A thunderstorm produced damaging downburst winds which snapped a power pole. A weak short-lived landspout also touched down and tossed around some lawn furniture.
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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 BOU wrote it up.
A thunderstorm produced damaging downburst winds which snapped a power pole. A weak short-lived landspout also touched down and tossed around some lawn furniture.
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 Denver/Boulder, CO wrote its last area forecast discussion before the first event at Jun 5, 8:47 AM MST, 4 hours 45 minutes earlier.
Area Forecast Discussion National Weather Service Denver/Boulder CO 947 AM MDT Mon Jun 5 2017 .UPDATE... Issued at 947 AM MDT Mon Jun 5 2017 Convective development is already occurring this morning and ahead of schedule. This seems to be aided by mid level moisture plume pushing across the mountains. Have bumped up the PoPs a bit more for earlier arrival of convection and this mid level moisture plume. Otherwise forecast remains relatively unchanged with pulse storms, locally heavy rain due to slow movement, and isolated brief severe storms possible on the plains. Highest threat of those stronger storms would be just east of metro Denver where deeper low level moisture exists and CAPES should reach 1500 J/kg. && .SHORT TERM...(Today and tonight) Issued at 410 AM MDT Mon Jun 5 2017 An upper level ridge axis shifts over Colorado today as an upper level trough moves across the Northern Rockies. Mid and upper level moisture increases under the ridge across the area. Meanwhile, a southeast low level flow over the plains will transport low level moisture to eastern Colorado. Precipitable water values climb to a half inch to three-quarters of an inch over the higher terrain. For the Front Range and eastern plains, precipitable water values reach three-quarters of an inch to one inch. Higher values are expected over the eastern plains this evening. CAPE reaches 800 to 1500 J/kg over the plains, while values along the urban corridor and into the higher terrain will be less than 800 J/kg. Shear will be weak, so expect most of the activity to be pulse storms. May be a few brief severe storms on the plains with hail to one inch and 60 mph winds. Storms are expected to initially form over the higher terrain around or just after 18Z. The storms are expected to spread east during the afternoon and early evening as convergence along outflow boundaries produce new storms over the plains. As far as the forecast goes, high temperatures will be a few degrees warmer today. This will also help break the cap. The highest pops will be over the higher terrain and also over the eastern plains where better moisture will reside and better convergence will be. Thunderstorms will continue to track east across the area this evening and decrease late this evening as the airmass stabilizes. A cold front associated with the upper level trough over the Northern Rockies will drop south into Northern Colorado late tonight. This will increase low level moisture and bring cooler temperatures for Tuesday. .LONG TERM...(Tuesday through Sunday) Issued at 410 AM MDT Mon Jun 5 2017 Dirty upper level ridge with its axis aligned with the Rockies is forecast to remain nearly stationary through most of the week. Waves of moisture and mid-level instability rotating through this ridge will provide the needed ingredients to produce showers and thunderstorms Tuesday and Wednesday. On Tuesday, enhanced northeasterly upslope flow behind a cold front which models show sliding south across nern Colorado during the pre-dawn hours will provide the additional lift and low-level moisture for considerable cloud cover on the plains and the formation of scattered to numerous showers/t-storms mainly over and along the Front Range and Palmer Divide during the afternoon and evening hours. Models soundings at points near the foothills and on the Palmer Divide indicate precipitable water around an inch at 00z/Wed. The window for heaviest rainfall appears to be around that time when a shortwave in northwest flow aloft passes overhead. Don't see much more than a few hours of moderate to possibly heavy rainfall in this area. May also see some small hail from the stronger storms on the Palmer Divide, while the risk of flash flooding appears low. Farther out across the northeast plains, the cooler post- frontal airmass looks quite stable and therefore rain chances will be much lower out there. In the high country, notably areas west of the Continental Divide, storm chances will not be as great with drier air and a strong mid-level cap over the area. Most of this storm activity should wrap up by midnight, although could see a few storms lingering into the early morning hours across the southeast corner of the CWA. By Wednesday, the cooler airmass begins to dry out with northwest flow on the front side of the upper ridge. There should still be adequate humidity around for scattered afternoon and early evening t-storms. Should see storms form over the higher terrain first and then move out over the plains by mid-afternoon where most will dissipate due to plenty of CIN around. Precip amounts will likely be cut in half with a reduction in PW. A continuation of the nely upslope flow for much of the day on plains should produce temperatures similar to those on Tuesday, i.e., slightly below average. By Thursday, storm chances drop off even more as the upper ridge moves back over the area and temperatures aloft warm. Friday through Sunday, the upper ridge slowly shifts east of the state placing the area under a very warm and dry swly flow aloft. This is expected to result in temperatures well above average and a near zero chance of t-storms. Highs Fri and Sat on the plains in the upper 80s and lower 90s, and by Sun mainly in the 80s. Sunday night and Monday, models show a weak cold front dropping south through the area as a weak mid-level shortwave passes overhead. This would lead to slightly cooler temperatures and an increased chance of t-storms, mainly over northern sections of the CWA. && .AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon) Issued at 947 AM MDT Mon Jun 5 2017 Scattered thunderstorms will move across the Denver area this afternoon and early evening. Moved up the best chance for storms an hour or two...now perhaps as early as 19Z toward KBJC and then 20Z-23Z through KDEN. The storms will be capable of producing heavy rain, small hail, wind gusts to 40 knots, and brief MVFR ceilings and visibility. For tonight, once the storms move east of the Denver area, light winds will prevail through much of the night. A cold front will push through the Denver area 09Z to 12Z and bring northerly winds and lower clouds. Low clouds are expect for most of Tuesday with ceilings of 2500 to 5000 feet. && .BOU WATCHES/WARNINGS/ADVISORIES... None. && UPDATE...Barjenbruch SHORT TERM...Meier LONG TERM...Baker AVIATION...Barjenbruch
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1033 AM MDT Mon Jun 5 2017 COZ030>051-061645- Jackson County Below 9000 Feet- West Jackson and West Grand Counties Above 9000 Feet- Grand and Summit Counties Below 9000 Feet- South and East Jackson/Larimer/North and Northeast Grand/ Northwest Boulder Counties Above 9000 Feet- South and Southeast Grand/West Central and Southwest Boulder/ Gilpin/Clear Creek/Summit/North and West Park Counties Above 9000 Feet-Larimer and Boulder Counties Between 6000 and 9000 Feet- Jefferson and West Douglas Counties Above 6000 Feet/Gilpin/Clear Creek/Northeast Park Counties Below 9000 Feet- Central and Southeast Park County- Larimer County Below 6000 Feet/Northwest Weld County- Boulder And Jefferson Counties Below 6000 Feet/West Broomfield County- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County- Elbert/Central and East Douglas Counties Above 6000 Feet- Northeast Weld County-Central and South Weld County-Morgan County- Central and East Adams and Arapahoe Counties- North and Northeast Elbert County Below 6000 Feet/North Lincoln County- Southeast Elbert County Below 6000 Feet/South Lincoln County- Logan County-Washington County-Sedgwick County-Phillips County- 1033 AM MDT Mon Jun 5 2017 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight Scattered thunderstorms will continue to develop and become more numerous through the afternoon. The storms will transition from the mountains to the plains through the afternoon and early evening hours. Storms over the higher terrain and I-25 Urban Corridor will produce brief heavy rain, mainly small hail, and wind gusts up to 45 mph. A stronger storm could produce minor flooding in a burn scar, and minor street flooding in urban areas. Storms may become stronger on the plains, roughly along and east of a line from Greeley to Denver International airport to Castle Rock. Isolated brief severe storms will be capable of producing hail up to one inch in diameter and wind gusts to 60 mph. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Thunderstorm chances will increase Tuesday with a very moist post-frontal airmass covering the plains of northeast Colorado. Some storms over the Palmer Divide late on Tuesday could produce locally heavy rainfall. Thunderstorm coverage will become more scattered on Wednesday and Thursday. Drier and warmer weather will return for the weekend. .SPOTTER INFORMATION STATEMENT... Spotter activation is not anticipated today or tonight, but any reports of heavy rainfall or hail would be appreciated.
Special Weather Statement National Weather Service Denver CO 230 PM MDT MON JUN 5 2017 COZ040-041-045-046-052115- Elbert/Central and East Douglas Counties Above 6000 Feet CO- North and Northeast Elbert County Below 6000 Feet/North Lincoln County CO-Central and East Adams and Arapahoe Counties CO- North Douglas County Below 6000 Feet/Denver/West Adams and Arapahoe Counties/East Broomfield County CO- 230 PM MDT MON JUN 5 2017 ...SIGNIFICANT WEATHER ADVISORY FOR NORTHWESTERN ELBERT...CENTRAL ARAPAHOE AND SOUTH CENTRAL ADAMS COUNTIES UNTIL 315 PM MDT... At 229 PM MDT, Doppler radar was tracking a strong thunderstorm 6 miles east of Arapahoe Park, or 22 miles east of Denver, moving southeast at 15 mph. Nickel size hail and wind gusts up to 50 mph will be possible with this storm. Locations impacted include... Eastern Aurora, Bennett, Watkins and Manila Village. LAT...LON 3942 10449 3966 10469 3984 10452 3953 10417 TIME...MOT...LOC 2029Z 322DEG 12KT 3963 10456 BOWEN
The Denver radar (KFTG), 12 km away, was scanning. The volume nearest the first event began at 20:33 UTC.
2 thunderstorm wind, 1 tornado. Local standard time, as filed.
A weak landspout touched down briefly and tossed around some lawn furniture.
Intense downburst winds snapped a power pole near the interchange of Interstate 70 and US 36.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2017Every state in 2017This day in weather historyThe tornado archive for Colorado, 2017Warnings in Colorado, June 2017
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: 691891, 691895, 691894.