Prognostic Discussion for Monthly Outlook
NWS Climate Prediction Center College Park MD
830 AM EDT Thu May 19 2022


30-DAY OUTLOOK DISCUSSION FOR JUNE 2022

The June 2022 temperature and precipitation outlooks are based on dynamical 
model guidance (including the North American Multi-Model Ensemble (NMME) and 
the week 3-4 model solutions), statistical tools, current soil moisture 
conditions, and La Niña composites. The Madden-Julian Oscillation (MJO) remains 
weak as multiple Kelvin waves (KWs) continue to propagate rapidly eastward over 
the global tropics. The MJO is not expected to provide any significant 
influence on the mid-latitude circulation pattern across North America during 
June. However, the passage of KWs over the Western Hemisphere from late May 
into June and its potential contribution to the development of an early season 
tropical cyclone across the western Caribbean Sea was considered as a factor in 
the precipitation outlook. 

During early to mid-May, anomalous 500-hPa ridging resulted in much above 
normal temperatures throughout the southern Great Plains with positive 
anomalies of more than 6 degrees F across the western half of Texas. Although 
there could be brief periods of weakening of this subtropical riding, ensemble 
means depict the anomalous 500-hPa ridging over the southern tier of the CONUS 
likely persisting through the first half of June. Based on good agreement among 
dynamical and statistical tools, above-normal temperatures are favored across 
the southern two-thirds of the CONUS. The largest probabilities (above 60 
percent) are forecast for western Texas and New Mexico, coinciding with the 
lowest soil moisture. Conversely, anomalously wet soil moisture was one reason 
for equal chances (EC) of below, near, or above-normal temperatures across much 
of the northern Great Plains and upper Mississippi Valley. Also, the calibrated 
NMME supports EC for the northern tier of the CONUS. The EC forecast along much 
of the West Coast was due in part to negative sea surface temperature anomalies 
nearby. The week 3-4 tools, covering the first two weeks of June, along with 
most of the inputs to the NMME support slightly elevated probabilities of below 
normal temperatures across western parts of Oregon and Washington along with 
the Alaska Panhandle. Due to conflicting and weak signals among the tools, EC 
is forecast for the remainder of Alaska. 

The NMME supports elevated probabilities of below-normal precipitation across 
much of the central to southern Great Plains, extending westward to parts of 
the Great Basin, Pacific Northwest, and northern California. The slightly 
larger probabilities, focused from southern Wyoming southward to the Texas 
Panhandle, was due to La Niña composites and week 3-4 tools. Since June is 
typically a dry time of year for southern California and the desert Southwest, 
EC was forecast for these areas. Regardless of any effects from a potential 
early season tropical cyclone, the GEFS and ECMWF models depict broad 
upper-level divergence over the Gulf of Mexico and adjacent areas of the 
northern Gulf Coast and Florida during early to mid-June. This is expected to 
promote enhanced sea breeze convection. Based on this expectation and support 
from the NMME, above-normal precipitation is slightly favored for Florida and 
areas along and close to the northern Gulf Coast. For the remainder of the 
eastern and northern tier of the CONUS and Alaska, a large area of EC was 
necessary in the June precipitation outlook due to weak signals among the 
dynamical model solutions. This large coverage of EC and prospects for an early 
season TC, potentially emerging from the western Caribbean Sea, will be 
reevaluated with the updated June outlook, released on May 31. 

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 Jun will be issued on Tue May 31 2022

These outlooks are based on departures from the 1991-2020 base period.
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