High pressure over the Interior brought a dome of cold air south of the Alaska Range, while a low pressure system in the northern Gulf brought several waves of moisture onshore. These two factors combined to deposit 14 inches of snow in Hatcher Pass.
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 AFC wrote it up.
High pressure over the Interior brought a dome of cold air south of the Alaska Range, while a low pressure system in the northern Gulf brought several waves of moisture onshore. These two factors combined to deposit 14 inches of snow in Hatcher Pass. Although the snowfall was not unusual, it placed increased stress on a weak layer in the snow pack from earlier in the season, thus increasing the avalanche danger.
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 Anchorage, AK wrote its last area forecast discussion before the first event at Mar 9, 3:42 PM AKST, 2 hours 18 minutes earlier.
Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 442 PM AKDT Mon Mar 9 2020 .ANALYSIS AND UPPER LEVELS... There is a north to south oriented upper level trough over Alaska that is slowly moving eastward. There is a somewhat flat ridge over the central and western Bering, with another trough near the Kamchatka Peninsula. At the surface there is a low along the north Gulf coast, with high pressure over mainland Alaska. There is weak offshore flow over Southcentral, with stronger northerly flow over Southwest Alaska. A southward moving surface trough is just south of the Alaska Peninsula and eastern Aleutians, with brisk northerly flow to the north of that trough. Some snow and snow showers are occurring over Southcentral ahead of the upper trough axis. There are also some showers over the Alaska Peninsula and eastern Aleutians. && .MODEL DISCUSSION... The numerical models are in good agreement through Wednesday afternoon. There are some minor differences on moisture and precipitation for the early portion of the forecast. Forecast confidence is higher than normal today. && .AVIATION... PANC...Occasional MVFR conditions are possible this evening in lingering snow showers, otherwise VFR conditions are expected. Northerly winds will increase this evening, then diminish late tonight. && .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2)... An upper trough over western AK continues to slowly push east, while a deformation zone on the backside of an associated surface low near Prince William Sound continues to bring areas of light snow to Southcentral. Snow will taper off tonight in the Anchorage Bowl and Mat-Su Valleys, and ramp up a bit in the Copper River Basin as the low steers east. As the parent upper trough dives southeastward tonight into Tuesday, expect a transition to cold, dry conditions from west to east. Expect strong offshore winds out of the usual gaps and passes driven by a strong pressure gradient between cold dense air inland and lower pressure offshore. Winds will initially ramp up tonight over the Barren Islands, then gusty winds will set in in Whittier/Passage Canal by early Tuesday morning. Valdez waterways and Thompson Pass winds will ramp up during the day Tuesday. Expect gusts around 60 mph through Thompson Pass Tuesday afternoon, causing visibility reductions from blowing snow. Winds will diminish Wednesday as the Arctic high becomes centered over the Alcan border and the surface low in the Gulf exits to the east. Upper ridging will build in over the Bering, maintaining dry, quiet weather over Southcentral Wednesday into Thursday. && .SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3: tonight through Thursday)... Quiet weather will persist for Southwest AK the next few days. It will be clear and cold through midweek with northerly drying flow in place. Wind direction will switch Thursday to the southwest, which will warm temperatures and bring in cloud cover from the Bering Sea. This is due to a front approach in the central Bering. However, high pressure to the east will hold off any weather from reaching the coast, keeping weather quiet. We are confident in this forecast. && .SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 3: tonight through Thursday)... The next couple of days the big weather story is northerly cold air pushing through the Eastern Aleutians creating gusty winds through bays and passes. This is also creating heavy freezing spray in areas of gusty winds. The eastern Bering then quiets Wednesday into Thursday. During this time a low pressure system enters the Bering from the west. Model runs showed this low coming in stronger today and setup looks favorable for storm force winds, so we did increase this low to a storm force today. Winds will likely need to be adjusted over the next couple of days, but anticipate it to stay storm force strength. High pressure over Interior AK will prevent this low from working eastward to the coast. We have moderate to high confidence in the forecast. && .MARINE (Days 3 through 5/Wednesday through Friday)... Gusty northerly gap winds along the Alaska Peninsula and the Gulf Coast are expected for much of Wednesday. Some of the stronger winds will be around the Barren Islands, Resurrection Bay, and the Copper River Delta. Winds will taper west to east Wednesday midday through the evening hours as high pressure builds in and pressure gradients weaken. A strong front enters the western Aleutians Wednesday afternoon and is expected to bring storm force winds to the western Bering and the western extremity of the Aleutians Wednesday night. Winds diminish some by Thursday midday, but an area of storm force winds west of St Matthew Island and north of 56N is expected through that time. As this front weakens Thursday evening, a period of relatively quiet weather is expected through Friday. && .LONG TERM FORECAST (Days 3 through 7/Wednesday through Sunday)... Wednesday will see the start of a quiet weather period with much of Southcentral Alaska seeing their first sunny skies in a bit. Clearing skies and northerly winds will bring back colder temperatures to end the work week. High temperatures will rebound over the weekend as high pressure dominates southern Alaska. Weather across much of the Bering will be relatively quiet to start the period. A storm force front will bring some strong winds to the Western Aleutians Wednesday night and spread across the Western Bering, before diminishing early Friday morning. A north Pacific low will approach the eastern Aleutians Thursday night, but model confidence is low on its impact to the area. Aside from this system, weather for the remainder of the weekend will remain quiet in and around the Bering Sea. && .AFC WATCHES/WARNINGS/ADVISORIES... PUBLIC...NONE. MARINE...Gales 121 127-132 138 150 155 172 178 FIRE WEATHER...NONE. && SYNOPSIS AND MODEL DISCUSSION...BL SOUTHCENTRAL ALASKA...MM SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...BB MARINE/LONG TERM...LB
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
155 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0154 PM SNOW 1 W PALMER 61.60N 149.13W
03/09/2020 M3.0 INCH MATANUSKA-SUSITNA AK NWS EMPLOYEE
3 INCHES SINCE 7AM MONDAY MORNING. MODERATE
TO HEAVY SNOWFALL OCCURRING AT 1:40PM.
&&
KOPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
310 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0309 PM SNOW 10 MILES SE 61.10N 149.78W
03/09/2020 E1.0 INCH ANCHORAGE AK TRAINED SPOTTER
&&
KOPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE ANCHORAGE AK
314 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0154 PM SNOW 1 W PALMER 61.60N 149.13W
03/09/2020 M3.0 INCH MATANUSKA-SUSITNA AK NWS EMPLOYEE
3 INCHES SINCE 7AM MONDAY MORNING. MODERATE
TO HEAVY SNOWFALL OCCURRING AT 1:40PM.
0309 PM SNOW 10 MILES SE 61.10N 149.78W
03/09/2020 E1.0 INCH ANCHORAGE AK TRAINED SPOTTER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
345 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0317 PM SNOW SUTTON 61.71N 148.87W
03/09/2020 M3.5 INCH MATANUSKA-SUSITNA AK TRAINED SPOTTER
CURRENTLY SNOWING, TEMPERATURE OF 32.
&&
KOPRELIMINARY LOCAL STORM REPORT...SUMMARY
NATIONAL WEATHER SERVICE ANCHORAGE AK
346 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0317 PM SNOW SUTTON 61.71N 148.87W
03/09/2020 M3.5 INCH MATANUSKA-SUSITNA AK TRAINED SPOTTER
CURRENTLY SNOWING, TEMPERATURE OF 32.
0154 PM SNOW 1 W PALMER 61.60N 149.13W
03/09/2020 M3.0 INCH MATANUSKA-SUSITNA AK NWS EMPLOYEE
3 INCHES SINCE 7AM MONDAY MORNING. MODERATE
TO HEAVY SNOWFALL OCCURRING AT 1:40PM.
0626 PM SNOW 5 NNW HOMER 59.70N 151.59W
03/08/2020 M3.0 INCH KENAI PENINSULA AK CO-OP OBSERVER
0309 PM SNOW 10 MILES SE 61.10N 149.78W
03/09/2020 E1.0 INCH ANCHORAGE AK TRAINED SPOTTER
&&PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ANCHORAGE AK
456 PM AKDT MON MAR 9 2020
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0455 PM SNOW 5 ENE BIG LAKE 61.56N 149.84W
03/09/2020 M25.0 INCH MATANUSKA-SUSITNA AK NWS EMPLOYEE
STORM TOTAL.
&&
KO1 avalanche. Local standard time, as filed.
Hatcher Pass Avalanche Center reported an avalanche on Mile 16 of Palmer Fishhook Rd. A 17 year old snowboarder was rescued, but later perished at the hospital.
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 |
|---|---|---|---|---|---|
| Avalanche, Matanuska Valley | 2020-03-09 | 17 | Male | Outside/Open Areas | Direct |
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Alaska in 2020Every state in 2020This day in weather historyWarnings in Alaska, March 2020
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: 871648.