THE PRESENCE OF STEEP MIDLEVEL LAPSE
RATES...STORMS WILL BE CAPABLE OF PRODUCING LARGE/VERY LARGE HAIL.
BY NIGHT...SVR THREAT MAY TRANSITION TO DAMAGING WINDS AS
STRENGTHENING ASCENT FAVORS UPSCALE GROWTH. IN ADDITION...LOW-LEVEL
SHEAR MAXIMIZED ALONG THE WARM FRONT...AS WELL AS LOWER LCL
HEIGHTS...MAY ENHANCE THE THREAT FOR A FEW TORNADOES.

..GARNER/WEISS.. 05/22/2012

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

ATTN...WFO...FGF...BIS...

LAT...LON   49050281 48970031 48319863 47309845 46479894 46020005
            46230186 47330308 48570388 49050281

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 22, 4:03 PM CDT	Tornado Watch	SPC	Barnes, Benson, Bottineau, Burke, Burleigh, Divide and 21 more	7 hr
May 22, 5:54 PM CDT	Severe Thunderstorm Watch	SPC	Cass, Dickey, Emmons, Grand Forks, LaMoure, Logan and 6 more	7 hr
May 22, 6:11 PM CDT	Mesoscale Discussion	SPC	Adams, Billings, Bowman, Hettinger, Slope, Stark	94 min
May 22, 6:54 PM CDT	Mesoscale Discussion	SPC	Benson, Bottineau, Burleigh, Eddy, Foster, Kidder and 9 more	96 min

Nearby

Mesoscale Discussions in North Dakota, 2012 Every 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.