Flood in Alaska, May 1 to 4, 2003

Name: Flood in Alaska, May 1 to 4, 2003
Start: 2003-05-01T00:00
End: 2003-05-04T16:00
Location: Alaska

May 1 to 4, 2003 · NWS AFG · 1 event in 1 county or zone

Event continued from April. Snowmelt and icemelt caused water to rise on the Tanana River and Piledriver Slough, and resulting in minor flooding of various properties beginning the night of the 25th.

The toll

Deaths: 0
Injuries: 0
Property damage: $2.0 million
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.

Event continued from April. Snowmelt and icemelt caused water to rise on the Tanana River and Piledriver Slough, and resulting in minor flooding of various properties beginning the night of the 25th. Ice buildup on roads and properties was created first by an Ice Jam event on the Tanana River during November 2002, and then surface water and groundwater flooding in early January 2003, resulting in up 2-foot thick layers of ice on the Old Richardson Highway and on properties near the Piledriver slough. On April 29th, another ice jam formed on the nearest branch of the Tanana River, next to the partial one that had formed and remained since November. This caused water from the Tanana River to flow into Piledriver Slough. The water in Piledriver Slough then went overbank and flooded properties and some homes, threatening other homes. By late afternoon on the 29th, water continued to rise breaching a dike on the Tanana River and rapidly raising water levels in the area. Water continued to rise into the beginning of May, flooding about 100 homes in all and threatening another 50 homes. The Old Richardson Highway was impassible, which is the main road serving many of the residents in this subdivision. During the first few days of May water levels fluctuated, but homes remained flooded or surrounded by water. On the morning of May 3rd, the Ice Jam shifted and gradually moved downstream, and water levels began dropping significantly. By late afternoon on May 4, the water was completely contained inside the Tanana River, and Piledriver Slough had also dropped significantly. Many surrounding areas still had ponded water due to the high groundwater level. The Fairbanks North Star Borough Department of Emergency Services and Salcha Rescue activated an Incident Command Center in the area and helped those residents requesting evacuation. Property Damage is an estimate. Event continued into May.

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 Apr 30, 1:30 PM AST, 10 hours 30 minutes earlier.

Area forecast discussion, Apr 30, 1:30 PM AST, 10 hours 30 minutes before

NORTH ALASKA FORECAST DISCUSSION
230 PM ADT WED APR 30 2003

500MB RIDGING IS SET TO DOMINATE THE WEATHER OVER NORTHERN ALASKA ONCE
AGAIN. GFS...ECMWF...AND UKMET ALL AGREE THAT THE 500MB RIDGE AXIS
EXTENDING FROM NEAR KODIAK ISLAND UP TO THE CHUKCHI SEA THIS AFTERNOON
WILL DEVELOP INTO A CUT OFF HIGH NORTHEAST OF WRANGEL ISLAND BY THURSDAY
NIGHT OR FRIDAY MORNING. THIS HIGH WILL THEN REMAIN QUASI-STATIONARY AND
BUILD TO THE AMAZING HEIGHT OF AROUND 5750 METERS BY SATURDAY. DESPITE
SOME RUN TO RUN INCONSISTENCIES IN THE MODELS...WILL BUY THIS BASIC
PATTERN FOR NOW.

ARCTIC COAST...WITH THE ATMOSPHERE DRY ABOVE THE LOW STRATUS DECK AND
TEMPERATURES IN THE CLOUD LAYER BETWEEN ZERO AND -10C...FREEZING DRIZZLE
IS A CONCERN FOR ZONES 201 AND 202. ONLY TRACE AMOUNTS OF PRECIPITATION
ARE POSSIBLE HERE...SO THERE IS NO THREAT FOR FREEZING RAIN WARNING.
EASTERN ARCTIC ZONES HAVE TOO MUCH MOISTURE AND DYNAMICS IN THE MIDDLE
LAYERS OF THE ATMOSPHERE TO ALLOW FREEZING DRIZZLE TONIGHT. IN THE
LONGER TERM...A SURFACE HIGH NOW BUILDING OVER THE NORTHERN INTERIOR
WILL DRIFT NORTH OVER THE NEXT 48 HOURS AS THE CUT-OFF 500MB HIGH
DEVELOPS. THE SURFACE HIGH WILL THEN DRIFT OFF SHORE OF THE ARCTIC COAST
BY FRIDAY AND PROVIDE AN EXTENDED PERIOD OF NORTHEASTERLY FLOW WHICH
COULD BRING BOUTS OF STRATUS AND FOG BUT NO SIGNIFICANT PRECIPITATION.

WEST COAST...A COMPARATIVELY QUIET PERIOD AHEAD AS THE 500MB PATTERN
PREVENTS ANY MAJOR NORTH PACIFIC STORMS FROM MOVING INTO THE NORTHERN
BERING SEA. PRIMARILY OFF SHORE FLOW AT THE SURFACE WILL HELP KEEP FOG
AND STRATUS FROM BECOMING A WIDESPREAD PROBLEM.

INTERIOR...DRY NORTHEASTERLY FLOW WILL BE THE RULE FOR SEVERAL DAYS AS
PROVIDED BY CONTRAST BETWEEN 500MB CUT-OFF HIGH NEAR WRANGEL ISLAND AND
LOW HEIGHTS OVER SOUTHEAST ALASKA. 500MB HEIGHTS WILL NOT BE
PARTICULARLY HIGH OVER THE INTERIOR...NOR WILL 1000-500MB
THICKNESSES...SO DO NOT EXPECT A REPEAT OF LAST WEEKENDS HEAT WAVE.

MAJOR ICE JAM FLOOD IN THE SALCHA AREA ALONG THE OLD RICHARDSON HIGHWAY
NOW APPEARS TO BE ABOUT AS BAD AS THE MAY 2002 FLOOD. THE TANANA RIVER
NEAR DELTA JUNCTION IS STILL RISING...AND THE ICE JAM NEAR THE OLD
BOONDOX BAR SITE APPEARS QUITE SOLID. A BREAK IN THE TANANA RIVER DIKE
IS ALLOWING WATER FROM THE TANANA RIVER TO FLOW DIRECTLY INTO THE
AFFECTED AREA. THIS ARRANGEMENT SHOULD LEAD TO CONTINUED SERIOUS
FLOODING FOR THE NEXT COUPLE OF DAYS AT LEAST.

ICE JAM FLOOD WATCH FOR THE CHATANIKA RIVER NEAR THE STEESE HIGHWAY
BRIDGE MAY BE CANCELLED WITH 400 PM ZONE ISSUANCE.

.AFG...WATCH/WARNING SUMMARY
PUBLIC...ICE JAM FLOOD WARNING FOR SALCHA AREA IN ZONE 222.
         ICE JAM FLOOD WATCH FOR UPPER CHATANIKA RIVER IN ZONE 222.
         FREEZING DRIZZLE ADVISORY ZONES 201 AND 202.
MARINE...SMALL CRAFT ADVISORY AREA 14.
         BRISK WIND ADVISORY AREAS 9B AND 11B.
FIRE WEATHER...NONE.

ES APR 03

Event by event

1 flood. Local standard time, as filed.

Flood, Deltana and Tanana

When: May 1, 12:00 AM AST to May 4, 4:00 PM AST
Where: Deltana and Tanana forecast zone
Property damage: $2.0 million
Reported by: EMERGENCY MANAGER

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 2003 Every state in 2003 This day in weather history Warnings in Alaska, May 2003

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: 5353973.