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FXUS06 KWBC 291918
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT MON SEPTEMBER 29 2014

6-10 DAY OUTLOOK FOR OCT 05 - 09 2014

TODAY`S MODELS ARE IN GOOD AGREEMENT ON THE FORECAST CIRCULATION FOR THE 6-10
DAY PERIOD OVER NORTH AMERICA AND VICINITY. A 500-HPA TROUGH IS PREDICTED TO BE
OVER THE EASTERN CONUS, WITH A RIDGE PREDICTED OVER THE WEST. THERE IS A
MODERATE AMOUNT OF SPREAD AMONG SOLUTIONS, WITH THE SPREAD IN THE ECMWF
ENSEMBLES HIGHER THAN THE GFS LEADING TO LOWER PREDICTED AMPLITUDES ON THE
ECMWF ENSEMBLE MEAN. SINCE THE LOW AMPLITUDE FLOW FROM THE ECMWF IS PRIMARILY
DUE TO FORECAST UNCERTAINTY, THE GEFS SOLUTION IS SLIGHTLY FAVORED DUE TO ITS
BETTER AGREEMENT AMONG MEMBERS AND ITS AGREEMENT WITH THE CANADIAN ENSEMBLES.

ABOVE-NORMAL TEMPERATURES ARE FAVORED FOR MOST OF THE WESTERN HALF OF THE
NATION, UNDER AN ANTICIPATED BROAD RIDGE OVER THE CONUS. 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. ALASKAN TEMPERATURES ARE
SOMEWHAT UNCERTAIN BECAUSE THE STATE IS EXPECTED TO BE UNDER ABOVE-NORMAL UPPER
LEVEL HEIGHTS, BUT TOOLS SHOW ELEVATED CHANCES OF BELOW-NORMAL TEMPERATURES IN
ANOMALOUS NORTHERLY UPPER LEVEL FLOW. 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. 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.

TODAY`S OFFICIAL 500-HPA BLEND CONSISTS OF 40% OF TODAY`S 6Z GFS ENSEMBLE MEAN
CENTERED ON DAY 8, 30% OF TODAY`S 0Z EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8,
AND 30% 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.

8-14 DAY OUTLOOK FOR OCT 07 - 13 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. BOTH THE ECMWF AND GEFS SURFACE
TEMPERATURE FORECAST INDICATE ABOVE-MEDIAN TEMPERATURES FOR MUCH OF THE EASTERN
CONUS, HOWEVER, A FORECAST BLOCK OVER THE NORTH ATLANTIC NEAR GREENLAND
REQUIRES CLOSE WATCHING, SINCE IT MAY ENABLE COLDER ARCTIC AIR TO ENTER THE
EASTERN TROUGH, SO PROBABILITIES FOR ABOVE-NORMAL TEMPERATURES ARE LOWER THAN
GUIDANCE SUGGESTS FOR THE EASTERN AND EAST-CENTRAL CONUS. THE 8-14 DAY
PRECIPITATION OUTLOOK IS QUITE A BIT WETTER THAN IN THE 6-10 DAY PERIOD,
SUGGESTING THAT SHORT-WAVE ENERGY DIVING INTO THE EASTERN TROUGH MAY PICK UP
SOME MOISTURE AND ELEVATE CHANCES FOR NEAR- TO ABOVE-MEDIAN PRECIPITATION
AMOUNTS OVER MUCH OF THE EASTERN CONUS. CONDITIONS FAVOR BELOW-MEDIAN
PRECIPITATION FOR THE WESTERN CONUS UNDER AN EXPECTED UPPER-LEVEL RIDGE.

TOOLS SUGGEST A CHANGE IN ALASKAN CONDITIONS BETWEEN THE 6-10 AND 8-14 DAY
PERIODS. THE SLIGHT NORTHERLY COMPONENT TO THE PREDICTED MEAN FLOW AT 500-HPA
IN THE 6-10 DAY PERIOD GIVES WAY TO SOUTHWESTERLY MEAN FLOW IN THE 8-14 DAY
PERIOD.  THIS ELEVATES CHANCES FOR ABOVE-NORMAL TEMPERATURES FOR MUCH OF ALASKA
IN THE 8-14-DAY PERIOD. THE BETTER CHANCES OF A SOUTHWESTERLY FLOW ELEVATES THE
CHANCES FOR ABOVE-MEDIAN PRECIPITATION AMOUNTS ALONG PARTS OF THE SOUTHERN
COAST OF ALASKA 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 THE UNCERTAIN AMPLITUDE OF THE TROUGH PREDICTED OVER THE EASTERN CONUS.

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 - 19511012 - 20051003 - 19690920 - 19520910


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:
20080920 - 19511011 - 19630916 - 20090908 - 20090920


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 05 - 09 2014

STATE      TEMP PCPN   STATE      TEMP PCPN   STATE      TEMP PCPN
WASHINGTON  A    N     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    A     S DAKOTA    N    N
NEBRASKA    A    B     KANSAS      A    B     OKLAHOMA    A    B
N TEXAS     A    B     S TEXAS     A    N     W TEXAS     A    B
MINNESOTA   B    N     IOWA        N    N     MISSOURI    N    B
ARKANSAS    A    B     LOUISIANA   A    B     WISCONSIN   B    N
ILLINOIS    N    B     MISSISSIPPI N    B     MICHIGAN    B    A
INDIANA     B    B     OHIO        B    N     KENTUCKY    N    B
TENNESSEE   N    B     ALABAMA     N    B     NEW YORK    N    N
VERMONT     N    N     NEW HAMP    N    N     MAINE       A    A
MASS        N    N     CONN        N    N     RHODE IS    N    N
PENN        N    N     NEW JERSEY  N    B     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    N     AK N SLOPE  A    N
AK ALEUTIAN A    B     AK WESTERN  N    B     AK INT BSN  B    B
AK S INT    B    B     AK SO COAST B    B     AK PNHDL    N    N



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR OCT 07 - 13 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   N    A     WYOMING     N    B
UTAH        A    B     ARIZONA     A    B     COLORADO    A    B
NEW MEXICO  A    B     N DAKOTA    B    A     S DAKOTA    B    A
NEBRASKA    N    N     KANSAS      N    N     OKLAHOMA    A    N
N TEXAS     A    N     S TEXAS     A    A     W TEXAS     A    B
MINNESOTA   B    A     IOWA        B    A     MISSOURI    N    N
ARKANSAS    A    N     LOUISIANA   A    A     WISCONSIN   B    A
ILLINOIS    N    N     MISSISSIPPI A    N     MICHIGAN    B    A
INDIANA     N    A     OHIO        N    A     KENTUCKY    N    A
TENNESSEE   N    N     ALABAMA     A    A     NEW YORK    A    A
VERMONT     A    A     NEW HAMP    A    N     MAINE       A    N
MASS        A    N     CONN        A    N     RHODE IS    A    N
PENN        A    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    A     GEORGIA     A    A
FL PNHDL    A    A     FL PENIN    A    A     AK N SLOPE  A    B
AK ALEUTIAN A    A     AK WESTERN  A    B     AK INT BSN  A    B
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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