PROGNOSTIC DISCUSSION FOR MONTHLY OUTLOOK NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD 830 AM EDT THU JUN 21 2018 30-DAY OUTLOOK DISCUSSION FOR JULY 2018 THE JULY 2018 TEMPERATURE AND PRECIPITATION OUTLOOKS ARE BASED ON DYNAMICAL MODEL GUIDANCE, STATISTICAL TOOLS, CURRENT SOIL MOISTURE CONDITIONS, AND POTENTIAL INFLUENCES FROM MODES OF TROPICAL VARIABILITY. ENSO IS NOT A FACTOR IN THESE OUTLOOKS SINCE IT IS IN A NEUTRAL STATE AND IS PREDICTED TO REMAIN NEUTRAL. THE MADDEN-JULIAN OSCILLATION (MJO) IS NOT LIKELY TO PLAY A SIGNIFICANT ROLE, AS TELECONNECTIONS TO MID-LATITUDE CIRCULATION FEATURES FROM MJO RELATED CONVECTION IS TYPICALLY WEAK DURING JULY. THE PREDICTED EVOLUTION OF THE MJO IS NOT ONE CONDUCIVE TO THE MJO SUPPORTING TROPICAL CYCLONE DEVELOPMENT IN THE EASTERN PACIFIC OR THE ATLANTIC. GIVEN THE PREDICTED STATE OF ENSO AND MJO, HIGHER FREQUENCY MODES THAT ARE NOT PREDICTABLE ON MONTHLY TIME SCALES ARE LIKELY TO INFLUENCE TROPICAL CYCLONE FORMATIONS, AND THE RESULTANT POTENTIAL FOR LARGE MOISTURE INFLUXES INTO THE FORECAST DOMAIN. MODEL OUTLOOKS FROM THE NMME SUITE, MORE RECENT RUNS FROM THE CFS, AND TRENDS FAVOR ABOVE NORMAL TEMPERATURES ACROSS THE WESTERN CONUS, WHERE THE HIGHEST ODDS FOR ABOVE NORMAL TEMPERATURES ARE DEPICTED IN THE OFFICIAL OUTLOOK. OVER PORTIONS OF THE HIGH PLAINS AND GREAT PLAINS, MANY MODELS INDICATE AN AREA WHERE NEAR OR BELOW NORMAL TEMPERATURES ARE FAVORED, WHICH IS IN OPPOSITION TO TRENDS, SO EQUAL CHANCES (EC) IS DEPICTED. CURRENT SOIL MOISTURE CONDITIONS AND DYNAMICAL MODEL OUTPUT ALSO FAVOR ABOVE NORMAL TEMPERATURES OVER THE CENTRAL PLAINS AS WELL AS THE MIDDLE AND LOWER MISSISSIPPI VALLEYS. FURTHER EAST, ESPECIALLY ACROSS THE NORTHEAST, TRENDS ALSO CONTRIBUTE TO THE SIGNAL FOR ABOVE NORMAL TEMPERATURES. ACROSS THE SOUTHEAST, SOME MODELS HAVE LITTLE TO NO SIGNAL FOR TEMPERATURE DEVIATIONS, SO EC IS INDICATED IN THE OFFICIAL OUTLOOK. ACROSS ALASKA, TRENDS FAVOR ABOVE NORMAL TEMPERATURES THOUGH MODEL OUTPUTS SHOW A WEAKNESS ACROSS EASTERN ALASKA. THE OUTLOOK FAVORS ABOVE NORMAL TEMPERATURES OVER WESTERN AND SOUTHERN ALASKA, WHERE MODEL OUTPUT, TRENDS, AND RECENT SST OBSERVATIONS ALIGN. THE PRECIPITATION OUTLOOK IS LESS CERTAIN THAN THE TEMPERATURE OUTLOOK, ESPECIALLY OVER THE GREAT PLAINS. MOST OF THE MODELS FROM THE NMME SUITE AND THE RECENT CFS RUNS DEPICT A STRONG DRY SIGNAL OVER THE CARIBBEAN AND A STRONG WET SIGNAL OVER THE CENTRAL TROPICAL PACIFIC. MOST OF THE MODELS INDICATE A SIGNAL FOR ABOVE NORMAL PRECIPITATION OVER THE SOUTHWEST AND INTO THE CENTRAL ROCKIES, WHICH IS CONSISTENT WITH SOME NORTHWARD MOISTURE TRANSPORT OUT OF THE EAST PACIFIC, AND AN ACTIVE START TO THE SOUTHWEST MONSOON. THE DRY SIGNAL FROM THE CARIBBEAN EXTENDS INTO THE GREAT PLAINS, IMPLYING LESS NORTHWARD MOISTURE TRANSPORT FROM THE LOWER LATITUDES. THIS SIGNAL CONFLICTS WITH TRENDS FOR PORTIONS OF THE LOWER MISSISSIPPI VALLEY, SO PROBABILITIES ARE MUTED COMPARED TO MODEL OUTPUTS. MODEL HINDCASTS REVEAL LITTLE SKILL IN THE CENTRAL AND NORTHERN PLAINS AND TRENDS ARE WEAK IN THOSE AREAS, SO NO SIGNAL FOR EITHER WETTER OR DRIER THAN NORMAL CONDITIONS IS DEPICTED IN THE OUTLOOK. TRENDS IN THE NORTHEAST FOR THE CORE SUMMER MONTHS FAVOR WETTER CONDITIONS, WHILE RECENT CFS OUTPUT SUGGESTS BELOW NORMAL PRECIPITATION FOR THE NORTHEAST, WITH THAT SIGNAL FADING OVER THE MID-ATLANTIC. BOTH TRENDS AND MODEL GUIDANCE FAVOR BELOW NORMAL PRECIPITATION FOR THE PACIFIC NORTHWEST. ABOVE AVERAGE PRECIPITATION IS FAVORED FOR NORTHERN AND WESTERN ALASKA INCLUDING THE ALEUTIANS, SUPPORTED BY MODEL GUIDANCE. ACROSS EASTERN ALASKA, UNCERTAINTY IS GREATER, SO EQUAL CHANCES IS INDICATED. FORECASTER: MATTHEW ROSENCRANS THE CLIMATIC NORMALS ARE BASED ON CONDITIONS BETWEEN 1981 AND 2010, 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 JUL WILL BE ISSUED ON SAT JUNE 30 2018 THESE OUTLOOKS ARE BASED ON DEPARTURES FROM THE 1981-2010 BASE PERIOD. $$