Isolated thunderstorms developed along the CO/KS border which traveled southeast during the afternoon hours. The thunderstorms yielded hail up to ping pong ball sized as well as a 64 mph wind gust due to a heat burst event.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GLD wrote it up.
Isolated thunderstorms developed along the CO/KS border which traveled southeast during the afternoon hours. The thunderstorms yielded hail up to ping pong ball sized as well as a 64 mph wind gust due to a heat burst event.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Goodland, KS wrote its last area forecast discussion before the first event at Aug 13, 1:33 PM CST, 2 hours 12 minutes earlier.
Area Forecast Discussion National Weather Service Goodland KS 133 PM MDT Thu Aug 13 2020 .SHORT TERM...(This evening through Sunday) Issued at 110 PM MDT Thu Aug 13 2020 Tonight...Isolated to scattered thunderstorms are expected to initiate along the CO/KS border around 2 PM MDT with a general motion to the east through about sunset before dissipating early this evening. All modes of severe weather will be possible. Fog is expected to redevelop a few hours before sunrise, primarily along and east of the CO/KS border. Low temperatures are expected to be in the low to mid 60s. Friday-Friday night...fog is expected for a few hours after sunrise, mainly east of the CO/KS border. A cold front enters the northwest portion of the area in the morning steadily moving through the remainder of the area through the rest of the day. Thunderstorms will be possible in the afternoon and evening generally east of a line from Trenton to Goodland and Sharon Springs. High temperatures are expected to reach the low to mid 90s. Low temperatures range from the upper 50s to low 60s. Saturday-Saturday night...some discrepancies develop with the handling of the possibility of showers and thunderstorms moving through the area under northwest flow aloft. Models are showing pretty meager moisture in the 700-500mb layer, especially during the night which is when the current forecast has high chance pops for precipitation. Even the 850-700mb layer isnt overly impressive during the afternoon. I'm sure things will change so no changes made at this time. It does look to be cooler behind Fridays cold front with high temperatures in the mid 80s. Low temperatures fall into the mid 50s to around 60. Sunday...we'll have another chance for thunderstorms under northwest flow aloft. High temperatures range from the mid 80s to around 90. .LONG TERM...(Sunday night through Wednesday Night) Issued at 132 PM MDT Thu Aug 13 2020 Sunday night will see storms linger throughout the overnight hours. However, the higher chances appear to be further south and east and diminish overnight. Lows will likely be near 60 but could be a bit warmer depending on how long the cloud cover and storms will last. For next week, not much has changed with the upper level pattern. An upper high with associated ridge will remain camped out in the Western CONUS with a trough digging down into the Eastern CONUS. This leaves the Tri-State area with north to northwest flow aloft which will allow some shortwaves to move through the area and provide some instability. Meanwhile at the surface, the stationary front in Colorado lives up to its name and does not really move from its spot just west of the Colorado border. Combine this with decently high PWAT values and sufficient lower level moisture and we get diurnally driven storms for most of next week. Storms will fire off of the stationary front or Front Range, move east, and dissipate in the evening and early night hours. The individual setup for each day will cause variations in initiation and storm strength but each day could have the potential for some severe storms and heavy rainfall. Worth noting is that the stationary front may oscillate along the KS/CO Wednesday before returning to its original position. This may lower precip chances as the front moves into higher surface pressure that will have moved in during the early week for the Central and Eastern Plains. Temperatures look to be near stable with highs in the mid to upper 80's for the beginning of the week. The GFS is suggesting some warmer temperatures by a few degrees but staying with current range for now. && .AVIATION...(For the 18Z TAFS through 18Z Friday afternoon) Issued at 1110 AM MDT Thu Aug 13 2020 KGLD, vfr conditions expected through the period. Winds this afternoon generally variable at 6kts perhaps becoming east to southeast at speeds around 10kts. Thunderstorms will be possible at the terminal in the 20z-22z timeframe, primary hazard is wind gusts that could reach 50kts. Locally heavy rainfall could produce visibility reductions. For tonight southeast winds near 10kts slowly veer to the southwest at similar speeds by sunrise. Will have to watch for the possibility of sub vfr cig/vs around sunrise in fog, right now it appears sub vfr conditions will be east of the terminal. For Friday winds shift to the northwest near 10kts at the end of the period as a cold front starts to move through. KMCK, sub vfr cigs expected from taf issuance through about 20z before vfr conditions return through 08z. Thunderstorms possible in the 23z-01z timeframe with wind gusts to 50kts primary hazard. Winds generally from the southeast near 11kts. From 09z-14z sub vfr cigs/vis expected in stratus and fog with winds light and variable. After 15z vfr conditions expected with winds become southerly under 10kts. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && SHORT TERM...99 LONG TERM...KAK AVIATION...99
Hazardous Weather Outlook National Weather Service Goodland KS 1030 AM MDT Thu Aug 13 2020 COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-141200- Yuma County-Kit Carson County-Cheyenne County-Cheyenne-Rawlins- Decatur-Norton-Sherman-Thomas-Sheridan-Graham-Wallace-Logan-Gove- Greeley-Wichita-Dundy-Hitchcock-Red Willow- 1030 AM MDT Thu Aug 13 2020 /1130 AM CDT Thu Aug 13 2020/ This hazardous weather outlook is for extreme southwest Nebraska... northwest Kansas and east central Colorado. .DAY ONE...THIS AFTERNOON AND TONIGHT... Severe thunderstorms are possible from 2 PM MDT (3 PM CDT) through 8 PM MDT (9 PM CDT) east of a line from Wray to Cheyenne Wells Colorado. The primary hazards will be hail up to the size of golf balls, wind gusts to 70 mph, and perhaps a brief tornado. Fog is expected to develop a few hours before sunrise Friday morning generally east of the Colorado Kansas border. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH THURSDAY... Fog is expected for a few hours after sunrise Friday morning generally east of the Colorado Kansas border. There is a marginal risk of severe thunderstorms Friday afternoon and evening, along and east of a McCook to Goodland to Cheyenne Wells line. large hail and damaging winds will be possible near stronger storms. A few strong to severe storms will be possible once again Saturday afternoon and evening. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated at this time.
Special Weather Statement
National Weather Service Goodland KS
250 PM CDT Thu Aug 13 2020
KSZ001-132015-
Cheyenne KS-
250 PM CDT Thu Aug 13 2020
...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN CHEYENNE COUNTY IN
NORTHWESTERN KANSAS UNTIL 315 PM CDT...
At 249 PM CDT, Doppler radar was tracking a strong thunderstorm 12
miles southwest of St. Francis, moving southeast at 10 mph.
Nickel size hail and winds in excess of 30 mph will be possible with
this storm.
This storm will remain over mainly rural areas of southwestern
Cheyenne County in northwestern Kansas.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
This storm may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.
&&
LAT...LON 3960 10177 3957 10186 3957 10194 3962 10203
3967 10192
TIME...MOT...LOC 1949Z 297DEG 7KT 3962 10193
DDTSpecial Weather Statement National Weather Service Goodland KS 243 PM MDT Thu Aug 13 2020 COZ091-132100- Kit Carson County CO- 243 PM MDT Thu Aug 13 2020 ...SIGNIFICANT WEATHER ADVISORY FOR EAST CENTRAL KIT CARSON COUNTY UNTIL 300 PM MDT... At 242 PM MDT, Doppler radar was tracking a strong thunderstorm over Burlington, moving east at 30 mph. Nickel size hail and winds in excess of 40 mph will be possible with this storm. Locations impacted include... Burlington and Bethune. This includes the following highways... Interstate 70 in Colorado between mile markers 430 and 448. Highway 385 between mile markers 184 and 192. PRECAUTIONARY/PREPAREDNESS ACTIONS... This storm may intensify, so be certain to monitor local radio stations and available television stations for additional information and possible warnings from the National Weather Service. && LAT...LON 3928 10243 3937 10242 3935 10207 3922 10210 TIME...MOT...LOC 2042Z 280DEG 28KT 3932 10230 DDT
The Goodland radar (KGLD), 56 km away, was scanning. The volume nearest the first event began at 22:03 UTC.
6 hail, 1 high wind. Local standard time, as filed.
Mesonet station reported a 64 mph highwind gust. This is a heat burst event as relative humidity dropped from 66% to 17% and temperature increased briefly to 91 F from 83 F at time of wind gust.
Nickel sized hail reported at location.
Quarter sized hail reported at location. Time is radar estimated.
Pea to nickel sized hail reported at location. Hail was ongoing with approximately 40% of the ground covered.
Half dollar sized hail with a few ping pong ball sized hailstones reported at location.
Penny to ping pong ball sized hail reported at location. Time is radar estimated.
Nickel sized hail reported at location.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kansas in 2020Every state in 2020This day in weather historyWarnings in Kansas, August 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 918814, 917575, 917576, 917911, 917912, 917914, 917913.