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FXUS06 KWBC 011940
PMDMRD
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EDT WED APRIL 01 2015

6-10 DAY OUTLOOK FOR APR 07 - 11 2015

TODAY`S MODELS CONTINUE TO BE IN GOOD AGREEMENT ON THE EXPECTED MEAN 500-HPA
HEIGHTS FOR THE 6-10 DAY PERIOD. MODELS PREDICT A STRONG PACIFIC JET SEPARATING
INTO A SOUTHERN AND NORTHERN STREAM AS IT APPROACHES THE WEST COAST OF NORTH
AMERICA. A TROUGH IS PREDICTED OVER THE SOUTHWESTERN CONUS IN ASSOCIATION WITH
THE SOUTHERN JET, WHILE THE NORTHERN JET DIVERTS OVER A RIDGE PREDICTED OVER
WESTERN CANADA. THE TWO STREAMS CONVERGE INTO A FAIRLY DEEP TROUGH PREDICTED TO
BE OVER OR JUST EAST OF THE CANADIAN MARITIME PROVINCES. THIS IS LIKELY TO
PRODUCE AN ACTIVE WEATHER PATTERN FOR CENTRAL AND EASTERN CONUS, WITH WARM,
MOIST AIR BEING PUSHED INTO THE EAST-CENTRAL CONUS AHEAD OF THE SOUTHERN JET,
WHILE COLD AIR REMAINS ENTRENCHED OVER EASTERN CANADA ASSOCIATED WITH NORTHERN
JET. THERE IS GOOD AGREEMENT AMONG MODELS AND ENSEMBLES FOR A FAIRLY DEEP MEAN
TROUGH TO BE OVER WESTERN ALASKA DURING THE 6-10 DAY PERIOD.

THE FORECAST RIDGE OVER THE SOUTHEASTERN CONUS ELEVATES THE CHANCES FOR
ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE EASTERN AND CENTRAL CONUS.
TEMPERATURES NEAR THE MID-ATLANTIC STATES AND THE OHIO VALLEY ARE UNCERTAIN DUE
TO THE POSSIBILITY OF COLD AIR FROM EASTERN CANADA PUSHING INTO THE REGION
UNDER THE INFLUENCE OF THE NORTHERN JET. TEMPERATURE ANOMALIES IN THE WESTERN
CONUS ARE GENERALLY FORECAST TO BE SMALL, LEADING TO SLIGHTLY ELEVATED CHANCES
OF BELOW-NORMAL MEAN TEMPERATURES IN PARTS OF THE GREAT BASIN AND SOUTHWEST,
NEAR THE PREDICTED SOUTHWESTERN TROUGH. ABOVE-NORMAL TEMPERATURES ARE FAVORED
IN SOUTHERN ALASKA UNDER SOUTHWESTERLY FLOW ALOFT, WHILE THE CHANCES OF NEAR-
TO BELOW-NORMAL TEMPERATURES ARE ELEVATED IN CENTRAL AND NORTHERN PARTS OF THE
STATE NEAR THE EXPECTED 500-HPA TROUGH.

ABOVE-MEDIAN PRECIPITATION AMOUNTS ARE STRONGLY FAVORED IN PARTS OF THE OHIO
AND TENNESSEE RIVER VALLEYS ALONG AN EXPECTED FRONTAL BOUNDARY WITH A GOOD
MOISTURE SUPPLY EXPECTED FROM THE GULF OF MEXICO. THE CHANCES OF ABOVE-MEDIAN
PRECIPITATION ARE ELEVATED ALONG THE WEST COAST NEAR THE ACTIVE SOUTHERN JET,
AND IN SOUTHERN AND CENTRAL ALASKA NEAR THE NORTHERN BRANCH OF THE PACIFIC JET.
BELOW-MEDIAN PRECIPITATION IS FAVORED OVER THE ROCKIES AND HIGH PLAINS AS THE
MAIN STORM TRACK IS DIVERTED SOUTHWARD NEAR THE REGION.

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 GEFS ENSEMBLE MEAN.

FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
GOOD AGREEMENT AMONG MODEL ENSEMBLES AND GOOD AGREEMENT AMONG TEMPERATURE AND
PRECIPITATION TOOLS.

8-14 DAY OUTLOOK FOR APR 09 - 15 2015

THE PREDICTED 500-HPA CIRCULATION FOR WEEK-2 IS VERY SIMILAR TO THE 6-10 DAY
FORECAST, WITH PERHAPS A TREND TOWARDS A MORE ZONAL PATTERN. THE MORE ZONAL
500-HPA FLOW PATTERN MAY WEAKEN THE TEMPERATURE GRADIENTS OVER THE EAST, AND
FAVORS AN EXPANSION OF THE AREA OF EXPECTED ABOVE-NORMAL TEMPERATURES INTO THE
UPPER MISSISSIPPI VALLEY. CONDITIONS FAVOR THE PERSISTENCE OF BELOW-NORMAL
TEMPERATURES IN THE NORTHEAST AND NEAR THE EASTERN GREAT LAKES. TEMPERATURES
BASED ON CALIBRATED FORECASTS OF NEAR-SURFACE MODEL TEMPERATURES SLIGHTLY FAVOR
ABOVE-NORMAL TEMPERATURES FOR MUCH OF THE WEST IN WEAK-ZONAL FLOW. BELOW NORMAL
SNOW COVER MAY HELP ELEVATE CHANCES FOR ABOVE NORMAL TEMPERATURES IN HIGHER
TERRAIN, AND ABOVE-NORMAL SEA-SURFACE TEMPERATURES MAY ENHANCE CHANCES FOR
ABOVE-NORMAL TEMPERATURES ALONG THE PACIFIC COAST. THE CHANCES OF
BELOW-TEMPERATURES ARE ELEVATED IN MOST OF ALASKA EXCEPT ALONG THE SOUTH COAST
WHERE NEAR- NORMAL TEMPERATURES ARE FAVORED, AND ALONG THE PANHANDLE WHERE
ABOVE NORMAL SEA SURFACE TEMPERATURES MAY ENHANCE CHANCES OF ABOVE-NORMAL
TEMPERATURES IN COASTAL AREAS.

THE PRECIPITATION OUTLOOK IS QUITE SIMILAR TO THAT OF THE 6-10 DAY PERIOD, WITH
ABOVE-MEDIAN PRECIPITATION AMOUNTS FAVORED THROUGHOUT MUCH OF THE EASTERN AND
EAST-CENTRAL CONUS, AND BELOW-MEDIAN PRECIPITATION FAVORED FOR PARTS OF THE
CENTRAL AND NORTHERN ROCKIES AND THE NORTHERN GREAT PLAINS. ABOVE-MEDIAN
PRECIPITATION AMOUNTS ARE FAVORED ALONG MUCH OF THE WEST COAST ASSOCIATED WITH
THE WESTERN TROUGH. THERE CONTINUES TO BE CONSIDERABLE UNCERTAINTY IN THE
PRECIPITATION FORECAST FOR THE SOUTHWESTERN CONUS, WITH THE CHANCES OF
ABOVE-MEDIAN PRECIPITATION SLIGHTLY HIGHER THAN ON YESTERDAY`S OUTLOOK OVER
PARTS OF THE SOUTHERN ROCKIES. A TROUGH PREDICTED OVER WESTERN ALASKA ELEVATES
THE CHANCES FOR ABOVE-MEDIAN PRECIPITATION FOR SOUTHERN PARTS OF THE STATE.

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: ABOVE AVERAGE, 4 OUT OF 5, DUE
TO GOOD MODEL AND TOOL AGREEMENT.

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
APRIL 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:
19600408 - 19850410 - 19600321 - 19880319 - 19780329


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:
19600408 - 19600324 - 19850410 - 19770407 - 19950402


6-10 DAY OUTLOOK TABLE
OUTLOOK FOR APR 07 - 11 2015

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



8-14 DAY OUTLOOK TABLE
OUTLOOK FOR APR 09 - 15 2015

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