Tornadoes and Hail in Colorado, May 22, 2008

Name: Tornadoes and Hail in Colorado, May 22, 2008
Start: 2008-05-22T10:15
End: 2008-05-22T16:47
Location: Colorado

May 22, 2008 · NWS BOU · 36 events in 6 counties and zones

Where it happened

Every event with a place to put it. Tap one for its entry below.

Tornadoes
Tropical storms and surge
Floods
Wind
Hail
Winter weather
Heat and drought
Cold
Fire, smoke and dust
Marine and coastal
Other

Open the live radar over this ground

The toll

Deaths: 1
Injuries: 79
Property damage: $147 million
Crop damage: None recorded
Events: 36

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.

What happened

The episode as NWS BOU wrote it up.

A powerful tornado swept north-northwestward across Weld County, carving a path of destruction, nearly 39 miles in length. The tornado, up to one-mile wide at times, initially touched down northeast of Platteville and finally lifted 6 miles west-northwest of Wellington. A tornado assessment in the aftermath of the tornado revealed extensive areas of damage. On the enhanced Fujita Scale there were pockets of EF3 damage, mainly near the Missile Silo Park Campground, and to businesses and home in eastern Windsor. Farmers also reported extensive damage to crops and irrigation equipment.

There was one fatality, and 78 injuries ranging from broken bones to minor cuts and lacerations. One man was killed when he tried to escape a trailer park in his motor home. Tractor trailers were flipped along U.S. Highway 85, and over 200 power poles were snapped or blown down. Approximately 60,000 people were left without electricity. The tornado overturned 15 railroad cars and destroyed a lumber car on the Great Western Railway of Colorado. The tornado also flattened Windsor's main feedlot and destroyed a dairy barn. Most of the four-hundred cows were killed in the tornado or destroyed later. In addition to the damaging winds, the thunderstorm also produced hail up to the size of baseballs.

Another tornado rated an EF1, from a separate severe thunderstorm, briefly touched down near Dacono and destroyed 5 buildings. The tornado overturned a five-wheel trailer and injured the man who was sitting inside.

Preliminary estimates from FEMA indicated 850 homes were damaged, and nearly 300 homes were significantly damaged or destroyed. The Poudre Valley Rural Electric Association reported $1 million of damage to electric transmission lines. Privately insured damages totaled $147 million, making it the state's 4th costliest disaster.

What forecasters said that day

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 May 22, 2:06 AM MST, 8 hours 9 minutes earlier.

Area forecast discussion, May 22, 2:06 AM MST, 8 hours 9 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER CO
306 AM MDT THU MAY 22 2008

.SHORT TERM...COMPLICATED FCST TODAY THRU THE EARLY EVENING HOURS AS
STG LATE SPRING STORM SYSTEM REMAINS OVER UTAH.  THE BIGGEST
QUESTION FOR TODAY IS EXACTLY WHERE A SFC LOW WILL DEVELOP AND WHERE
FNTL BNDRY ENDS UP BY AFTN.  BOTH NAM AND GFS SHOWED THIS LOW
DEVELOPING EAST OF DENVER TODAY HOWEVER BOTH RUC13 AND RUC20 HAS
THIS LOW FURTHER WEST OVER THE HIGHER TERRAIN.  IF THE RUCS ARE
RIGHT THEN LOW LEVEL FLOW ACROSS MOST OF NERN CO WILL BE MORE ELY
THRU THE AFTN HOURS WITH FNTL BNDRY POSSIBLY STALLING OUT OVER THE
PALMER DIVIDE.  THUS WOULD LEAD TO A COOL AND MOIST AIRMASS ACROSS
THE PLAINS WITH A LOW CLOUDY DECK MUCH OF THE DAY WITH THE MOST
UNTABLE AIRMASS OCCURRING FROM SOUHT OF A DENVER TO AKRON LINE.
MEANWHILE BOTH NAM AND GFS SHOW DECENT QG ASCENT OVER THE AREA THRU
THIS AFTN WITH FAVORABLE QG VERTICAL VELOCITIES LATER THIS MORNING
INTO THE AFTN HOURS.  AS A RESULT COULD SEE INCREASE IN
SHOWERS/TSTMS BY LATE MORNING INTO THE EARLY AFTN HOURS.  IF PCPN
OCCURS THIS EARLY IN THE DAY THE THREAT FOR SEVERE WX WOULD PROBABLY
BE REDUCED EXCEPT FOR POSSIBLY ALONG THE PALMER DIVIDE INTO LINCOLN
COUNTY.  TEMPS TODAY OVER NERN CO MAY STRUGGLE TO REACH 60 DEGREES
IN SOME AREAS IF RUC MODEL IS CORRECT WHICH IS SUPPORTED BY NAM
BUFFER DATA AS WELL.  THUS MY HIGHS MAY STILL END UP BEING TO WARM
AFTER ADJUSTING VALUES DOWNWARD.

IN THE MTNS THE MID LEVEL FLOW WILL BE SELY WHICH IS NOT A FAVORED
DIRECTION FOR PCPN EXCEPT OVER PARTS OF ZONE 34.  HOWEVER WITH
ADUNDANT MOISTURE...DECENT LAPSE RATES AND ABUNDANT MOISTURE SHOULD
STILL SEE SCT SHOWERS AND A FEW TSTMS.  WET BULB ZERO LEVEL ARE
AROUND 10000 FEET SO EXPECT SOME SNOW OVER THE HIGHER PASSES.

BY TONIGHT QG DESCENT ALONG WITH A SUBSTANTIAL DECREASE IN QG
VERTICAL VELOCITIES ARE SHOWN OVER NERN CO AFT 03Z SO IT APPEARS
BEST CHC FOR PCPN WILL BE IN THE EARLY EVENING HOURS.  IN THE MTNS
ONCE AGAIN MAY CONTINUE TO SEE SOME SCT PCPN OVERNIGHT WITH THE SNOW
LEVELS LOWERING POSSIBLY TO AROUND 9000 FEET.

ON THURSDAY...A STG SLY FLOW WL CONTINUE OVER NERN CO AS THE UPPER
LOW SPINS OVER UTAH.  A DRIER AMS IS PROGGED TO DVLP OVER THE SRN
HALF OF THE CWFA BY THURSDAY AFTN WITH DRY LINE PUSHING THE THETA-E
MSTR FURTHER N.  GRIDS ALREADY FAVOR HIGHER POPS ALONG THE NRN
BORDER SO ONLY MINOR ADJUSTMENTS EXPECTED.  AMS WL BE COOLER WITH
SOME LINGERING SHOWERS IN THE MRNG.  BEST POTENTIAL FOR SVR
THUNDERSTORMS WL BE OVER THE NERN CORNER OF THE STATE THU AFTN.  STG
SE WINDS OVER THE PLAINS THROUGH MUCH OF THE DAY. WL MENTION GUSTS
TO 50 MPH BUT HOLD OFF ON ANY HIGHLIGHTS AT THIS TIME.

.LONG TERM...NOT MUCH TO CHANGE IN THE FORECAST PACKAGE THIS TIME
AROUND.  THE UPPER AIR PATTERN OVER THE WESTERN U.S. IS GOING TO
GRADUALLY CHANGE OVER THE WEEKEND AFTER THE LARGE UPPER LOW MEANDERS
OVER THE SOUTHWEST U.S. THE REST OF THIS WEEK.  BY EARLY NEXT WEEK
THE MODELS INDICATE THAT THE UPPER LOW WILL HAVE WEAKENED/OPENED UP
AND BEGUN SHEARING OUT WITH COLORADO COMING UNDER INCREASING
SOUTHWESTERLY FLOW ALOFT.  IN THE MEANTIME...IT APPEARS THAT FRIDAY
COULD POSSIBLY BE A THIRD ROUND OF WHAT WE SAW LAST EVENING.  WITH
THE STATE UNDER SLIGHTLY DIFFLUENT MERIDIONAL FLOW ALOFT AND A
SURFACE LOW LINGERING SOMEWHERE OVER EASTERN COLORADO OR EASTERN
WYOMING...IT IS POSSIBLE THAT WE MAY STILL BE ADVECTING GULF
MOISTURE INTO THE REGION THROUGH FRIDAY AFTERNOON AND EVENING.  ALL
OF THE MODELS WANT TO MOVE THE SURFACE LOW NORTHWARD OVER TIME...BUT
WITH THE LARGE UPPER LOW BEING VERTICALLY STACKED AND NEARLY
BAROTROPIC...IT IS DIFFICULT TO SEE WHY THERE WOULD BE MUCH
NORTHWARD MOVEMENT OF THE LOW.  LEE TROFFING IN THE SOUTHEAST
QUADRANT OF THE SYSTEM COULD ACTUALLY BE ENOUGH TO KEEP THE LOW
CLOSER TO SOUTHEAST COLORADO OR NORTHEAST NEW MEXICO THROUGH THE END
OF THE WEEK.  THE POSITION OF THE SURFACE LOW IS GOING TO BE
CRITICAL IN DETERMINING WHERE THE HEAVIEST WEATHER IS GOING TO BE.
FOR NOW WILL GO ALONG WITH PRIOR THINKING THAT THE SURFACE LOW WILL
MIGRATE FAR ENOUGH NORTH THAT LOWER CHANCES OF PRECIPITATION ARE IN
ORDER FOR OUR FORECAST AREA.  THIS BLENDS WELL WITH WHAT THE OTHER
OFFICES ARE FORECASTING.

THE OTHER ITEM IN THE FORECAST PACKAGE IS THE APPEARANCE THAT THE
FIRST HALF OF NEXT WEEK COULD BE EVEN MORE ACTIVE THAN THE CURRENT
SITUATION.  AT THAT TIME...THE STATE WILL BE UNDER MODERATE TO
STRONG SOUTHWESTERLY FLOW ALOFT WHILE THE ECMWF SHOWS A CANADIAN
SURFACE HIGH DROPPING OVER THE NORTHERN PLAINS.  UPSLOPE EASTERLIES
BEHIND THE CANADIAN FRONT COULD CONTINUE ACROSS NORTHEAST COLORADO
FROM MONDAY THROUGH AT LEAST WEDNESDAY.  THE GRIDS PRESENTLY HAVE 20
PERCENT POPS IN FOR THOSE DAYS WHICH IS SUFFICIENT FOR NOW.

&&

.AVIATION...IFR CONDITIONS POSSIBLE EARLY THIS MORNING THEN BECOMING
BECOME MVFR BY 16Z OR 17Z.  SCATTERED SHOWERS AND TSTMS MAY DEVELOP
BY 18Z AND CONTINUE THRU 21Z OR SO WITH BRIEF HEAVY RAIN...GUSTY
WINDS AND SMALL HAIL POSSIBLE.  PCPN CHANCES MAY DIMINISH BY EARLY
EVENING.  WINDS TODAY MAY STAY ESE THIS MORNING AND THEN SHIFT MORE
NELY BY MIDDAY BEFORE BECOMING SWLY BY LATE AFTN AS CONVECTION MOVES
EAST OF THE AREA.

&&

.BOU WATCHES/WARNINGS/ADVISORIES...NONE.

&&

RPK/KDRBY

Hazardous weather outlook, May 22, 9:59 AM MST, 16 minutes before

HAZARDOUS WEATHER OUTLOOK...CORRECTED
NATIONAL WEATHER SERVICE DENVER CO
1059 AM MDT THU MAY 22 2008

COZ030>051-231200-
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-
1059 AM MDT THU MAY 22 2008

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST AND NORTH CENTRAL
COLORADO.

.DAY ONE...TODAY AND TONIGHT

SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED ACROSS THE FRONT
RANGE FOOTHILLS...URBAN CORRIDOR AND NORTHEAST PLAINS THIS
AFTERNOON.  A FEW OF THE STORMS MAY BECOME SEVERE ESPECIALLY EAST OF
A FORT MORGAN TO BYERS TO LIMON LINE AND MAY PRODUCE VERY LARGE
HAIL...DAMAGING WINDS AND A FEW TORNADOES.  ELSEWHERE ISOLATED
SEVERE STORMS ARE POSSIBLE OVER THE REST OF NORTHEAST COLORADO AND
MAY PRODUCE HAIL TO ONE INCH IN DIAMETER ALONG WITH DAMAGING WINDS.
ALSO SOME VERY HEAVY RAIN MAY OCCUR WITH THE STORMS.  IN ADDITION
SOUTHEAST WINDS OF 20 TO 35 MPH WITH SOME GUSTS TO 45 MPH WILL OCCUR
OVER THE NORTHEAST PLAINS THROUGH THE AFTERNOON.

IN THE MOUNTAINS EXPECT SCATTERED SHOWERS AND THUNDERSTORMS WITH
GUSTY WINDS AND SMALL HAIL.  THE SNOW LEVEL WILL BE AROUND 10000
FEET WITH A FEW INCHES OF SNOW POSSIBLE OVER THE HIGHER PASSES.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

THERE WILL BE A SLIGHT CHANCE OF LATE AFTERNOON AND EVENING
THUNDERSTORMS ACROSS THE ENTIRE AREA FRIDAY THROUGH SUNDAY. A FEW
THUNDERSTORMS ON THE NORTHEAST PLAINS MAY BECOME SEVERE. ALTHOUGH IT
IS DIFFICULT TO TELL HOW WIDESPREAD THUNDERSTORM ACTIVITY WILL BE ON
ANY PARTICULAR DAY...AREAS TO THE NORTH AND EAST OF A GREELEY TO
LIMON LINE WILL HAVE THE BETTER CHANCES OF SEEING THUNDERSTORM
ACTIVITY ON FRIDAY THROUGH SUNDAY. EARLY NEXT WEEK...THE SURFACE
PRESSURE PATTERNS WILL CHANGE AND THUNDERSTORM ACTIVITY MAY BECOME
MORE CONCENTRATED ALONG THE FRONT RANGE FOOTHILLS AND URBAN
CORRIDOR.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE NEEDED AFTER 1 PM OVER PORTIONS OF
NORTHEAST COLORADO.

COOPER/MEIER

In the hours before

Local storm report, May 22, 7:47 AM MST, 2 hours 28 minutes before

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE DENVER CO
847 AM MDT THU MAY 22 2008

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0940 PM     NON-TSTM WND DMG N BRUSH                 40.26N 103.63W
05/21/2008                   MORGAN             CO   TRAINED SPOTTER

            STREET LIGHTS AND POWER LINES BLOWN DOWN. WINDOW IN HOME
            DAMAGED

0855 PM     TSTM WND GST     STERLING                40.65N 103.21W
05/21/2008  M63.00 MPH       LOGAN              CO   TRAINED SPOTTER

0816 PM     TSTM WND GST     STERLING                40.65N 103.21W
05/21/2008  M66.00 MPH       LOGAN              CO   TRAINED SPOTTER

0735 PM     TSTM WND GST     AKRON                   40.16N 103.21W
05/21/2008  M64.00 MPH       WASHINGTON         CO   ASOS

0700 PM     TSTM WND GST     NNW CROOK               40.86N 102.80W
05/21/2008  M60.00 MPH       LOGAN              CO   TRAINED SPOTTER

0630 PM     TSTM WND DMG     W PLEASANT VALLEY       40.61N 102.12W
05/21/2008                   PHILLIPS           CO   TRAINED SPOTTER

            IRRIGATION SPRINKLER OVERTURNED. 3 TON GRAIN FEEDER MOVED
            FROM PASTURE TO BARN. 3/4 INCH RAINFALL. ESTIMATED WIND
            GUSTS TO 65 MPH FROM SURROUNDING OBSERVATIONS.

0630 PM     TSTM WND DMG     18 SSE BRUSH            40.02N 103.50W
05/21/2008                   MORGAN             CO   TRAINED SPOTTER

            THUNDERSTORM WINDS KNOCKED DOWN A CARPORT INJURING ONE
            PERSON

0630 PM     TSTM WND GST     CROOK                   40.86N 102.80W
05/21/2008  M60.00 MPH       LOGAN              CO   AMATEUR RADIO

0600 PM     TSTM WND DMG     STERLING                40.65N 103.21W
05/21/2008                   LOGAN              CO   COUNTY OFFICIAL

            OUTFLOW WINDS FROM THUNDERSTORMS KNOCKED DOWN POWER LINES
            AND A TREE

0540 PM     TSTM WND GST     1 N ST PETERSBURG       40.57N 102.82W
05/21/2008  M61.00 MPH       LOGAN              CO   TRAINED SPOTTER

0530 PM     TSTM WND GST     5 NNE HILLROSE          40.39N 103.47W
05/21/2008  M65.00 MPH       MORGAN             CO   TRAINED SPOTTER

0516 PM     HAIL             8 S LONE STAR           40.24N 102.85W
05/21/2008  M1.00 INCH       WASHINGTON         CO   TRAINED SPOTTER

0447 PM     TSTM WND GST     FLEMING                 40.68N 102.84W
05/21/2008  M66.00 MPH       LOGAN              CO   AMATEUR RADIO

0445 PM     TSTM WND GST     AKRON                   40.16N 103.21W
05/21/2008  M66.00 MPH       WASHINGTON         CO   TRAINED SPOTTER

&&

BENTON

The radar

The Denver radar (KFTG), 62 km away, was scanning. The volume nearest the first event began at 17:14 UTC.

Open the radar archive at this moment

Event by event

31 hail, 3 tornado, 2 thunderstorm wind. Local standard time, as filed.

Hail, Jefferson

When: May 22, 10:15 AM MST
Where: Jefferson County, 2.74 mi WNW of Golden
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 39.760, -105.270

Hail, Weld

When: May 22, 10:19 AM MST
Where: Weld County, 2.1 mi SW of Gilcrest
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.260, -104.800

Tornado, Weld

When: May 22, 10:26 AM MST to 11:08 AM MST
Where: Weld County, 0.87 mi NNW of Platteville Arpt to 5.65 mi WNW of Severance
Rating: EF3
Path length: 24.26 mi
Path width: 1,760 yd
Continued into: Larimer, Co (BOU)
Deaths: 1 direct, 0 indirect
Injuries: 78 direct, 0 indirect
Property damage: $147 million
Reported by: Trained Spotter
Coordinates: 40.232, -104.754

A powerful tornado swept north-northwestward across Weld County and into Larimer County, carving a path of destruction, nearly 39 miles in length. The tornado, up to one-mile wide at times, initially touched down northeast of Platteville and finally lifted 6 miles west-northwest of Wellington. A tornado assessment in the aftermath of the tornado revealed extensive areas of damage. On the enhanced Fujita Scale there were pockets of EF3 damage, mainly near the Missile Silo Park Campground, and to businesses and home in eastern Windsor.

There was one fatality, and 78 injuries. One man was killed when he tried to escape the trailer park in his motor home. Preliminary estimates from FEMA indicated 850 homes were damaged, and nearly 300 homes were significantly damaged or destroyed. Privately insured damages totaled $147 million, and the Poudre Valley Rural Electric Associated reported $1 million of damage to electric transmission lines.

Hail, Larimer

When: May 22, 10:30 AM MST
Where: Larimer County, 2.96 mi NNE of Drake
Measured: 1.75 in hail
Reported by: Trained Spotter
Coordinates: 40.470, -105.310

Hail, Larimer

When: May 22, 10:45 AM MST
Where: Larimer County, 2.6 mi NE of Timnath
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.560, -104.950

Hail, Larimer

When: May 22, 10:47 AM MST
Where: Larimer County, 0.69 mi S of Black Hollow Jct
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.570, -105.020

Hail, Weld

When: May 22, 10:48 AM MST
Where: Weld County, 2.1 mi NW of Windsor
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.490, -104.910

Hail, Weld

When: May 22, 10:54 AM MST
Where: Weld County, 2.1 mi NW of Windsor
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 40.490, -104.910

Hail, Weld

When: May 22, 10:56 AM MST
Where: Weld County, 2.1 mi NW of Windsor
Measured: 2.75 in hail
Reported by: Trained Spotter
Coordinates: 40.490, -104.910

Hail, Larimer

When: May 22, 11:03 AM MST
Where: Larimer County, 0.87 mi SW of Ft Collins Airpark
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.570, -105.040

Hail, Boulder

When: May 22, 11:05 AM MST
Where: Boulder County, 1.48 mi NNE of Longmont
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 40.190, -105.090

Tornado, Larimer

When: May 22, 11:08 AM MST to 11:16 AM MST
Where: Larimer County, 2.1 mi NE of Timnath to 1.05 mi E of Owl Canyon
Rating: EF1
Path length: 14.43 mi
Path width: 500 yd
Reported by: Trained Spotter
Coordinates: 40.550, -104.950

A powerful tornado continued into Larimer County. A barn and two out buildings were destroyed near Timnath. A center pivot was overturned and a parked car was swept around the corner of a house and rolled over. The tornado finally lifted 6 miles west-northwest of Wellington.

Hail, Boulder

When: May 22, 11:10 AM MST
Where: Boulder County, 1.06 mi E of Longmont Muni Arpt
Measured: 1 in hail
Reported by: Amateur Radio
Coordinates: 40.170, -105.150

Hail, Weld

When: May 22, 11:16 AM MST
Where: Weld County, 2.22 mi WSW of Liberty
Measured: 2 in hail
Reported by: Trained Spotter
Coordinates: 40.170, -105.060

Hail, Boulder

When: May 22, 11:20 AM MST
Where: Boulder County, 0.53 mi W of Longmont
Measured: 1 in hail
Reported by: NWS Employee
Coordinates: 40.170, -105.110

Hail, Boulder

When: May 22, 11:20 AM MST
Where: Boulder County, 1.38 mi N of Longmont
Measured: 1.5 in hail
Reported by: Trained Spotter
Coordinates: 40.190, -105.100

Hail, Weld

When: May 22, 11:20 AM MST
Where: Weld County, 0.87 mi SW of Idaho Creek
Measured: 1.25 in hail
Reported by: Trained Spotter
Coordinates: 40.110, -105.030

Hail, Boulder

When: May 22, 11:28 AM MST
Where: Boulder County, 0.53 mi W of Longmont
Measured: 1.25 in hail
Reported by: Trained Spotter
Coordinates: 40.170, -105.110

Hail, Boulder

When: May 22, 11:30 AM MST
Where: Boulder County, 0.53 mi W of Longmont
Measured: 1.5 in hail
Reported by: NWS Employee
Coordinates: 40.170, -105.110

Hail, Larimer

When: May 22, 11:30 AM MST
Where: Larimer County, 1.38 mi N of Loveland
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.420, -105.070

Hail, Larimer

When: May 22, 11:30 AM MST
Where: Larimer County, 1.74 mi NW of Loveland
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 40.420, -105.090

Thunderstorm Wind, Weld

When: May 22, 11:30 AM MST
Where: Weld County, 8.89 mi WSW of Nunn
Measured: 56 kt (64 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 40.640, -104.920

Tornado, Weld

When: May 22, 11:30 AM MST to 11:32 AM MST
Where: Weld County, 2.53 mi WSW of Dacono
Rating: EF1
Path length: 0.1 mi
Path width: 100 yd
Injuries: 1 direct, 0 indirect
Reported by: Law Enforcement
Coordinates: 40.060, -104.970

A tornado touched down and destroyed 5 buildings near Dacono. One person was injured. The tornado overturned a five-wheel trailer and injured the man who was sitting inside.

Hail, Larimer

When: May 22, 11:40 AM MST
Where: Larimer County, 1.73 mi WSW of Berthoud
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 40.290, -105.110

Hail, Larimer

When: May 22, 11:45 AM MST
Where: Larimer County, 1.38 mi N of Berthoud
Measured: 0.88 in hail
Reported by: Trained Spotter
Coordinates: 40.320, -105.080

Hail, Larimer

When: May 22, 11:45 AM MST
Where: Larimer County, 1.38 mi S of Loveland
Measured: 1.75 in hail
Reported by: Trained Spotter
Coordinates: 40.380, -105.070

Hail, Larimer

When: May 22, 11:51 AM MST
Where: Larimer County, 1.38 mi N of Loveland
Measured: 1 in hail
Reported by: NWS Employee
Coordinates: 40.420, -105.070

Hail, Larimer

When: May 22, 11:57 AM MST
Where: Larimer County, 0.87 mi NE of Drakes
Measured: 0.75 in hail
Reported by: Storm Chaser
Coordinates: 40.560, -105.070

Hail, Larimer

When: May 22, 12:04 PM MST
Where: Larimer County, Wellington
Measured: 1 in hail
Reported by: NWS Employee
Coordinates: 40.700, -105.000

Thunderstorm Wind, Larimer

When: May 22, 12:15 PM MST
Where: Larimer County, Wellington
Measured: 76 kt (87 mph) estimated gust
Reported by: Trained Spotter
Coordinates: 40.700, -105.000

Strong winds damaged a loafing shed.

Hail, Washington

When: May 22, 12:19 PM MST
Where: Washington County, 6.43 mi ENE of Pinneo
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 40.260, -103.310

Hail, Larimer

When: May 22, 12:30 PM MST
Where: Larimer County, 4.15 mi S of Poudre Park
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.620, -105.300

A tree fell on a house.

Hail, Weld

When: May 22, 12:47 PM MST
Where: Weld County, 2.95 mi NW of Windsor
Measured: 2 in hail
Reported by: Amateur Radio
Coordinates: 40.500, -104.920

Hail, Larimer

When: May 22, 12:54 PM MST
Where: Larimer County, 0.53 mi W of Berthoud
Measured: 1 in hail
Reported by: Amateur Radio
Coordinates: 40.300, -105.090

Hail, Weld

When: May 22, 2:55 PM MST
Where: Weld County, 11.04 mi ESE of Rockport
Measured: 0.75 in hail
Reported by: Trained Spotter
Coordinates: 40.830, -104.590

Hail, Phillips

When: May 22, 4:47 PM MST
Where: Phillips County, 2.96 mi ENE of Haxtun Muni Arpt
Measured: 1 in hail
Reported by: Trained Spotter
Coordinates: 40.640, -102.550

The people who died

As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.

Event	Date	Age	Sex	Where	Kind
Tornado, Weld	2008-05-22	52	Male	Vehicle/Towed Trailer	Direct

What these are

Hail: Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
Tornado: A violently rotating column of air in contact with the ground and extending from a thunderstorm, filed with its path, width and Fujita or Enhanced Fujita rating from the damage survey.
Thunderstorm Wind: Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Colorado in 2008 Every state in 2008 This day in weather history The tornado archive for Colorado, 2008 Warnings in Colorado, May 2008

Sources

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: 93577, 93578, 93763, 93579, 93580, 93581, 93582, 93583, 93584, 93585, 93586, 126020, 93587, 93588, 93589, 93590, 93591, 93592, 93593, 93594, 93595, 93611, 93764, 93596, 93597, 93598, 93599, 93600, 93601, 93610, 93602, 93603, 93604, 93605, 93606, 93607.