Alert archive / Colorado / Mesoscale Discussions in 2010

Mesoscale Discussion 1221

July 6, 20105 counties in Colorado

The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2010, 7:21 PM MDT for 5 counties in Colorado. It was in force for 54 min.

The area

The outline as issued.

The facts

Issued
Jul 6, 2010, 7:21 PM MDT (01:21 UTC)
Expired
Jul 6, 2010, 8:15 PM MDT
In force
54 min
Issued by
the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, El Paso County, CO, Elbert County, CO, Morgan County, CO

The radar

The Denver radar (KFTG), 49 km from the middle of the area, began a volume at 01:25 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 (KDNR), launched 00:00Z, 1.4 hours before the alert went out and 80 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, Denver, CO at 00:00Z on 2010-07-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 152 joules per kilogram.LCLLFCEL10008507005003002001001 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, Denver, CO at 00:00Z on 2010-07-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 73 square meters per square second.1939Sfc1 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
152 J/kg
Mixed-layer CIN
-68 J/kg
Mixed-layer LCL
3141 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
73 m²/s²
0-3 km storm-relative helicity
87 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.

503 
ACUS11 KWNS 070122
SWOMCD
SPC MCD 070121
COZ000-070215-

MESOSCALE DISCUSSION 1221
NWS STORM PREDICTION CENTER NORMAN OK
0821 PM CDT TUE JUL 06 2010

AREAS AFFECTED...NERN CO

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 070121Z - 070215Z

A LINE OF STRONG TO MARGINALLY SEVERE THUNDERSTORMS HAS FORMED TO
THE EAST OF THE DENVER METRO AREA IN A CONFLUENCE ZONE ASSOCIATED
WITH A WEAK LEE TROUGH AND OUTFLOW BOUNDARY. THE THUNDERSTORMS
CURRENTLY EXIST WITHIN A MODERATELY UNSTABLE ENVIRONMENT /MUCAPE
VALUES AROUND 2000 J/KG PER MODIFIED 00Z DNR SOUNDING AND OBJECTIVE
ANALYSIS PLOTS/. AREA VWP/PROFILER DATA INDICATE EFFECTIVE WIND
SHEAR VALUES OF AROUND 20-25 KTS OVER THE REGION...FAVORING A
MULTICELLULAR MODE /AS CURRENTLY OBSERVED IN RADAR DATA/. IN
ADDITION...A SOMEWHAT DRY/WELL-MIXED BOUNDARY LAYER WITH SFC T-TD
SPREAD IN EXCESS OF 30 DEG F OVER ERN CO WILL LIKELY LEAD TO THE
DEVELOPMENT OF A STRONG COLD POOL...WHICH COULD YIELD SOME
MARGINALLY SEVERE CONVECTIVE WIND GUSTS. MARGINALLY SEVERE HAIL WILL
BE POSSIBLE WITH THE STRONGER CORES GIVEN THE STEEP MID-LEVEL LAPSE
RATES...BUT WEAK VERTICAL SHEAR PROFILES WILL PRECLUDE A MORE
SUBSTANTIAL HAIL THREAT FROM BEING REALIZED.

SHORT-TERM MODEL GUIDANCE INDICATES THAT CONVECTION MAY BE
MAINTAINED FOR THE NEXT SEVERAL HRS OVER ERN CO. HOWEVER...WITH THE
LOSS OF HEATING/RESULTANT DECREASE IN INSTABILITY...THE THREAT FOR
CONVECTIVELY DRIVEN DAMAGING WINDS AND HAIL SHOULD DECREASE. A WW IS
NOT ANTICIPATED.

..ROGERS.. 07/07/2010

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

ATTN...WFO...PUB...BOU...

LAT...LON   39230381 38790415 38650434 38650461 39050483 39800471
            40280437 40470391 40500352 40260319 39700349 39230381

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 6, 8:20 PM MDTMesoscale DiscussionSPCAdams, Broomfield, Logan, Morgan, Phillips, Sedgwick and 2 more25 min

Nearby

Mesoscale Discussions in Colorado, 2010Every mesoscale discussion in 2010

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.