Alert archive / Colorado / Mesoscale Discussions in 2011
Mesoscale Discussion 1449
The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2011, 11:57 AM MDT for 20 counties in Colorado; 7 counties in Nebraska; 8 counties in Wyoming. It was in force for 63 min.
The area
The outline as issued.
The facts
- Issued
- Jun 30, 2011, 11:57 AM MDT (17:57 UTC)
- Expired
- Jun 30, 2011, 1:00 PM MDT
- In force
- 63 min
- Issued by
- the Storm Prediction Center
All 35 counties
Adams County, CO, Boulder County, CO, Broomfield County, CO, Chaffee County, CO, Clear Creek County, CO, Denver County, CO, Douglas County, CO, Eagle County, CO, Gilpin County, CO, Grand County, CO, Gunnison County, CO, Jackson County, CO, Jefferson County, CO, Lake County, CO, Larimer County, CO, Morgan County, CO, Park County, CO, Pitkin County, CO, Summit County, CO, Weld County, CO, Banner County, NE, Box Butte County, NE, Cheyenne County, NE, Kimball County, NE, Morrill County, NE, Scotts Bluff County, NE, Sioux County, NE, Albany County, WY, Carbon County, WY, Converse County, WY, Goshen County, WY, Laramie County, WY, Niobrara County, WY, Platte County, WY, Sweetwater County, WY
The radar
The Cheyenne radar (KCYS), 110 km from the middle of the area, began a volume at 17:56 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.
The nearest sounding before it
Denver, CO (KDNR), launched 12:00Z, 6.0 hours before the alert went out and 281 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 2394 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 27 m²/s²
- 0-3 km storm-relative helicity
- 89 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
665
ACUS11 KWNS 301757
SWOMCD
SPC MCD 301757
NEZ000-COZ000-WYZ000-301900-
MESOSCALE DISCUSSION 1449
NWS STORM PREDICTION CENTER NORMAN OK
1257 PM CDT THU JUN 30 2011
AREAS AFFECTED...SRN/SERN WY...CNTRL/NCNTRL/NERN CO...NEB PNHDL
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY
VALID 301757Z - 301900Z
STRONG-SEVERE THUNDERSTORMS WITH DAMAGING WINDS AND LARGE HAIL WILL
BE LIKELY THROUGH THE AFTERNOON. STORMS WILL SPREAD ENE FROM SCNTRL
WY AND WRN CO TO THE HIGH PLAINS BY MID-AFTERNOON AND A WEATHER
WATCH WILL BE LIKELY...GREATER THAN 80 PERCENT FOR PARTS OF THE
AREA.
STRONG PV-ANOMALY WAS CENTERED OVER SCNTRL UT AT 18Z AND WILL MOVE
INTO WRN CO THIS AFTERNOON. STRONG LARGE-SCALE ASCENT SPREADING
DOWNSTREAM TOWARD THE HIGH PLAINS COUPLED WITH VERY STEEP LAPSE
RATES AND 1000 J/KG MLCAPES WILL LIKELY AID IN MAINTENANCE AND
FORMATION OF TSTMS ACROSS THE DISCUSSION AREA THIS AFTERNOON.
DEEP SWLY TROPOSPHERIC FLOW ALONG BASE OF THE SYSTEM /50-60 KTS AT
500 MB/ WILL BE FAVORABLE FOR THE HIGH-BASED STORMS TO BOW WITH
DAMAGING WINDS A THREAT. HOWEVER...DIURNAL UPSLOPE FLOW EAST OF THE
DIVIDE WILL ACT TO ENHANCE THE VERTICAL SHEAR AND
LONGER-LIVED...HIGH-BASED SUPERCELLS WILL BE POSSIBLE ACROSS SERN
WY...NEB PNHDL AND NERN CO AMID SLIGHTLY STRONGER BUOYANCY/LOW-LEVEL
MOISTURE. HERE...LARGE HAIL WILL BE AN ADDITIONAL THREAT BEFORE
COLD POOLS BEGIN TO DOMINATE.
..RACY.. 06/30/2011
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...LBF...PUB...BOU...CYS...RIW...GJT...
LAT...LON 38240722 40360687 40850686 41050707 41160898 41430924
41860939 42330836 42800675 43280542 43090438 42660359
42310281 41710243 40890316 39370470 38410571 38240722SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 30, 8:51 AM MDT | Mesoscale Discussion | SPC | Delta, Dolores, Eagle, Garfield, Gunnison, Hinsdale and 10 more | 54 min |
| Jun 30, 9:06 AM MDT | Severe Thunderstorm Watch | SPC | Delta, Dolores, Eagle, Garfield, Gunnison, La Plata and 10 more | 7 hr |
| Jun 30, 12:18 PM MDT | Severe Thunderstorm Watch | SPC | Adams, Arapahoe, Boulder, Broomfield, Chaffee, Clear Creek and 17 more | 9 hr |
| Jun 30, 1:49 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Boulder, Broomfield, Clear Creek, Delta and 25 more | 116 min |
| Jun 30, 4:17 PM MDT | Mesoscale Discussion | SPC | Adams, Arapahoe, Boulder, Broomfield, Chaffee, Clear Creek and 25 more | 118 min |
| Jun 30, 2:19 PM MDT | Mesoscale Discussion | SPC | Arthur, Cherry, Grant, Hooker, Keith, McPherson and 1 more | 56 min |
| Jun 30, 4:39 PM MDT | Severe Thunderstorm Watch | SPC | Arthur, Brown, Cherry, Deuel, Garden, Grant and 9 more | 5 hr |
Nearby
Mesoscale Discussions in Colorado, 2011Mesoscale Discussions in Wyoming, 2011Mesoscale Discussions in Nebraska, 2011Every mesoscale discussion in 2011
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.