Alaska flood warning issued as warm winter temperatures melt ice

National Weather Service (NWS) meteorologists in Anchorage, Alaska, are warning of floods as above-normal winter temperatures contribute to ice melt.

Average high temperatures for this time of year in Anchorage are around the mid-20s, NWS meteorologist Joshua Ribail told Newsweek, but a ridge of high pressure to the east has contributed to higher temperatures as warm air draws into Alaska from the south. The unseasonable temperatures have various impacts, including the risk of river flooding as ice melts.

“Recent warm temperatures have melted portions of the ice cover across south central Alaska, causing ice movement and some ice jams,” a hydrologic outlook from NWS Anchorage said.

“Temporary rises along area rivers and minor flooding of lowland locations are possible through Thursday, ahead of a colder airmass returning to south central Alaska. As colder air filters in by late Wednesday into Thursday, high water and ice action should subside.”

Data from Processed Webdata by Pricing Culture sourced from the NWS and provided to Newsweek revealed that with a high near 38 degrees Fahrenheit expected on Wednesday, Anchorage’s temperatures are more than 13 degrees above the five-year historical average.

“Anchorage is experiencing warmer than average temperatures, with a deviation of 13.2 F from the five-year historical average,” a statement with the data said.

“This is a significant increase of 65.02 percent from the average temperature on this day. The increased precipitation in the next 24 hours, with a 62 percent chance, is also noteworthy. The NWS has issued a Hydrologic Outlook warning of potential ice jams and flooding due to recent warm temperatures and melting ice cover.”

Precipitation is likely over the next three days, the statement said, which could contribute to flood concerns.

“Overall, the weather in Anchorage is expected to be wet and potentially icy, with a high chance of precipitation and a risk of flooding due to ice jams,” it said.

On Tuesday, the high temperature in Anchorage was 47 F, which broke the daily high record for the city. The previous record for December 10 was 46 F.

In a post on X, formerly Twitter, the NWS Anchorage forecast office shared the expected temperatures for the next few days. Temperatures will remain in the 30s through Thursday. By Friday, they will start to fall into the upper 20s. By Sunday morning at 3 a.m. local time, the temperatures are expected to dip below 20 degrees.

Despite the return of colder temperatures, the NWS Climate Prediction Center anticipates that temperatures in Alaska will remain above normal through at least December 24, according to the eight- to 14-day temperature outlook. The highest chance at warmer temperatures will likely occur in south central and southeastern Alaska, the outlook showed.

After the cooldown over the weekend and into next week, Ribail said warm temperatures will return.

However, the three-month outlook shows colder-than-normal temperatures across southern Alaska, signifying that the state could soon see the return of frigid weather.