Prognostic Discussion for Monthly Outlook 
NWS Climate Prediction Center College Park MD 
830 AM EDT Thu Apr 16 2026 
 
 
30-DAY OUTLOOK DISCUSSION FOR MAY 2026 
 
The May 2026 Temperature and Precipitation Outlooks are based on the: North 
American Multi-Model Ensemble (NMME) and International Multi-Model Ensemble 
(IMME), consolidation (combination of statistical and dynamical model tools), 
soil moisture influence and its constructed analog, and decadal trends . The 
Madden-Julian Oscillation (MJO) strengthened during early April and dynamical 
models have remained consistent since last week that a robust MJO propagates 
eastward from the West Pacific to the Indian Ocean during the latter half of 
April. This MJO evolution and its potential influence on the mid-latitude 
circulation pattern was considered in the temperature outlook. ENSO-neutral 
conditions are present with El Nino likely to emerge during May-June-July. 
 
The NMME and IMME support an increased chance of above-normal temperatures for 
the western contiguous U.S. (CONUS), much of the Great Plains, and Southeast. 
The largest above-normal temperature probabilities (greater than 50%) are 
forecast for the Pacific Northwest where the calibrated NMME and IMME have the 
strongest warm signal and there is also support from the statistical tools. In 
addition, the larger probabilities are consistent with the expectation for a 
drier-than-normal May. Recent heavy precipitation has moistened topsoil from 
eastern Oklahoma southward into central Texas. The GEFS and ECENS favor a 
continuation of the wet pattern for these areas with an expansion eastward into 
the Lower Mississippi Valley by the end of April. Due to the likelihood that 
topsoil is neutral to wet heading into May and tools favor above-normal 
precipitation for the month, above-normal temperature probabilities from the 
dynamical models are reduced across much of the south-central CONUS. Farther to 
the east, drier topsoil and the consolidation tool lead to an increased chance 
of above-normal temperatures for the Southeast. The current West Pacific MJO 
(phase 7) would favor an amplified 500-hPa trough developing over the eastern 
CONUS by the end of April which may result in a relatively cool start to May 
for the Midwest, Northeast, and Mid-Atlantic. However, if the MJO propagates 
back to the Indian Ocean, then above-normal temperatures could return to these 
areas later in May. Due to this expected variable temperature pattern during 
the month and a weaker warm signal among the dynamical models , equal chances 
(EC) of below, near, or above-normal temperatures are forecast from the Middle 
and Upper Mississippi Valley east to the Mid-Atlantic and Northeast. Elevated 
above-normal temperature probabilities are forecast for eastern Alaska. 
However, the outlook hedged colder across southwestern Alaska with EC forecast 
due to the Week 3-4 GEFS and ECENS favoring near to below normal early in the 
month. Large negative SST anomalies led to the outlook leaning slightly on the 
colder side along coastal southwestern Alaska and the Alaska Peninsula. 
 
Based on the NMME, IMME, and consolidation, below-normal precipitation is 
favored for parts of southeastern Alaska, the Pacific Northwest, and the Great 
Basin. Conversely, these forecast tools support the outlook leaning on the 
wetter side across southwestern Arkansas, southeastern Oklahoma, central to 
eastern Texas, and most of Louisiana. Many of the dynamical models , especially 
the ECMWF, along with trends  favor a wetter May across the Southeast. However, 
equal chances (EC) of below, near, or above-normal precipitation are forecast 
for this region as the wet model signal was offset by a correlation between dry 
April soil moisture and below-normal precipitation during May. As of mid-April, 
soil moisture is below the 5th percentile throughout the Southeast and will 
likely decline further during the next week with summerlike heat and an 
increasing water demand. A large coverage of EC is also forecast across a 
majority of Alaska and the lower 48 states due to high uncertainty at this time 
lead with a monthly precipitation outlook along with low predictability in 
forecasting anomalous convective precipitation throughout the central and 
eastern CONUS. 
 
FORECASTER: Brad Pugh 
 
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. 
 
An updated monthly outlook... for May will be issued on Thu April 30 2026 
 
These outlooks are based on departures from the 1991-2020 base period. 
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