789
FXUS06 KWBC 251906
PMDMRD
PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT FRI JUL 25 2008
6-10 DAY OUTLOOK VALID FOR JUL 31 - AUG 04, 2008
TODAYS AVAILABLE ENSEMBLE MEAN FORECASTS ARE IN FAIRLY GOOD AGREEMENT ON THE
EXPECTED 500-HPA FLOW PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD,
ALTHOUGH THERE ARE SIGNS THE OVERALL CIRCULATIONS PATTERN MAY START TO UNDERGO
SOME CHANGES. THE PATTERN IS FORECAST TO BE UNUSUALLY AMPLIFIED FOR THIS TIME
OF YEAR WITH TROUGHS PROGGED OVER THE EASTERN HALF OF THE CONUS AND ALASKA/GULF
OF ALASKA. A RIDGE IS EXPECTED OVER THE SOUTHWEST EXTENDING NORTHWARD TO OVER
THE NORTHERN ROCKIES/NORTHERN PLAINS. THE GFS-BASED ENSEMBLE MEAN FORECASTS ARE
A BIT LESS AMPLIFIED AND MORE PROGRESSIVE WITH THE EASTERN TROUGH COMPARED TO
THE ECMWF AND CANADIAN ENSEMBLE MEANS. THE 0Z AND 6Z OPERATIONAL GFS ARE ALSO
MORE PROGRESSIVE WITH THE EASTERN TROUGH AND ARE QUICKER TO RAISE HEIGHTS OVER
THE SOUTHEAST COMPARED TO THE OTHER MODEL SOLUTIONS. THE RECENT OPERATIONAL
ECMWF SOLUTIONS ARE LESS PROGRESSIVE WITH THE EASTERN TROUGH COMPARED TO THE
OTHER MODEL FORECASTS. THE MODELS GENERALLY SHOW FAIR CONTINUITY WITH RESPECT
TO THEIR PREVIOUS SOLUTIONS ALTHOUGH TODAYS GFS-BASED FORECASTS ARE MORE
PROGRESSIVE WITH THE EASTERN TROUGH WHILE THE MOST RECENT ECMWF OPERATIONAL
PROGS ARE LESS PROGRESSIVE WITH THIS FEATURE. TODAYS BLEND CHART INDICATES NEAR
TO BELOW NORMAL HEIGHTS OVER THE EASTERN, SOUTHERN, AND EXTREME NORTHWESTERN
PARTS OF THE CONUS, AND MOST OF ALASKA, WHILE NEAR TO ABOVE NORMAL HEIGHTS ARE
PROGGED OVER THE REMAINDER OF THE CONUS AND THE WESTERN ALEUTIANS. THE TROUGH
OVER THE EASTERN CONUS SHOULD LEAD TO NEAR TO BELOW NORMAL TEMPERATURES OVER
THE SOUTHEAST WHILE THE SOUTHWESTERN RIDGE SHOULD LEAD TO NEAR TO ABOVE NORMAL
TEMPERATURES OVER MUCH OF THE REST OF THE CONUS. THE TROUGH OVER ALASKA SHOULD
CAUSE BELOW NORMAL TEMPERATURES ACROSS THE STATE. THE EASTERN TROUGH SHOULD
PRODUCE ABOVE MEDIAN PRECIPITATION ALONG MOST OF THE EAST COAST AND THE
SOUTHEAST, WHILE SUBSIDENCE ON THE REARSIDE OF THE TROUGH SHOULD LEAD TO BELOW
MEDIAN PRECIPITATION FOR THE GREAT LAKES AND MUCH OF THE OHIO AND CENTRAL AND
SOUTHERN MISSISSIPPI VALLEYS. MESOSCALE CONVECTIVE ACTIVITY SUGGESTS ABOVE
MEDIAN PRECIPITATION OVER PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI
VALLEY WHILE MONSOONAL MOISTURE SHOULD FAVOR ABOVE MEDIAN PRECIPITATION OVER
PARTS OF THE SOUTHWEST, THE CENTRAL AND SOUTHERN ROCKIES AND CENTRAL PLAINS.
ABOVE MEDIAN PRECIPITATION IS FORECAST OVER THE PANHANDLE OF ALASKA AND
SOUTHEASTERN ALASKA DUE TO ANOMALOUS SOUTHWESTERLY FLOW IN ADVANCE OF THE GULF
OF ALASKA TROUGH. MUCH OF THE REST OF ALASKA IS FORECAST TO HAVE NEAR TO BELOW
MEDIAN PRECIPITATION DUE TO ANOMALOUS NORTHERLY FLOW BEHIND THE GULF OF ALASKA
TROUGH.
TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...5 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON DAY
8...5 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...10 PERCENT OF
TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...15 PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN
CENTERED ON DAY 8...10 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON
DAY 8...AND 35 PERCENT OF TODAY'S EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 7.
MODEL(S) OF THE DAY: ECMWF ENSEMBLE MEAN
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE, 4 ON A SCALE OF 1
TO 5, DUE TO GOOD MODEL AGREEMENT AND FAIR AGREEMENT AMONG THE FORECAST TOOLS.
THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN, NEURAL NET AND ANALOG
SPECIFICATIONS FROM THE OFFICIAL BLEND, KLEIN PROBABILITIES FROM VARIOUS
ENSEMBLES, THE CDC REFORECAST TEMPERATURE TOOL, AND THE CPC AUTO BLEND FORECAST.
THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE NORTH AMERICAN ENSEMBLE FORECAST
SYSTEM (NAEFS) PRECIPITATION TOOL, THE CDC REFORECAST PRECIPITATION TOOL,
INSPECTION OF DAILY PRECIPITATION FORECASTS FROM THE VARIOUS MODELS, AND THE
CPC AUTO BLEND PRECIPITATION FORECAST.
8-14 DAY OUTLOOK FOR AUG 02 - 08 2008:
THE GFS SUPERENSEMBLE MEAN AND CANADIAN ENSEMBLE MEAN INDICATE VERY LITTLE
CHANGE TO THE OVERALL CIRCULATION PATTERN DURING WEEK 2 COMPARED TO THEIR
FORECASTS FOR THE 6-10 DAY PERIOD. THERE ARE SOME SIGNS THAT THE MAJOR
CIRCULATION FEATURES MAY UNDERGO A SLIGHT RETROGRESSION BETWEEN THE 6-10 DAY
AND WEEK 2 PERIODS. AS WAS TRUE FOR THE 6-10 DAY PERIOD THE 0Z AND 6Z
OPERATIONAL GFS ARE MORE PROGRESSIVE WITH THE EASTERN TROUGH AND ARE QUIKCER TO
RAISE HEIGHTS OVER THE SOUTHEAST COMPARED TO THE ENSEMBLE MEAN SOLUTIONS. THE
ENSEMBLE MEAN FORECASTS SHOW GOOD CONTINUITY WITH RESPECT TO THEIR SOLUTIONS
FROM YESTERDAY ALTHOUGH THE MOST RECENT GFS-BASED SOLUTIONS ARE MORE
PROGRESSIVE WITH THE EASTERN TROUGH. TODAYS BLEND CHART INDICATES NEAR TO BELOW
NORMAL HEIGHTS OVER THE SOUTHEAST AND ALONG THE SOUTHERN TIER OF THE CONUS, AND
NEAR TO ABOVE NORMAL HEIGHTS OVER THE REMAINDER OF THE COUNTRY. HEIGHTS OVER
ALASKA ARE FORECAST TO BE BELOW NORMAL EXCEPT FOR THE PANHANDLE, THE
SOUTHWESTERN PART OF THE STATE, AND THE ALEUTIANS, WHERE NEAR TO ABOVE NORMAL
HEIGHTS ARE PROGGED. THE TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR
WEEK 2 ARE LITTLE CHANGED FROM THOSE DEPICTED FOR THE 6-10 DAY PERIOD. HOWEVER,
THE AREA OF BELOW NORMAL TEMPERATURES FORECAST OVER THE SOUTHEAST SHRINKS IN
AREAL SIZE DURING WEEK 2 COMPARED TO THE 6-10 DAY PERIOD, AND THE NORTHEAST IS
FORECAST TO TREND TOWARDS A DRIER PATTERN DURING WEEK 2.
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL
0Z GFS CENTERED ON DAY 11...5 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON
DAY 11...10 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...15
PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...15 PERCENT OF
TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 50 PERCENT OF TODAY'S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOUT AVERAGE, 3 ON A SCALE OF 1
TO 5 DUE TO FAIR AGREEMENT AMONG THE MODELS AND FAIR AGREEMENT AMONG THE
FORECAST TOOLS.
THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN, NEURAL NET AND ANALOG
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE CDC REFORECAST TEMPERATURE TOOL,
THE KLEIN PROBABILITIES FROM THE GFS AND CANADIAN ENSEMBLES, AND THE CPC AUTO
BLEND FORECAST.
THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE NORTH AMERICAN ENSEMBLE FORECAST
SYSTEM (NAEFS) PRECIPITATION FORECAST, THE CDC REFORECAST PRECIPITATION TOOL,
THE NEURAL NET PROBABILITIES FROM THE GFS AND CANADIAN ENSEMBLES, CALIBRATED
PRECIPITATION FROM THE GFS MODEL RUNS, AND THE CPC AUTO BLEND FORECAST.
FORECASTER: R. SCHECHTER
NOTES:
OPERATIONAL CHANGE: AS OF JULY 5 2005 SHADED MAPS HAVE REPLACED THE
CONTOUR-ONLY MAPS ON THE CPC WEB SITE. THE CONTOURED MAPS ARE
STILL AVAILABLE AT THEIR CURRENT FILE NAMES - SO DIRECT-LINKED USERS
ARE NOT AFFECTED. AWIPS GRAPHICS ARE ALSO NOT AFFECTED BY THIS
CHANGE.
AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OTHERWISE -
FORECASTS INCORPORATE FORECASTER INPUT.
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
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 NARRATIVE DESCRIPTION OF THE FORECAST PATTERNS FOR TEMPERATURE
AND PRECIPITATION FOR BOTH THE 6-10 OR 8-14 DAY PERIODS HAS BEEN
DISCONTINUED. THE STATE TABLES FOR BOTH THE 6-10 AND 8-14 DAY
PERIODS ARE NOW CONTAINED IN THIS MESSAGE...AVAILABLE AS PMDMRD ON
AWIPS.
THE CLIMATE PREDICTION CENTER USES 1971-2000 BASE PERIOD MEANS FOR
TEMPERATURE...PRECIPITATION...AND 500-HPA HEIGHTS AS REFERENCE IN
THE CLIMATE OUTLOOKS.
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON
AUGUST 21.
NEW NOTE EFFECTIVE MAR 16 2004:
THE GLOSSARY FORMERLY FOUND AT THIS LOCATION WILL NO LONGER BE
TRANSMITTED AS PART OF THIS MESSAGE. IF YOU WISH TO SEE THE
DEFINITIONS OF TERMS USED IN THESE MESSAGES... PLEASE GO TO THE
CPC WEB PAGE AT (USE LOWER CASE) HTTP://WWW.CPC.NCEP.NOAA.GOV
AND FOLLOW THE APPROPRIATE LINKS.
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:
19640705 - 19800730 - 19910729 - 19690728 - 19700808
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 5 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19800731 - 19640705 - 19910731 - 19690728 - 19950806
6 TO 10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 31 - AUG 04, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N N OREGON N B NRN CALIF A B
SRN CALIF A B IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A B
UTAH A B ARIZONA A N COLORADO A N
NEW MEXICO N A N DAKOTA A A S DAKOTA A N
NEBRASKA A N KANSAS A B OKLAHOMA A B
N TEXAS A B S TEXAS N N W TEXAS N N
MINNESOTA A A IOWA A N MISSOURI A B
ARKANSAS A B LOUISIANA N N WISCONSIN A N
ILLINOIS A B MISSISSIPPI B N MICHIGAN A B
INDIANA N B OHIO N B KENTUCKY N B
TENNESSEE N N ALABAMA B A NEW YORK A N
VERMONT A N NEW HAMP A A MAINE A A
MASS N A CONN N A RHODE IS N A
PENN N N NEW JERSEY N A W VIRGINIA N N
MARYLAND N A DELAWARE N A VIRGINIA B N
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N N AK N SLOPE B N
AK ALEUTIAN B N AK WESTERN B B AK INT BSN B N
AK S INT B N AK SO COAST B A AK PNHDL B A
8 TO 14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 02 - 08, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N B OREGON N B NRN CALIF N B
SRN CALIF A N IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A N
UTAH A B ARIZONA A N COLORADO N N
NEW MEXICO N A N DAKOTA N A S DAKOTA N N
NEBRASKA N N KANSAS N B OKLAHOMA A B
N TEXAS A B S TEXAS A N W TEXAS A B
MINNESOTA N A IOWA N N MISSOURI N N
ARKANSAS N B LOUISIANA N N WISCONSIN A A
ILLINOIS A N MISSISSIPPI N N MICHIGAN A N
INDIANA A N OHIO A B KENTUCKY N N
TENNESSEE N N ALABAMA B A NEW YORK A B
VERMONT A B NEW HAMP A B MAINE A N
MASS A N CONN A N RHODE IS N N
PENN A B NEW JERSEY N N W VIRGINIA A B
MARYLAND N N DELAWARE N N VIRGINIA N N
N CAROLINA N A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N N AK N SLOPE B N
AK ALEUTIAN N N AK WESTERN B N AK INT BSN B A
AK S INT B A AK SO COAST B A AK PNHDL B N
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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