A Pacific storm system brought much needed snow to the mountains and foothills, with a mix of rain and snow in the plains. The most appreciable snowfall occurred from central Jefferson County north into Larimer 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.
A Pacific storm system brought much needed snow to the mountains and foothills, with a mix of rain and snow in the plains. The most appreciable snowfall occurred from central Jefferson County north into Larimer County. Storm totals included: 20 inches just east of Buckhorn Mountain, 13 inches at Coal Creek, 12 inches, 7 miles north of Glen Haven and Red Feather Lakes, 11 inches, 3 miles north of Allenspark, 8 miles northwest of Evergreen, Gold Hill and 3 miles west of Jamestown, 10 inches, 8 miles north of Blackhawk, 3 miles west of Conifer, Crow Hill and Estes Park, 9 inches, 4 miles south of Evergreen and 3 miles south of Rollinsville, 8 inches near Genesee and Golden. Lesser amounts ranging from 3 to 7 inches were reported elsewhere.
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 23, 1:40 PM MST, 8 hours 20 minutes earlier.
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
240 PM MDT THU MAY 23 2002
THE RIGHT THINGS ARE COMING TOGETHER THIS EVENING FOR A GOOD CHANCE
FOR PRECIP ACROSS CWA. CURRENT ZN FCST IS IN LINE AS PRECIP WILL BE
IN THE FORM OF SNOW IN THE HIGH COUNTRY...RAIN SNOW MIX IN THE URBAN
CORR AND RAIN OUT ON THE PLAINS. WILL UPGRADE TO A WINTER STORM
WARNING IN THE FOOTHILLS AND ALSO INCLUDE THE MTN ZNS AS SNOW AMT
CRIT LOOKS LIKE IT WILL BE MET. GETTING VARYING AMOUNTS OF ACCUM
FROM MESOSCALE SNOW MODELS BUT LOWER THRESHOLDS SHD BE ACHIEVED.
CANT RULE OUT CONVECTIVE PROCESSES THIS TIME OF YEAR AND GRIDS POINT
TO DECENT INSTABILITY FOCUSED IN THE 03Z-06Z TIME FRAME. UPSLOPE
ALREADY TAKING PLACE ACROSS THE NORTHEASTERN PLAINS AT MIDDAY LIKE
YESTERDAYS MESOETA IMPLIED. COLDER SFC AIR AND STRATUS KNOCKING AT
THE STATELINE AND WILL ARRIVE LATE AFTERNOOON EARLY EVE. IR SAT
SHOWING STRONG CONCENTRATED AREA OF LIFT JUST NORTH OF STRONGEST JET
WINDS WHICH ARE EXPECTED TO CLIP NORTHEAST NMEX AND SOUTHEAST CORNER
OF STATE OVERNIGHT. RIGHT NOW LOOKS LIKE THE PRECIP PRODUCTION OF
THE STORM SYSTEM WILL BE A QUICK OVERNIGHT SHOT AND THEN OUT OF AREA
BY LATE MORN/EARLY AFTN. BEST EASTERLIES UPTO 650MB COMMENCES NEAR
00Z FRI BUT SWINGS TO SOUTHWESTERLY JUST ABOVE THE SFC IN THE 12-15Z
TIMEFRAME. 700MB TEMPS WILL GO IN THE -2 TO -4 DEGC RANGE OVERNIGHT
SO WILL EXPECT TEMPS IN THE URBAN CORR AND PLAINS TO STAY ABOVE THE
FREEZING MARK IN A MOIST ENVIRON. SFC LAYER FOR FRI WILL REMAIN
LIGHT SOUTHEASTERLY IN THE DENSER AIR THROUGH THE EVE HRS WITH A
GRADUAL DECREASE IN PRECIP AND CLOUDS THROUGH THE DAY WITH A GOOD
WARMUP. MESO MDLS REFRAIN FROM STRONG DOWNSLOPE FRI AFTN BEHIND
TROUGH SO SFC MOISTURE MAY HANG AROUND FOR THE NIGHT. A CLEAR FRIDAY
NIGHT COULD SPELL ANOTHER CHILLY/FREEZING NIGHT CAUSING HARM TO
SMALL VEG IF DEWPTS DO COME DOWN SIG. LATER PDS CAN DETERMINE IF ADV
IS NEEDED FOR THIS BUT TEMP GUIDANCE STAYING AROUND THE 40 DEGF
MARK. SATURDAY STILL LOOKS LIKE A STABLE DAY AS A TREND TO WARMING
AND RIDGING ALOFT BEGINS AND THEN SFC SOUTHEASTERLIES RESUMING IN
THE AFTN/EVE. RIDGE BECOMES STRONGER FOR SUNDAY WITH A GOOD
POSSIBILITY OF SOME WEAK LEE TROUGHING EARLY IN THE DAY AHEAD OF A
WEAK DISTURBANCE PASSING OVER THE STATE IN THE AFTERNOON. WILL
REINTRODUCE SOME POPS FOR SUNDAY AFTN WITH SLIGHTLY DEEPER MOISTURE
ARRIVING FROM THE SOUTHEAST AND INCREASING INSTABILITY ALOFT.
LONG TERM DISCUSSION: MONDAY..TUESDAY AND WED CONTINUE TO LOOK
SOMEWHAT UNSETTLED AS FLOW ALOFT TRENDS TO GENERAL TROUGHINESS OVER
THE WESTERN USA...INCLUDING THE ROCKIES. MID AND UPPER LVL FLOW
BECOMES WEAK AND MOSTLY UNORGANIZED OVER THE AREA IN THE EXT BUT
OWING TO CLIMO...CANNOT RULE OUT THAT SUFFICIENT MOISTURE COULD BE
AROUND FOR POPS DESPITE WHAT LOOKS LIKE BENIGN FORCING WEAK
PROGRESSION AND NO JET. THIS WEAK FLOW BECOMES A RIDGE BY THURSDAY
ACCORDING TO MFR WITH LOW AND MID LVL WARM MOISTURE SLIDING UNDER
RIDGE. FREDIN
.DEN...WINTER STORM WARNING TONIGHT FOR THE NORTH CENTRAL MOUNTAINS
AND NORTHERN FRONT RANGE FOOTHILLS...ZNS 33>36.The national radar mosaic for the moment the first event began.
2 winter storm. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2002Every state in 2002This day in weather historyWarnings in Colorado, May 2002
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: 5297819, 5297820.