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FXUS06 KWBC 301954
PMDMRD
PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT WED JUL 30 2008
6-10 DAY OUTLOOK VALID FOR AUG 05 - 09 2008
TODAYS EUROPEAN AND CANADIAN ENSEMBLE MEAN HEIGHT FORECASTS HAVE COME INTO
BETTER AGREEMENT WITH THE GFS-BASED ENSEMBLES, THOUGH THEY STILL ARE SLIGHTLY
LESS AMPLIFIED OVER THE CONUS. IN ADDITION, THE GFS-BASED ENSEMBLES PREDICT A
500-HPA HEIGHT MAXIMUM IN THE SUBTROPICAL RIDGE NEAR THE FOUR CORNERS AREA,
WHEREAS THE EUROPEAN AND CANADIAN ENSEMBLE MEANS PREDICT THIS MAXIMUM HEIGHT
VALUE 10 TO 15 DEGREES LONGITUDE FURTHER EAST. MOST NUMERICAL RUNS SHOW THE
EASTERN TROUGH OFF THE COAST, WITH THE MEAN AXIS NEAR 70 W. THE EUROPEAN AND
CANADIAN ENSEMBLES ALSO DIFFER FROM THE GFS ENSEMBLES IN THAT THEY PREDICT THE
LARGE ARCTIC VORTEX NEAR THE POLE TO BE CLOSER TO ALASKA, AND THEREFORE PLAYING
A LARGER ROLE IN AFFECTING THE WEATHER ACROSS THE NORTH SLOPE AND BROOKS RANGE.
IN FACT, MOST OF ALASKA IS FORECAST TO BE UNDER THE INFLUENCE OF THIS BROAD
TROUGH, WHICH EXTENDS SOUTHWARD ACROSS MUCH OF THE GULF OF ALASKA, MOST
CLEARLY INDICATED BY THE VARIOUS DETERMINISTIC RUNS.
TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z
GFS CENTERED ON DAY 8...10 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON
DAY 8...10 PERCENT OF TODAY'S OPERATIONAL ECMWF CENTERED ON DAY 7...20 PERCENT
OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 8...20 PERCENT OF TODAY'S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 30 PERCENT OF TODAY'S EUROPEAN
ENSEMBLE MEAN CENTERED ON DAY 7.
MODEL(S) OF THE DAY: EUROPEAN ENSEMBLE MEAN
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD IS ABOVE AVERAGE, 4 ON A SCALE OF 1
TO 5, BECAUSE OF BETTER AGREEMENT BETWEEN THE 3 SETS OF ENSEMBLES (GFS,
EUROPEAN AND CANADIAN).
THE 6-10 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS
FROM THE OFFICIAL BLEND, THE CDC REFORECAST TEMPERATURE TOOL, AND THE NORTH
AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE TOOL. RECENTLY OBSERVED
TEMPERATURES ACROSS THE CONUS WERE ALSO CONSIDERED, AS WELL AS COASTAL OCEAN
SURFACE TEMPERATURES.
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, AND THE CDC REFORECAST PRECIPITATION TOOL.
IT IS ALSO BASED ON 12Z GFS MODEL PRECIPITATION AND IMPLIED STORM TRACKS.
RECENTLY OBSERVED RAINFALL PATTERNS ACROSS THE CONUS WERE ALSO CONSIDERED.
8-14 DAY OUTLOOK FOR AUG 07 - 13 2008:
THE GFS ENSEMBLE RUNS CONTINUE TO FORECAST A TROUGH-RIDGE-TROUGH PATTERN ACROSS
THE CONUS DURING THE WEEK 2 PERIOD, THOUGH THE EAST COAST TROUGH IS PREDICTED
TO RETROGRADE SLIGHTLY FROM ITS EXPECTED 6-10 DAY POSITION. THIS PLACES THE
TROUGH AXIS VERY CLOSE TO THE ATLANTIC COAST. THE LARGE ARCTIC VORTEX PROGGED
OVER THE ARCTIC OCEAN DURING THE 6-10 DAY FORECAST PERIOD IS EXPECTED TO MOVE
FURTHER AWAY FROM ALASKA WITH TIME. THE CANADIAN ENSEMBLE MEAN PREDICTS THE
EAST COAST TROUGH OFF THE ATLANTIC COAST NEAR 70W AND IS VERY CONSISTENT WITH
ITS 6-10 DAY MEAN POSITION. THE OPERATIONAL 0Z GFS IS SIGNIFICANTLY DIFFERENT
FROM THE OTHER MODEL SOLUTIONS IN THAT IT PREDICTS A BROAD TROUGH OVER THE
NORTHEASTERN CONUS, AND ALSO ANTICIPATES A VERY INTENSE CYCLONIC CIRCULATION
ALOFT OVER THE GULF OF ALASKA. THIS SAME CIRCULATION FEATURE IS PREDICTED BY
THE OPERATIONAL 6Z GFS TO BE MUCH WEAKER AND SHIFTED EASTWARD TO NEAR THE
ALASKA PANHANDLE.
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 20 PERCENT OF TODAY'S OPERATIONAL
6Z GFS CENTERED ON DAY 11...20 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...20
PERCENT OF TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...AND 20 PERCENT
OF TODAY'S CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS NEAR AVERAGE, 3 ON A SCALE OF 1
TO 5.
THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND ANALOG SPECIFICATIONS
FROM THE OFFICIAL BLEND, THE CDC REFORECAST TEMPERATURE TOOL, AND THE NORTH
AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE TOOL.
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, AND THE CDC REFORECAST PRECIPITATION
TOOL. IT IS ALSO BASED ON 12Z GFS MODEL PRECIPITATION AND IMPLIED STORM TRACKS.
FORECASTER: ARTUSA
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:
19580806 - 19690813 - 19800731 - 19910803 - 19700809
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 - 19700809 - 19910801 - 19690812 - 19580806
6 TO 10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 05 - 09, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B N OREGON B B NRN CALIF B B
SRN CALIF N N IDAHO B B NEVADA N B
W MONTANA B N E MONTANA B A WYOMING N A
UTAH N B ARIZONA N N COLORADO A A
NEW MEXICO A N N DAKOTA N A S DAKOTA N A
NEBRASKA A A KANSAS A A OKLAHOMA A B
N TEXAS A B S TEXAS N B W TEXAS A N
MINNESOTA N A IOWA A A MISSOURI A N
ARKANSAS A B LOUISIANA A N WISCONSIN N N
ILLINOIS A A MISSISSIPPI A B MICHIGAN N N
INDIANA A N OHIO A N KENTUCKY A N
TENNESSEE A B ALABAMA A B NEW YORK N N
VERMONT B A NEW HAMP B A MAINE B A
MASS B A CONN N A RHODE IS N A
PENN A N NEW JERSEY N N W VIRGINIA A N
MARYLAND A N DELAWARE A N VIRGINIA A N
N CAROLINA A N S CAROLINA N N GEORGIA N N
FL PNHDL N N FL PENIN B N AK N SLOPE N N
AK ALEUTIAN N B AK WESTERN A B AK INT BSN A B
AK S INT A B AK SO COAST N B AK PNHDL N B
8 TO 14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 07 - 13, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B B OREGON N B NRN CALIF N B
SRN CALIF N N IDAHO N B NEVADA N B
W MONTANA N N E MONTANA N A WYOMING A N
UTAH N B ARIZONA N N COLORADO A N
NEW MEXICO N N N DAKOTA N A S DAKOTA N A
NEBRASKA A A KANSAS A N OKLAHOMA A B
N TEXAS A B S TEXAS N B W TEXAS A B
MINNESOTA N A IOWA N A MISSOURI A N
ARKANSAS A B LOUISIANA A N WISCONSIN N A
ILLINOIS A A MISSISSIPPI A B MICHIGAN B N
INDIANA N A OHIO N A KENTUCKY A N
TENNESSEE A N ALABAMA A B NEW YORK B N
VERMONT B N NEW HAMP B N MAINE B B
MASS B N CONN B N RHODE IS B N
PENN B N NEW JERSEY B N W VIRGINIA N A
MARYLAND N A DELAWARE N A VIRGINIA A N
N CAROLINA A N S CAROLINA A B GEORGIA N B
FL PNHDL N N FL PENIN B N AK N SLOPE A N
AK ALEUTIAN N B AK WESTERN A B AK INT BSN A B
AK S INT A B AK SO COAST N B AK PNHDL N B
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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