Thunderstorms initiated along a dry line in central Colorado moving east and forming a cluster of supercells that developed into a line as it moved through northwest Kansas. The storms produced up to golf ball sized hail and wind gusts near 70 mph that produced brown out conditions and snapped numerous tree limbs in Logan, Thomas, Gove, and Sheridan counties.
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.
Thunderstorms initiated along a dry line in central Colorado moving east and forming a cluster of supercells that developed into a line as it moved through northwest Kansas. The storms produced up to golf ball sized hail and wind gusts near 70 mph that produced brown out conditions and snapped numerous tree limbs in Logan, Thomas, Gove, and Sheridan counties.
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 Jul 12, 5:25 PM CST, 2 hours 5 minutes earlier.
Area Forecast Discussion National Weather Service Goodland KS 525 PM MDT Sun Jul 12 2020 .UPDATE... Issued at 520 PM MDT Sun Jul 12 2020 Based on current radar trends, increased pops in northern and eastern areas. Also expanded the Severe Thunderstorm Watch one column of counties eastward. && .SHORT TERM...(This evening through Monday night) Issued at 143 PM MDT Sun Jul 12 2020 Across the region this afternoon, skies are mainly sunny with some scattered low/high cloud portions of the area. Temperatures are ranging from the mid 80s into the mid 90s, with an area-wide southerly gradient gusting to 30-40 mph at times. For the remainder of the afternoon hrs into tonight, the focus will be just west of the CWA in central Colorado, where convection is expected to initiate along a dryline then shift east with the arrival of a shortwave, then shift SE later tonight as the convection works over the northern periphery of the strong h5 ridge over the southern portion of the country. SPC mesoanalysis has Dcape values 1300-1700 from the Colorado border west, 40-45kts of bulk shear, and decent mid level lapse rates should allow for strong to severe storms to develop. Large hail parameter does indicate large than 1 inch possible. Severe Thunderstorm Watch will probably be issued for portions of the area later this afternoon, with wind and hail highlights. Precipitation that does shift over the CWA will taper by 06z Monday, allowing for dry conditions thru sunrise Monday and a portion of the morning hours. This will lead into Monday/Monday night where a stronger shortwave moves over the region, triggering a potential stronger round of storms. SPC has highlighted most of the CWA in Slight Risk for wind/hail threats, but last outlook update has the enhanced portion sliding further south, which may change later tonight for portions of the CWA. With the potential for more widespread areal coverage of storms, have increased pops slightly, but still in the chance category due to timing into the CWA. For temps, mid to upper 90s for Monday highs, with 60s for lows tonight and Monday night. .LONG TERM...(Monday night through Sunday) Issued at 143 PM MDT Sun Jul 12 2020 This this period of the forecast the long wave trough continues to reside over the central CONUS, flattening the ridge. The resulting zonal flow over the forecast area will allow an upper level short wave trough to move through each afternoon and evening. The GEFS members show a higher high probability of rainfall occurring Tuesday and Wednesday over the Southeast Colorado extending into the southwest part of the forecast area. The dry line will move east of the forecast area Thursday, through the rest of the period. This lowers confidence of storms occurring due to drier air present behind the dry line, despite the aid of the upper level short wave troughs moving through. Am thinking the best chance for any severe thunderstorms will be Tuesday and Wednesday afternoon and evenings before the dry line is pushed east. The cold front still looks to move through Tuesday, lingering into Wednesday. This may also serve as a focus for storm development Tuesday afternoon over the southwestern part of the forecast area. The hot air mass will return Thursday as the cooler air mass is pushed east of the forecast area. Friday and Saturday relative humidity values will fall close to 15% for the northwest part of the forecast area. Winds are forecast to remain below 25 MPH at this time for that part of the forecast area. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 520 PM MDT Sun Jul 12 2020 Main aviation concern will be chance of thunderstorms early this evening. Based on radar trends, KGLD stands the best chance of being impacted, but storms are moving eastward so will continue to monitor for KMCK. After about 03z, storms should be moving south of the area, with VFR expected at both terminals through the remainder of the TAF period. && .GLD WATCHES/WARNINGS/ADVISORIES... KS...NONE. CO...NONE. NE...NONE. && UPDATE...024 SHORT TERM...JN LONG TERM...JTL AVIATION...024
Hazardous Weather Outlook National Weather Service Goodland KS 216 PM MDT Sun Jul 12 2020 COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-132015- Yuma County-Kit Carson County-Cheyenne County-Cheyenne-Rawlins- Decatur-Norton-Sherman-Thomas-Sheridan-Graham-Wallace-Logan-Gove- Greeley-Wichita-Dundy-Hitchcock-Red Willow- 216 PM MDT Sun Jul 12 2020 /316 PM CDT Sun Jul 12 2020/ This hazardous weather outlook is for extreme southwest Nebraska... northwest Kansas and east central Colorado. .DAY ONE...THIS AFTERNOON AND TONIGHT... A Severe Thunderstorm Watch is in effect for northeast Colorado and adjacent Kansas counties until 900 PM MDT. Marginal and Slight Risk areas for severe thunderstorms are issued for areas mainly along and west of Highway 25. The main area of focus will be in northeast Colorado and adjacent Kansas counties south of Interstate 70. Threats for severe storms to develop will be around 3-9 pm MDT. Main possible weather threats will be wind gusts to 70 mph and hail up to 1 to 2 inches. .DAYS TWO THROUGH SEVEN...MONDAY THROUGH SUNDAY... There is a Slight Risk for severe storms on Monday July 13th. Thunderstorms developing along the Front Range of the Rockies in Colorado and Wyoming may grow upscale and develop into a squall line capable of producing widespread damaging winds late Monday afternoon and evening. .SPOTTER INFORMATION STATEMENT... Spotter activation may be required.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GOODLAND KS
708 PM MDT SUN JUL 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0537 PM TSTM WND DMG 7 NNW MAX 40.20N 101.46W
07/12/2020 DUNDY NE PUBLIC
MATURE PINE TREE WAS BLOWN OVER. ESTIMATED
TIME OF REPORT FROM RADAR.
&&Special Weather Statement National Weather Service Goodland KS 816 PM CDT Sun Jul 12 2020 KSZ028-130130- Logan KS- 816 PM CDT Sun Jul 12 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHERN LOGAN COUNTY UNTIL 830 PM CDT... At 816 PM CDT, Doppler radar was tracking a strong thunderstorm 4 miles west of Russell Springs, or 23 miles northwest of Scott State Lake, moving southeast at 50 mph. Penny size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Russell Springs. PRECAUTIONARY/PREPAREDNESS ACTIONS... Torrential rainfall is also occurring with this storm, and may lead to localized flooding. Do not drive your vehicle through flooded roadways. && A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for west central Kansas. LAT...LON 3896 10140 3901 10102 3878 10082 3870 10141 TIME...MOT...LOC 0116Z 302DEG 44KT 3889 10126 JRM
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GOODLAND KS
725 PM MDT SUN JUL 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0530 PM TSTM WND DMG BENKELMAN 40.05N 101.53W
07/12/2020 DUNDY NE EMERGENCY MNGR
ATLEAST 2 POWER POLES LEANING FROM THE WIND,
6 INCH DIAMETER TREE LIMB BLOWN DOWN.
ESTIMATED TIME OF REPORT FROM RADAR.
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GOODLAND KS
727 PM MDT SUN JUL 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0630 PM TSTM WND DMG STRATTON 40.15N 101.23W
07/12/2020 HITCHCOCK NE EMERGENCY MNGR
POWER OUTAGE REPORTED IN STRATTON,
CULBERTSON, TRENTON, AND PALISADE.
&&Special Weather Statement National Weather Service Goodland KS 828 PM CDT Sun Jul 12 2020 KSZ014-130145- Thomas KS- 828 PM CDT Sun Jul 12 2020 ...SIGNIFICANT WEATHER ADVISORY FOR SOUTHEASTERN THOMAS COUNTY UNTIL 845 PM CDT... At 828 PM CDT, Doppler radar was tracking strong thunderstorms along a line extending from 3 miles southeast of Gem to 9 miles southeast of Colby. Movement was southeast at 20 mph. Penny size hail and winds in excess of 30 mph will be possible with these storms. Locations impacted include... Halford. This includes Interstate 70 in Kansas between mile markers 60 and 68. PRECAUTIONARY/PREPAREDNESS ACTIONS... These storms 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. && A Severe Thunderstorm Watch remains in effect until 1000 PM CDT for northwestern Kansas. LAT...LON 3933 10075 3919 10087 3934 10100 3942 10090 TIME...MOT...LOC 0128Z 324DEG 18KT 3939 10086 3929 10092 AW
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GOODLAND KS
729 PM MDT SUN JUL 12 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0656 PM HAIL MCCOOK 40.20N 100.62W
07/12/2020 E0.88 INCH RED WILLOW NE PUBLIC
ESTIMATED TIME OF REPORT FROM RADAR.
&&The Goodland radar (KGLD), 78 km away, was scanning. The volume nearest the first event began at 01:30 UTC.
4 thunderstorm wind, 3 hail. Local standard time, as filed.
Emergency manager reported several 2 inch live tree limbs and one 7 inch limb from a rotted tree down. Damage was caused by strong winds from an outflow boundary associated with a strong thunderstorm on the north side of I-70.
Several 2 inch in diameter tree limbs were blown down due to strong winds associated with a thunderstorm.
Emergency Manager reported patches of blowing dust with brown out conditions just north of Oakley due to the leading edge of an outflow boundary producing strong wind gusts.
A citizen reported dime to nickel sized hail.
A citizen reported hail between a nickel and quarter in size.
Emergency Manager reported hail ranging from quarters to golf ball in size covering the ground enough to appear white. At a nearby residence, hail ranging from quarters to golf ball in size broke several windows.
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, July 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: 909645, 909646, 909647, 909649, 909648, 909650, 909651.