A moist southwesterly flow ahead of an upper level low pressure system brought heavy snow to the southwest San Juan Mountains. Snowfall amounts varied from 10 to 14 inches and combined with winds gusting to over 60 mph to produce widespread blowing and drifting snow.
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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 GJT wrote it up.
A moist southwesterly flow ahead of an upper level low pressure system brought heavy snow to the southwest San Juan Mountains. Snowfall amounts varied from 10 to 14 inches and combined with winds gusting to over 60 mph to produce widespread blowing and drifting snow.
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 Grand Junction, CO wrote its last area forecast discussion before the first event at Apr 5, 1:26 PM MST, 6 hours 34 minutes earlier.
WESTERN COLORADO & EASTERN UTAH AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
226 PM MDT THU APR 5 2001
PACIFIC CONNECTION IN PLACE AS DEPICTED BY SATELLITE IMAGERY EARLY
THIS AFTERNOON. LOOK OUTSIDE SHOWED MOISTURE BEGINNING TO FILL IN AT
LOWER LEVELS WITH SOME MOUNTAIN SHOWERS ALREADY BEGINNING ACCORDING
TO KGJX RADAR.
MODELS CONTINUE TO TELL THE SAME STORY TODAY...BRINGING PACIFIC STORM
SYSTEM ACROSS THE SOUTHWEST OVERNIGHT THEN OVER THE CWFA FRIDAY.
HARD TO FIND A SIGNIFICANT DIFFERENCE BETWEEN THE AVN AND ETA...BUT
DID NOTICE THAT THE AVN SEEMED TO HAVE A SOMEWHAT BETTER HANDLE ON
THE PACIFIC MOISTURE PLUME. THEREFORE...NEAR TERM FORECAST WILL BE
BASED ON THE AVN THIS PERIOD.
SEEMS PRETTY CLEAR THAT THE WATCH FOR CO ZONE 19 WILL HAVE TO BE
UPDATED. ALL THE INGREDIENTS FOR A SIGNIFICANT DUMPING APPEAR TO BE
IN PLACE. DIVERGENCE ASSOCIATED WITH CYCLONICALLY CURVED 130 KNOT JET
WILL AID OROGRAPHIC LIFT PROVIDED BY STRONG SOUTHERLY FLOW AT 7H.
RHEA THALER MODEL SHOWED FROM 6 TO 12 INCH ACCUMULATIONS POSSIBLE...
AND WITH INSTABILITY AND DEEP MOISTURE COMBINED WITH THE PREVIOUSLY
MENTIONED UPWARD FORCING MECHANISMS...THIS APPEARS REASONABLE. WILD
CARD IS THE TIME OF YEAR...WITH WET BULB ZERO INITIALLY INDICATED
NEAR THE 10K FOOT MARK. HOWEVER...AS THE COLD AIR WORKS IN OVERNIGHT
...EXPECT SNOW LEVELS WILL DROP. THEREFORE...WILL HOLD ONTO MENTION
OF BEST ACCUMULATIONS ABOVE 8500 FEET.
CO ZONES 9...12 AND 18 ALSO TO RECEIVE GOOD AMOUNTS OF SNOWFALL...
MUCH OF WHICH WILL COME ON FRIDAY AS FLOW SHIFTS TO THE WEST AND
INCREASES. HOWEVER...EXPECT AMOUNTS TO REMAIN BELOW WARNING CRITERIA
(6 TO 11 INCHES ACCORDING TO RHEA-THALER)...THEREFORE WILL GO WITH
SNOW AND BLOWING SNOW ADVISORY FOR THOSE ZONES. ALSO REQUIRING
MENTION ARE THE NORTHERN CO MOUNTAIN ZONES (4...10 AND 13) WHERE
INSTABILITY AND STRONG WEST FLOW COULD BRING ABOUT RAPID BUILD UP OF
SNOW POSSIBLY APPROACHING THE ONE FOOT MARK BY SATURDAY MORNING.
THEREFORE...IN COORDINATION WITH BOU...WILL GO WITH WINTER STORM
WATCH FOR THOSE ZONES TONIGHT. MEANWHILE...LOWER ELEVATIONS WILL
SEE EXCELLENT CHANCE FOR RAIN WITH RAIN CHANGING OVER TO SNOW AT
HIGHER ELEVATIONS TONIGHT...WITH MAINLY RAIN TOMORROW.
FLOW BACKS TO THE SOUTHWEST FOR SATURDAY AND SATURDAY NIGHT WITH
JET COMING DIRECTLY OVERHEAD. THEREFORE...WILL CONTINUE TO CARRY WET
FORECAST INTO THE EARLY PART OF THE WEEKEND.
.EXTENDED...RUN TO RUN CONSISTENCY GOOD BETWEEN THE MRF...ECMWF AND
UKMET THIS MORNING. MODELS CONTINUE TO SHOW DEEP WESTERN TROF
REPLACING SYSTEM DISCUSSED ABOVE THIS WEEKEND. DIFFERENCE IS THAT
EC IS A BIT DEEPER AND FARTHER WEST THAN MRF...AND LIKE YESTERDAY...
STILL FAVOR THIS SOLUTION. NOTICED THAT A LITTLE BIT MORE ENERGY
TO AFFECT THE NORTHWEST PORTION OF THE CWFA EARLY IN THE WEEK...SO
WILL BACK OFF OF DRY FORECAST FOR THOSE AREAS. MEANWHILE...MRF
CONTINUES IDEA OF BRINGING ANOTHER COLD FRONT ACROSS THE NORTH ON
SATURDAY. EC DOES SO A DAY LATER...THOUGH NOT QUITE AS COLD. AS A
RESULT...WILL CONTINUE TO SPLIT THE DIFFERENCE. MEANWHILE...THE
REMAINDER OF THE CWFA LIKELY TO SEE CONDITIONS MUCH LIKE THE AREA HAS
SEEN OVER THE PAST SEVERAL DAYS. BY MIDWEEK...MODELS BRING TROF
ACROSS THE REGION...SO WILL BRING ANOTHER CHANCE FOR SHOWERS AND
SOMEWHAT COOLER TEMPERATURES.
COORDINATION WITH BOU AND PUB.
NL
.GJT...WINTER STORM WARNING TONIGHT AND gFRIDAY CO ZONE 19.
SNOW AND BLOWING SNOW ADVISORY CO ZONES 9...12...18
TONIGHT AND FRIDAY.
WINTER STORM WATCH FRIDAY AND FRIDAY NIGHT CO ZONES
4...10 AND 13.The national radar mosaic for the moment the first event began.
1 winter storm. 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, April 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: 5242466.