Prognostic Discussion for Monthly Outlook
NWS Climate Prediction Center College Park MD
300 PM EDT Tue Mar 31 2026
30-DAY OUTLOOK DISCUSSION FOR APR 2026
The updated monthly temperature and precipitation outlooks for April 2026 are
based on the latest dynamical model guidance from the GEFS and ECENS, the
latest official WPC temperature and precipitation outlooks for week-1, CPCâs
6-10 day, week-2, and weeks 3-4 500-hPa height and anomaly forecasts, and the
corresponding temperature and precipitation outlooks, the CFSv2 model, CAS
(Constructed Analog on Soil moisture tool), and climatology. Other
considerations included the predicted phase of the Arctic Oscillation (AO),
near-coastal sea-surface temperature (SST) departures, Snow Water Equivalent
(SWE), snow cover departures from normal, soil moisture anomalies, and a
statistical tool that relates March soil moisture to April temperatures. The
MJO signal is incoherent and is considered unlikely to have a significant
impact on the updated April outlook.
The updated April temperature outlook favors above-normal temperatures over
most of the contiguous U.S. (CONUS), with the exception of portions of the
northern tier of states and Upper Mid-Atlantic coast, where Equal Chances (EC)
of above, near, and below-normal temperatures are favored. Probabilities
favoring above-normal temperatures reach 60-70 percent over central and
southern portions of the Great Basin and Rockies, and 50-60 percent over much
of the Southeast including all of Florida. In the West, snowpack is well
below-normal, and in some places confined to just the highest elevations. The
gradual melting of accumulated winter snowpack throughout the spring and summer
months is a critical component of the water budget of the West. The
below-normal snowpack this past winter therefore places additional stress on
alternate water supplies such as reservoirs and groundwater sources. The
largely coast-to-coast anomalous warmth favored over most of the CONUS is
consistent with the CFSv2 model, CAS, and consideration of below-normal soil
moisture in many areas. There is a pronounced negative correlation across much
of the southern half of the CONUS between March soil moisture and April
temperatures, meaning below-normal soil moisture in March is often associated
with above-normal temperatures in April. Above-normal temperatures are also
favored over much of northern and central Alaska, based on the consistency of
favored above-normal temperatures in CPCâs 6-10 day period, 8-14 day period,
and Weeks 3-4. Elsewhere, in areas where the tools conflict, or temperature
signals are weak, EC is favored.
The updated April precipitation outlook favors a broad swath of increased
probabilities for above-normal precipitation from the Southern Plains generally
northeastward across the Middle and Upper Mississippi Valley and adjacent
portions of the eastern Plains, Great Lakes region, Northeast, Ohio Valley, and
Upper Mid-Atlantic region, with maximum probabilities of 60-70 percent over
parts of the Midwestern states. The synoptic weather pattern favored during the
first week of April alone favors anywhere from 2-5 inches of rain throughout
much of this region, which by itself may be enough in some areas to exceed the
local climatology for the entire month. If not, another round of precipitation
is forecast during the second week of April, expected to bring at least
moderate amounts of rainfall to this same broad region. This pattern is
supported by the GEFS and ECENS precipitation forecasts which cover the first
half of April, official WPC and CPC precipitation guidance for Week-1, Week-2,
and Weeks 3-4, and CFSv2. Areas of below-normal precipitation are slightly
favored across most areas west of the Continental Divide (partly supported by
longer-term trends ), the south-central Rockies, and portions of the central
High Plains region, in addition to a significant portion of the southeastern
CONUS. As portions of the Southwest may receive light precipitation at times in
April, it is very difficult to know in advance whether the amounts will exceed
the thresholds for above-normal precipitation in arid and semi-arid areas. Sky
Harbor International Airport in Phoenix, AZ, reports 0.18-inch for its April
(2000-2025) precipitation climatology. Tucson International Airport has a mean
of 0.21-inch for the same period. Only a marginal tilt in the odds for
below-normal precipitation is indicated over the Four Corners region. The areas
of favored relative dryness are generally consistent with CFSv2 and CAS
guidance, though there are some differences in the predicted spatial extent of
below-normal precipitation in both of these regions. Above-normal precipitation
probabilities are also elevated over the western and central Alaska Mainland
largely north of the Alaska Range. This is based in large part on official
precipitation outlooks made for the constituent time scales that compose the
month of April. For all remaining areas, EC is favored.
---------- The earlier 0.5-month lead discussion is shown below â----------
The monthly temperature and precipitation outlooks for April 2026 are based on
extended- and subseasonal-range model guidance, consideration of ENSO phase,
climate drivers (such as sea-surface temperature (SST) and soil moisture
anomalies, and snowpack), recent observations and decadal trends .
The coupled ocean-atmosphere system is in the process of transitioning from a
waning La Nina to ENSO-neutral. Subsurface temperatures in the equatorial
Pacific are now mostly above-average from the surface to a depth of 150-200
meters, with the exception of residual, anomalously cool SSTs over portions of
the east-central Pacific. The weekly Nino 3.4 relative SST anomaly (using the
improved RONI classification) is a nominal -0.5 deg C. As is often the cas e,
atmospheric changes tend to lag oceanic changes. Atmospheric conditions are
still consistent with La Nina, and are expected to play a small role in the
April temperature and precipitation outlooks. Atmospheric outgoing longwave
radiation (OLR) departures are still negative across Indonesia and much of
Australia (corresponding to enhanced tropical rainfall and thunderstorm
activity), and are positive (corresponding to suppressed tropical rainfall and
thunderstorm activity) in the vicinity of the Date Line. A large area of
negative OLR departures is also prominent over and west of the Hawaiian
Islands, consistent with recent Kona Low activity with its heavy rainfall,
gusty winds, and flooding. Low-level wind anomalies are easterly (i.e. enhanced
trades) while upper-level wind anomalies are westerly. CPCs Official ENSO
forecast probability bar graph indicates very high (>80 percent) chances of
ENSO-neutral during the March-April-May (MAM) and April-May-June (AMJ) seasons,
with El Nino predicted (with a 62 percent chance) to be the dominant ENSO phase
by June-July-August (JJA).
The Madden-Julian Oscillation (MJO) signal is largely incoherent, as equatorial
Rossby waves have frequently interrupted the eastward propagation of the
enhanced convective envelope in the Central Pacific during the last few weeks.
There are very significant model differences in the predicted phase and
amplitude of the intraseasonal signal during late March and early April, so the
MJO was not used in the April outlooks. The Arctic Oscillation (AO) is
currently in its positive phase, and GEFS forecasts indicate a gradual
transition to its negative phase in late March, which typically favors
cooler-than-normal temperatures across the Great Lakes and Northeast. Though
support for a negative AO is not overwhelming, anomalously cooler temperatures
were considered for the specified regions noted above in early April.
Near-coastal SSTs are currently below-average in Bristol Bay off southwestern
Mainland Alaska, and just off the coast of the Northeast contiguous U.S.
(CONUS). Above-average SSTs were noted off most of California, and the Gulf
Coast region. Soil moisture data from CPCâs Leaky Bucket model and NASA SPoRT
show widespread below-normal soil moisture encompassing much of the southern
and central Lower 48 states. Areas of near to above-normal soil moisture were
confined largely to the northern tier states. Across a large portion of the
mountainous West, snow water equivalent (SWE) and related snowpack was way
below-normal (< 50 percent). This area stretched from the lower Four Corners
region northwestward to northern California and most of Oregon.
The April temperature outlook favors increased chances of above-normal
temperatures over the southern, central, and interior northwestern CONUS,
covering approximately two-thirds of the Lower 48 states. This is largely
supported by the dynamical and final consolidation forecasts (NMME-Con and
Final-Con, respectively), the CFS, most of the NMME and IMME/C3S, CAS
(Constructed Analog on Soil Moisture tool), and historical trends (OCN tool).
This is consistent with widespread drought and below-normal soil moisture
currently over the CONUS, and with below-normal snowpack over much of the
Interior West. Chances of favored above-normal temperatures exceed 50 percent
over the Florida Peninsula (with April climatologically being the height of the
dry season), and exceed 60 percent over the vicinity of Utah. In Alaska, the
assorted models and tools provide a wide array of solutions, though many showed
northwestern Mainland Alaska to be above-normal. Elsewhere, which includes the
large remainder of Alaska, parts of the Pacific Northwest, north-central CONUS,
Great Lakes, Northeast, and Upper Mid-Atlantic, Equal Chances (EC) of above-,
near-, and below-normal temperatures are favored.
The April precipitation outlook favors elevated chances of above-normal
precipitation over a broad zone that extends from the eastern Plains and most
of the Mississippi Valley and Great Lakes region to the Ohio Valley, western
Tennessee, north-central Appalachians, and Upper Mid-Atlantic region. This
pattern of anomalous wetness is depicted by a number of models (to various
degrees) including the Statistical Consolidation (Stat-Con), NMME-Con, and
Final-Con (the latter being a skill-weighted and calibrated mean of the
Stat-Con and NMME-Con). The uncalibrated NMME, CFS, CanESM5 (one of two
available Canadian models), CAS, uncalibrated IMME/C3S, ECMWF, UKMO (UK Met
Office), DWD (German model) and the two NCAR models (NCAR_CESM1 and NCAR_CCSM4)
also support reasonable variations on this same general theme. Chances for
drier-than-normal conditions are favored across most areas west of the
Continental Divide, with maximum probabilities exceeding 60 percent over the
Central and Southern Great Basin, based on model guidance and precipitation
trends during the last 15 years as shown by the OCN tool. Low snowpack and
significantly warmer temperatures predicted in late March over the West will
accelerate snowmelt. Once much of the snowpack melts, the bare ground will heat
up more quickly, leading to more dryness. Below-normal precipitation is also
favored over Florida and southern Georgia, with April typically being the
height of the Florida dry season and the greatest risk for wildfires. Even
though below-normal precipitation is favored in Florida during April, the
April-May-June (AMJ) seasonal precipitation outlook could verify as
wetter-than-normal, given the transition to the Florida rainy season in late
May or early June. In Alaska, above-normal precipitation is slightly favored
over western portions of the Mainland, based on calibrated and uncalibrated
versions of the C3S, Meteo_France, ECMWF, CFS, UKMO, CMCC (one of two available
Canadian models), and the German model (DWD).
FORECASTER: Anthony Artusa
The climatic normals are based on conditions between 1991 and 2020, following
the World Meteorological Organization convention of using the most recent 3
complete decades as the climate reference period. The probability anomalies
for temperature and precipitation based on these new normals better represent
shorter term climatic anomalies than the forecasts based on older normals.
The next monthly outlook...for May ... will be issued on Thu Apr 16 2026
These outlooks are based on departures from the 1991-2020 base period.
$$