173
FXUS06 KWBC 011902
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT FRI MAY 01 2026
6-10 DAY OUTLOOK FOR MAY 07 - 11 2026
A HIGH LATITUDE BLOCK ASSOCIATED WITH THE NEGATIVE PHASE OF THE NORTH ATLANTIC
OSCILLATION (-NAO) FAVORS TROUGHING RELOADING OVER THE EASTERN CONUS, WITH THE
0Z GEFS AND CANADIAN ENSEMBLES COMING INTO BETTER AGREEMENT REGARDING THE MORE
AMPLIFIED ECMWF ENSEMBLE SOLUTION. THE MANUAL HEIGHT BLEND DEPICTS BELOW-NORMAL
HEIGHTS ACROSS MOST OF THE EASTERN HALF OF THE CONUS EXTENDING TO NEAR THE GULF
COAST, WITH THE LARGEST NEGATIVE ANOMALIES OVER THE NORTHERN GREAT LAKES AND
SOUTHERN ONTARIO. UPSTREAM RIDGING IS FORECAST ACROSS THE NORTHWESTERN CONUS
INTO SOUTHEAST ALASKA, WITH THIS FEATURE SLOWLY MIGRATING FURTHER INTO THE
WESTERN CONUS LATER IN THE PERIOD WHERE POSITIVE HEIGHT ANOMALIES ARE INDICATED
IN THE MANUAL BLEND. SHORTWAVE TROUGHING IS PREDICTED TO UNDERCUT THIS RIDGE
AND PROGRESS ACROSS THE SOUTHWESTERN CONUS AND EVENTUALLY BECOME ABSORBED INTO
THE TROUGH ACROSS THE EAST, RESULTING IN NEAR-NORMAL HEIGHTS EXTENDING INTO THE
LOWER FOUR CORNERS AND PARTS OF THE DESERT SOUTHWEST. TROUGHING IS FORECAST TO
MOVE ACROSS THE WESTERN ALEUTIANS RESULTING IN BELOW-NORMAL HEIGHTS FOR MOST OF
THE ISLANDS, AND NEAR-TO BELOW NORMAL HEIGHTS EXTENDING THROUGH MUCH OF
MAINLAND ALASKA AS THE MID-LEVEL FLOW PATTERN CONTINUES TO WEAKEN. ABOVE-NORMAL
HEIGHTS ARE FAVORED ACROSS SOUTHEAST ALASKA TIED TO RIDGING OVER THE REGION
EARLY IN THE PERIOD. NEAR-NORMAL HEIGHTS ARE FORECAST FOR HAWAII AS TROUGHING
PASSES BY TO THE NORTHEAST OF THE STATE, MAKING A CLOSE APPROACH AROUND THE
OUTSET OF THE PERIOD.
UNSEASONABLY COOL WEATHER IS FORECAST TO CONTINUE OVER MUCH OF THE EASTERN U.S.
DURING EARLY MAY. WHILE A BRIEF MODERATION IS POSSIBLE ACROSS THE EASTERN
SEABOARD EARLY IN THE PERIOD, THE RELOADING TROUGH IS FAVORED TO BRING ANOTHER
ROUND OF BELOW-NORMAL TEMPERATURES THROUGHOUT MUCH OF THE EAST. ADDITIONALLY,
THE ANALOGS DERIVED FROM THE MANUAL HEIGHT BLEND SUPPORT HIGH PROBABILITIES FOR
BELOW-NORMAL TEMPERATURES FOR MUCH OF THE CENTRAL AND EASTERN CONUS, WITH
FURTHER SUPPORT FROM TELECONNECTIONS. GIVEN STRONG TOOL SUPPORT, TODAY'S
FORECAST CONTINUES TO INDICATE ELEVATED CHANCES FOR BELOW-NORMAL TEMPERATURES
FOR MOST AREAS EAST OF THE ROCKIES. SOME AREAS OF THE NORTHERN TIER MAY
CONTINUE TO HAVE OVERNIGHT TEMPERATURES COLD ENOUGH TO SUPPORT LATE SEASON
FROSTS, POTENTIALLY DELAYING ADDITIONAL SPRING BLOOMS OR DAMAGING EXISTING
VEGETATION. ABOVE-NORMAL TEMPERATURE PROBABILITIES ARE INCREASED OVER THE
FLORIDA PENINSULA DUE TO THE INFLUENCE OF SUBTROPICAL RIDGING. RIDGING FAVORS
ELEVATED CHANCES OF ABOVE-NORMAL TEMPERATURES ACROSS THE WESTERN CONUS, WITH
SUPPORT FROM THE REFORECAST AND UNCALIBRATED 0Z GEFS AND ECMWF ENSEMBLES. A
VARIABLE TEMPERATURE PATTERN IS FORECAST ACROSS ALASKA. THE HIGHEST CONFIDENCE
FOR ABOVE-NORMAL TEMPERATURES IS ACROSS SOUTHEAST ALASKA UNDERNEATH INITIAL
RIDGING. TROUGHING NEAR THE ALEUTIANS COMBINED WITH INCREASING EASTERLY SURFACE
FLOW FAVORS NEAR-TO BELOW-NORMAL TEMPERATURES OVER MOST OF THE MAINLAND AND
ALEUTIANS, WITH UNCALIBRATED COOLS COLDER THAN THE REFORECAST GUIDANCE FOR MUCH
OF ALASKA. ABOVE-NORMAL TEMPERATURES ARE LIKELY ACROSS HAWAII.
THE TROUGHING IN THE EAST AND ASSOCIATED FRONTAL BOUNDARY SUPPORTS INCREASED
CHANCES OF UNSETTLED WEATHER ACROSS THE REGION. THE 0Z ECMWF ENSEMBLE CONTINUES
TO INDICATE A POTENT SURFACE LOW DEVELOPING ACROSS THE GREAT LAKES AND
NORTHEAST, WITH A SOUTHWARD EXTENDING FRONTAL BOUNDARY. THE 0Z GEFS AND
CANADIAN DEPICT A WEAKER SURFACE LOW COMPARED TO YESTERDAY, AND PROBABILITIES
FOR ABOVE-NORMAL PRECIPITATION ARE DECREASED RELATIVE TO YESTERDAY, WITH
MODESTLY ENHANCED ODDS (GREATER THAN 40 PERCENT) OVER THE NORTHEAST. SHORTWAVE
TROUGHING MAY LEAD TO INCREASED CHANCES OF ABOVE-NORMAL PRECIPITATION ACROSS
THE SOUTHERN TIER, PARTICULARLY ACROSS THE SOUTHWEST, TIED TO A LOW
CLIMATOLOGY, AND ALONG THE NORTHERN GULF COAST DUE TO THE POTENTIAL FOR
INCREASED CONVECTIVE ACTIVITY. CONVERSELY, RIDGING FAVORS INCREASED CHANCES FOR
BELOW-NORMAL PRECIPITATION ACROSS THE NORTHWESTERN CONUS EXTENDING THROUGH THE
UPPER MIDWEST, LIKELY SHAPED BY SURFACE HIGH PRESSURE ON THE BACKSIDE OF THE
EASTERN TROUGH ALONG WITH WITH STRONG SUPPORT FROM THE ANALOG GUIDANCE. FOR
ALASKA, TOOLS GENERALLY FAVOR ENHANCED ODDS FOR ABOVE-NORMAL PRECIPITATION
ACROSS MUCH OF THE MAINLAND, ALEUTIANS, AND SOUTHEAST ALASKA TIED TO TROUGHING
NEAR THE ALEUTIANS, WHILE NEAR-NORMAL PRECIPITATION IS MOST LIKELY ALONG THE
WESTERN COAST. ABOVE-NORMAL PRECIPITATION IS SLIGHTLY FAVORED ACROSS HAWAII.
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 8, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY
8
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD MODEL AGREEMENT REGARDING A STABLE BLOCKING PATTERN ACROSS THE EAST,
OFFSET BY WEAKENING PRECIPITATION SIGNALS OVER THE WESTERN CONUS, AND A MORE
VARIABLE PATTERN PREDICTED ACROSS ALASKA.
8-14 DAY OUTLOOK FOR MAY 09 - 15 2026
THE 500-HPA PATTERN DURING WEEK-2 IS SIMILAR TO THAT OF THE 6-10 DAY PERIOD.
THE 0Z GEFS, ECMWF, AND CANADIAN ENSEMBLES CONTINUE TO DEPICT ANOMALOUS
TROUGHING ACROSS THE EASTERN U.S., WITH THIS FEATURE GRADUALLY WEAKENING LATER
IN THE PERIOD. THE WEEK-2 MANUAL HEIGHT BLEND INDICATES BELOW-NORMAL HEIGHTS
ACROSS THE MIDWEST AND NORTHEAST, EXTENDING SOUTH TO THE TENNESSEE VALLEY AND
MID-ATLANTIC. THE 0Z ECMWF AND CANADIAN ENSEMBLES DEPICT TROUGHING AND NEGATIVE
HEIGHT ANOMALIES EXTENDING ACROSS MAINLAND ALASKA EARLY IN THE PERIOD. HOWEVER,
THE GEFS IS WEAKER WITH THE TROUGH AND DEPICTS POSITIVE HEIGHT ANOMALIES
BUILDING ACROSS THE STATE BY THE SECOND HALF OF THE PERIOD. GIVEN THE
VARIABILITY AND MODEL UNCERTAINTY, NEAR-NORMAL HEIGHTS ARE INDICATED ACROSS
MOST OF ALASKA FOR THE PERIOD AS A WHOLE. NEAR-NORMAL HEIGHTS ARE ALSO FORECAST
ACROSS HAWAII.
THERE REMAINS GOOD CONFIDENCE FOR A PERSISTENT PERIOD OF UNSEASONABLY COOL
TEMPERATURES ACROSS MUCH OF THE NORTHEASTERN CONUS DURING WEEK-2. THIS
CONTINUES TO BE SUPPORTED BY THE DYNAMICAL MODEL GUIDANCE AS WELL AS A STRONG
SIGNAL FOR BELOW-NORMAL TEMPERATURES IN THE ANALOGS DERIVED FROM THE MANUAL
HEIGHT BLEND. HOWEVER, A WARMING TREND FAVORED LATER IN THE PERIOD WEAKENS ODDS
RELATIVE TO THE 6-10 DAY PERIOD. STRONGER INFLUENCE FROM SUBTROPICAL RIDGING
TILTS MUCH OF THE FLORIDA PENINSULA TOWARD ENHANCED PROBABILITIES FOR
ABOVE-NORMAL TEMPERATURES, WHICH IS SUPPORTED BY THE ECMWF AND GEFS REFORECAST
TOOLS. RIDGING OVER THE WEST SUPPORTS HIGHER PROBABILITIES OF ABOVE-NORMAL
TEMPERATURES ACROSS THE REGION, WITH A LARGER EXTENSION INTO THE GREAT PLAINS
COMPARED TO YESTERDAY. THE WEAKENING MID-LEVEL FLOW PATTERN ACROSS ALASKA LEADS
TO A MORE UNCERTAIN TEMPERATURE FORECAST ACROSS THE STATE. A SLIGHT TILT TOWARD
ENHANCED ABOVE-NORMAL TEMPERATURE PROBABILITIES PERSISTS ACROSS SOUTHEAST
ALASKA. EASTERLY SURFACE FLOW SUPPORTS NEAR- TO BELOW-NORMAL TEMPERATURES OVER
THE REMAINDER OF THE MAINLAND. ABOVE-NORMAL TEMPERATURES ARE LIKELY ACROSS
HAWAII CONSISTENT WITH THE CONSOLIDATION FORECAST TOOL.
TROUGHING OVER THE EAST CONTINUES TO FAVOR ABOVE-NORMAL PRECIPITATION ACROSS
THE REGION. DYNAMICAL MODELS DEPICT MOIST RETURN FLOW PENETRATING FAR WEST INTO
THE DESERT SOUTHWEST, LEADING TO AN ENHANCEMENT OF PROBABILITIES (ABOVE 40
PERCENT) FOR MUCH OF THE REGION, AS WELL AS FOR THE LOWER RIO GRANDE VALLEY.
ANALOG GUIDANCE CONTINUES TO FAVOR ENHANCED CHANCES FOR BELOW-NORMAL
PRECIPITATION ACROSS THE NORTHERN TIER EXTENDING FROM THE PACIFIC NORTHWEST TO
PARTS OF THE UPPER MISSISSIPPI VALLEY. ENHANCED ONSHORE FLOW ALSO FAVORS
SLIGHTLY INCREASED ABOVE-NORMAL PRECIPITATION PROBABILITIES ACROSS SOUTHEASTERN
ALASKA AND MUCH OF THE EASTERN AND CENTRAL MAINLAND. NEAR-NORMAL PRECIPITATION
REMAINS FAVORED OVER THE FAR WESTERN MAINLAND. ABOVE-NORMAL PRECIPITATION
CHANCES ARE INCREASED ACROSS HAWAII.
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 33% OF TODAY'S 0Z GFS
ENSEMBLE MEAN CENTERED ON DAY 11, 34% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN
CENTERED ON DAY 11, AND 33% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 11
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: AVERAGE, 3 OUT OF 5, DUE TO A
FAIRLY PERSISTENT PATTERN FROM THE 6-10 DAY PERIOD AND CONTINUED GOOD TOOL
AGREEMENT, OFFSET BY SOME INCREASING MODEL SPREAD LATER IN THE PERIOD AND A
MORE UNCERTAIN PATTERN ACROSS THE WESTERN CONUS AND ALASKA.
FORECASTER: DANIEL BARANDIARAN
NOTES:
THE NOTATION FOR THE CATEGORICAL FORECAST INDICATED ON THE MAPS IS
THE SAME AS THAT IN THE TABLES: A-ABOVE N-NEAR NORMAL B-BELOW
THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER
(ORANGE, "A"), COLDER (BLUE, "B"), OR CLOSE TO (GRAY, "N") NORMAL.
LABELS ON THE SHADED LINES GIVE THE PROBABILITY (> 33%) OF THE MORE
LIKELY CATEGORY (B OR A). PROBABILITY OF N IS ALWAYS < 40%.
THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING
WETTER (GREEN, "A"), DRIER (TAN, "B"), OR CLOSE TO (GRAY, "N")
NORMAL. LABELS ON THE SHADED LINES GIVE THE PROBABILITY (> 33%) OF
THE MORE LIKELY CATEGORY (B OR A). PROBABILITY OF N IS ALWAYS < 40%.
IN THE SOUTHWEST AND OTHER CLIMATOLOGICALLY DRY REGIONS - THERE WILL
BE A GREATER THAN 33.3% CHANCE OF NO PRECIPITATION AND OCCASIONALLY
EVEN A NORMAL (I.E. MEDIAN) VALUE OF ZERO - ESPECIALLY DURING THE DRY
SEASONS. IN SUCH CASES A FORECAST OF NEAR NORMAL IS EFFECTIVELY A
FORECAST OF LITTLE OR NO PRECIPITATION.
THE CLIMATE PREDICTION CENTER USES 1991-2020 BASE PERIOD MEANS AS
REFERENCE IN THE CLIMATE OUTLOOKS.
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON MAY
21.
ANALOGS TO THE 5 DAY MEAN OBSERVED PATTERN CENTERED 3 DAYS AGO (D-3)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
20060504 - 20190508 - 19980415 - 19980507 - 20150420
ANALOGS TO THE 7 DAY MEAN OBSERVED PATTERN CENTERED 4 DAYS AGO (D-4)
FOR THE REGION FROM 20N TO 70N LATITUDE AND 175E TO 60W LONGITUDE
INCLUDE THE 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19910503 - 19980415 - 19910419 - 20190507 - 19980506
6-10 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 07 - 11 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A B
SRN CALIF A A IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A N
UTAH A N ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA B B S DAKOTA B B
NEBRASKA N N KANSAS N N OKLAHOMA B N
N TEXAS B A S TEXAS B A W TEXAS N A
MINNESOTA B B IOWA B N MISSOURI B N
ARKANSAS B N LOUISIANA B A WISCONSIN B N
ILLINOIS B N MISSISSIPPI B A MICHIGAN B N
INDIANA B N OHIO B A KENTUCKY B A
TENNESSEE B A ALABAMA B A NEW YORK B A
VERMONT B A NEW HAMP B A MAINE B A
MASS B A CONN B A RHODE IS B A
PENN B A NEW JERSEY B A W VIRGINIA B A
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN A A AK N SLOPE B A
AK ALEUTIAN B A AK WESTERN B N AK INT BSN N A
AK S INT B A AK SO COAST N A AK PNHDL A A
8-14 DAY OUTLOOK TABLE
OUTLOOK FOR MAY 09 - 15 2026
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON A B OREGON A B NRN CALIF A N
SRN CALIF A A IDAHO A B NEVADA A N
W MONTANA A B E MONTANA A B WYOMING A N
UTAH A A ARIZONA A A COLORADO A A
NEW MEXICO A A N DAKOTA A B S DAKOTA A B
NEBRASKA A N KANSAS A A OKLAHOMA A A
N TEXAS A A S TEXAS A A W TEXAS A A
MINNESOTA B N IOWA N N MISSOURI N N
ARKANSAS N A LOUISIANA N A WISCONSIN B N
ILLINOIS B N MISSISSIPPI N A MICHIGAN B A
INDIANA B A OHIO B A KENTUCKY B A
TENNESSEE B A ALABAMA N A NEW YORK B A
VERMONT B A NEW HAMP B A MAINE N A
MASS B A CONN B A RHODE IS B A
PENN B A NEW JERSEY B A W VIRGINIA B A
MARYLAND B A DELAWARE B A VIRGINIA B A
N CAROLINA N A S CAROLINA N A GEORGIA N A
FL PNHDL N A FL PENIN A A AK N SLOPE N A
AK ALEUTIAN B N AK WESTERN N N AK INT BSN N A
AK S INT N A AK SO COAST B A AK PNHDL A A
LEGEND
TEMPS WITH RESPECT TO NORMAL PCPN WITH RESPECT TO MEDIAN
A - ABOVE N - NEAR NORMAL A - ABOVE N - NEAR MEDIAN
B - BELOW B - BELOW
THE FORECAST CLASSES REPRESENT AVERAGES FOR EACH STATE. NORMAL
VALUES - WHICH MAY VARY WIDELY ACROSS SOME STATES - ARE
AVAILABLE FROM YOUR LOCAL WEATHER SERVICE FORECAST OFFICE.
FOR ADDITIONAL INFORMATION SEE MESSAGE FXUS06 KWBC - ON AWIPS AS
PMDMRD.
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