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FXUS06 KWBC 211936
PMDMRD
PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT THU AUG 21 2008
6-10 DAY OUTLOOK VALID FOR AUG 27 - 31 2008
TODAYS AVAILABLE ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE
EXPECTED 500-HPA FLOW PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD.
TROUGHS ARE FORECAST OVER NORTHWESTERN ALASKA, THE PACIFIC NORTHWEST AND THE
NORTHWESTERN ATLANTIC, ALTHOUGH THE ECMWF ENSEMBLE MEAN IS FURTHER EAST WITH
THE LATTER FEATURE. A WEAK TROUGH, ASSOCIATED WITH THE REMAINS OF TROPICAL
STORM FAY, IS FORECAST TO BE OVER THE SOUTHERN PLAINS/LOWER MISSISSIPPI VALLEY.
A WEAK SUBTROPICAL RIDGE IS FORECAST ACROSS THE REMAINDER OF THE SOUTHERN
CONUS. A RIDGE IS PROGGED TO DEVELOP NORTH OF THE GREAT LAKES. THE LARGEST
MODEL UNCERTAINTY CONTINUES TO BE THE HANDLING OF THE REMAINS OF TROPICAL STORM
FAY. THE INTERACTION OF THIS SYSTEM WITH A MID-LATITUDE TROUGH VARIES BETWEEN
MODELS AND EVEN BETWEEN SUBSEQUENT RUNS OF THE SAME MODEL. TODAYS OPERATIONAL
MODEL SOLUTIONS ARE IN BASICALLY GOOD AGREEMENT WITH THE ENSEMBLE MEAN PROGS
FOR THE MAIN CIRCULATION FEATURES ALTHOUGH THERE ARE DIFFERENCES WITH REGARD TO
THE HANDLING OF THE REMAINS OF TROPICAL STORM FAY AND WITH THE EVOLUTION OF
TROUGH ENERGY MOVING ACROSS THE EASTERN PACIFIC TO THE NORTHWEST CONUS. THE
MODELS GENERALLY SHOW GOOD CONTINUITY WITH RESPECT TO THEIR PREVIOUS SOLUTIONS
ALTHOUGH THE OPERATIONAL RUNS DO INDICATE SOME VARIABILITY IN REGARD TO THE
EVOLUTION OF THE TROUGH OVER THE EAST/CENTRAL CONUS AS IT INTERACTS WITH THE
REMAINS OF TROPICAL STORM FAY. TODAYS BLEND CHART INDICATES NEAR TO BELOW
NORMAL 500-HPA HEIGHTS OVER ALASKA AND ALL OF THE CONUS, EXCEPT FOR THE EASTERN
PART OF THE NORTHERN PLAINS, THE GREAT LAKES, THE NORTHERN MIDDLE ATLANTIC AND
THE NORTHEAST WHERE NEAR TO ABOVE NORMAL HEIGHTS ARE PROGGED. THE AREA OF BELOW
NORMAL HEIGHTS OVER THE SOUTHEAST SHOULD LEAD TO BELOW NORMAL TEMPERATURES FOR
MUCH OF THE SOUTHEAST, TENNESSEE VALLEY, LOWER MISSISSIPPI VALLEY AND EASTERN
SECTIONS OF THE SOUTHERN PLAINS, WHILE ABOVE NORMAL HEIGHTS OVER THE NORTHEAST,
GREAT LAKES UPPER MISSISSIPPI VALLEY AND EASTERN NORTHERN PLAINS LEADS TO
ABOVE NORMAL TEMPERATURES FOR THOSE REGIONS. THE RIDGE OVER THE SOUTHWEST
SHOULD LEAD TO ABOVE NORMAL TEMPEATURES FOR SOUTHERN CALIFRONIA, WHILE THE
TROUGHS OVER ALASKA AND THE PACIFIC NORTHWEST SUGGESTS BELOW NORMAL
TEMPERATURES FOR THOSE AREAS. ABOVE MEDIAN PRECIPITATION IS EXPECTED FOR THE
SOUTHEAST AND ALONG THE GULF COAST AS THE REMAINS OF TROPICAL STORM FAY
INTERACTS WITH A WEAK TROUGH OVER THE EAST/CENTRAL CONUS. THE RIDGE OVER THE
SOUTHWEST SHOULD CAUSE BELOW MEDIAN PRECIPITATION OVER MUCH OF THAT REGION.
ONSHORE FLOW SHOULD LEAD TO ABOVE MEDIAN PRECIPITATION FOR THE ALASKAN
PANHANDLE AND NORTHWESTERN WASHINGTON STATE. THE PACIFIC NORTHWEST TROUGH LEADS
TO ABOVE MEDIAN PRECIPITATION FOR PARTS OF THE NORTHERN AND CENTRAL ROCKIES AND
NORTHERN PLAINS. ANOMALOUS NORTHERLY FLOW LEADS TO BELOW MEDIAN PRECIPITATION
FOR NORTHWESTERN ALASKA AND THE ALEUTIANS.
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...20 PERCENT OF
TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S 6Z GFS
ENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S CANADIAN ENSEMBLE MEAN
CENTERED ON DAY 8...AND 25 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 ABOUT AVERAGE, 3 ON A SCALE OF 1
TO 5, DUE TO FAIR MODEL AGREEMENT AND FAIRLY GOOD AGREEMENT AMONG THE TOOLS,
OFFSET BY UNCERTAINITIES ASSOCIATED WITH THE INTERACTION OF THE REMAINS OF
TROPICAL STORM FAY AND A MID-LATITUDE TROUGH.
THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN, NEURAL NET, AND ANALOG
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE AUTO TEMPERATURE FORECAST, THE
NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE PROBABILITY
FORECASTS, THE KLEIN PROBABILITIES FROM THE VARIOUS ENSEMBLES, AND UNCALIBRATED
AND CALIBRATED TEMPERATURES FROM THE GFS ENSEMBLE MEAN.
THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG AND NEURAL NET
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE AUTO PRECIPITATION FORECAST, THE
NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) PRECIPITATION PROBABILITY
FORECASTS, NEURAL NET PROBABILITIES FROM THE VARIOUS ENSEMBLES, AND INSPECTION
OF THE DAILY PRECIPITATION FORECASTS FROM THE VARIOUS MODEL RUNS.
8-14 DAY OUTLOOK FOR AUG 29 - SEP 04, 2008:
FOR WEEK 2 THE GFS AND CANADIAN ENSEMBLE MEANS DEPICT A FLOW PATTERN WHICH IS
VERY SIMILAR TO, THOUGH GENERALLY A LITTLE LESS AMPLIFIED THAN, THAT FORECAST
FOR THE 6-10 DAY PERIOD. THE 0Z AND 6Z OPERATONAL GFS ARE IN FAIRLY GOOD
AGREEMENT WITH THE ENSEMBLE MEAN SOLUTIONS ALTHOUGH THE 6Z OPERATIONAL GFS IS
MORE PROGRESSIVE WITH JET ENERGY MOVING ACROSS THE NORTHERN PLAINS/UPPER
MISSISSIPPI VALLEY. THE ENSEMBLE MEAN SOLUTIONS SHOW GOOD CONTINUITY WITH
RESPECT TO THEIR PREVIOUS FORECASTS. TODAYS BLEND CHART SHOWS NEAR TO ABOVE
NORMAL HEIGHTS OVER THE NORTHERN AND CENTRAL PLAINS, THE UPPER AND MIDDLE
MISSISSIPPI VALLEY, THE GREAT LAKES, THE NORTHEAST AND PARTS OF THE MIDDLE
ATLANTIC. ELSEWHERE OVER THE CONUS AND ALASKA, NEAR TO BELOW NORMAL HEIGHTS ARE
PROGGED. THE EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK 2
ARE LITTLE CHANGED FROM THOSE FORECAST FOR THE 6-10 DAY PERIOD, ALTHOUGH THE
CENTRAL GREAT BASIN IS EXPECTED TO TRANSITION TO A DRIER WEATHER 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...15 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...20
PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...30 PERCENT OF
TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 25 PERCENT OF TODAY'S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS BELOW AVERAGE, 2 ON A SCALE OF 1
TO 5 DUE TO FAIR AGREEMENT AMONG THE MODELS OFFSET BY RELATIVELY POOR AGREEMENT
AMONG THE FORECAST TOOLS.
THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN, ANALOG AND NEURAL NET
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE AUTO TEMPERATURE FORECAST, THE
NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE PROBABILITY
FORECASTS, AND THE KLEIN PROBABLILITIES FROM THE GFS AND CANADIAN ENSEMBLES.
THE 8-14 DAY PRECIPITATION PROG IS BASED ON THE THE NORTH AMERICAN ENSEMBLE
FORECAST SYSTEM (NAEFS) PRECIPITATION PROBABILITY FORECASTS, THE AUTO BLEND
PRECIPITATION FORECAST, NERUAL NET PROBABILITIES FROM THE GFS AND CANADIAN
ENSEMBLES, AND CALIBRATED PRECIPITATION PERCENTAGES FROM THE GFS SUPERENSEMBLE.
FORECASTER: 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:
19670902 - 19710830 - 19990828 - 19850803 - 19760825
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:
19670902 - 19710829 - 19850802 - 19990827 - 19500903
6 TO 10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 27 - 31, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B N NRN CALIF A B
SRN CALIF A B IDAHO B A NEVADA B B
W MONTANA B A E MONTANA N A WYOMING B A
UTAH B A ARIZONA N B COLORADO B N
NEW MEXICO B B N DAKOTA A A S DAKOTA A A
NEBRASKA N N KANSAS N B OKLAHOMA N B
N TEXAS B A S TEXAS B N W TEXAS N B
MINNESOTA A A IOWA A N MISSOURI N N
ARKANSAS B A LOUISIANA B A WISCONSIN A B
ILLINOIS A N MISSISSIPPI B A MICHIGAN A B
INDIANA A N OHIO A N KENTUCKY N A
TENNESSEE B A ALABAMA B A NEW YORK A N
VERMONT A B NEW HAMP A N MAINE A B
MASS A N CONN A N RHODE IS A A
PENN A N NEW JERSEY A A W VIRGINIA N A
MARYLAND N A DELAWARE N A VIRGINIA B A
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N A AK N SLOPE N N
AK ALEUTIAN B B AK WESTERN B B AK INT BSN N A
AK S INT B A AK SO COAST B A AK PNHDL B A
8 TO 14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 29 - SEP 04, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B A OREGON B N NRN CALIF A B
SRN CALIF A B IDAHO B N NEVADA N B
W MONTANA B A E MONTANA N A WYOMING N B
UTAH B B ARIZONA N B COLORADO N B
NEW MEXICO N B N DAKOTA A A S DAKOTA A A
NEBRASKA A N KANSAS N N OKLAHOMA N N
N TEXAS B B S TEXAS N A W TEXAS N B
MINNESOTA A A IOWA A N MISSOURI A B
ARKANSAS N A LOUISIANA B A WISCONSIN A N
ILLINOIS A B MISSISSIPPI B A MICHIGAN A B
INDIANA A B OHIO A N KENTUCKY A A
TENNESSEE N A ALABAMA B A NEW YORK A N
VERMONT A N NEW HAMP A N MAINE A B
MASS N A CONN A A RHODE IS N A
PENN A N NEW JERSEY A A W VIRGINIA A A
MARYLAND N A DELAWARE N A VIRGINIA N A
N CAROLINA N A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN B N AK N SLOPE N N
AK ALEUTIAN B N AK WESTERN B A AK INT BSN N A
AK S INT B A AK SO COAST B A AK PNHDL B 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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