566
FXUS07 KWBC 311901
PMD30D
PROGNOSTIC DISCUSSION FOR MONTHLY OUTLOOK
NWS CLIMATE PREDICTION CENTER COLLEGE PARK MD
300 PM EDT FRI JUL 31 2026
30-DAY OUTLOOK DISCUSSION FOR AUG 2026
AS OF THE END OF JULY 2026, AN EL NIñO ADVISORY, MEANING THAT EL NIñO
CONDITIONS ARE PRESENT AND EXPECTED TO CONTINUE, REMAINS IN EFFECT. THE LATEST
WEEKLY OBSERVED SEA SURFACE TEMPERATURES (SSTS) IN THE NIñO 3.4 REGION WERE
1.4 DEGREES CELSIUS ABOVE AVERAGE, WHICH IS CONSISTENT WITH THE UPPER END OF A
MODERATE STRENGTH EL NIñO. MEANWHILE, THE MADDEN JULIAN OSCILLATION (MJO) IS
WEAKENING AND IS PREDICTED TO FURTHER WEAKEN IN THE SHORT TERM AS IT MOVES INTO
THE INDIAN OCEAN, AND ENTERS INTO A PERIOD OF DESTRUCTIVE INTERFERENCE WITH EL
NIñO. HOWEVER, RECENT DYNAMICAL MODEL GUIDANCE INDICATES THE POTENTIAL FOR
RE-INTENSIFICATION OF THE MJO SIGNAL IN THE WESTERN PACIFIC (PHASE 6 IN
WHEELER-HENDON SPACE) TOWARD THE MIDDLE OF AUGUST. RECENT TRENDS FOR THE MONTH
OF AUGUST GENERALLY SUPPORT ABOVE NORMAL MID-LEVEL HEIGHTS ACROSS THE WEST,
SOUTHERN PLAINS, AND SOUTHEASTERN ALASKA, WHILE BELOW NORMAL HEIGHTS HAVE BEEN
OBSERVED IN NORTHWESTERN ALASKA. DYNAMICAL MODEL GUIDANCE FROM THE EUROPEAN
CENTRE FOR MEDIUM-RANGE WEATHER FORECASTS (ECMWF) AND THE GLOBAL ENSEMBLE
FORECAST SYSTEM (GEFS) GENERALLY SUPPORT ABOVE NORMAL MID-LEVEL HEIGHTS ACROSS
MOST OF THE LOWER 48 STATES THROUGHOUT MUCH OF THE MONTH OF AUGUST. HOWEVER, A
TROUGH FORECAST OVER SOUTHERN CANADA MAY GRAZE PARTS OF THE NORTHERN PLAINS AND
GREAT LAKES EARLY IN THE MONTH BEFORE SETTLING ACROSS THE NORTHEAST BY THE
MIDDLE OF THE MONTH. CYCLONIC MID-LEVEL FLOW IS GENERALLY FAVORED OVER CENTRAL
MAINLAND ALASKA EARLY IN THE MONTH BEFORE POTENTIALLY RETROGRADING TOWARD THE
WESTERN OR SOUTHWESTERN MAINLAND BY MID-MONTH. THE MAIN CONTRIBUTORS TO THE
UPDATED MONTHLY OUTLOOK FOR AUGUST WERE DYNAMICAL MODEL GUIDANCE, OFFICIAL
NATIONAL WEATHER SERVICE (NWS) SHORT AND EXTENDED RANGE FORECASTS FOR DAYS 1-7,
WEEK-2, AND WEEKS 3-4, THE BACKGROUND EL NIñO STATE, MJO, TRENDS, AND
ANTECEDENT CONDITIONS SUCH AS SOIL MOISTURE AND NEARSHORE SSTS.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE WESTERN AND SOUTHERN TWO-THIRDS
OF THE CONTIGUOUS UNITED STATES (CONUS). CONFIDENCE IS HIGH (GREATER THAN 50
PERCENT CHANCE) FOR ABOVE NORMAL TEMPERATURES ACROSS MUCH OF THE SOUTHERN
PLAINS, WHERE EL NIñO COMPOSITES, TREND, AND DYNAMICAL MODEL GUIDANCE ALL
SUPPORT INCREASED WARMTH. CONFIDENCE IS ALSO HIGH (GREATER THAN 50 PERCENT
CHANCE) FOR ABOVE NORMAL TEMPERATURES ACROSS COASTAL CALIFORNIA DUE TO A
COMBINATION OF PREDICTED MID-LEVEL RIDGING AND OBSERVED ABOVE NORMAL SSTS IN
NEARSHORE WATERS. CONFIDENCE IS LOW ACROSS FROM THE NORTHERN PLAINS AND GREAT
LAKES, WHERE EL NIñO COMPOSITES ARE GENERALLY LESS SUPPORTIVE OF ANOMALOUS
WARMTH. EQUAL CHANCES (EC) OF ABOVE, NEAR, AND BELOW NORMAL TEMPERATURES ARE
INDICATED FOR THESE AREAS. ADDITIONALLY, DYNAMICAL MODEL GUIDANCE PREDICTS A
PROGRESSION OF A MID-LEVEL TROUGH ACROSS SOUTHERN CANADA DURING THE EARLY TO
MIDDLE PARTS OF AUGUST. THIS TROUGH MAY GRAZE THE NORTHERN TIER OF THE CONUS
BEFORE POTENTIALLY SETTLING OVER THE NORTHEAST BY MID-MONTH. DUE TO THE
POTENTIAL FOR ANOMALOUS TROUGHING ACROSS THE NORTHEAST DURING MID TO LATE
AUGUST COUPLED WITH BELOW NORMAL OBSERVED NEARSHORE SSTS, EC IS INDICATED
ACROSS THE NORTHEASTERN CONUS, MARKING A REDUCTION IN ABOVE NORMAL TEMPERATURE
PROBABILITIES RELATIVE TO THE MID-MONTH OUTLOOK. CONFIDENCE IS ALSO LOW ACROSS
ALASKA, DUE TO MIXED SIGNALS AMONG STATISTICAL AND DYNAMICAL MODEL GUIDANCE. AS
SUCH, ELEVATED CHANCES OF ABOVE NORMAL TEMPERATURES ARE LIMITED TO EXTREME
EASTERN SECTIONS OF THE MAINLAND AS WELL AS SOUTHEAST ALASKA. PREDICTED
CYCLONIC MID-LEVEL FLOW AS WELL AS OBSERVED BELOW NORMAL NEARSHORE SSTS
ADJACENT TO THE SOUTH COAST AND ABOVE NORMAL SEA ICE TO THE NORTH OF THE STATE
PRECLUDE FAVORING ABOVE NORMAL TEMPERATURES ACROSS THE REMAINDER OF THE STATE.
ABOVE NORMAL PRECIPITATION IS FAVORED ACROSS A LARGE PORTION OF THE SOUTHWEST
AND GREAT BASIN, AS DYNAMICAL MODEL GUIDANCE IS IN GOOD AGREEMENT ON A RENEWED
PUSH OF MONSOONAL MOISTURE INTO THE REGION FROM SOUTH TO NORTH. CONFIDENCE HAS
INCREASED FOR BELOW NORMAL PRECIPITATION ACROSS THE SOUTHERN PLAINS, AS EL
NIñO COMPOSITES, TREND, AND DYNAMICAL MODEL GUIDANCE ARE ALL CONVERGING ON A
DRIER SOLUTION. CONFIDENCE IS LOW ACROSS MUCH OF THE EASTERN CONUS DUE TO VERY
WEAK SIGNALS AMONG DYNAMICAL MODEL GUIDANCE SUCH AS THE ECMWF ENSEMBLE.
MOREOVER, A SLOW MOVING FRONTAL BOUNDARY EARLY IN AUGUST REDUCES CHANCES OF
BELOW NORMAL PRECIPITATION ACROSS THE SOUTHEASTERN CONUS, RESULTING IN A
REMOVAL OF ENHANCED BELOW NORMAL PROBABILITIES DEPICTED IN THE MID-MONTH
OUTLOOK IN FAVOR OF EC ACROSS THE REGION. A SLIGHT TILT TOWARD ABOVE NORMAL
PRECIPITATION WAS INTRODUCED TO PARTS OF THE NORTHEAST, DUE TO SUPPORT FROM
ECMWF ENSEMBLE PRECIPITATION OUTPUT AND CONSISTENT WITH THE POTENTIAL FOR A
PROLONGED PERIOD OF CYCLONIC MID-LEVEL FLOW MID TO LATE MONTH. A SLIGHT TILT
TOWARD BELOW NORMAL PRECIPITATION IS INDICATED FOR THE COASTAL PACIFIC
NORTHWEST AND SOUTHEAST ALASKA BROADLY CONSISTENT WITH NWS 6-10 DAY AND WEEK-2
OUTLOOKS AS WELL AS RECENT TRENDS. ABOVE NORMAL PRECIPITATION IS FAVORED FOR
MUCH OF WESTERN AND NORTHERN MAINLAND ALASKA DUE TO STRONG TRENDS AS WELL AS
THE POTENTIAL FOR A PROLONGED PERIOD OF MID-LEVEL CYCLONIC FLOW AS DEPICTED BY
DYNAMICAL MODEL GUIDANCE.
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****** PREVIOUS MID-MONTH DISCUSSION BELOW ******
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THE OUTLOOKS FOR AUGUST 2026 ARE ISSUED AGAINST THE BACKDROP OF AN EL NIñO
ADVISORY, MEANING THAT EL NIñO CONDITIONS ARE PRESENT AND EXPECTED TO
CONTINUE. THE LATEST WEEKLY OBSERVED SEA SURFACE TEMPERATURES (SSTS) IN THE
NIñO 3.4 REGION WERE 1.3 DEGREES CELSIUS ABOVE NORMAL, CONSISTENT WITH AN EL
NIñO OF MODERATE STRENGTH. MEANWHILE, THE EASTWARD PROGRESSION OF THE MADDEN
JULIAN OSCILLATION (MJO) IS CURRENTLY STALLED, BUT IS EXPECTED TO RESUME BEFORE
GRADUALLY DISORGANIZING IN LATE JULY. THIS WEAKENING MJO MAY DESTRUCTIVELY
INTERFERE WITH THE BACKGROUND EL NIñO STATE AS IT APPROACHES THE INDIAN OCEAN
NEAR THE BEGINNING OF AUGUST. IN THE EXTRATROPICS, THE ARCTIC OSCILLATION (AO)
HAS BEEN POSITIVE IN EARLY JULY BUT HAS TRENDED TO NEAR ZERO IN RECENT DAYS.
AFTER A BRIEF DIP, THE NORTH ATLANTIC OSCILLATION (NAO) HAS RETURNED TO THE
POSITIVE PHASE, WHILE THE PACIFIC NORTH AMERICAN (PNA) INDEX HAS TRENDED
NEGATIVE. A NEAREST NEIGHBOR ANALYSIS OF THE RECENT EVOLUTION OF THE EL NIñO
SOUTHERN OSCILLATION (ENSO), THE MJO, AND EXTRATROPICAL INDICES ALL PLAYED A
ROLE IN THE AUGUST OUTLOOKS, WITH THE GREATEST WEIGHT PLACED ON ENSO IMPACTS,
DUE TO LARGE UNCERTAINTIES IN THE MJO AND EXTRATROPICAL SIGNALS. ANTECEDENT
CONDITIONS, SUCH AS EXTRATOPICAL SSTS AND SOIL MOISTURE CONDITIONS, WERE ALSO
CONSIDERED WHERE APPROPRIATE AS WERE RECENT TEMPERATURE AND PRECIPITATION
TRENDS. DYNAMICAL GUIDANCE FROM THE COPERNICUS CLIMATE CHANGE SERVICE (C3S),
NORTH AMERICAN MULTI-MODEL ENSEMBLE (NMME), THE COUPLE FORECAST SYSTEM VERSION
2 (CFSV2), AND THE FORECAST CONSOLIDATION TOOL (CON) (WHICH INCLUDES BOTH
DYNAMICAL MODEL INPUT AND STATISTICAL GUIDANCE), ALSO WERE SIGNIFICANT
CONTRIBUTORS TO THE AUGUST OUTLOOKS, AS WAS CONSISTENCY WITH THE MOST RECENT
WEEKS 3-4 OUTLOOKS, WHICH NOW EXTENDS THROUGH THE FIRST WEEK OF AUGUST.
ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE EASTERN AND SOUTH-CENTRAL
CONTIGUOUS UNITED STATES (CONUS), THE WEST COAST, THE NORTHWESTERN CONUS, AND
MOST OF ALASKA. CONFIDENCE IS HIGH (GREATER THAN 50 PERCENT CHANCE) FOR ABOVE
NORMAL TEMPERATURES ACROSS THE SOUTHEAST AND SOUTHERN MID-ATLANTIC, WHERE ABOVE
NORMAL SSTS IN ADJACENT WATERS AS WELL AS DRY SOILS FAVOR WARMER TEMPERATURES.
DYNAMICAL MODELS SUCH AS THE NMME AND C3S ALSO SUPPORT ABOVE NORMAL
TEMPERATURES THERE. ABOVE NORMAL TEMPERATURES ARE ALSO FAVORED (GREATER THAN 40
PERCENT CHANCE) ACROSS THE SOUTHERN PLAINS, CONSISTENT WITH ENSO COMPOSITES AND
TRENDS. A TILT TOWARD WARMER THEN NORMAL CONDITIONS (33 TO 50 PERCENT CHANCE)
EXTENDS NORTHWARD ALONG THE EAST COAST DUE TO SUPPORT FROM NMME AND C3S
GUIDANCE. SIMILARLY, THERE IS A 33 TO 50 PERCENT CHANCE OF ABOVE NORMAL
TEMPERATURES FOR THE NORTHWESTERN CONUS DUE TO STRONG DYNAMICAL MODEL SUPPORT.
HOWEVER, DUE TO LACK OF STATISTICAL GUIDANCE SUPPORT AND BELOW NORMAL SSTS OFF
THE PACIFIC NORTHWEST COAST, ENHANCED ABOVE NORMAL TEMPERATURE PROBABILITIES
WERE KEPT MODEST. A TILT TOWARD ABOVE NORMAL TEMPERATURES (33 TO 40 PERCENT
CHANCE) ALSO EXTENDS SOUTHWARD ALONG THE CALIFORNIA COAST AS SSTS OFF THE
CALIFORNIA COAST LEAN ABOVE NORMAL. BELOW NORMAL TEMPERATURES ARE FAVORED (33
TO 40 PERCENT CHANCE) FOR THE NORTHERN PLAINS DUE TO A STRONG COLD SIGNAL FROM
NATURAL DETRENDED ENSO ANALOGS WITH SUPPORT FROM CONSTRUCTED ANALOGS FROM SOIL
MOISTURE (CAS). HOWEVER, PROBABILITIES WERE KEPT MODEST DUE TO A LACK OF
DYNAMICAL MODEL SUPPORT. EQUAL CHANCES OF ABOVE, BELOW, AND NEAR NORMAL
TEMPERATURES (EC) ARE INDICATED FOR MUCH OF THE INTERIOR SOUTHWESTERN CONUS, AS
COOLER DETRENDED ENSO COMPOSITES AND THE PROSPECTS OF ABOVE NORMAL CLOUDINESS
AND PRECIPITATION CONFLICT WITH WARMER DYNAMICAL MODEL GUIDANCE. ABOVE NORMAL
TEMPERATURES ARE WEAKLY FAVORED FOR MOST OF ALASKA SOUTH OF THE NORTH SLOPE,
CONSISTENT WITH THE NMME. NATURAL ENSO ANALOGS FAVOR WARMTH ACROSS SOUTHWESTERN
MAINLAND ALASKA AND SOUTHEAST ALASKA, HOWEVER, BELOW NORMAL SSTS ALONG MUCH OF
THE SOUTH COAST KEPT ABOVE NORMAL TEMPERATURE PROBABILITIES MUTED. EC IS
INDICATED FOR THE NORTH SLOPE OF ALASKA, AS SEA ICE EXTENT NORTH OF THE STATE
IS CURRENTLY ABOVE NORMAL.
ABOVE NORMAL PRECIPITATION CHANCES ARE ELEVATED ACROSS TWO MAIN AXES ACROSS THE
CONUS. THE FIRST AXIS IS ACROSS MUCH OF THE WEST ASSOCIATED WITH THE POTENTIAL
FOR AN ENHANCED MONSOON. THIS WET SIGNAL HAS SUPPORT FROM THE C3S AND CFSV2 AS
WELL AS FROM ENSO COMPOSITES AND NATURAL ANALOGS (EXCEPT SOUTHERN AREAS).
ADDITIONALLY, THE MOST RECENT WEEKS 3-4 OUTLOOKS TILT WET ACROSS THE SOUTHWEST
AND ADJACENT GREAT BASIN. AS SUCH ABOVE NORMAL PRECIPITATION IS FAVORED (33 TO
50 PERCENT CHANCE) ACROSS MUCH OF THE GREAT BASIN, SOUTHWEST, CENTRAL AND
NORTHERN ROCKIES, AND NORTHERN HIGH PLAINS. THE SECOND AXIS WHERE ABOVE NORMAL
PRECIPITATION IS FAVORED (33 TO 40 PERCENT CHANCE) EXTENDS FROM THE NORTHERN
PLAINS TO THE MIDDLE MISSISSIPPI VALLEY. THESE ELEVATED PROBABILITIES OF ABOVE
NORMAL PRECIPITATION HAVE SUPPORT FROM ENSO COMPOSITES AND MJO NATURAL ANALOGS
AS WELL AS THE CAS TOOL. PROBABILITIES WERE KEPT MODEST DUE TO WEAK SIGNALS
FROM DYNAMICAL MODEL GUIDANCE. BELOW NORMAL PRECIPITATION IS FAVORED (33 TO 50
PERCENT CHANCE) ACROSS PARTS OF THE SOUTHEAST AND SOUTHERN MID-ATLANTIC, DUE TO
SUPPORT FROM DETRENDED ENSO COMPOSITES, MJO NATURAL ANALOGS, AND OBSERVED BELOW
NORMAL SOIL MOISTURE. A SLIGHT TILT (33 TO 40 PERCENT CHANCE) TOWARD BELOW
NORMAL PRECIPITATION IS ALSO INDICATED FOR THE GREAT LAKES REGION, WITH SUPPORT
FROM MJO AND EXTRATROPICAL NATURAL ANALOGS AS WELL AS THE CON. CONFIDENCE IS
LOW ACROSS THE SOUTHERN PLAINS AS ENSO COMPOSITES, TREND, AND TO SOME EXTENT,
DYNAMICAL MODEL GUIDANCE CONFLICTS WITH STRONG WET SIGNALS FROM MJO AND
EXTRATROPICAL NATURAL ANALOGS. DUE TO THIS CONFLICTING GUIDANCE, EC HAS BEEN
ISSUED FOR THIS REGION. A SLIGHT TILT (33 TO 40 PERCENT CHANCE) TOWARD BELOW
NORMAL PRECIPITATION IS INDICATED FOR PARTS OF THE PACIFIC NORTHWEST AND
SOUTHEAST ALASKA, DUE TO SUPPORT FROM TREND, THE NMME, CFSV2, AND THE LATEST
WEEKS 3-4 OUTLOOKS. PROBABILITIES WERE KEPT MUTED IN THESE AREAS DUE TO LACK OF
ENSO SUPPORT. ABOVE NORMAL PRECIPITATION IS FAVORED (33 TO 50 PERCENT CHANCE)
ACROSS MOST OF MAINLAND ALASKA AND THE ALASKA PENINSULA, DUE TO STRONG SUPPORT
FROM TREND AND ENSO. HOWEVER, DUE TO LACK OF DYNAMICAL MODEL SUPPORT,
PROBABILITIES WERE KEPT MODEST.
FORECASTER: SCOTT HANDEL
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 SEP ... WILL BE ISSUED ON THU AUG 20 2026
THESE OUTLOOKS ARE BASED ON DEPARTURES FROM THE 1991-2020 BASE PERIOD.
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