Extended Streamflow Guidance
Issued by NWS
FGUS65 KSTR 041723
NATIONAL WEATHER SERVICE
COLORADO BASIN RIVER FORECAST CENTER
SALT LAKE CITY, UTAH
FEBRUARY 3, 2016
FLOOD POTENTIAL OUTLOOK
The flood potential for Arizona Rivers and streams is above average
at this time.
Because the nature of flooding in Arizona is associated with rainfall
events versus snow melt it`s difficult to determine with much certainty
the flood threat over a season. Existing streamflow, soil, and snowpack
conditions are analyzed for their potential contribution to streamflow
levels during future rainfall events.
Seasonal October-January precipitation was 120 percent of average in
the Salt-Verde River Basin, 110 percent of average for the Gila Basin and
130 percent for the Little Colorado Basin. January precipitation was
105 percent of average in the Salt-Verde River Basin, 70 percent in the
Gila River Basin, and 95 percent of average in the Little Colorado Basin.
January 1st snowpack conditions were 105 percent of median in the
Salt-Verde River Basin, 85 percent of median in the upper Gila,
and 110 percent of median in the Little Colorado River Basin.
Modeled soil moisture states were much below average at the beginning
of the water year. However, Conditions have inproved since December.
February through May runoff volumes are primarily influenced by
the frequency and magnitude of winter rain events.
Due to the improved soil moisture conditions, average snow water
equivalents and the presence of a strong El Nino, the flood potential
for Arizona is above average. Howewver, the latest three month CPC
climate forecast suggesting wetter than average conditions is the
main driving factor for the flood potential.