Tornadoes and Hail in Colorado, May 12, 2004

Name: Tornadoes and Hail in Colorado, May 12, 2004
Start: 2004-05-12T16:45
End: 2004-05-12T19:20
Location: Colorado

May 12, 2004 · NWS GLD · 12 events in 1 county or zone

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: 0
Injuries: 0
Property damage: None recorded
Crop damage: None recorded
Events: 12

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 GLD wrote it up.

Thunderstorms developed over several hours across southern Cheyenne County Colorado along a surface boundary and moved into portions of west-central Kansas during the evening. Several reports of tornadoes were received from storm spotters and law enforcement, including one tornado which toppled a windmill and pushed over numerous large trees. Strong thunderstorm winds also accompanied some of the thunderstorms with one downburst, associated with a strong rear-flank downdraft, removing a barn roof. Hail reports between 1 and 3 inches in diameter were common with the storms during the late afternoon and early evening hours.

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 Goodland, KS wrote its last area forecast discussion before the first event at May 12, 1:15 PM MST, 3 hours 30 minutes earlier.

Area forecast discussion, May 12, 1:15 PM MST, 3 hours 30 minutes before

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GOODLAND KS
215 PM MDT WED MAY 12 2004

.DISCUSSION...THE MAIN FORECASTING CHALLENGES IS THE POSITION AND
ENDING TIME OF PRECIPITATION TONIGHT AND TOMORROW. ANOTHER CONCERN
IS THE WIND TOMORROW MORNING...WITH THE HIGH PRESSURE MOVING INTO
THE AREA.

TONIGHT...THE MAIN FOCUS IS ON THE RAIN SHIELD THAT WILL DEVELOP
WITH THE SURFACE LOW MOVING ACROSS THE PAN HANDLE OF TEXAS AND OKLAHOMA.
THE BEST LOCATION TO RECEIVE RAIN APPEARS TO BE IN SOUTHWEST
NEBRASKA. ETA...GFS AND UKMET HAVE PRECIPITATION MOVING ACROSS THE
REGION WITH THE HEAVIEST AMOUNTS BEING LONG THE KANSAS AND NEBRASKA
BORDER. ETA 310K ISOTROPIC HAS GREAT UPGLIDE...WITH RELATIVE
HUMIDITIES REACHING 97%-99% ACROSS THE NORTHERN PART OF THE CWA.
ISOTROPIC LIFT DROPS OFF QUICKLY AROUND 12Z. WINDS WILL CONTINUE TO
BE BREEZY...WITH THE PRESSURE GRADIENT DEVELOPING BETWEEN THE HIGH
PRESSURE MOVING OUT OF MONTANA AND THE LOW PRESSURE SYSTEM.

THURSDAY/THURSDAY NIGHT...THE WIND IS THE MAIN CONCERN DURING THE
EARLY MORNING HOURS FOR THE EASTERN PART OF THE CWA. COLD AIR WILL
SLIDE IN WITH THE HIGH PRESSURE CAUSING A NICE PRESSURE GRADIENT
AGAINST THE LOW IN SOUTHEAST KANSAS. THE COLD AIR MOVING IN FROM
CANADA WILL CAUSE OUR TEMPERATURE TO BE MUCH COOLER...LOOKING AT
HIGHS IN THE MID TO UPPER 40S. PRECIPITATION WILL END AS THE LOW
MOVES OFF TO THE EAST NORTHEAST DURING THE DAY. THERE IS A SLIGHT
CHANCE OF PRECIPITATION FORMING ALONG THE FRONT RANGE MOVING INTO MY
EASTERN COLORADO COUNTIES.  HIGH PRESSURE WILL CONTINUE TO BUILD
OVER THE AREA...WHICH WILL BRING CLEARING SKIES AND ANOTHER COOL
NIGHT.

FRIDAY/FRIDAY NIGHT...THE UPPER LEVELS WILL BECOME ZONAL...WITH HIGH
PRESSURE DOMINATING THE REGION AT THE SURFACE. ALL OF THE MODELS ARE
SHOWING A NICE WARMING TREND ON FRIDAY...AS TEMPERATURES CLIMB BACK
TO THE MID 60S. THE HIGH PRESSURE WILL KEEP THE WINDS OUT OF THE
SOUTHWEST. LOW TEMPERATURES ON FRIDAY NIGHT WILL BE MILD...BEING
AROUND 10 TO 15 DEGREES WARMER THAN THURSDAY NIGHT.

IN THE EXTENDED PERIOD DAYS 4 THROUGH 7 (SATURDAY THROUGH
WEDNESDAY)...UPPER FLOW BECOMES MORE ZONAL LATE WEEKEND INTO THE
MIDDLE OF NEXT WEEK WITH MEAGER DYNAMICS AND MOISTURE AVAILABLE.
WILL KEEP THE EXTENDED FORECAST PERIOD DRY WITH PARTLY CLOUDY SKIES.
LATEST GFS AND ECMWF MODEL RUNS SHOW A TROUGH PASSING TO OUR NORTH
ON TUESDAY BUT WITH NO GULF OF MEXICO MOISTURE RETURN. WILL KEEP
HIGH TEMPERATURES MONDAY THROUGH WEDNESDAY IN THE MIDDLE 70S TO
AROUND 80 WHILE OVERNIGHT LOW TEMPERATURES WILL BE IN THE 40S.

&&

.GLD WATCHES/WARNINGS/ADVISORIES...
KS...NONE.
NE...NONE.
CO...NONE.

&&

SMITH/LAMMERS

Hazardous weather outlook, May 12, 9:55 AM MST, 6 hours 50 minutes before

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE GOODLAND KS
1055 AM MDT WED MAY 12 2004

COZ090>092-KSZ001>004-013>016-027>029-041-042-NEZ079>081-131200-
CHEYENNE KS-CHEYENNE COUNTY CO-DECATUR KS-DUNDY NE-GOVE KS-GRAHAM KS-
GREELEY KS-HITCHCOCK NE-KIT CARSON COUNTY CO-LOGAN KS-NORTON KS-
RAWLINS KS-RED WILLOW NE-SHERIDAN KS-SHERMAN KS-THOMAS KS-WALLACE KS-
WICHITA KS-YUMA COUNTY CO-

THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHWEST KANSAS...EXTREME
SOUTHWEST NEBRASKA...AND EAST CENTRAL COLORADO.

.DAY ONE...THIS AFTERNOON AND TONIGHT

SCATTERED THUNDERSTORMS WILL DEVELOP LATE THIS AFTERNOON ACROSS
EASTERN COLORADO AND NORTHWEST KANSAS. SOME OF THESE STORMS MAY
BECOME SEVERE DURING THE EARLY EVENING. THE MAIN THREAT WILL BE NEAR
AND SOUTH OF HIGHWAY 40 FROM CHEYENNE WELLS TO RUSSELL SPRINGS TO
GOVE. WIND PROFILES WILL BE VERY FAVORABLE FOR SUPERCELL
THUNDERSTORMS WITH LARGE HAIL AND DAMAGING WINDS. THERE WILL ALSO
BE SOME RISK OF TORNADOES FOR A BREIF TIME THIS EVENING. THE LIMITING
FACTORS ARE MARGINAL INSTABILITY AND RELATIVELY HIGH CLOUD BASES. IF
STORMS CAN SURVIVE THROUGH LATE EVENING...THEY WILL ENCOUNTER
CONDITIONS SLIGHTLY MORE FAVORABLE FOR TORNADOES...ESPECIALLY FROM
GREELEY COUNTY TO GOVE COUNTY IN
KANSAS. THE SEVERE THREAT WILL DIMINISH AFTER 10 PM MDT (11 PM CDT).
ELSEWHERE...STORMS MAY PRODUCE CLOUD TO GROUND LIGHTNING AND SMALL
HAIL NEAR AND NORTH OF INTERSTATE 70 OVERNIGHT.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THURSDAY AFTERNOON...BUT NO
SEVERE WEATHER IS EXPECTED. DANGEROUS CLOUD TO GROUND LIGHTNING WILL
BE THE PRIMARY THREAT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION MAY BE REQUIRED THIS AFTERNOON AND EVENING AFTER 2
PM MDT (3 PM CDT).

BURKE

In the hours before

Special weather statement, May 12, 4:35 PM MST, 10 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE GOODLAND KS
535 PM MDT WED MAY 12 2004

COZ091-092-KSZ013-014-027-028-041-042-130500-
CHEYENNE CO-GREELEY-KIT CARSON-LOGAN-SHERMAN-THOMAS-WALLACE-WICHITA-
535 PM MDT (635 PM CDT) WED MAY 12 2004

...A SEVERE THUNDERSTORM WATCH IS IN EFFECT FOR PORTIONS OF THE
TRISTATE AREA THROUGH 11 PM MDT (MIDNIGHT CDT)...

THE STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH
EFFECTIVE THIS EVENING FROM 535 PM MDT (635 PM CDT) UNTIL 11 PM MDT
(MIDNIGHT CDT).

THE SEVERE THUNDERSTORM WATCH INCLUDES KIT CARSON AND CHEYENNE
COUNTIES IN COLORADO. IN KANSAS THE COUNTIES INCLUDE SHERMAN...
THOMAS...WALLACE...LOGAN...GREELEY AND WICHITA.

HAIL UP TO ONE AND A HALF INCHES IN DIAMETER...WIND GUSTS TO 65
MPH ...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE
FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA.
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY DO PRODUCE
TORNADOES.

RJC

The radar

The national radar mosaic for the moment the first event began.

Open the radar archive at this moment

Event by event

8 hail, 3 tornado, 1 thunderstorm wind. Local standard time, as filed.

Hail, Cheyenne

When: May 12, 4:45 PM MST
Where: Cheyenne County, 9 mi SE of Kit Carson
Measured: 0.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.667, -102.667

Hail, Cheyenne

When: May 12, 4:54 PM MST
Where: Cheyenne County, 9 mi SE of Kit Carson
Measured: 0.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.667, -102.667

Hail covered the ground.

Tornado, Cheyenne

When: May 12, 5:13 PM MST to 5:15 PM MST
Where: Cheyenne County, 5 mi SW of Cheyenne Wells
Rating: F0
Path length: 0.5 mi
Path width: 50 yd
Reported by: STORM CHASER
Coordinates: 38.767, -102.417

Brief touchdown over open fields observed by storm chaser. No known damage.

Tornado, Cheyenne

When: May 12, 5:38 PM MST to 5:40 PM MST
Where: Cheyenne County, 3 mi SE of Cheyenne Wells
Rating: F0
Path length: 0.5 mi
Path width: 50 yd
Reported by: LAW ENFORCEMENT
Coordinates: 38.783, -102.317

Brief touchdown over open fields observed by law enforcement. No known damage.

Hail, Cheyenne

When: May 12, 5:50 PM MST
Where: Cheyenne County, 10 mi S of Arapahoe
Measured: 1 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.700, -102.167

Hail, Cheyenne

When: May 12, 6:09 PM MST
Where: Cheyenne County, 11 mi S of Arapahoe
Measured: 2.75 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.683, -102.167

Hail, Cheyenne

When: May 12, 6:09 PM MST
Where: Cheyenne County, 12 mi S of Arapahoe
Measured: 1 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.683, -102.167

Hail, Cheyenne

When: May 12, 6:28 PM MST to 6:29 PM MST
Where: Cheyenne County, Wild Horse
Measured: 0.75 in hail
Reported by: TRAINED SPOTTER
Coordinates: 38.817, -103.000

Hail covered the ground 1 inch deep.

Hail, Cheyenne

When: May 12, 6:37 PM MST
Where: Cheyenne County, 14 mi SW of Cheyenne Wells
Measured: 1 in hail
Reported by: GENERAL PUBLIC
Coordinates: 38.667, -102.533

Tornado, Cheyenne

When: May 12, 6:40 PM MST to 6:42 PM MST
Where: Cheyenne County, 10 mi SE of Kit Carson
Rating: F1
Path length: 0.5 mi
Path width: 100 yd
Reported by: GENERAL PUBLIC
Coordinates: 38.667, -102.650

Trees flattened and a windmill destroyed.

Thunderstorm Wind, Cheyenne

When: May 12, 6:50 PM MST
Where: Cheyenne County, 9 mi WSW of Cheyenne Wells
Measured: 69 kt (79 mph) estimated gust
Reported by: GENERAL PUBLIC
Coordinates: 38.767, -102.500

Barn roof blown off to east of structure. Not observed at time of incident. Damage likely caused by strong Rear Flank Downdraft based on radar signature. Time estimated at 750 pm MDT based on radar archive.

Hail, Cheyenne

When: May 12, 7:20 PM MST
Where: Cheyenne County, Arapahoe
Measured: 0.75 in hail
Reported by: NWS EMPLOYEE(OFF DUTY)
Coordinates: 38.850, -102.167

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 2004 Every state in 2004 This day in weather history The tornado archive for Colorado, 2004 Warnings in Colorado, May 2004

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: 5402494, 5402495, 5402502, 5402503, 5402496, 5402497, 5402498, 5402499, 5402500, 5402504, 5402579, 5402501.