Alert archive / Colorado / Severe Thunderstorm Warnings in 1987
Severe Thunderstorm Warning 4, NWS Denver/Boulder, CO
NWS Denver/Boulder, CO issued this severe thunderstorm warning at May 18, 1987, 7:03 PM MDT for Yuma County, Colorado. It was in force for 32 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
- May 18, 1987, 7:03 PM MDT (01:03 UTC)
- Expired
- May 18, 1987, 7:35 PM MDT
- In force
- 32 min
- Issued by
- NWS Denver/Boulder, CO
- Area
- Whole counties
County Yuma County, CO
The radar
The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.
What was reported inside it
| Time | Report | Where | Remark |
|---|---|---|---|
| May 18, 7:23 PM MDT | Hail 1 | Yuma, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.
The nearest sounding before it
Denver, CO (KDEN), launched 00:00Z, 1.1 hours before the alert went out and 70 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
- 3 J/kg
- Mixed-layer CIN
- -146 J/kg
- Mixed-layer LCL
- 2041 m above ground
- 0-6 km bulk shear
- 46 kt
- 0-1 km storm-relative helicity
- 132 m²/s²
- 0-3 km storm-relative helicity
- 242 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000
TTAA00 KDEN 190108
SVRDEN
COC125-190135-
BULLETIN...IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE DENVER CO
703 PM MDT MON MAY 18 1987
THE NATIONAL WEATHER SERVICE HAS ISSUED A SEVERE THUNDERSTORM
WARNING EFFECTIVE UNTIL 735 PM MDT FOR PEOPLE IN THE
FOLLOWING COUNTIES OF NORTHEAST COLORADO:
NORTHEAST YUMA
INCLUDING THE FOLLOWING TOWNS/CITIES:
WRAY LAIRD
AT 700 PM MDT RADAR INDICATED A SEVERE THUNDERSTORM ABOUT 60 MILES
SOUTHEAST OF STERLING OR 5 MILES NORTHWEST OF WRAY.
MOVEMENT WAS TO THE EAST SOUTHEAST AT 15 MILES AN HOUR.
REMEMBER..A SEVERE THUNDERSTORM CAN PRODUCE LARGE DAMAGING
HAIL..DAMAGING WINDS OF OVER 60 MPH..DEADLY LIGHTNING..AND
HEAVY RAINS THAT CAN QUICKLY FLOOD A LOW LYING AREA.
TO REPORT SEVERE WEATHER HAVE THE NEAREST LAW ENFORCEMENT
AGENCY RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE OFFICE
IN DENVER..OR CALL YOUR REPORT TO THE NATIONAL WEATHER SERVICE
AT 361-0663. DO NOT CALL THIS NUMBER FOR INFORMATION.
DULONG
LAT..LON 4043 10249 4042 10203 3997 10205 3997 10246What 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.
In the hours before
Special weather statement, May 18, 4:32 PM MDT, 2 hours 31 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 430 PM MDT MON MAY 18 1987 ...SHOWERS AND THUNDERSTORMS BECOMING NUMEROUS OVER WELD COUNTY IN NORTHEAST COLORADO... SHOWERS AND THUNDERSTORMS ARE BECOMING NUMEROUS OVER WELD COUNTY. A FEW OF THE THUNDERSTORMS HAVE BECOME HEAVY WITH LOCALLY HEAVY RAINFALL INDICATED. THIS ACTIVITY IS MOVING TO THE NORTHEAST AT 10 MPH AND IT LOOKS LIKE IT SHOULD CONTINUE TO INCREASE IN COVERAGE OVER WELD COUNTY AND MAY SPREAD INTO MORGAN COUNTY AS WELL DURING THE NEXT COUPLE OF HOURS. LOCALLY HEAVY RAINFALL..GUSTY WINDS AND SMALL HAIL MAY BE EXPECTED IN THESE AREAS. DULONG
Special weather statement, May 18, 6:22 PM MDT, 41 minutes before
SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE DENVER CO 620 PM MDT MON MAY 18 1987 ...GUSTY THUNDERSTORM WINDS IN MORGAN COUNTY OF NORTHEAST COLORADO... GUSTY WINDS..TRIGGERED BY A STRONG THUNDERSTORM..HAVE OCCURRED IN MORGAN COUNTY DURING THE PAST HOUR. GUSTS TO 45 MPH WERE RECORDED AT FORT MORGAN AT 6 PM MDT. GUSTY WINDS OF 30 TO 40 MPH WILL CONTINUE OVER MORGAN COUNTY AND FAN OUT INTO NORTHERN WASHINGTON COUNTY DURING THE NEXT 30 MINUTES BEFORE DYING OUT. DULONG
Nearby
Severe Thunderstorm Warnings in Colorado, 1987Every severe thunderstorm warning in 1987
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.