Flood in Alaska, May 17 to 19, 2006

Name: Flood in Alaska, May 17 to 19, 2006
Start: 2006-05-17T19:30
End: 2006-05-19T15:00
Location: Alaska

May 17 to 19, 2006 · NWS AFG · 1 event in 1 county or zone

An ice jam formed on the Yukon River 20 miles downstream of Nulato causing flooding of the village of Nulato and Koyukuk. In Nulato, a number of roads were impassable during the flooding, including the road to the airport.

The toll

Deaths: 0
Injuries: 0
Property damage: $280,000
Crop damage: None recorded
Events: 1

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.

What happened

The episode as NWS AFG wrote it up.

An ice jam formed on the Yukon River 20 miles downstream of Nulato causing flooding of the village of Nulato and Koyukuk. At Nulato the water reached maximum height at 0500 ADT on the morning of the 19th....reaching a marking of 2.2 on the Corps of Engineers gage.In Nulato, a number of roads were impassable during the flooding, including the road to the airport. In Koyukuk, most of the roads were flooded; access to homes, city buildings, and the school was restricted. By 1300 ADT on the 19th water levels had fallen such that most buildings were accessible. 32 residents were flown out to the bigger village of Galena on the 18th and 19th, returning on the 24th and 25th after preliminary water testing showed that the contaminants in the water system had been reduced to safe levels. Very early on the 19th, a woman and her three children, camping about 6 miles upriver from Koyukuk were rescued by an Army medevac helicopter crew when they became stranded due to the high water.Monetary amount of damage was $32,000 in Nulato and $248,100 in Koyukuk.

What forecasters said that day

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 Fairbanks, AK wrote its last area forecast discussion before the first event at May 17, 12:36 PM AST, 6 hours 54 minutes earlier.

Area forecast discussion, May 17, 12:36 PM AST, 6 hours 54 minutes before

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
136 PM ADT WED MAY 17 2006

.DISCUSSION...SHORT TERM...TONIGHT THROUGH FRIDAY NIGHT. LATEST WATER
VAPOR IMAGERY SHOWS AN UPPER LOW SPINNING OVER THE BERING SEA AT
62N/176W. SEVERAL SHORTWAVES WERE SEEN ROTATING AROUND LOW AND
PIVOTING TOWARD THE WESTERN COASTAL ZONES. WILL LET CURRENT BRISK
WIND ADVISORY FOR WESTERN COASTAL MARINE ZONE 210 CONTINUE INTO
THURSDAY MORNING. ALSO HIGH PRESSURE OVER THE ARCTIC OCEAN STILL
PROVIDING FOR A TIGHT GRADIENT OVER THE NORTHERN SLOPE MARINE
ZONES 240/245...AND WILL ALSO LET THIS RIDE INTO THURSDAY
MORNING. FURTHER INLAND...AN UPPER LOW OVER ZONE 224 CONTINUES TO
CIRCULATE CLOUDS/SCATTERED SHOWERS BACK ACROSS THE TANANA VALLEY.
ETA AND GFS INITIALIZE THIS FEATURE WELL AND BOTH ROTATE UPPER LOW
INTO THE NORTHERN SLOPE ZONES BY 00Z FRI. TIME HEIGHT/X-SECTIONS
OVER FAIRBANKS SHOW OMEGA MAXES PEAKING OVERNIGHT THEN WANING ON
THURSDAY WITH THE DEPARTURE OF THE UPPER LOW AND ASSOCIATED
DYNAMICS. THE RESULT WILL BE FOR SCATTERED SHOWERS TONIGHT
BECOMING ISOLATED ON THURSDAY. AFOREMENTIONED UPPER LOW OVER THE
BERING SEA BRINGS A WEAKENING SHORTWAVE TROUGH THROUGH THE TANANA
VALLEY THURSDAY INTO FRIDAY. ONLY A VERY WEAK SFC REFLECTION WITH
THIS SYSTEM SO PRECIP EXPECTED TO REMAIN VERY LIGHT AND SPOTTY.
MAIN TROUGH APPROACHES THE SOUTHWEST COASTAL ZONES WITH WELL
DEVELOPED SFC FRONTAL SYSTEM FRI EVE/NIGHT WITH POTENTIAL FOR A
WIDESPREAD PRECIPITATION EVENT.

.EXTENDED...SATURDAY THROUGH WEDNESDAY. ETA AND GFS DIFFER
SIGNIFICANTLY ON POSITION OF SFC FRONTAL POSITION AND PRECIP AREA BY
00Z SUN. ETA KEEPS SFC LOW AND PRECIP IN/AROUND THE BRISTOL BAY
AREA WHILE THE GFS SCOOTS THE SFC LOW TO KODIAK ISLAND. PRECIP
PATTERN MUCH FURTHER SOUTH AND EAST WITH GFS TRACK VERSUS ETA.
HOWEVER THE GFS AND ECMWF ARE IN GOOD AGREEMENT ON STRENGTH AND
POSITION OF UPPER TROUGH OVER WRANGEL ISLAND SUPPORTING
AFOREMENTIONED SFC FRONT. TROUGH ELONGATES AND SPLITS APART ON SAT
WITH RIDGING DEVELOPING OVER THE BERING SEA INTO THE ALASKAN
INTERIOR. THIS SHOULD BRING A PERIOD OF DRIER WEATHER MON INTO WED
OVER MOST ZONES.

.FIRE WEATHER...RED FLAG WARNING WILL BE CANCELED DUE TO
WEAKENING WINDS AND HIGHER RELATIVE HUMIDITIES. NO FIRE WEATHER
CONCERNS FOR THURSDAY AT THIS TIME.

.HYDRO...THE FLOOD POTENTIAL IS LOW OVER ALASKA WITH ONLY LIGHT
RAINS EXPECTED OVER THE NEXT COUPLE OF DAYS. NO HYDRO CONCERNS ARE EXPECTED.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
BRISK WIND ADVISORY FOR PKZ210-PKZ240-PKZ245.
&&

KS/TS/JMA/RL/SDB/MAR MAY 06

Event by event

1 flood. Local standard time, as filed.

Flood, Lower Koyukuk Middle Ykn Vlys

When: May 17, 7:30 PM AST to May 19, 3:00 PM AST
Where: Lower Koyukuk Middle Ykn Vlys County, Koyukuk
Property damage: $280,000
Reported by: OFFICIAL NWS OBS.

What these are

Flood: Flooding that develops more slowly than a flash flood: rivers leaving their banks, or water standing over land for an extended time.

After NWS Directive 10-1605, the rules offices file Storm Data by.

The same day elsewhere

Every storm in Alaska in 2006 Every state in 2006 This day in weather history Warnings in Alaska, May 2006

Sources

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: 5512448.