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FXUS06 KWBC 301924
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT TUE SEPTEMBER 30 2014

6-10 DAY OUTLOOK FOR OCT 06 - 10 2014

TODAY`S MODELS ARE IN FAIR AGREEMENT ON THE FORECAST CIRCULATION FOR THE 6-10
DAY PERIOD OVER NORTH AMERICA AND ADJACENT OCEAN AREAS. THERE IS GENERAL
AGREEMENT ON THE PLACEMENT OF A 500-HPA TROUGH OVER THE EASTERN CONUS, WITH A
RIDGE OVER THE WEST, AT LEAST AT THE LATITUDE OF THE MEAN POLAR JET. THE SPREAD
AMONG THE INDIVIDUAL MEMBERS OF THE ECMWF, GEFS ENSEMBLES IS CONSIDERABLY
HIGHER THAN USUAL, RESULTING IN A RATHER LOW AMPLITUDE FLOW PATTERN IN THE
MEAN.  THE CANADIAN ENSEMBLES, ON THE OTHER HAND, HAVE A LOWER SPREAD THAN
USUAL FOR THAT MODEL, AND ITS ENSEMBLE MEAN PREDICTS AN AMPLIFIED FLOW PATTERN
WITH AN EASTERN TROUGH AND WESTERN RIDGE. THE BLEND IS A FAIRLY EVEN MIX AMONG
MODELS, HOWEVER, THE HIGHER CONFIDENCE AMONG CANADIAN MEMBERS FOR AN FAIRLY
AMPLIFIED PRODUCES A HIGHER AMPLITUDE CIRCULATION IN THE BLEND THAN EITHER THE
GEFS OR ECMWF MEANS PREDICT.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE WESTERN HALF OF THE
CONUS, UNDER AN ANTICIPATED BROAD RIDGE. MODEL FORECASTS DO NOT SHOW A GREAT
DEAL OF COLD AIR ASSOCIATED WITH THE EASTERN TROUGH, SO THE CHANCES FOR
BELOW-NORMAL TEMPERATURES ARE ONLY SLIGHTLY ELEVATED NEAR THE GREAT LAKES,
WHERE MODEL AGREEMENT IS BEST. ELSEWHERE IN THE EAST, NEAR-NORMAL TEMPERATURES
ARE FAVORED, EXCEPT NEAR MAINE WHICH MAY SEE ELEVATED CHANCES OF ABOVE-NORMAL
TEMPERATURES AHEAD OF THE EASTERN TROUGH. ALASKA TEMPERATURES ARE SOMEWHAT
UNCERTAIN BECAUSE THE STATE IS EXPECTED TO BE UNDER ABOVE-NORMAL UPPER LEVEL
HEIGHTS, BUT TOOLS BASED ON MODEL PREDICTED SURFACE TEMPERATURES SHOW ELEVATED
CHANCES OF BELOW-NORMAL TEMPERATURES IN PARTS OF THE INTERIOR SOUTHEAST. THE
CHANCES OF ABOVE-NORMAL TEMPERATURES ARE ELEVATED THROUGHOUT COASTAL AREAS OF
ALASKA DUE TO ABOVE NORMAL SEA SURFACE TEMPERATURES.

TOOLS FAVOR BELOW-MEDIAN PRECIPITATION AMOUNTS FOR MUCH OF THE CONUS UNDER
NORTHWESTERLY FLOW AHEAD OF THE RIDGE EXPECTED OVER THE WEST COAST OF NORTH
AMERICA. MODELS SUGGEST AN ACTIVE JET OVER THE U.S.-CANADIAN BORDER, ELEVATING
CHANCES FOR NEAR- TO ABOVE-MEDIAN PRECIPITATION AMOUNTS.  TODAY`S PRECIPITATION
TOOLS INDICATE AN INCREASED CHANCE FOR NEAR- TO ABOVE- MEDIAN PRECIPITATION
AMOUNTS FROM TEXAS NORTHEASTWARD TO THE MIDDLE MISSISSIPPI VALLEY, SUGGESTING
AN INCREASE IN MOISTURE AVAILABILITY FOR THE CENTRAL CONUS RELATIVE TO
YESTERDAY`S OUTLOOK. THE CHANCES FOR NEAR- TO BELOW-MEDIAN PRECIPITATION
AMOUNTS ARE ENHANCED FOR MOST OF THE ALASKA MAINLAND, WITH NEAR- TO
ABOVE-MEDIAN PRECIPITATION FAVORED FOR THE PANHANDLE AND ALONG PARTS OF THE
SOUTHERN COAST AND THE SOUTHWESTERN COAST.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 40% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 10% OF TODAY`S OPERATIONAL 6Z GFS CENTERED ON DAY 8, 25% OF
TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8, AND 25% OF TODAY`S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8


MODEL OF THE DAY: 6Z GFS ENSEMBLE MEAN

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOUT AVERAGE, 3 OUT OF 5, WITH
MODELS AGREEING WELL ON THE PLACEMENT OF THE LONG WAVE FEATURES, BUT
DISAGREEMENT ON THE AMPLITUDE, AND HIGH SPREAD AMONG ECMWF AND GEFS ENSEMBLE
MEMBERS.

8-14 DAY OUTLOOK FOR OCT 08 - 14 2014

THE 8-14 DAY MEAN 500-HPA HEIGHTS FROM THE MANUAL BLEND IS QUITE SIMILAR TO THE
6-10 DAY MEAN. THIS LEADS TO A TEMPERATURE OUTLOOK FOR 8-14 DAYS THAT IS QUITE
SIMILAR TO THE 6-10 DAY PERIOD FOR THE CONUS. THE SPREAD AMONG SOLUTIONS FROM
BOTH THE ECMWF AND GEFS MODELS IS VERY HIGH, WITH MEMBERS ROUGHLY SPLIT BETWEEN
DEVELOPING A TROUGH OVER THE SOUTHWESTERN CONUS, AND PERSISTING THE TROUGH OVER
THE EAST.  THE CANADIAN MODEL ENSEMBLES CONTINUE TO FAVOR THE EASTERN TROUGH,
AS DO THE DETERMINISTIC SOLUTIONS FROM THE 6 AND 12Z GFS.  CONFIDENCE IS LOW IN
VIEW OF THE LARGE SPREAD IN TODAY`S SOLUTIONS.

TEMPERATURE TOOLS BASED ON PREDICTED NEAR-SURFACE TEMPERATURES SUGGEST ELEVATED
CHANCES FOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE WESTERN AND SOUTHERN
CONUS, AND ALONG THE EASTERN SEABOARD. CONFIDENCE IS LOW IN THIS FORECAST,
HOWEVER, WITH CONSIDERABLE MODEL SPREAD. BELOW-NORMAL TEMPERATURES ARE FAVORED
FOR PARTS OF THE NORTHERN GREAT PLAINS, THE UPPER MISSISSIPPI VALLEY AND UPPER
GREAT LAKES ASSOCIATED WITH A PREDICTED TROUGH. SOUTHWESTERLY MEAN FLOW IN THE
8-14 DAY PERIOD ELEVATES CHANCES FOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF
ALASKA AND ELEVATES THE CHANCES FOR ABOVE-MEDIAN PRECIPITATION AMOUNTS ALONG
PARTS OF THE SOUTHERN COAST OF ALASKA, SOUTHWESTERN PARTS OF THE STATE, AND THE
PANHANDLE.

THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 40% OF TODAY`S 6Z GFS ENSEMBLE
MEAN CENTERED ON DAY 11, 30% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON
DAY 11, AND 30% OF TODAY`S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11


FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: BELOW AVERAGE, 2 OUT OF 5, DUE
TO HIGH ENSEMBLE SPREAD AMONG GEFS AND CANADIAN MEMBERS.

FORECASTER: DAVE UNGER

NOTES:


AUTOMATED FORECASTS ARE ISSUED ON SATURDAY AND SUNDAY. OCCASIONALLY MANUAL
INTERVENTION IS NECESSARY TO ADDRESS QUALITY CONTROL AND CONSISTENCY ISSUES.
IN THESE CASES, FORECASTS ARE MANUALLY DRAWN BUT A FULL DISCUSSION IS NOT
ISSUED.

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

THE TEMPERATURE MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING WARMER
(ORANGE, "A"), COLDER (BLUE, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL AVERAGE VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "F").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

THE PRECIPITATION MAP SHOWS REGIONS WITH > 33% CHANCE OF BEING
WETTER (GREEN, "A"), DRIER (TAN, "B"), OR CLOSE TO (UNSHADED, "N")
HISTORICAL MEDIAN VALUES FOR THE CALENDAR PERIOD OF THE FORECAST
(DASHES, "INCHES").  LABELS ON THE SHADED LINES GIVE THE PROBABILITY
(> 33%) OF THE MORE LIKELY CATEGORY (B OR A).  PROBABILITY OF N IS
ALWAYS < 40%.

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 CLIMATE PREDICTION CENTER USES 1981-2010 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
OCTOBER 16

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:
20080921 - 19511013 - 19520910 - 19690920 - 19631003


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 7 DAY PERIODS CENTERED ON THE FOLLOWING DATES:
19511012 - 20080920 - 19520909 - 19820928 - 19571011


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 06 - 10 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    B
SRN CALIF   A    N     IDAHO       A    B     NEVADA      A    B
W MONTANA   A    N     E MONTANA   A    A     WYOMING     A    B
UTAH        A    B     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    N    N     S DAKOTA    N    B
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   B    N     IOWA        N    A     MISSOURI    N    A
ARKANSAS    A    N     LOUISIANA   A    N     WISCONSIN   B    A
ILLINOIS    N    A     MISSISSIPPI A    B     MICHIGAN    B    A
INDIANA     B    A     OHIO        B    N     KENTUCKY    N    N
TENNESSEE   N    B     ALABAMA     N    B     NEW YORK    N    A
VERMONT     N    A     NEW HAMP    N    A     MAINE       A    A
MASS        N    N     CONN        N    N     RHODE IS    N    N
PENN        N    N     NEW JERSEY  N    N     W VIRGINIA  N    B
MARYLAND    N    B     DELAWARE    N    B     VIRGINIA    N    B
N CAROLINA  N    B     S CAROLINA  N    B     GEORGIA     N    B
FL PNHDL    N    B     FL PENIN    N    B     AK N SLOPE  A    B
AK ALEUTIAN A    A     AK WESTERN  A    B     AK INT BSN  N    B
AK S INT    N    N     AK SO COAST N    A     AK PNHDL    N    A



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 08 - 14 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    B     OREGON      A    B     NRN CALIF   A    B
SRN CALIF   A    N     IDAHO       A    B     NEVADA      A    B
W MONTANA   N    N     E MONTANA   B    A     WYOMING     N    B
UTAH        A    B     ARIZONA     A    N     COLORADO    A    B
NEW MEXICO  A    N     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    N     KANSAS      N    N     OKLAHOMA    A    A
N TEXAS     A    A     S TEXAS     A    A     W TEXAS     A    N
MINNESOTA   B    A     IOWA        B    A     MISSOURI    N    A
ARKANSAS    A    A     LOUISIANA   A    A     WISCONSIN   B    A
ILLINOIS    N    A     MISSISSIPPI A    A     MICHIGAN    B    A
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    A     ALABAMA     A    A     NEW YORK    A    A
VERMONT     A    A     NEW HAMP    A    N     MAINE       A    A
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        N    A     NEW JERSEY  A    N     W VIRGINIA  N    A
MARYLAND    A    N     DELAWARE    A    N     VIRGINIA    A    N
N CAROLINA  A    N     S CAROLINA  A    N     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  A    N
AK ALEUTIAN A    A     AK WESTERN  A    A     AK INT BSN  A    N
AK S INT    A    A     AK SO COAST A    A     AK PNHDL    A    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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