A weather disturbance that brought cold air in a northwesterly flow produced significant snowfall in some mountain areas of northwest Colorado.
Every event with a place to put it; 3 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 weather disturbance that brought cold air in a northwesterly flow produced significant snowfall in some mountain areas of northwest Colorado.
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 Dec 16, 3:53 AM MST, 5 hours 7 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE GRAND JUNCTION CO 353 AM MST WED DEC 16 2015 .SHORT TERM...(TODAY THROUGH THURSDAY) ISSUED AT 351 AM MST WED DEC 16 2015 COLD AIR REMAINS IN PLACE TODAY WITH COLDER AIR ON THE WAY FOR TONIGHT AND THURSDAY. THERE IS LITTLE DYNAMICAL SUPPORT TODAY BUT THE DENDRITIC CRYSTAL GROWTH REGION IS WITHIN THE 700-600MB LAYER AT MTN TOP LEVEL. NEAR SATURATION WITHIN THIS LAYER OVER THE NORTHERN AND CENTRAL COLORADO MTNS WILL KEEP IN LOW CLOUDS AND LIGHT SNOW SHOWERS. TONIGHT...A WAVE IN NW FLOW BRINGS JET SUPPORT AND IMPRESSIVE COLD ADVECTION. 500MB TEMPERATURES DROP FROM -26C TODAY TO -35C ACROSS THE NORTH BY THURSDAY MORNING. THIS IS THE COLDEST AIR THAT WE HAVE SEEN SO FAR THIS SEASON. THIS SYSTEM WILL EFFICIENTLY PRODUCE SNOWFALL WITH 4-8 INCHES EXPECTED OVER THE NW COLORADO MTNS WITH 12 INCH ACCUMULATIONS POSSIBLE. THE HEAVIEST SNOW IS EXPECTED BETWEEN MIDNIGHT AND SUNRISE WITH SNOWFALL DIMINISHING THURSDAY AFTERNOON. .LONG TERM...(THURSDAY NIGHT THROUGH TUESDAY) ISSUED AT 351 AM MST WED DEC 16 2015 HEIGHT RISES INDICATE HIGH PRESSURE BUILDING IN THURSDAY NIGHT BUT LATEST GUIDANCE SUGGESTING PRECIP WILL MAKE IT UP AND OVER THE RIDGE AND DROP DOWN CAUSING SOME LIGHT SNOWFALL FOR THE NORTHERN MTNS. THIS WILL BE MORE NUISANCE SNOW WITH MORE FLURRIES AND SNOW SHOWERS AS OPPOSED TO A STEADY SNOWFALL. THE REST OF THE CWA WILL SEE TIMES OF SUN AND CLOUDS FAVORING MORE SUNNY CONDITIONS. TEMPERATURES WILL CONTINUE THEIR SLOW WARMUP BUT AGAIN...MODELS PROBABLY NOT TAKING INTO ACCOUNT VALLEY INVERSIONS SO DROPPED HIGH TEMPS SEVERAL DEGREES. FOR SATURDAY...SUNNY SKIES EXPECTED AS THE RIDGE SHIFTS EAST ALLOWING WINDS TO SHIFT TO THE SOUTHWEST BRINGING IN SOMEWHAT WARMER CONDITIONS. WARMEST CONDITIONS WILL BE ABOVE THE INVERSIONS SO GO TO THE MOUNTAINS TO WARM UP...A LITTLE UNINTUITIVE BUT TRUE JUST THE SAME. DURING THIS TIME PERIOD...A TROUGH COMES ASHORE OVER THE CALIFORNIA COAST BUT WEAKENS AS IT APPROACHES AND BECOMES MORE A OF BLIP IN THE MEAN FLOW. THE BLIP MOVES OVER SUNDAY AND WILL BRING SOME LIGHT PRECIP ALONG THE WY/CO BORDER BUT NOTHING TOO IMPRESSIVE. CLOUDS WILL ALSO INCREASE AS IT MOVES OVERHEAD. MONDAY AND BEYOND GETS VERY INTERESTING. INTERESTING BECAUSE IT LOOKS LIKE THE JET STREAM WILL SET UP OVER THE PACNW WITH THE EXIT REGION REMAINING OVER OUR FORECAST AREA FOR THE WEEK. GUIDANCE HIGHLIGHTS DISTURBANCES MOVING OVER UTAH AND COLORADO JUST ABOUT EVERY 24 HOURS...SOME BEING MORE PRONOUNCED THAN OTHERS...WITH UNSETTLED WX CONTINUING AS ONE SYSTEM MOVES OUT AND ANOTHER DROPS DOWN FROM THE NORTHWEST. THIS PROGRESSIVE PATTERN BEGINS MONDAY AS A RELATIVELY WEAK WAVE MOVES IN...FOLLOWED BY A STRONGER WAVE TUESDAY...ANOTHER WEDNESDAY..AND ANOTHER THURSDAY NIGHT. IT'S QUITE REMARKABLE. THE EC ALSO SHOWING UNSETTLED WX BUT WITH TIMING AND INTENSITY DIFFERENCES. RAIN AND SNOW CERTAINLY EXPECTED FOR MUCH OF THE WEEK. IF TRAVELLING...PLEASE STAY ABREAST OF THE LATEST FORECAST BECAUSE IT WILL CHANGE AS WE GET CLOSER TO THE EVENT. SOME SIGNIFICANT TRAVEL DIFFICULTIES ARE CERTAINLY POSSIBLE NEXT WEEK. AGAIN...AS THIS IS 5 DAYS OUT...FORECAST CHANGES WILL OCCUR AND SHOULD BE MONITORED. && .AVIATION...(FOR THE 12Z TAFS THROUGH 12Z THURSDAY MORNING) ISSUED AT 351 AM MST WED DEC 16 2015 -SN CONTINUES AT THIS HOUR FOR THE NORTHERN MTNS AND VICINITY THANKS TO FAVORABLE NW FLOW. MVFR IS COMMON AND WILL LIKELY REMAIN SO FOR KSBS AND KHDN THROUGH 15Z OR SO BEFORE BECOMING MORE VFR. KEEO AND KCAG WILL VARY FROM MVFR TO VFR FOR THE MORNING HOURS. KTEX IS ALSO SEEING OCCNL -SN AT THIS HOUR WITH LOW VIS BEING REPORTED. MIDLEVEL CLOUDS ALSO BEING REPORTED AT MANY TAF SITES AS CLOUDS CONTINUE TO STREAM DOWN FROM THE NORTHWEST. EXPECT THESE CLOUDS TO HANG AROUND FOR MUCH OF THE DAY THOUGH THEY'LL LIFT SOME AS THE DAY PROGRESSES. && .GJT WATCHES/WARNINGS/ADVISORIES... CO...WINTER STORM WARNING UNTIL 9 AM MST THIS MORNING FOR COZ004-005. UT...NONE. && SHORT TERM...JOE LONG TERM...TGR AVIATION...TGR
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
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
733 AM MST WED DEC 16 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0719 AM HEAVY SNOW MCCLURE PASS 39.09N 107.28W
12/16/2015 M18.0 INCH GUNNISON CO CAIC
STORM TOTAL SNOWFALL
&&
EVENT NUMBER GJT1501621
DCPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND JUNCTION CO
734 AM MST WED DEC 16 2015
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0725 AM HEAVY SNOW GRAND MESA 39.05N 107.87W
12/16/2015 M18.0 INCH DELTA CO CAIC
STORM TOTAL SNOWFALL
&&
EVENT NUMBER GJT1501622
DCThe national radar mosaic for the moment the first event began.
3 winter weather. Local standard time, as filed.
Snowfall amounts of 5 to 9 inches were measured across the area. Locally higher amounts of 13 and 15 inches were measured at the Whiskey Park and Tower SNOTELs, respectively.
Snowfall amounts of 5 to 8 inches were measured across the area.
Snowfall amounts of 3 to 6 inches were measured across the area.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Colorado in 2015Every state in 2015This day in weather historyWarnings in Colorado, December 2015
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: 659899, 659901, 659900.