An isolated thunderstorm produced a brief non-supercell tornado in rural northeastern Washington county.
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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.
An isolated thunderstorm produced a brief non-supercell tornado in rural northeastern Washington county.
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 Jul 12, 1:11 PM MST, 1 hour 51 minutes earlier. Its key messages:
Area Forecast Discussion National Weather Service Denver/Boulder CO 211 PM MDT Fri Jul 12 2024 .KEY MESSAGES... - Heat wave through Sunday with temperatures reaching 100 to 105 degrees across the urban corridor and plains. Important to take steps to limit outdoor activity, find ways to cool off, and stay hydrated as much as possible. - A Heat Advisory is in effect today through 8 pm for the I-25 corridor, expanding across all the plains for Saturday and Sunday. - Slight heat relief possible by Monday, but more so by Tuesday and Wednesday. Increasing chance of showers and thunderstorms for that period. && .SHORT TERM /Through Saturday/... Issued at 205 PM MDT Fri Jul 12 2024 Limited cumulus development on satellite this aftn. There is still some potential for isold high based activity mainly along and south of I-70 over the higher terrain and across srn portions of Lincoln county. Radar also show a weak convergence boundary extending from Lincoln county into ern Washington county and Logan county. No cumulus along this boundary but not impossible an isold storm or two could develop along it, late this aftn or early this evening, where sfc based cape is maximized over Logan, Phillips and Sedgwick counties. Overnight through Sat, the center of a large upper level high will remain near the Four Corners area. Little change in 850-700 mb temps expected on Sat with highs staying in the 100-105 range across the plains. Record high at Denver is 100 on Sat, which should be broken. Meanwhile, there will be some increase in mid level moisture on Sat as water vapor imagery does show moisture over Utah rotating around the upper level high this aftn. As a result, will see at least widely sct high based shower/storms over the higher terrain Sat aftn. At lower elevations, with high T-TD spreads, could see isold high based showers, with mainly virga, producing gusty outflow winds across the I-25 Corridor as DCAPE values are decent. Over the far nern plains, sfc based CAPE is fcst to be from 500-1000 j/kg. Thus could see an isold strong storm or two if the cap can be broken by late aftn. && .LONG TERM /Saturday night through Friday/... Issued at 205 PM MDT Fri Jul 12 2024 Record to near record heat is expected to continue on Sunday as upper level high pressure dominates the Southern and Central Rockies. Max temperatures across the plains are expected to range between 100 and 105 degrees with 103 forecasted at DIA which would set a new record for the date. The high county will be quite warm as well with temperatures climbing above 80 in places such as Breckenridge, Dillon and Grand Lake. There should be enough mid level moisture around to produce isolated to scattered late afternoon and evening showers and storms, mainly over the higher terrain. Due to the lack of low level moisture, any showers and storms that form will most likely produce sprinkles and gusty winds. With the potential for dry lighting there may be some fire weather concerns across portions of the CWA. On Monday, the upper high is expected to weaken and flatten which will allow an upper level disturbance and associated cool front to move across Northeastern Colorado. Increased moisture behind the front should allow for a better chance of showers and storms which should result in somewhat cooler temperatures. Nevertheless, temperatures should still be hot across the plains with high ranging between 95 to 100 degrees. On Tuesday, the models are showing the upper ridge retrograding southwestward into Arizona in response to a potent shortwave moving across the Northern Great Lakes. Consequently, the upper flow aloft over Colorado should turn more northwesterly opening the door for occasional upper level disturbances and cold fronts. This should result in some relief in the heat along with higher precipitation chances, especially along and east of the Continental Divide. By Friday, temperatures may warm back up above 90 degrees on the plains with decreased precipitation chances. && .AVIATION /18Z TAFS through 00Z Sunday/... Issued at 205 PM MDT Fri Jul 12 2024 VFR conditions thru the period. Gusty north winds this aftn should become more northeast by 00Z and then decrease. Winds by mid evening will transition to a southerly direction. By 10z they may become light westerly. On Sat, winds will become north by late morning and then northeast by early aftn. There could be some virga late in the aftn with gusty microburst winds possible after 21z. && .FIRE WEATHER... Issued at 205 PM MDT Fri Jul 12 2024 Elevated fire danger will be in place across the plains foothills and higher valleys on Saturday due to hot and dry conditions along with low humidity levels. However, winds will be relatively light in most areas. && .BOU WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM MDT this evening for COZ038>040-043. Heat Advisory from 10 AM to 8 PM MDT Saturday for COZ038>040- 042>051. Heat Advisory from 10 AM to 8 PM MDT Sunday for COZ038>040- 042>051. && SHORT TERM...RPK LONG TERM...JK AVIATION...RPK FIRE WEATHER...RPK
Hazardous Weather Outlook National Weather Service Denver/Boulder CO 1002 AM MDT Fri Jul 12 2024 COZ030>051-131615- 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- 1002 AM MDT Fri Jul 12 2024 This hazardous weather outlook is for northeast and north central Colorado. .DAY ONE...Today and Tonight A Heat Advisory will be in place through 8 PM this evening for the urban corridor. Temperatures are expected to reach and surpass the 100 degree mark across the plains. Weak isolated thunderstorms and showers are possible across portions of the high country and eastern plains this afternoon that could produce gusty winds, light rainfall, and isolated dry lightning. .DAYS TWO THROUGH SEVEN...Saturday through Thursday Record or near record breaking heat will remain across the area through this weekend. High temperatures will reach the 100 to 105 degree range across the I-25 Urban Corridor and northeast plains both Saturday and Sunday. 90 plus degree heat can even be expected up to elevations near 8000 feet. Avoid outdoor activities during the heat of day, seek shade and air conditioning, and stay hydrated. Seek medical aid immediately if suffering signs of heat stroke. Isolated thunderstorms and showers are possible across the high country each day this weekend, with little rain but lightning and gusty winds possible. Slight relief in the heat is expected toward Monday although temperatures will still be well above normal. Further cooling is expected Tuesday into Wednesday with a higher chance of showers and storms at that time. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed today or tonight.
Special Weather Statement
National Weather Service Denver CO
331 PM MDT Fri Jul 12 2024
COZ049-122200-
Washington County CO-
331 PM MDT Fri Jul 12 2024
...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN WASHINGTON COUNTY
THROUGH 400 PM MDT...
At 330 PM MDT, Doppler radar was tracking a strong thunderstorm
capable of producing a landspout tornado near Burdett, or 18 miles
northeast of Akron, moving southeast at 20 mph.
HAZARD...Landspouts, wind gusts up to 50 mph, and half inch hail.
SOURCE...Radar indicated.
IMPACT...Landspout tornadoes can damage mobile homes, roofs,
vehicles, and trees. Outdoor objects may be tossed about.
Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Lone Star and Burdett.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare for sudden gusty winds. Secure loose objects and move to a
safe shelter inside a building or vehicle.
If outdoors, consider seeking shelter inside a building.
If a tornado is spotted seek shelter inside a sturdy building.
&&
LAT...LON 4035 10280 4020 10280 4020 10303 4043 10307
4043 10278 4035 10278
TIME...MOT...LOC 2130Z 317DEG 18KT 4033 10295
LANDSPOUT...POSSIBLE
MAX HAIL SIZE...0.50 IN
MAX WIND GUST...50 MPH
RPKSpecial Weather Statement
National Weather Service Denver CO
359 PM MDT Fri Jul 12 2024
COZ049-122230-
Washington County CO-
359 PM MDT Fri Jul 12 2024
...A STRONG THUNDERSTORM WILL IMPACT NORTHEASTERN WASHINGTON COUNTY
THROUGH 430 PM MDT...
At 358 PM MDT, Doppler radar was tracking a strong thunderstorm
capable of producing a landspout tornado 5 miles southwest of Lone
Star, or 14 miles northwest of Yuma, moving south at 15 mph.
HAZARD...Landspouts, wind gusts up to 50 mph, and nickel size hail.
SOURCE...Radar indicated.
IMPACT...Landspout tornadoes can damage mobile homes, roofs,
vehicles, and trees. Outdoor objects may be tossed about.
Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Otis, Lone Star, and Burdett.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Prepare for sudden gusty winds. Secure loose objects and move to a
safe shelter inside a building or vehicle.
If outdoors, consider seeking shelter inside a building.
If a tornado is spotted seek shelter inside a sturdy building.
&&
LAT...LON 4035 10280 4016 10279 4013 10297 4041 10302
4044 10282 4044 10278 4035 10278
TIME...MOT...LOC 2158Z 348DEG 12KT 4028 10289
LANDSPOUT...POSSIBLE
MAX HAIL SIZE...0.88 IN
MAX WIND GUST...50 MPH
RPKThe Denver radar (KFTG), 147 km away, was scanning. The volume nearest the first event began at 22:03 UTC.
1 tornado. Local standard time, as filed.
Path is estimated. The landspout tornado only lasted a few minutes.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2024Every state in 2024This day in weather historyThe tornado archive for Colorado, 2024Warnings in Colorado, July 2024
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: 1197647.