Alert archive / Montana / Mesoscale Discussions in 2005
Mesoscale Discussion 1713
The Storm Prediction Center issued this mesoscale discussion at Jul 9, 2005, 2:42 PM MDT for 12 counties in Montana. It was in force for 2 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 9, 2005, 2:42 PM MDT (20:42 UTC)
- Expired
- Jul 9, 2005, 4:45 PM MDT
- In force
- 2 hr
- Issued by
- the Storm Prediction Center
Counties Big Horn County, MT, Custer County, MT, Dawson County, MT, McCone County, MT, Musselshell County, MT, Prairie County, MT, Richland County, MT, Roosevelt County, MT, Rosebud County, MT, Sheridan County, MT, Treasure County, MT, Yellowstone County, MT
The radar
The Glasgow radar (KGGW), 129 km from the middle of the area, began a volume at 20:42 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, 8.7 hours before the alert went out and 131 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.
- Mixed-layer CAPE
- 898 J/kg
- Mixed-layer CIN
- -592 J/kg
- Mixed-layer LCL
- 1917 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 117 m²/s²
- 0-3 km storm-relative helicity
- 133 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 ACUS11 KWNS 092042 SWOMCD SPC MCD 092042 NDZ000-MTZ000-092245- MESOSCALE DISCUSSION 1713 NWS STORM PREDICTION CENTER NORMAN OK 0342 PM CDT SAT JUL 09 2005 AREAS AFFECTED...S CNTRL THROUGH ERN MT AND EXTREME WRN ND CONCERNING...SEVERE THUNDERSTORM POTENTIAL VALID 092042Z - 092245Z THUNDERSTORMS MAY DEVELOP INITIALLY OVER S CNTRL MT THIS AFTERNOON THEN NEWD THROUGH ERN MT AND PARTS OF WRN ND THIS EVENING. ISOLATED LARGE HAIL AND DAMAGING WIND WILL BE THE PRIMARY THREATS. AREA IS BEING MONITORED FOR A POSSIBLE WW ISSUANCE WITHIN THE NEXT COUPLE OF HOURS. THIS AFTERNOON A COLD FRONT EXTENDS FROM ERN MT SWWD INTO SERN AND S CNTRL MT JUST N OF BILLINGS. SRN PORTION OF THIS BOUNDARY IS MOVING SWD WHILE THE NRN PORTION CONTINUES SLOWLY EWD THROUGH ERN MT. LOW LEVEL DEWPOINTS ARE IN THE 50S N OF THE FRONT...AND AS THIS BOUNDARY CONTINUES SWD...MOIST NLY UPSLOPE FLOW WILL DEVELOP OVER S CNTRL MT. POTENTIAL FOR INCREASING UPSLOPE IN CONJUNCTION WITH INCREASING MID LEVEL ASCENT ASSOCIATED WITH APPROACHING SHORTWAVE TROUGH MAY PROMOTE THE DEVELOPMENT OF THUNDERSTORMS OVER THE HIGHER TERRAIN OF S CNTRL MT. ACTIVITY WILL SUBSEQUENTLY SPREAD NEWD WHERE STRONG SURFACE HEATING IS PROMOTING MLCAPE FROM 1500 TO 2000 J/KG. FARTHER NE ACROSS ERN MT THE PRE-FRONTAL WARM SECTOR REMAINS CAPPED...BUT THE CAP SHOULD GRADUALLY WEAKEN AS SURFACE TEMPERATURES APPROACH OR EXCEED 100F. THE WEAKENING CAP AND FRONTAL CONVERGENCE SHOULD PROMOTE THE DEVELOPMENT OF STORMS ALONG THE FRONT OVER ERN MT DURING THE EVENING...EVENTUALLY SPREADING INTO WRN ND. ..DIAL.. 07/09/2005 ...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT... ATTN...WFO...BIS...BYZ...GGW... 46800793 47420624 48810499 48950403 48350363 47010423 45860548 45250726 45940915 46420914
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 9, 2:07 PM MDT | Mesoscale Discussion | SPC | Big Horn, Carbon, Gallatin, Golden Valley, Madison, Musselshell and 5 more | 113 min |
Nearby
Mesoscale Discussions in Montana, 2005Every mesoscale discussion in 2005
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.