Flood in Alaska, September 12 to 13, 2003

Name: Flood in Alaska, September 12 to 13, 2003
Start: 2003-09-12T05:00
End: 2003-09-13T09:00
Location: Alaska

September 12 to 13, 2003 · NWS AFG · 1 event in 1 county or zone

An inch of rain fell over the Chena Basin creating high water on the Chena River which produced minor flooding of Chena Hot Springs Road at mile 37.

The toll

Deaths: 0
Injuries: 0
Property damage: None recorded
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 inch of rain fell over the Chena Basin creating high water on the Chena River which produced minor flooding of Chena Hot Springs Road at mile 37.

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 Sep 12, 5:00 AM AST, 0 minutes earlier.

Area forecast discussion, Sep 12, 5:00 AM AST, 0 minutes before

NORTH ALASKA FORECAST DISCUSSION
600 AM ADT FRI SEP 12 2003

IT SEEMS AS THOUGH THE MODEL THAT INITIALIZED THE MOST ACCURATELY
WAS NGM. BUT BY 12Z SAT THE MODELS GENERALLY ARE BACK IN STEP WITH
EACH OTHER. ALL OF THE MODELS ARE IN TUNE WITH EACH OTHER WITH
CONTINUING THE SOUTHWEST TILTED LONG WAVE TROUGH OVER THE EASTERN
PART OF THE STATE THROUGH THE WEEKEND. THE WESTERN PART OF THE
STATE STILL HOLDS ONTO NORTHWEST FLOW BUT THE 500 HEIGHTS ARE
INCREASING SIGNIFICANTLY THROUGH THE WEEKEND AS THE OMEGA BLOCK
CONTINUES TO BUILD IN THE BERING SEA.

IN THE LONGER RANGE THE MODELS REMAIN CLOSE IN IDEA. ALTHOUGH THE
MRF AND ECMWF ARE 24 HOURS OLD..THEY ARE IN TUNE WITH THE NEW AVN
RUN. ALL ADVERTISING A RATHER SIGNIFICANT SHORT WAVE TO ROTATE
THROUGH THE LONG WAVE TROUGH WHICH WOULD PICK UP WINDS ON THE
ARCTIC COAST BY MONDAY NIGHT. THE MODELS STILL ARE IN PRETTY GOOD
AGREEMENT WITH WHAT TO DO WITH THE NORTH PACIFIC LOW. ALL OF THE
MODELS TAKE THE LOW AND SUCK IT INTO THE VERY ELONGATED LONG WAVE
TROUGH OVER THE EXTREME EASTERN PORTION OF THE STATE. THIS WOULD
ESSENTIALLY TILT THE BERING BLOCK TO CONTINUE TO DIRECT NORTHWEST
FLOW OVER MUCH OF THE STATE. HEIGHTS AT 500 ARE SIGNIFICANTLY HIGH
OVER AT LEAST THE WESTERN PART OF THE STATE.

ANOTHER HIGH ARCTIC LOW BEGINS MOVING SOUTHEAST OUT OF THE ARCTIC
BY MID WEEK BUT DOES NOT APPEAR AT LEAST PRESENTLY TO BE OF ANY
SIGNIFICANT DEPTH AS THE HEIGHTS ARE NOTHING TO WRITE HOME ABOUT.

ARCTIC COAST...SIGNIFICANT WARM ADVECTION WILL BEGIN AFFECTING THE
ARCTIC COAST FROM BARROW WESTWARD BY THE END OF THE WEEKEND. HIGH
PRESSURE CONTINUES TO BUILD IN. AS THE 850 TEMPERATURES BEGIN TO
RISE...SNOWSHOWERS WILL DIMINISH AS THE WATER TO 850 TEMPERATURE
GRADIENT DECREASES SUBSTANTIALLY. HOWEVER THE EASTERN ARCTIC COAST
WILL STILL SEE THE OCCASIONAL SNOW SHOWERS.

WEST COAST...CLOUDS AND RAIN SHOWERS WILL CONTINUE TO DISSIPATE
THROUGHOUT TODAY AS HIGH PRESSURE BUILDS OVER THE WESTERN ARCTIC
COAST. A SHORT WAVE ROTATES INTO THE NORTHWESTERN PART OF THE
STATE ON SUNDAY NIGHT WHICH MAY DROP A FEW SPRINKLES AND FLURRIES
OVER THE AREA FROM KOTZEBUE NORTH. THE SOUTHERN PART OF THE WEST
COAST SHOULD REMAIN PRECIPITATION FREE.

INTERIOR...A BATCH OF CLOUDS CONTINUES TO WORK ITS WAY THROUGH THE
NORTHERN INTERIOR TODAY AND SLOWLY DROPS SOUTHWARD OVER THE
EASTERN INTERIOR AS IT ROTATES THROUGH THE LONG WAVE TROUGH. HIGH
PRESSURE BUILDS IN OVER THE INTERIOR AND HAS ALLOWED THE INTERIOR
TEMPERATURES TO FINALLY PLUNGE AS THE CLOUDS MOVE OUT AND MINUS
EIGHT TO MINUS TEN 850 TEMPERATURES ENGULF THE EASTERN INTERIOR.

.AFG...WATCH/WARNING SUMMARY
PUBLIC...NONE.
MARINE...NONE.

CF SEP 03

Event by event

1 flood. Local standard time, as filed.

Flood, Middle Tanana Valley

When: September 12, 5:00 AM AST to September 13, 9:00 AM AST
Where: Middle Tanana Valley forecast zone
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 2003 Every state in 2003 This day in weather history Warnings in Alaska, September 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: 5336857.