The outlook calls for limited improvement for large areas of the West where recent rain and
snow has reduced long-term precipitation deficits. The depiction for the West reflects the
tradeoffs between the long-term deficits and unfavorable water supply forecasts versus recent
favorable trends, short-term forecasts, and the seasonal precipitation outlook for April-June.
Given the severity of the long-term deficits and the fact that the winter snow season is nearing
its end, only limited improvement for the hydrological drought is anticipated. Nevertheless,
recent or forecast rain and snow will benefit soil moisture for non-irrigated agriculture and
reduce wildfire danger this spring. Since last month, the forecast for western Arizona and
southern California has become less optimistic as we go into the dry season and the odds for
significant precipitation decline. The area of persisting drought has expanded in Utah to
reflect poor water supply prospects due to below-normal winter snows. The constructed analogue
soil moisture (CAS) forecast also implies continuing dryness in this area. The major storm that
brought heavy snows to Wyoming and Colorado on March 17-19 boosted water supply prospects in
both states and throughout the Colorado River Basin. Looking out into spring, the odds for
significant change in the status of the long-term drought decline as the snow season wanes;
hence, the forecast for limited improvement.
Recent trends and historic El Niño composites suggest improving soil moisture trends this spring
in the central Plains and diminishing odds for improvement moving northward into the Dakotas.
The mid-March storm increased soil moisture across the Plains and the Midwest and more relief
is expected later in the month, but the CAS forecasts and precipitation composites based on El
Niño and North Pacific SST patterns imply a tendency for dryness to persist in at least parts
of the region. As a result, drought is forecast to remain in the upper Midwest. Forecast
confidence is low given the time of the year and the recent change in circulation pattern
leading to a wetter near-term outlook.
Heavy late-winter snowpack in Maine will mitigate impacts from long-term drought, but there is
a tendency for drought to persist into spring there as El Niño transitions to neutral
conditions. The result is the forecast for limited improvement.
The odds for dryness diminish in Hawaii as the El Niño fades, but the climatological trend
toward drier weather this time of the year results in a forecast for limited drought