123 FXUS07 KWBC 311905 PMD30D 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, CPCs 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 CPCs 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 ---------- 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 case, 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 CPCs 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. $$