Extended Streamflow Guidance
Issued by NWS
FGUS65 KSTR 051958
NATIONAL WEATHER SERVICE
COLORADO BASIN RIVER FORECAST CENTER
SALT LAKE CITY, UTAH
MARCH 5, 2014
FLOOD POTENTIAL OUTLOOK
The flood potential for Arizona Rivers and streams is low at this
time. It is low because of the decrease in overall snowpack and due
to the low probability of a significant rain event this month.
Because the nature of flooding in Arizona is associated with rainfall
events versus snow melt it`s difficult to ascertain 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-February precipitation was 50 percent of average in
the Salt-Verde River Basin, 35 percent of average for the Gila Basin and
60 percent for the Little Colorado Basin. February precipitation was
15 percent of average in the Salt-Verde River Basin, 15 percent in the
Gila River Basin, and 20 percent of average in the Little Colorado Basin.
March 1st snowpack conditions were near 5 percent of average in the
Salt-Verde River Basin, 5 percent of average in the upper Gila,
and 5 percent of average in the Little Colorado River Basin.
Modeled soil moisture states remain below average in the Gila, Salt-Verde
and Little Colorado Basins.
Based on these existing conditions, the Gila, Salt-Verde and Little
Colorado are likely to have a low to moderate response due to any heavy
rainfall received this month.
Given the presence of ENSO Neutral climate conditions, there is an
equal chance for above and below average rainfall into the spring months.
The latest CPC climate forecasts suggest drier than average precipitation
conditions for March. If these forecasts verify, there could be a reduction
in runoff response due to snowmelt runoff and rainfall.