A broken line of thunderstorms developed along a pre-frontal trough during the afternoon and early evening hours. A storm over northwest Sherman County produced straight-line winds strong enough to break four inch diameter tree limbs.
Every event with a place to put it. Tap one for its entry below.
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.
A broken line of thunderstorms developed along a pre-frontal trough during the afternoon and early evening hours. A storm over northwest Sherman County produced straight-line winds strong enough to break four inch diameter tree limbs.
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 Sep 19, 4:07 PM MST, 46 minutes earlier.
Area Forecast Discussion National Weather Service Goodland KS 507 PM MDT Wed Sep 19 2018 .SHORT TERM...(This evening through Thursday night) Issued at 302 PM MDT Wed Sep 19 2018 Main concern will be the thunderstorm forecast through this period. Prefrontal trough and cold front have stalled over the the northwest portion of the area. Per high resolution/Cam guidance, these boundaries will remained stalled or even slowly drift back a little west. This same guidance however differs on the spatial and temporal resolution of the development. Initially it does look like development will be on the prefrontal trough and will be aided by a shortwave trough moving on top of it and a right rear quadrant. A secondary area of development looks to be over northeast Colorado in the upslope area behind the front. This will have a little more help from the jet. Using those features and where the guidance overlaps, the north central and northwest portion of the area look to have the best chance of thunderstorms. These storms will move northeast through the evening. During the evening, considering the instability, shear, and lapse rates, there looks to be a risk for severe thunderstorms, and the Spc marginal risk has a good depiction of that. The biggest threat will be large hail but cannot rule out damaging winds. Precipitable water values are near 1.5 inches with flow parallel the front. So could get some training of cells and locally heavy rainfall. The surface boundaries will steadily move east and south during the last half of the night as another shortwave trough begins to move in from the west. So even after the initial round of storms move through, expect lingering storm or new development from the west. This lingering convection will continue through the morning. In the afternoon on Thursday, there should be rather significant and explosive development ahead of the boundaries, which are real slow to move through. This development will be aided another shortwave trough. So the highest pops will be over the southeast half of the area. This area again is under a marginal risk and that looks good. A bigger threat will be locally heavy rainfall and will have to watch closely. At this time the heaviest rainfall looks to be east of our area. Of note, if the boundaries slow down/are further west, the higher precipitation chances and threat for severe weather/heavy rainfall will have to be pulled back to the west. Of minor note, temperatures look to be 10 to 15 degrees cooler due to the cloud cover, precipitation, and cold front moving through. .LONG TERM...(Friday through Wednesday) Issued at 249 PM MDT Wed Sep 19 2018 Friday-Friday Night: An H5 shortwave moving ashore British Columbia this afternoon will dig ESE into the Dakotas early Friday morning and phase with a separate shortwave lifting northeast from the Great Basin into the Northern Plains -- with the ensuing wave progressing rapidly E/ENE into the Great Lakes. Subsidence /pressure rises/ in the wake of this feature will propel a drier airmass southward from the Dakotas into the Central Plains -- which will advect into the Tri-State area from the NE/E during the day. Lingering low-level moisture and SSE/SE upslope flow in the immediate lee of the Rockies may support convection along the Palmer Divide during the day Friday. However, convection is expected to remain just south/west of Cheyenne/Kit Carson counties and activity is likely to progress west toward the Front Range during the late afternoon and evening. Expect highs in the lower to mid 70s, and lows Friday night in the upper 40s. Saturday-Sunday Night: The Tri-State area will be situated along the southern periphery of the westerlies this weekend, with persistent southerly low-level flow on the eastern periphery of a diurnally waxing/waning lee cyclone. However, low-level moisture return is progged to be blocked by a cut-off upper low /attendant sfc low/ in Texas. As a result, dry conditions are expected to prevail. With southerly flow, expect a gradual warming trend Sat/Sun. Monday-Wednesday: An increasingly meridional synoptic pattern -- characterized by ridging along the Pacific/Atlantic coasts and troughing over the central CONUS -- is expected to evolve early next week, suggesting near or below normal temperatures and above normal chances for precipitation. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 507 PM MDT Wed Sep 19 2018 A meandering frontal boundary over portions of northeast Colorado and southwest Nebraska will allow for mainly VFR conditions thru 12z Thursday. VCTS thru 05z possible...especially for KMCK due to proximity to the front. MVFR ceilings from OVC015-025 for both sites from 12z-15z...with VFR conditions thereafter. Winds for KGLD...south 15-25kts thru 05z Thursday...becoming north northwest 10-15kts. By 15z...light/variable becoming west southwest 5-10kts by 20z. Winds for KMCK...south 15-25kts thru 05z Thursday then dropping down to 10kts. By 12z...west northwest around 10kts. LLWS 05z-12z 200@45kts. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && SHORT TERM...BULLER LONG TERM...VINCENT AVIATION...JN
Hazardous Weather Outlook National Weather Service Goodland KS 1044 AM MDT Wed Sep 19 2018 COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-201200- Yuma County-Kit Carson County-Cheyenne County-Cheyenne-Rawlins- Decatur-Norton-Sherman-Thomas-Sheridan-Graham-Wallace-Logan-Gove- Greeley-Wichita-Dundy-Hitchcock-Red Willow- 1044 AM MDT Wed Sep 19 2018 /1144 AM CDT Wed Sep 19 2018/ This hazardous weather outlook is for extreme southwest Nebraska... northwest Kansas and east central Colorado. .DAY ONE...THIS AFTERNOON AND TONIGHT... Scattered showers and thunderstorms are expected later this afternoon through the evening hours. A few of these storms could become severe with large hail, damaging winds, and locally heavy rainfall the main threats. The area with the greatest threat for severe weather will be along and west of a line from Burlington to Bird City to McCook. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH WEDNESDAY... No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required later this afternoon through the evening hours.
The Goodland radar (KGLD), 26 km away, was scanning. The volume nearest the first event began at 23:52 UTC.
1 thunderstorm wind. Local standard time, as filed.
Branches up to four inches in diameter were broke off of the trees. Pea size hail accompanied the thunderstorm winds.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Kansas in 2018Every state in 2018This day in weather historyWarnings in Kansas, September 2018
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: 784953.