High pressure moved over northern Arizona in the wake of a strong cold front. The combination of cold dry air, low humidity, and no wind allowed temperatures to plummet.
Every event with a place to put it; 1 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 FGZ wrote it up.
High pressure moved over northern Arizona in the wake of a strong cold front. The combination of cold dry air, low humidity, and no wind allowed temperatures to plummet.
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 Flagstaff, AZ wrote its last area forecast discussion before the first event at Dec 15, 8:34 PM MST, 3 hours 26 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE FLAGSTAFF AZ 834 PM MST TUE DEC 15 2015 .SYNOPSIS...A VERY COLD AIR MASS WILL AFFECT NORTHERN ARIZONA THROUGH THURSDAY MORNING. A FEW LIGHT SNOW SHOWERS ARE POSSIBLE TONIGHT IN FAR NORTHEASTERN ARIZONA. WARMER TEMPERATURES SHOULD RETURN FROM THURSDAY THROUGH SATURDAY. ON SUNDAY...A WEAK COLD FRONT WILL BRING THE NEXT CHANCE OF PRECIPITATION. && .DISCUSSION...A VERY COLD NIGHT IS AHEAD FOR NORTHERN ARIZONA WITH A COLD AIR MASS IN PLACE AND LIGHT WINDS OVERNIGHT. THE CAVEAT FOR A FEW SPOTS WILL BE AREAS OF BROKEN STRATUS CLOUDS THAT HAVE DEVELOPED IN RESPONSE TO SOME WEAK TRAILING DISTURBANCES ROTATING THROUGH THE BASE OF THE TROUGH OVERHEAD. AREAS THAT SEE CLOUDS THIS EVENING MAY NOT BOTTOM OUT AT THEIR LOWEST POTENTIAL. OTHERWISE...OVERNIGHT LOWS EXPECTED TO BE IN THE SINGLE DIGITS AND LOW TEENS FOR MOST AREAS...WITH THE COLDEST HIGH ELEVATION VALLEYS DIPPING BELOW ZERO. A FEW TWEAKS MADE TO FORECAST CLOUD COVER WITH NO OTHER CHANGES. && .PREV DISCUSSION /340 PM MST/...A FEW INSTABILITY SHOWERS HAVE DEVELOPED TODAY, MAINLY OVER NORTHEAST ARIZONA AS ON LAST SHORTWAVE PASSES THROUGH. THESE SHOULD END AFTER SUNSET FOR MOST AREAS, BUT A SLIGHT CHANCE CONTINUES OVERNIGHT NEAR THE 4 CORNERS. SOME PATCHY FOG WAS INCLUDED IN THE FORECAST OVERNIGHT FOR MAINLY THE VALLEY AREAS NORTH OF THE MOGOLLON RIM. MORNING LOWS WEDNESDAY WILL BE RIGHT AROUND THE COLDEST SO FAR THIS SEASON FOR MOST OF THE AREA. WEDNESDAY LOOKING SUNNY BUT STILL COLD FOLLOWED BY ANOTHER BITTER NIGHT AND PATCHY FOG NORTH OF THE RIM. THURSDAY AND FRIDAY...A HIGH PRESSURE RIDGE BEGINS TO BUILD OVER THE AREA. DAYTIME TEMPERATURES TO SLOWLY MODERATE THURSDAY ACROSS THE HIGH COUNTRY BUT THE VALLEYS TO THE NORTHEAST OF THE MOGOLLON RIM SHOULD HAVE A SHALLOW TEMPERATURE INVERSION. WE MAY SEE SOME VALLEY FOG ACROSS THE NORTHEAST QUARTER OF THE STATE THURSDAY NIGHT AND FRIDAY. SATURDAY...AN APPROACHING LOW PRESSURE TROUGH WILL BRING INCREASING SOUTHWEST WINDS...WHICH WILL HELP BREAK UP VALLEY INVERSIONS. MAX TEMPS TO WARM TO A FEW DEGREES ABOVE NORMAL. SATURDAY NIGHT/SUNDAY...THE FIRST IN A SERIES OF LOW PRESSURE DISTURBANCES APPEARS TO PASS QUICKLY ACROSS THE AREA. AT THIS POINT IMPACTS LOOK MINOR. MONDAY AND TUESDAY, MODELS GENERALLY AGREE ON INCREASINGLY MOIST NORTHWEST FLOW THOUGH DETAILS REMAIN UNCERTAIN. WE KEPT A SLIGHT CHANCE OF SNOW/RAIN SHOWERS FOR THIS PERIOD. BEYOND THE 7 DAY FORECAST FOR MID TO LATE NEXT WEEK, ENSEMBLE FORECASTS ARE INDICATING A POSSIBLE WESTERN U.S. TROUGH WHICH COULD BRING UNSETTLED WEATHER TO NORTHERN AZ, STILL REALLY UNCERTAIN AT THIS POINT SO CHECK BACK FOR UPDATES FOR THE UPCOMING BUSY TRAVEL PERIOD. && .AVIATION...FOR THE 06Z PACKAGE...EXPECT SCT-BKN LOW CLOUDS OVER THE HIGHER TERRAIN WITH CIGS 4-6 KFT AGL. ISOLD -SHSN POSSIBLE OVER FAR NE AZ NEAR KRQE. PATCHY FREEZING FOG WILL DEVELOP AFTER 06Z ACROSS THE LITTLE COLORADO RIVER VALLEY NORTHEASTWARD TOWARDS THE FOUR CORNERS REGION. OTHERWISE VFR CONDITIONS CAN BE EXPECTED. AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS. && .FGZ WATCHES/WARNINGS/ADVISORIES...NONE. && PUBLIC...MCS/JJ AVIATION...MCS FOR NORTHERN ARIZONA WEATHER INFORMATION VISIT WEATHER.GOV/FLAGSTAFF
The national radar mosaic for the moment the first event began.
1 cold/wind chill. Local standard time, as filed.
The low temperature at the Flagstaff Airport was -6F and it was colder than 5F between midnight and 900 AM. Some outlying areas dropped down to between -14F (NWS Office) and -17F.
As the offices recorded each death: direct deaths were caused by the weather itself, indirect ones by something it set in motion.
| Event | Date | Age | Sex | Where | Kind |
|---|---|---|---|---|---|
| Cold/Wind Chill, Western Mogollon Rim | 2015-12-16 | Male | Outside/Open Areas | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Arizona in 2015Every state in 2015This day in weather historyWarnings in Arizona, 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: 605908.