Alert archive / Montana / Mesoscale Discussions in 2003

Mesoscale Discussion 1127

May 26, 200315 counties in Montana

The Storm Prediction Center issued this mesoscale discussion at May 26, 2003, 5:10 PM MDT for 15 counties in Montana. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
May 26, 2003, 5:10 PM MDT (23:10 UTC)
Expired
May 26, 2003, 7:15 PM MDT
In force
2 hr
Issued by
the Storm Prediction Center

Counties Big Horn County, MT, Custer County, MT, Dawson County, MT, Fallon County, MT, Garfield County, MT, McCone County, MT, Musselshell County, MT, Petroleum County, MT, Powder River County, MT, Prairie County, MT, Richland County, MT, Rosebud County, MT, Treasure County, MT, Wibaux County, MT, Yellowstone County, MT

The radar

The Glasgow radar (KGGW), 182 km from the middle of the area, began a volume at 23:14 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

Glasgow Intl Airport, MT (KGGW), launched 12:00Z, 11.2 hours before the alert went out and 183 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, Glasgow Intl Airport, MT at 12:00Z on 2003-05-26Temperature 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, Glasgow Intl Airport, MT at 12:00Z on 2003-05-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 85 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
1390 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
85 m²/s²
0-3 km storm-relative helicity
196 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.

018 
ACUS11 KWNS 262311
SWOMCD
SPC MCD 262310 
NDZ000-MTZ000-270115-

MESOSCALE DISCUSSION 1127
NWS STORM PREDICTION CENTER NORMAN OK
0610 PM CDT MON MAY 26 2003

AREAS AFFECTED...ERN MT/WRN ND

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 262310Z - 270115Z

CONDITIONS APPEAR TO BE FAVORABLE FOR MORE WIDESPREAD STRONG TO
SEVERE TSTM DEVELOPMENT ACROSS PARTS OF ERN MT AND WRN ND THIS
EVENING. A SEVERE TSTM WATCH MAY BE NEEDED OVER THE REGION WITHIN
THE NEXT 1-2 HOURS.

CURRENT ANALYSIS INDICATED STRONG THERMAL TROUGH SITUATED FROM SERN
MT NNEWD ALONG THE MT/ND BORDER. THE LEADING EDGE OF COOLER/DRIER
SURFACE AIR INTERSECTED THE TROUGH OVER NERN MT...AND THEN TRAILED
SWWD TO SOUTH-CNTRL MT. AIRMASS WITHIN THE TROUGH AXIS AND AHEAD OF
THE COLD FRONT HAS BECOME STRONGLY UNSTABLE WITH LATEST MLCAPE
ESTIMATED AROUND 1500 J/KG. WITH THE EXCEPTION OF ISOLD CELLS
CURRENTLY OVER YELLOWSTONE AND TREASURE COUNTIES...IT APPEARS THAT
CONVECTION FROM ERN MT INTO ND BORDER AREA MAY BE STRUGGLING AGAINST
STRONGER CAP OVER THIS AREA. HOWEVER...FORCING ALONG THE COLD FRONT
AND TROUGH...COUPLED WITH CONTINUED HEATING AND FAVORABLY DIFFLUENT
MID LEVEL FLOW...SHOULD RESULT IN ADDITIONAL TSTM DEVELOP ACROSS THE
REGION OVER THE NEXT FEW HOURS. EXPECT UPSLOPE/POST-FRONTAL FLOW MAY
ALSO SUSTAIN STORMS ACROSS PORTIONS OF SERN MT LATER TONIGHT.
ACTIVITY SHOULD BECOME INCREASINGLY ORGANIZED AS FASTER SWLY MID
LEVEL FLOW SPREADS EWD ACROSS THE AREA THROUGH THE EVENING. DEGREE
OF INSTABILITY AND SUSTAINED LIFT ACROSS THE REGION SUGGESTS
INCREASING PROBABILITY OF SEVERE STORMS WITH HAIL AND HIGH WINDS.

..CARBIN.. 05/26/2003

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

ATTN...WFO...BIS...GGW...BYZ...TFX...

46060406 45320566 45450847 47260856 48250650 48190365

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 26, 2:52 PM MDTMesoscale DiscussionSPCCarter, Custer, Dawson, Fallon, Powder River, Prairie and 2 more83 min

Nearby

Mesoscale Discussions in Montana, 2003Every mesoscale discussion in 2003

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.