Alert archive / Minnesota / Mesoscale Discussions in 2003

Mesoscale Discussion 2014

July 29, 200328 counties in Minnesota; Richland County, North Dakota; 25 counties in South Dakota

The Storm Prediction Center issued this mesoscale discussion at Jul 29, 2003, 3:09 PM CDT for 28 counties in Minnesota; Richland County, North Dakota; 25 counties in South Dakota. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 29, 2003, 3:09 PM CDT (20:09 UTC)
Expired: Jul 29, 2003, 5:15 PM CDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 54 counties

Becker County, MN, Beltrami County, MN, Big Stone County, MN, Cass County, MN, Chippewa County, MN, Clay County, MN, Clearwater County, MN, Douglas County, MN, Grant County, MN, Hubbard County, MN, Lac qui Parle County, MN, Lincoln County, MN, Lyon County, MN, Mahnomen County, MN, Marshall County, MN, Norman County, MN, Otter Tail County, MN, Pennington County, MN, Polk County, MN, Pope County, MN, Red Lake County, MN, Stevens County, MN, Swift County, MN, Todd County, MN, Traverse County, MN, Wadena County, MN, Wilkin County, MN, Yellow Medicine County, MN, Richland County, ND, Aurora County, SD, Beadle County, SD, Brookings County, SD, Brule County, SD, Buffalo County, SD, Clark County, SD, Codington County, SD, Davison County, SD, Day County, SD, Deuel County, SD, Douglas County, SD, Grant County, SD, Hamlin County, SD, Hand County, SD, Hanson County, SD, Jerauld County, SD, Kingsbury County, SD, Lake County, SD, Marshall County, SD, McCook County, SD, Miner County, SD, Moody County, SD, Roberts County, SD, Sanborn County, SD, Spink County, SD

The radar

The Aberdeen radar (KABR), 133 km from the middle of the area, began a volume at 20:12 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 watches that followed

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

Severe Thunderstorm Watch 814Jul 29, 5:10 PM CDT

The nearest sounding before it

Aberdeen, SD (KABR), launched 12:00Z, 8.2 hours before the alert went out and 169 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: 4 J/kg
Mixed-layer CIN: -422 J/kg
Mixed-layer LCL: 1942 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: 38 m²/s²
0-3 km storm-relative helicity: 143 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.

125 
ACUS11 KWNS 292009
SWOMCD
SPC MCD 292009 
MNZ000-SDZ000-NDZ000-292215-

MESOSCALE DISCUSSION 2014
NWS STORM PREDICTION CENTER NORMAN OK
0309 PM CDT TUE JUL 29 2003

AREAS AFFECTED...ERN ND/SD...WRN MN

CONCERNING...SEVERE THUNDERSTORM WATCH 811...813...

VALID 292009Z - 292215Z

ADDITIONAL WW MAY BE NEEDED ACROSS SOUTHWESTERN MINNESOTA WITHIN
NEXT HOUR OR TWO.

LATEST OBJECTIVE GUIDANCE INDICATES MEAN MIXED LAYER CAPE IS NOW
MAXIMIZED ALONG SURFACE TROUGH...FROM NEAR ABERDEEN SD THROUGH FARGO
ND INTO AREAS OF MINNESOTA EAST OF GRAND FORKS...WITH VALUES ON THE
ORDER OF 1500 TO 2000 J/KG.  AS DIFLUENT/DIVERGENT UPPER FLOW FIELD
OVERSPREADS THIS REGION...NEW CONVECTIVE DEVELOPMENT APPEARS LIKELY
WITHIN THE NEXT HOUR OR TWO.  THIS ACTIVITY WILL LIKELY MERGE WITH
ONGOING CONVECTION NOW SOUTH/SOUTHEAST OF THE ABERDEEN AND PIERRE
AREAS...GRADUALLY EVOLVING INTO MORE EXTENSIVE SQUALL LINE ACROSS
WESTERN MINNESOTA/EASTERN NORTH DAKOTA BY/SHORTLY AFTER 30/00Z.

GIVEN THERMODYNAMIC ENVIRONMENT WITH RELATIVELY DEEP MIXED BOUNDARY
LAYER...AND LOW RELATIVE HUMIDITIES IN LOWER/MID-LEVELS...DAMAGING
WIND GUSTS SHOULD BECOME INCREASING THREAT WITH DEVELOPING SQUALL
LINE.  MODELS SUGGEST SOUTH SOUTHWESTERLY LOW-LEVEL FLOW INCREASING
IN EXCESS OF 20 KT ALONG LENGTH OF SQUALL LINE BY EARLY
EVENING...AND DOWNWARD TRANSFER OF THIS MOMENTUM MAY ENHANCE PEAK
GUSTS.

..KERR.. 07/29/2003

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

ATTN...WFO...DLH...MPX...FGF...FSD...ABR...UNR...

48569540 48269498 46929417 45449472 43999630 43229804
43469968 44319943 44689928 45269781 46819724 48299691

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 29, 12:42 PM CDT	Mesoscale Discussion	SPC	Clay, Norman, Polk, Red Lake, Traverse, Wilkin	108 min
Jul 29, 3:05 PM CDT	Severe Thunderstorm Watch	SPC	Becker, Beltrami, Clay, Clearwater, Kittson, Lake of the Woods and 9 more	6 hr
Jul 29, 5:10 PM CDT	Severe Thunderstorm Watch	SPC	Aitkin, Benton, Brown, Carlton, Carver, Cass and 40 more	5 hr
Jul 29, 1:40 PM CDT	Severe Thunderstorm Watch	SPC	Aurora, Beadle, Brule, Buffalo, Charles Mix, Clark and 20 more	5 hr

Nearby

Mesoscale Discussions in Minnesota, 2003 Mesoscale Discussions in South Dakota, 2003 Mesoscale Discussions in North Dakota, 2003 Every 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.