Alert archive / Colorado / Mesoscale Discussions in 2003

Mesoscale Discussion 607

April 28, 200310 counties in Colorado

The Storm Prediction Center issued this mesoscale discussion at Apr 28, 2003, 1:05 PM MDT for 10 counties in Colorado. It was in force for 115 min.

The area

The outline as issued.

The facts

Issued: Apr 28, 2003, 1:05 PM MDT (19:05 UTC)
Expired: Apr 28, 2003, 3:00 PM MDT
In force: 115 min
Issued by: the Storm Prediction Center

Counties Adams County, CO, Arapahoe County, CO, Boulder County, CO, Broomfield County, CO, Denver County, CO, Douglas County, CO, Elbert County, CO, Jefferson County, CO, Morgan County, CO, Weld County, CO

The radar

The Denver radar (KFTG), 16 km from the middle of the area, began a volume at 19:09 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 12:00Z, 7.1 hours before the alert went out and 117 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 765 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 45 m²/s²
0-3 km storm-relative helicity: 84 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.

182 
ACUS11 KWNS 281906
SWOMCD
SPC MCD 281905 
COZ000-282100-

MESOSCALE DISCUSSION 0607
NWS STORM PREDICTION CENTER NORMAN OK
0205 PM CDT MON APR 28 2003

AREAS AFFECTED...NERN CO

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 281905Z - 282100Z

THUNDERSTORMS ARE EXPECTED TO DEVELOP IN THE FOOTHILLS OF THE
ROCKIES W OF DENVER OVER THE NEXT FEW HOURS. AS THE CONVECTION MOVES
EWD OUT OF THE FOOTHILLS AND INTO THE HIGH PLAINS...ISOLATED HAIL
AND/OR WIND GUSTS WILL BE POSSIBLE. WW MAY BE NECESSARY LATER THIS
AFTERNOON.

PRESSURE FALLS AND BACKING WINDS ALONG THE I-25 CORRIDOR ALONG THE
FRONT RANGE IN NCNTRL CO INDICATE THAT THE DENVER CYCLONE IS
DEVELOPING. CONVERGENCE ASSOCIATED WITH THIS FEATURE AND TOPOGRAPHIC
FORCING SHOULD ALLOW THUNDERSTORMS TO INITIATE IN THE FOOTHILLS AND
MOVE EWD INTO THE HIGH PLAINS OVER THE NEXT FEW HOURS. SFC DEWPOINTS
IN THE 40S F AND SFC TEMPS IN THE 60S F HAVE CONTRIBUTED TO SBCAPE
VALUES AROUND 1000 J/KG. 0-6 KM SHEAR VALUES OF 50 KT ARE EXPECTED
TO INCREASE OVER THE NEXT FEW HOURS BASED ON FORECAST SOUNDINGS.
THIS COUPLED WITH SHARPLY VEERING WIND PROFILES WITH HEIGHT HAVE
RESULTED IN AN ENVIRONMENT FAVORABLE FOR HIGH-BASED SUPERCELLS IN
THE VICINITY OF THE DENVER CYCLONE. IF A SUPERCELL CAN DEVELOP LATER
THIS AFTERNOON...STEEP MID-LEVEL LAPSE RATES AND STRONG DEEP LAYER
SHEAR SUGGEST LARGE HAIL...DAMAGING WIND GUSTS OR ISOLATED WEAK
TORNADOES WILL BE POSSIBLE. WW MAY BE NECESSARY ACROSS NERN CO
WITHIN THE NEXT 1 TO 2 HOURS.


..BROYLES.. 04/28/2003

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

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

39160494 39620541 40430542 40750531 40840484 40720410
40270380 39770382 39310387 39090418

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 28, 4:23 PM MDT	Mesoscale Discussion	SPC	Baca, Bent, Crowley, Kiowa, Prowers	3 hr

Nearby

Mesoscale Discussions in Colorado, 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.