Alert archive / Colorado / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 23, NWS Grand Junction, CO

July 17, 2000Moffat County, Colorado

NWS Grand Junction, CO issued this severe thunderstorm warning at Jul 17, 2000, 5:13 PM MDT for Moffat County, Colorado. It was in force for 47 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Jul 17, 2000, 5:13 PM MDT (23:13 UTC)
Expired: Jul 17, 2000, 6:00 PM MDT
In force: 47 min
Issued by: NWS Grand Junction, CO
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Moffat County, CO

The radar

The Grand Junction radar (KGJX), 173 km from the middle of the area, began a volume at 23:12 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

Salt Lake City I, UT (KSLC), launched 12:00Z, 11.2 hours before the alert went out and 312 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: 851 J/kg
Mixed-layer CIN: -175 J/kg
Mixed-layer LCL: 1850 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 125 m²/s²
0-3 km storm-relative helicity: 159 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 4.5

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Grand Junction, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 17, 2:04 PM MDT, 3 hours 9 minutes earlier.

Area forecast discussion, Jul 17, 2:04 PM MDT, 3 hours 9 minutes before

WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
204 PM MDT MON JUL 17 2000

SHOWERS AND A FEW THUNDERSTORMS THIS MORNING CORRELATED WITH ETA
500-300 MB OMEGA AND 300-200 MB LYR POTENTIAL VORT LOBE...WHICH IS
MOVING OFF TO THE NE.  DRYLINE ON WVPR STLT CROSSING FORECAST AREA
(FA) THIS AFTERNOON WITH WITH A FEW GOOD TSTMS AHEAD OF IT AND THEN
RATHER SHARP DRYING AND APPARENT LOSS OF LIFT BEHIND IT. A FEW STORMS
OVER THE WASATCH AND ABAJO MTNS AT 20Z IN DRIER AREA...BUT NOT MUCH
ON VIS STLT ATTM. HOWEVER...CAPE AND THETA-E GRADIENT PROGGED OVER FA
AT 00Z TUE...AND MAY BE ENOUGH SUNSHINE THIS AFTERNOON FOR TSTMS TO
OVERCOME SUBSIDENCE...SO HESITATE TO PULL TSTMS FROM CURRENT FORECAST
BUT WILL GO WITH QUICK END TO ACTIVITY IN MOST AREAS THIS EVENING
WITH LOSS OF HEATING. VORT CENTER OVER SRN CA THIS MORNING PROGGED
INTO NW AND N UTAH TONIGHT KEEPING MOST LIFT TO OUR NORTHWEST. NOT
SURE IF MODELS HAVE GOOD HANDLE ON VORT CTRS...THOUGH...AND WILL KEEP
A BIT MORE CLOUDS NORTH TONIGHT. MOISTURE PLUME MOVING INTO BAJA/SRN
CA/WRN AZ MAINLY HIGH LEVEL.

FOR TUESDAY AND WEDNESDAY...THE RIDGE CENTER ESTABLISHES ITSELF
OVER NM AND TX WITH DRIER SW FLOW ACROSS EASTERN UTAH AND WESTERN
COLORADO. COOLER AIR ALOFT AND WEAK JET PROGGED ACROSS MUCH OF THE
NORTHERN ZONES TUESDAY WEAKENS MORE BY WEDNESDAY. RIPPLES IN FLOW AND
DIFFERENTIAL HEATING SHOULD BE ENOUGH FOR SLIGHT CHANCE OF
AFTERNOON/EVENING SHOWERS AND TSTMS IN RESIDUAL MOISTURE FOR
TUESDAY...AND WILL KEEP SOME MENTION IN THE MOUNTAINS FOR WEDNESDAY.

IN THE EXTENDED...BROAD FLAT RIDGE FORECAST ALONG THE SOUTHERN-TIER
STATES WILL FAVOR A DRIER W-SW FLOW ACROSS EASTERN UTAH AND WESTERN
COLORADO.  WILL KEEP CURRENT WORDING OF SLIGHT CHANCE OF
AFTERNOON/EVENING THUNDERSTORMS OVER THE MOUNTAINS MAINLY FROM
DIFFERENTIAL HEATING.  RIDGE EXPECTED TO REBOUND THIS WEEKEND THAT
COULD FORETELL `THE NEXT MONSOONAL SURGE OF MOISTURE INTO THE AREA
SUNDAY AND EARLY NEXT WEEK.

.GJT...NONE.

JAD

The office that day

Everything else NWS Grand Junction, CO issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 2:11 PM MDT	Severe Thunderstorm Warning	GJT	Ouray	34 min
Jul 17, 3:50 PM MDT	Severe Thunderstorm Warning	GJT	Montrose, San Miguel	40 min
Jul 17, 4:17 PM MDT	Severe Thunderstorm Warning	GJT	Daggett	43 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.