Alert archive / Colorado / Mesoscale Discussions in 2015
Mesoscale Discussion 2016
The Storm Prediction Center issued this mesoscale discussion at Dec 15, 2015, 2:55 AM MST for 6 counties in Colorado; Banner County, Cheyenne County, Kimball County, Nebraska. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Dec 15, 2015, 2:55 AM MST (09:55 UTC)
- Expired
- Dec 15, 2015, 7:00 AM MST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
Counties Adams County, CO, Arapahoe County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Weld County, CO, Banner County, NE, Cheyenne County, NE, Kimball County, NE
The radar
The Denver radar (KFTG), 68 km from the middle of the area, began a volume at 09:55 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
Denver, CO (KDEN), launched 00:00Z, 9.9 hours before the alert went out and 108 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
- 1835 m above ground
- 0-6 km bulk shear
- 63 kt
- 0-1 km storm-relative helicity
- 216 m²/s²
- 0-3 km storm-relative helicity
- 248 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
531
ACUS11 KWNS 150956
SWOMCD
SPC MCD 150955
NEZ000-COZ000-WYZ000-151400-
MESOSCALE DISCUSSION 2016
NWS STORM PREDICTION CENTER NORMAN OK
0355 AM CST TUE DEC 15 2015
AREAS AFFECTED...CO FRONT RANGE/HIGH PLAINS...SERN WY...NE PANHANDLE
CONCERNING...HEAVY SNOW
VALID 150955Z - 151400Z
SUMMARY...HEAVY SNOWFALL RATES AROUND 1 INCH PER HOUR WILL BECOME
MORE WIDESPREAD OVER THE CO FRONT RANGE THROUGH 12Z AND BEGIN TO
SHIFT NEWD INTO ADJACENT PORTIONS OF NE AND WY. 2 INCHES PER HOUR
RATES FOR AN HOUR OR TWO WILL BE POSSIBLE IN LOCALIZED AREAS.
DISCUSSION...RADAR MOSAIC AND SURFACE OBSERVATIONS TRENDS SHOW
INTENSIFYING SNOWFALL RATES ALONG THE CO I-25 CORRIDOR FROM NEAR THE
PALMER DIVIDE NWD INTO THE FRONT RANGE VICINITY DURING THE
0845-0945Z PERIOD. A SURFACE LOW OVER E-CNTRL CO WILL DEVELOP ENEWD
INTO NWRN KS THROUGH MIDDAY AS STRENGTHENING UPWARD VERTICAL MOTION
/DCVA/ OVERSPREAD THE CNTRL HIGH PLAINS. STRONG UPSLOPE FLOW AND A
COLD PROFILE SUPPORTIVE OF SNOW WILL GRADUALLY SATURATE THE COLUMN
NEAR THE WY/NE/CO BORDER REGION DURING THE NEXT FEW HOURS.
EXPERIMENTAL OPRH VALUES INDICATING INCREASING MID-LEVEL ASCENT
JUXTAPOSED THE DENDRITIC GROWTH LAYER SUGGEST HOURLY SNOWFALL RATES
AROUND 1 INCH PER HOUR WILL BECOME MORE PREVALENT ACROSS N-CNTRL CO
THROUGH 12Z. THE EXPERIMENTAL GUIDANCE SUGGESTS RATES MAY APPROACH
2 INCHES PER HOUR AS THE HEAVY SNOW DEVELOPS NEWD INTO THE SWRN
PORTION OF THE NE PANHANDLE DURING THE MID MORNING HOURS.
..SMITH.. 12/15/2015
...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...
ATTN...WFO...PUB...BOU...CYS...
LAT...LON 39570518 40440523 40900490 41700361 41690307 41150297
40270396 39270424 39120481 39570518SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Dec 15, 10:48 AM MST | Mesoscale Discussion | SPC | Cherry, Grant, Keya Paha, Sheridan | 4 hr |
Nearby
Mesoscale Discussions in Colorado, 2015Mesoscale Discussions in Nebraska, 2015Every mesoscale discussion in 2015
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.