Alert archive / Colorado / Severe Thunderstorm Warnings in 1999
Severe Thunderstorm Warning 102, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at Jul 24, 1999, 7:20 PM MDT for Logan County, Morgan County, Washington County, Colorado. It was in force for 30 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 24, 1999, 7:20 PM MDT (01:20 UTC)
- Expired
- Jul 24, 1999, 7:50 PM MDT
- In force
- 30 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties; the outline is the Mesonet’s reconstruction
Counties Logan County, CO, Morgan County, CO, Washington County, CO
The radar
The Denver radar (KFTG), 116 km from the middle of the area, began a volume at 01:20 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, 1.3 hours before the alert went out and 51 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
- 31 J/kg
- Mixed-layer CIN
- -196 J/kg
- Mixed-layer LCL
- 2303 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 23 m²/s²
- 0-3 km storm-relative helicity
- 99 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 Denver/Boulder, CO wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 24, 2:22 PM MDT, 4 hours 58 minutes earlier.
Area forecast discussion, Jul 24, 2:22 PM MDT, 4 hours 58 minutes before
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE DENVER COLORADO 222 PM MDT SAT JUL 24 1999 MONSOON MSTR HAS SHIFTED FURTHER N THIS AFTN AND COMBINED WITH INCRG LOW LVL MSTR HAS ALLOWED FOR WDLY SCT TSRA TO DVLP OVR AREA. STLT SHOWS APPARENT BNDRY NE OF DIA EXTENDING SE TO LIC. WDLY SCT TSRA ARE DVLPG ALONG THIS BNDRY AND SHOULD CONT THRU THE EVENING HRS. TSRA OVR MTNS MAY SEND OUT AN OUTFLOW BNDRY WHICH MAY ALLOW FOR ADDITIONAL DEVELOPMENT ALONG THE FNT RANGE IN THE NEXT FEW HOURS. LATEST VWP SHOWS SLY WNDS AVERAGING AROUND 20 KTS FM THE SFC TO 12 KFT SO STORMS WL BE MOVING WHICH SHOULD LIMIT HEAVY RAIN POTENTIAL. ON SUNDAY WK BNDRY WL MOVE INTO RGN FM THE NW AND MAY ALLOW FOR SOME SCOURING OUT OF LOW LVL MSTR IN AND NR THE FOOTHILLS AS LOW LVL FLOW BECOMES MORE WNW. EXACT POSITION OF THIS BNDRY BY SAT AFTN WL IMPACT TSRA CHCS OVR NERN PLAINS. AT THIS POINT WL PUT SLIGHTLY HIGHER POPS EAST OF A STERLING-AKO-LIC LN ALONG EXPECTED POSITION OF BNDRY BY AFTN. MEANWHILE INFLUX OF MONSOON MSTR WL CONT OVR NRN CO WHICH SHOULD ALLOW FOR WDLY SCT TSRA OVR THE MTNS BY AFTN. A FEW THESE STORMS MAY DRIFT INTO THE FOOTHILLS AND FNT RANGE BY LATE AFTN AND EVENING AS MID-LVL FLOW IS FCST TO BECOME MORE WLY. BY SUN NGT AND MON MODELS BRING ANOTHER BNDRY INTO NERN CO BY MON MRNG. ELY LOW LVL FLOW IS FCST TO INCR DURING THE DAY ON MON WHICH MAY ALLOW FOR DEEPER LOW LVL MSTR TO MOVE INTO FOOTHILLS BY AFTN. WITH A CONTINUATION OF MONSOON MSTR ACRS RGN SHOULD SEE MORE WDLY SCT-SCT TSRA OVR THE MTNS MON AFTN. IN ADDITION POTENTIAL FOR HEAVY RAIN PRODUCING STORMS MAY INCR IN THE FOOTHILLS AND FNT RANGE IF FORECASTED MOIST ELY LOW LVL FLOW MATERIALIZES AND MID-LVL FLOW WKNS AS PROGGED. IN EXTENDED PD UPR LVL HI WL REMAIN ENTRENCHED ACRS RGN. IF MONSOON MSTR FETCH CONTS THEN SHOULD SEE AT LEAST WDLY SCT TSRA EACH AFTN AND EVENING IN THE MTNS. OVR LOWER ELEVATIONS APPEARS ENOUGH LOW LVL MSTR WL LINGER ON TUE FOR ANOTHER CHC OF TSRA. KLEYLA .DEN...NONE.
The office that day
Everything else NWS Denver/Boulder, CO issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 24, 6:18 PM MDT | Severe Thunderstorm Warning | BOU | Logan, Morgan, Weld | 42 min |
| Jul 24, 6:40 PM MDT | Tornado Warning | BOU | Morgan | 30 min |
Nearby
Severe Thunderstorm Warnings in Colorado, 1999Every severe thunderstorm warning in 1999
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.