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FXUS06 KWBC 211901
PMDMRD
PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT MON JUL 21 2008
6-10 DAY OUTLOOK VALID FOR JUL 27 - 31 2008
TODAYS AVAILABLE ENSEMBLE MEAN FORECASTS ARE IN GOOD AGREEMENT ON THE EXPECTED
500-HPA FLOW PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD. THE PATTERN IS
FORECAST TO BE UNUSUALLY AMPLIFIED FOR THIS TIME OF YEAR WITH TROUGHS PROGGED
OVER THE EASTERN THIRD OF THE CONUS AND ALASKA/GULF OF ALASKA, AND A RIDGE OVER
THE SOUTHWEST EXTENDING NORTHWARD TO OVER THE NORTHERN ROCKIES/NORTHERN PLAINS
AND INTO CENTRAL CANADA. THE MOST RECENT SOLUTIONS OF THE OPERATIONAL GFS AND
OPERATIONAL ECMWF ARE IN GOOD AGREEMENT WITH THE ENSEMBLE MEAN PROGS WITH ONLY
SLIGHT DIFFERENCES IN AMPLITUDE AND PHASE OF THE MAIN CIRCULATION FEATURES. THE
MODELS GENERALLY SHOW GOOD CONTINUITY WITH RESPECT TO THEIR PREVIOUS SOLUTIONS
ALTHOUGH THE MOST RECENT OPERATIONAL PROGS ARE A BIT LESS PROGRESSIVE WITH THE
EASTERN TROUGH. TODAYS BLEND CHART INDICATES BELOW NORMAL HEIGHTS OVER THE
EASTERN THIRD OF THE CONUS, THE SOUTHERN TIER OF THE COUNTRY, ALONG THE WEST
COAST, AND MOST OF ALASKA, WHILE ABOVE NORMAL HEIGHTS ARE PROGGED OVER THE
NORTHERN AND CENTRAL ROCKIES, NORTHERN AND CENTRAL PLAINS, THE CENTRAL GREAT
BASIN AND THE ALEUTIANS. THE TROUGH OVER THE EASTERN CONUS LEADS TO A FORECAST
OF NEAR TO BELOW NORMAL TEMPERATURES OVER THE EASTERN HALF OF THE COUNTRY WHILE
THE WESTERN RIDGE LEADS TO NEAR TO ABOVE NORMAL TEMPERATURES OVER THE WESTERN
HALF OF THE COUNTRY. THE TROUGH OVER ALASKA CAUSES BELOW NORMAL TEMPERATURES
ACROSS MOST OF THE STATE. THE EASTERN TROUGH PRODUCES ABOVE MEDIAN
PRECIPITATION ALONG THE EAST COAST WHILE SUBSIDENCE ON THE REARSIDE OF THE
TROUGH LEADS TO BELOW MEDIAN PRECIPITATION OVER THE GREAT LAKES AND MUCH OF THE
MISSISSIPPI VALLEY. MESOSCALE CONVECTIVE ACTIVITY LEADS TO ABOVE MEDIAN
PRECIPITATION OVER PARTS OF THE NORTHERN AND CENTRAL PLAINS WHILE MONSOONAL
PRECIPITATION CAUSES ABOVE MEDIAN PRECIPITATION OVER THE SOUTHWEST/SOUTHERN
ROCKIES. ABOVE MEDIAN PRECIPITATION IS FORECAST OVER THE PANHANDLE OF ALASKA
DUE TO ANOMALOUS SOUTHERLY FLOW IN ADVANCE OF THE GULF OF ALASKA TROUGH. MUCH
OF THE REST OF ALASKA IS FORECAST TO HAVE BELOW MEDIAN PRECIPITATION DUE TO
ANOMALOUS NORTHERLY FLOW ON THE REARSIDE OF THE GULF OF ALASKA TROUGH.
TODAYS OFFICIAL 500-HPA BLEND CONSISTS OF 10 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...15 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 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 AND ANALOG SPECIFICATIONS
FROM THE OFFICIAL BLEND, KLEIN PROBABILITIES FROM THE VARIOUS ENSEMBLES, AND
THE CPC AUTO BLEND FORECAST.
THE 6-10 DAY PRECIPITATION PROG IS BASED ON THE ANALOG SPECIFICATIONS FROM THE
OFFICIAL BLEND, THE NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS)
PRECIPITATION TOOL, INSPECTION OF DAILY PRECIPITATION FORECASTS FROM THE
VARIOUS MODELS AND THE CPC AUTO BLEND PRECIPITATION FORECAST.
8-14 DAY OUTLOOK FOR JUL 29 - AUG 04, 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. THE 0Z AND 6Z OPERATIONAL GFS ARE IN
BASICALLY GOOD AGREEMENT WITH THE ENSEMBLE MEAN SOLUTIONS ALTHOUGH THE
OPERATIONAL RUNS HOLD MORE TROUGH ENERGY BACK OVER THE LOWER MISSISSIPPI VALLEY
COMPARED TO THE ENSEMBLE MEAN SOLUTIONS. THE MODELS GENERALLY SHOW GOOD
CONTINUITY WITH RESPECT TO THEIR SOLUTIONS FROM YESTERDAY ALTHOUGH TODAYS
OPERATIONAL 0Z GFS HOLDS MORE TROUGH BACK OVER THE EASTERN CONUS COMPARED TO
ITS SOLUTION FROM YESTERDAY. THIS CHANGE PUTS TODAYS 0Z OPERATIONAL GFS IN
BETTER AGREEMENT WITH THE LATEST ENSEMBLE MEAN SOLUTIONS. TODAYS BLEND CHART
INDICATES NEAR TO BELOW NORMAL HEIGHTS OVER THE EAST COAST, THE TENNESSEE
VALLEY, CENTRAL AND SOUTHERN MISSISSIPPI VALLEY, THE SOUTHERN PLAINS, PACIFIC
NORTHWEST AND MOST OF ALASKA WHILE ABOVE NORMAL HEIGHTS ARE PROGGED OVER THE
REMAINDER OF THE CONUS AND THE WESTERN ALEUTIANS. THE TEMPERATURE AND
PRECIPITATION ANOMALY PATTERNS FOR WEEK 2 ARE LITTLE CHANGED FROM THOSE
DEPICTED FOR THE 6-10 DAY PERIOD ALTHOUGH THE AREA OF ABOVE NORMAL TEMPERATURES
FORECAST OVER THE PLAINS DURING THE 6-10 DAY PERIOD EXPANDS EASTWARD DURING
WEEK 2.
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 5 PERCENT OF TODAY'S OPERATIONAL
0Z GFS CENTERED ON DAY 11...10 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED
ON DAY 11...15 PERCENT OF TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...25
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 15 PERCENT OF TODAY'S
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS ABOVE AVERAGE, 4 ON A SCALE OF 1
TO 5 DUE TO GOOD 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 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, 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:
19800731 - 19910801 - 19580804 - 19640704 - 19730703
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 - 19840709 - 19690727 - 19630717 - 19730703
6 TO 10 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 27 - 31, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N N OREGON A N NRN CALIF A N
SRN CALIF A N IDAHO A N NEVADA A N
W MONTANA A N E MONTANA A N WYOMING A N
UTAH A N ARIZONA A N COLORADO A A
NEW MEXICO A A N DAKOTA A A S DAKOTA A A
NEBRASKA A A KANSAS N N OKLAHOMA N B
N TEXAS N B S TEXAS N N W TEXAS A B
MINNESOTA A N IOWA N A MISSOURI N N
ARKANSAS B N LOUISIANA B A WISCONSIN N B
ILLINOIS B B MISSISSIPPI B A MICHIGAN B B
INDIANA B B OHIO B B KENTUCKY B B
TENNESSEE B N ALABAMA B A NEW YORK B A
VERMONT N A NEW HAMP N A MAINE N A
MASS N 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 B A AK N SLOPE N N
AK ALEUTIAN B B AK WESTERN B B AK INT BSN N B
AK S INT B B AK SO COAST B B AK PNHDL B A
8 TO 14 DAY OUTLOOK TABLE
OUTLOOK FOR JUL 29 - 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 N 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 N A N DAKOTA A A S DAKOTA A N
NEBRASKA A N KANSAS A B OKLAHOMA N B
N TEXAS B B S TEXAS B N W TEXAS N B
MINNESOTA A A IOWA A A MISSOURI N N
ARKANSAS B B LOUISIANA B A WISCONSIN A A
ILLINOIS N N MISSISSIPPI B A MICHIGAN A B
INDIANA N B OHIO N B KENTUCKY B N
TENNESSEE B N ALABAMA B A NEW YORK N N
VERMONT A N NEW HAMP N N MAINE N N
MASS N N 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 A
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N N AK N SLOPE N N
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B N
AK S INT B B AK SO COAST B B 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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