Alert archive / Colorado / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 59, NWS Denver/Boulder, CO

July 12, 2000Logan County, Colorado

NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 12, 2000, 4:25 PM MDT for Logan County, Colorado. It was in force for 50 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Jul 12, 2000, 4:25 PM MDT (22:25 UTC)
Expired: Jul 12, 2000, 5:15 PM MDT
In force: 50 min
Issued by: NWS Denver/Boulder, CO
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Logan County, CO

The radar

The Cheyenne radar (KCYS), 133 km from the middle of the area, began a volume at 22:27 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 12, 2:15 PM MDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Denver, CO (KDNR), launched 12:00Z, 10.4 hours before the alert went out and 98 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: 40 J/kg
Mixed-layer CIN: -362 J/kg
Mixed-layer LCL: 1871 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -12 m²/s²
0-3 km storm-relative helicity: 14 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WUUS55 KBOU 122226
SVRDEN
COC075-122315-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
425 PM MDT WED JUL 12 2000

THE NATIONAL WEATHER SERVICE IN DENVER HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  CENTRAL LOGAN COUNTY IN NORTHEAST COLORADO

* UNTIL 515 PM MDT

* AT 425 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM 2 MILES SOUTHWEST OF NORTH STERLING
  RESERVOIR...OR ABOUT 8 MILES NORTHWEST OF STERLING...MOVING
  SOUTHWEST AT 5 MPH.

LOCATIONS IN THE WARNING INCLUDE...BUT ARE NOT LIMITED TO...PADRONI
AND NORTH STERLING RESERVOIR

HEAVY RAINS MAY FLOOD LOW LYING AREAS SUCH AS DITCHES AND
UNDERPASSES. AVOID THESE AREAS AND DO NOT CROSS FLOODED ROADS AS THEY
MAY BE WASHED OUT. WATER LEVELS OF SMALL STREAMS AND RIVERS MAY ALSO
RISE...THEREFORE SEEK HIGHER GROUND IF THREATENED BY FLOOD WATERS.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 55 MPH...
DESTRUCTIVE HAIL...DEADLY LIGHTNING...AND VERY HEAVY RAIN. FOR YOUR
PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME
OR BUSINESS. HEAVY RAINS FLOOD ROADS QUICKLY SO DO NOT DRIVE INTO
AREAS WHERE WATER COVERS THE ROAD.

LAT...LON 4075 10347 4060 10329 4077 10309 4086 10326

GARD...WFO BOULDER

The office that day

Everything else NWS Denver/Boulder, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 12, 2:48 PM MDT	Severe Thunderstorm Warning	BOU	Morgan, Washington	42 min
Jul 12, 2:52 PM MDT	Severe Thunderstorm Warning	BOU	Logan	53 min
Jul 12, 3:30 PM MDT	Flash Flood Warning	BOU	Morgan	90 min
Jul 12, 3:44 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	46 min
Jul 12, 3:46 PM MDT	Severe Thunderstorm Warning	BOU	Logan	44 min
Jul 12, 3:57 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	48 min
Jul 12, 4:13 PM MDT	Tornado Warning	BOU	Morgan	32 min
Jul 12, 4:43 PM MDT	Severe Thunderstorm Warning	BOU	Morgan	47 min
Jul 12, 4:48 PM MDT	Severe Thunderstorm Warning	BOU	Weld	42 min
Jul 12, 4:53 PM MDT	Tornado Warning	BOU	Morgan	37 min
Jul 12, 5:04 PM MDT	Flash Flood Warning	BOU	Morgan	3 hr
Jul 12, 5:13 PM MDT	Severe Thunderstorm Warning	BOU	Logan	47 min
Jul 12, 5:37 PM MDT	Severe Thunderstorm Warning	BOU	Weld	38 min

Nearby

Severe Thunderstorm Warnings in Colorado, 2000 Every severe thunderstorm warning in 2000

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.