MAT-SU — A Special Weather Statement has been issued for the Matanuska Valley by the National Weather Service in Anchorage. The statement warns of high rivers and possible bank erosion along streams due to sustained high temperatures.
“Warm temperatures and freezing levels 9,000-11,000 feet through the middle of this coming week will increase glacier and high elevation snowmelt on the Matanuska River and other predominantly glacier fed rivers in the Matanuska Valley. High River levels on the Matanuska River will increase bank erosion,” reads the statement.
While temperatures have been noticeably high this summer, the conditions that have led to the heat are not uncommon, according to NWS Meteorologist Shaun Baines. Baines said that the current wind conditions blowing smoke from the Swan Lake wildfire on the Western Kenai Peninsula have not helped. The mix of air through the different levels of the atmosphere maintain an unstable condition during the day and stabilize by dropping temperatures near the surface at night. These unstable conditions are not allowing the smoke blown from the Kenai Peninsula to escape during the night, aiding in trapping the heat near the surface. Additionally, freezing levels of existing snowpacks at 10,000 feet or higher during these sustained high temperatures will result in greater flow of snowmelt into streams and rivers. Baines said that temperatures may be sustained in the 80’s during the end of the week and even see high temperatures of the upper 80’s on Friday in the Mat-Su Valley.
“It’s just to raise awareness that water levels are going to be high so you should use extra caution,” Baines said.
The Matanuska River has been particularly susceptible to damaging erosion in the past. Baines said that those recreating on or near the rivers should use extreme caution or even avoid river banks due to possible erosion.
Updated with temperature records from NWS Meteorologist Shaun Baines.
The six highest recorded temperatures for the month of June in Palmer mostly occurred during two calendar years. June 28 and 29 in 1997 both reached 82 degrees. The year 1953 had 86 degree temperatures on June 27 and on June 25 and 26 of 1953, the thermometer reached 87 degrees. The highest recorded June temperature in Palmer between 1948 and 2015 was 88 degrees on June 27 of 2011.
The record temperatures in Wasilla nearly all occurred in 1997. In 1991, Wasilla saw temperatures of 76 degrees on June 25. In 1997, June 26-29 all saw temperatures over 80 degrees, with 82 degrees on June 27 and 28 in 1997. The highest recorded June temperature in Wasilla between 1949 and 1999 was 90 degrees on June 15 of 1969.