Alert archive / Colorado / Severe Thunderstorm Warnings in 2001
Severe Thunderstorm Warning 25, NWS Grand Junction, CO
NWS Grand Junction, CO issued this severe thunderstorm warning at Sep 13, 2001, 2:15 PM MDT for Mesa County, Colorado. It was in force for 45 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Sep 13, 2001, 2:15 PM MDT (20:15 UTC)
- Expired
- Sep 13, 2001, 3:00 PM MDT
- In force
- 45 min
- Issued by
- NWS Grand Junction, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
County Mesa County, CO
The radar
The Grand Junction radar (KGJX), 22 km from the middle of the area, began a volume at 20:16 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.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 13, 2:30 PM MDT | Thunderstorm Wind 52 E | Fruita, CO |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Grand Junction, CO (KGJT), launched 12:00Z, 8.3 hours before the alert went out and 13 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
- 7 J/kg
- Mixed-layer CIN
- -121 J/kg
- Mixed-layer LCL
- 2564 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 66 m²/s²
- 0-3 km storm-relative helicity
- 64 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
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 Sep 13, 3:15 AM MDT, 11 hours earlier.
Area forecast discussion, Sep 13, 3:15 AM MDT, 11 hours before
WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 315 AM MDT THU SEP 13 2001 LEADING SHORT WAVE IN ADVANCE OF NORTHERN CALIFORNIA/WESTERN NEVADA CLOSED LOW HAS REACHED THE WESTERN EDGE OF FORECAST AREA BY 08Z. SCATTERED SHOWERS AND ISOLATED THUNDERSTORMS ALONG A LINE FROM NATURAL BRIDGES NATIONAL MONUMENT TO GREEN RIVER. DEEP SOUTHERLY FLOW AHEAD OF SHORT WAVE WILL INCREASE SUBTROPICAL MOISTURE THIS MORNING (PRECIPITABLE WATER FROM 00Z TUCSON SOUNDING WAS 1.5 INCHES).. ESPECIALLY THE SOUTHERN ZONES WHERE THE MOISTURE PLUME CONTAINS MOISTURE FROM TROPICAL STORM IVO. ETA/AVN SHOW DEEP MOISTURE REACHING THE SOUTHERN ZONES WITH ELEVATED INSTABILITY. WIND FIELDS ALSO SHOW SOME WIND SHEAR THROUGH THE MID LEVELS.. SUGGESTING ISOLATED CELLS WILL HAVE SOME ORGANIZATION. EXTENSIVE CLOUD COVER MAY LIMIT CONVECTIVE POTENTIAL FOR STRONG THUNDERSTORMS.. BUT LOCALLY HEAVY RAIN SHOWERS A DEFINITE POSSIBILITY AROUND THE FOUR CORNER AREAS AND THE SOUTH FACING SLOPES OF THE SAN JUANS AND UTAH/S SOUTHEAST MOUNTAINS. FARTHER NORTH.. SLIGHTLY BETTER DYNAMICS WILL BE AVAILABLE DUE TO PROXIMITY OF JET ENERGY ALOFT.. AND THIS WILL OFFSET LESS AVAILABLE MOISTURE. GUIDANCE DATA GAVE LIKELY POPS FOR ENTIRE AREA.. THIS SEEMS A LITTLE OVERDONE FOR SOME LOWER VALLEYS BUT REASONABLE FOR THE SOUTHERN ZONES. CLOSED LOW WEAKENS AND EJECTS NORTHEAST TO MONTANA ON FRIDAY. DRIER SUBSIDENT WESTERLY FLOW SHUNTS MOISTURE PLUME SOUTH OF THE COLORADO/NEW MEXICO BORDER. BUT RESIDUAL MOISTURE CONFINED IN THE LOWER LEVELS OVER COLORADO WILL ALLOW FOR SOME MOUNTAIN CONVECTIVE ACTIVITY IN THE AFTERNOON. UTAH WILL BE DRIER AND MORE STABLE DUE TO SUBSIDENT INVERSION AROUND 500 MB. FRISBIE SOUTHWESTERN COLORADO AND SOUTHEASTERN UTAH EMERGENCY MANAGERS SHOULD MAINTAIN A HIGH LEVEL OF WEATHER AWARENESS THROUGH THE EVENING DUE TO LOCALLY HEAVY RAIN SHOWERS...OTHERWISE NORMAL WEATHER AWARENESS NEEDED. .GJT...NONE.
The office that day
Everything else NWS Grand Junction, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 13, 1:43 PM MDT | Flash Flood Warning | GJT | Mesa | 3 hr |
| Sep 13, 12:20 PM MDT | Severe Thunderstorm Warning | GJT | Grand | 55 min |
Nearby
Severe Thunderstorm Warnings in Colorado, 2001Every severe thunderstorm warning in 2001
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.