A very slow moving Pacific storm system parked near the Four Corners region allowed for heavy snow to develop above 6500 feet, with a mix of rain and snow across the lower elevations. South Park received the heaviest snowfall, with a total of 41 inches reported 15 miles northwest of Hartsel.
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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 very slow moving Pacific storm system parked near the Four Corners region allowed for heavy snow to develop above 6500 feet, with a mix of rain and snow across the lower elevations. South Park received the heaviest snowfall, with a total of 41 inches reported 15 miles northwest of Hartsel. Across the Urban Corridor, the mix of rain and snow totalled 2 to 3 inches of liquid precipitation. Other storm totals included: 40 inches, 5 miles south of Antero Reservoir, 39 inches, 2 miles north of Fairplay, 36 inches, 3 miles north of Alma, 32 inches in Fairplay, 24 inches at Elizabeth, 23 inches, 4 miles west of Jamestown, 21 inches at Crow Hill, 4 miles southwest of Estes Park and Idaho Springs, 19 inches, 8 miles north of Blackhawk, 18 inches at Coal Creek, Genesee and 11 miles southwest of Morrison and 16 inches at Estes Park. Elsewhere, snow amounts ranged from 6 to 12 inches.
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 2, 2:10 PM MST, 2 hours 50 minutes earlier.
NORTHEAST AND NORTH CENTRAL COLORADO AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE DENVER COLORADO
310 PM MDT WED MAY 2 2001
SHORT TERM DISCUSSION: LOTS OF QUESTIONS TO ANSWER TONIGHT.
BIGGEST ONE IS IF HEAVY BANDED PRECIPITATION WILL WORK SOUTHWARD
ACROSS THE CWA. THEN...IF THIS HAPPENS...HOW FAR AND WHEN?
SATELLITE LOOP IS SHOWING SOME ENHANCEMENT DEVELOPING OVER THE
CENTRAL AND PORTIONS OF THE SOUTHERN MOUNTAINS. WITH THIS
SAID...BELIEVE FINER RESOLUTION MODELS ARE OK WITH DEVELOPING/
SPREADING HEAVIER PRECIPITATION ALONG THE REST OF THE FRONT RANGE
AFT 03Z THIS EVENING. HOWEVER...THEY MAY BE A BIT TOO FAST AND
HEAVY IF THEIR UPPER AIR FEATURES ARE A TAD TOO FAR EAST AS WATER
VAPOR LOOP SUGGESTS. 18Z MM5 AND ETA INDICATE 1.0 TO AS MUCH AS 2.0
INCHES OF WATER BY 18Z THURSDAY. BELIEVE MOST OF THIS SHOULD BE
SNOW ALONG THE FRONT RANGE WITH WET BULB ZERO LEVELS AROUND 6500
FEET AND CURRENT OBS SUGGESTING EVEN A LITTLE COLDER THAN THAT WITH
NORTHERLY SURFACE FLOW KEEPING WARMER AIR TO THE EAST. WILL STILL
HAVE SOME MIX ALONG THE I-25 CORRIDOR EARLY BASED ON CURRENT
OBS...BUT THEN ALL SNOW AS HEAVIER PRECIPITATION RATES KICK IN.
OVER THE NORTHEAST PLAINS...SHOULD SEE A GRADUAL CHANGE OVER AS WELL
IN MOST AREAS AS THE SOMEWHAT HEAVIER PRECIP MOVES IN. WILL UPGRADE
TO WARNING IN THE FORT COLLINS AREA...BUT KEEP WATCHES FROM BOULDER
SOUTHWARD IN CASE BANDS DO NOT SPREAD THIS WAY AS AVN MODEL
SUGGESTS. IF IT DOES FILL IN ACROSS DENVER...COULD EASILY BE
LOOKING AT 10 INCHES OF SNOWFALL WHICH WOULD WREAK HAVOC ON TREES
AND POWER LINES.
MOUNTAINS DOING GOOD WITH SNOW ALREADY AS MASSIVE FRONTOGENETICAL
BAND IS PRODUCING ENHANCED PRECIP RATES OVER JACKSON AND NORTHERN
LARIMER COUNTIES. WITH FRONTOGENETIC AREA REMAINING NEARLY
STATIONARY...WILL ISSUE WARNINGS FOR ALL MOUNTAINS AND HIGH VALLEYS
(3 INCHES IN WALDEN (VALLEY) EARLIER TODAY). NORTHERN FOOTHILLS
COULD SEE 3 FEET FROM THIS STORM WITH COMBINATION OF DYNAMICS AND
UPSLOPE.
BARJENBRUCH
LONG TERM DISCUSSION: MDS PRESENTING QUITE A MYRIAD OF SOLNS FOR
THE UPR LOW NOW DVLPG SOMEWHERE OVR SRN UT. ETA...AS HAS BEEN THE
CASE FOR THE PAST FEW RUNS...HAS BEEN THE MOST PROGRESSIVE WITH THE
LOW BY BRINGING IT EWD THRU SRN CO DURG THE DAY FRI. NGM SLOWER AND
FURTHER S...AND THE AVN THE SLOWEST. THE AVN HAS BEEN THE MOST
CONSISTANT WITH FEATURE AND SEEMS TO HAVE A SLGTLY BTR HANDLE ON THE
UPR JET LOCATIONS AND WL PUT SLGTLY MORE CONFIDENCE IN ITS SOLN.
HAVEN/T HAD THE CHC TO LOOK AT ANY 18Z GDNC...SO WL BASE FCST ON A
BLEND OF THE THREE 12Z MDLS.
THIS STRM HAS A FEW THINGS GOING FOR IT THO. NICE BAROCLINIC LEAF
APPARENT ON SAT PIX OVR ERN UT CORRESPONDS NICELY TO THE AREA OF
H5-H3 DIV-Q. SLOW MVMNT OF THIS UPR LOW ALG WITH STG UPSLOPE FLOW
THRU H6 WITH NELY WNDS OVR 25 KTS ARND H7 IS ALLOWING FOR RATHER
STUNNING MDL QPF OUTPUT. LIQUID EQIV STORM TOTALS THRU EARLY SAT
RANGE UP TO 3 INCHES FOR THE CWFA WITH THE HIGHEST AMTS OVR LARIMER
CO. THIS COULD BE TOO HIGH...BUT EVEN HALF OF THIS AMT WUD EQUATE
TO SOME PRETTY HVY SNOWFALL TOTALS IN THE FOOTHILLS. CANNOT RULE
OUT 1 TO 2 FT WITH LCLLY HIER AMTS ON THE E-FACING SLOPES IN ZN 35.
WITH THE EXCEPTION OF THE NGM...MDLS KP LWR LVLS CD ENUF FOR SNOW
ABV 5500 FEET OR SO. AM THINKING MOST PCPN WL FALL AS SNOW ACRS
METRO WITH LCL AMTS OF SVRL INCHES PSBL BY TMRW NGT. DEFINITELY HAS
THE POTENTIAL TO BE A VRY BAD SITUATION FOR THE TREES AND PWRLINES...
FRI WL BE SLGTLY WRMR BUT STILL WET AND CHILLY. BY SAT...THE SYS
SHUD BEGIN TO LIFT INTO THE GREAT PLAINS WITH DRY CONDITIONS
RETURNING BY SUN. 46
.DEN...WINTER STORM WARNING TONIGHT AND THURSDAY FOR THE NORTHERN
MOUNTAINS...FRONT RANGE FOOTHILLS...SOUTH PARK...AND
FORT COLLINS AREA...ZONES 30>38.
WINTER STORM WATCH TONIGHT AND THURSDAY FOR BOULDER AND DENVER
METRO AREAS...AND DOUGLAS AND ELBERT COUNTIES ABOVE 6000
FEET...ZONES 39>41.The national radar mosaic for the moment the first event began.
6 heavy snow. Local standard time, as filed.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2001Every state in 2001This day in weather historyWarnings in Colorado, May 2001
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: 5250052, 5250053, 5250054, 5250055, 5250056, 5250057.