665
FXUS06 KWBC 181900
PMDMRD
PROGNOSTIC DISCUSSIONS FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER CAMP SPRINGS MD
300 PM EDT MON AUG 18 2008
6-10 DAY OUTLOOK VALID FOR AUG 24 - 28 2008
TODAYS AVAILABLE ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE
EXPECTED 500-HP FLOW PATTERN OVER NORTH AMERICA FOR THE 6-10 DAY PERIOD.
TROUGHS ARE FORECAST OVER WESTERN ALASKA, THE GULF OF ALASKA, AND NEAR THE
GREAT LAKES WHILE A SUBTROPICAL RIDGE IS PROGGED OVER THE SOUTHWEST CONUS.
TODAYS OPERATIONAL 6Z GFS AND YESTERDAYS 12Z OPERATIONAL ECMWF ARE CONSIDERABLY
MORE AMPLIFIED WITH THE TROUGH FORECAST NEAR THE GREAT LAKES CONMPARED TO THE
ENSEMBLE MEAN SOLUTIONS, WHILE THE 0Z OPERATIONAL GFS SHOWS SIMILAR AMPLITUDE
BUT IS MORE PROGRESSIVE WITH THIS FEATURE. THE MODELS SHOW FARILY GOOD
CONTINUITY WITH RESPECT TO THEIR PREVIOUS SOLUTIONS ALTHOUGH TODAYS 0Z
OPERATIONAL GFS IS MORE PROGRESSIVE WITH THE TROUGH OVER THE GREAT LAKES AND
TODAYS 6Z OPERATIONAL GFS IS MORE AMPLIFIED WITH THIS FEATURE. TODAYS BLEND
CHART INDICATES NEAR TO BELOW NORMAL 500-HPA HEIGHTS OVER MOST OF THE EASTERN
TWO THIRDS OF THE CONUS, EXCEPT OVER THE NORTHEAST WHERE NEAR TO ABOVE NORMAL
HEIGHTS ARE FORECAST. THE WESTERN THIRD OF THE CONUS IS FORECAST TO HAVE NEAR
TO ABOVE NORMAL HEIGHTS WHILE ALASKA IS PROGGED TO HAVE BELOW NORMAL HEIGHTS.
THE AREA OF BELOW NORMAL HEIGHTS OVER THE EAST SHOULD LEAD TO BELOW NORMAL
TEMPERATURES FOR MUCH OF THE SOUTHEASTERN CONUS WHILE ABOVE NORMAL HEIGHTS OVER
THE NORTHEAST LEADS TO ABOVE NORMAL TEMPERATURES FOR THAT REGION. LIKEWISE THE
AREA OF ABOVE NORMAL HEIGHTS OVER THE WEST SHOULD LEAD TO ABOVE NORMAL
TEMPERATURES FOR MUCH OF THE WESTERN CONUS. THE TROUGH OVER ALASKA SHOULD CAUSE
MOST OF THE STATE TO HAVE BELOW NORMAL TEMPERATURES. THE TROUGH OVER THE GREAT
LAKES SHOULD LEAD TO ABOVE MEDIAN PRECIPITATION FOR MUCH OF THE EAST AND GULF
COASTS, WHILE THE RIDGE OVER THE SOUTHWEST SHOULD CAUSE BELOW MEDIAN
PRECIPITATION OVER MUCH OF THE WESTERN CONUS. THE TROUGH OVER THE GULF OF
ALASKA SHOULD LEAD TO ABOVE MEDIAN PRECIPITATION FOR THE ALASKAN PANHANDLE.
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...15 PERCENT OF
TODAY'S 0Z GFS ENSEMBLE MEAN CENTERED ON DAY 8...25 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 30 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 FAIRLY GOOD AGREEMENT AMONG THE TOOLS.
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 THE CDC
CALIBRATED TEMPERATURE FORECAST.
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, AND THE DAILY FORECASTS FROM THE MOST RECENT GFS AND ECMWF MODEL
RUNS.
8-14 DAY OUTLOOK FOR AUG 26 - SEP 01, 2008:
FOR WEEK 2 THE GFS AND CANADIAN ENSEMBLE MEANS DEPICT A FLOW PATTERN WHICH IS
VERY SIMILAR TO THAT FORECAST FOR THE 6-10 DAY PERIOD. THE 0Z AND 6Z
OPERATIONAL GFS ARE MORE AMPLIFIED WITH THE TROUGH OVER THE EASTERN CONUS
COMPARED TO THE ENSEMBLE MEAN SOLUTIONS. IN ADDITION, THE 6Z OPERATIONAL GFS
AMPLIFIES A TROUGH OVER NORTHERN CALIFORNIA WHICH IS NOT DEPICTED IN THE OTHER
MODEL SOLUTIONS. THE ENSEMBLE MEAN SOLUTIONS SHOW FAIRLY GOOD CONTINUITY WITH
RESPECT TO THEIR PREVIOUS FORECASTS. TODAYS OPERATIONAL 0Z GFS IS MORE
PROGRESSIVE WITH THE TROUGH OVER THE EASTERN CONUS AND MORE AMPLIFIED WITH THE
RIDGE OVER THE SOUTHWEST COMPARED TO ITS SOLUTION FROM YESTERDAY. TODAYS 6Z
OPERATIONAL GFS IS LESS PROGRESSIVE WITH THE EASTERN TROUGH AND DEPICTS A
TROUGH OVER CALIFORNIA WHERE YESTERDAY IT HAD FORECAST AN AMPLIFIED RIDGE. FOR
THESE REASONS TODAYS OPERATIONAL GFS FORECASTS WERE MOSTLY DISCOUNTED. THE
EXPECTED TEMPERATURE AND PRECIPITATION ANOMALY PATTERNS FOR WEEK 2 ARE LITTLE
CHANGED FROM THOSE FORECAST FOR THE 6-10 DAY PERIOD.
THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF 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...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 25 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 BUT RELATIVELY POOR AGREEMENT AMONG
THE FORECAST TOOLS.
THE 8-14 DAY TEMPERATURE PROG IS BASED ON THE KLEIN AND NEURAL NET
SPECIFICATIONS FROM THE OFFICIAL BLEND, THE AUTO TEMPERATURE FORECAST, THE
NORTH AMERICAN ENSEMBLE FORECAST SYSTEM (NAEFS) TEMPERATURE PROBABILITY
FORECASTS, THE CDC CALIBRATED TEMPERATURE FORECAST, 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, AND NERUAL NET PROBABLIITIES FROM THE GFS AND CANADIAN
ENSEMBLES.
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:
19980901 - 19550831 - 19880901 - 19810806 - 19670831
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:
19550831 - 19980831 - 19810806 - 19670831 - 19710825
6 TO 10 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 24 - 28, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON N N OREGON A B NRN CALIF A N
SRN CALIF A N IDAHO A B NEVADA A B
W MONTANA A B E MONTANA A B WYOMING A B
UTAH A B ARIZONA A B COLORADO N B
NEW MEXICO N B N DAKOTA A B S DAKOTA N B
NEBRASKA N B KANSAS B B OKLAHOMA B B
N TEXAS B N S TEXAS B A W TEXAS N N
MINNESOTA A B IOWA N B MISSOURI B B
ARKANSAS B N LOUISIANA B A WISCONSIN N B
ILLINOIS B N MISSISSIPPI B A MICHIGAN N N
INDIANA B N OHIO B N KENTUCKY B N
TENNESSEE B A ALABAMA B A NEW YORK A A
VERMONT A A NEW HAMP A A MAINE A A
MASS A A CONN A A RHODE IS A A
PENN N A NEW JERSEY N A W VIRGINIA B 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 B B
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B N
AK S INT B A AK SO COAST B A AK PNHDL B A
8 TO 14 DAY OUTLOOK TABLE
OUTLOOK FOR AUG 26 - SEP 01, 2008
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN
WASHINGTON B B OREGON N B NRN CALIF A B
SRN CALIF A N IDAHO N B NEVADA A B
W MONTANA B N E MONTANA N N WYOMING N B
UTAH A B ARIZONA A B COLORADO N B
NEW MEXICO A B N DAKOTA A N S DAKOTA N B
NEBRASKA N B KANSAS N B OKLAHOMA B B
N TEXAS B N S TEXAS N A W TEXAS N N
MINNESOTA A N IOWA N B MISSOURI B B
ARKANSAS B N LOUISIANA B A WISCONSIN A B
ILLINOIS N B MISSISSIPPI B A MICHIGAN N N
INDIANA N N OHIO N N KENTUCKY B N
TENNESSEE B N ALABAMA B A NEW YORK A N
VERMONT A N NEW HAMP A A MAINE A A
MASS A A CONN A A RHODE IS A A
PENN A N NEW JERSEY A A W VIRGINIA N N
MARYLAND A A DELAWARE A A VIRGINIA N A
N CAROLINA B A S CAROLINA B A GEORGIA B A
FL PNHDL B A FL PENIN N A AK N SLOPE N A
AK ALEUTIAN B N AK WESTERN B N 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.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page