The CPC's latest. No need to read all of it. Just highlighted the areas in blue that stuck out to me. As always, actions and outcomes "speak" louder than mere words from a long-range forecaster.
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD
300 PM EST FRI JANUARY 25 2013
6-10 DAY OUTLOOK FOR JAN 31 - FEB 04, 2013
TODAY'S ENSEMBLE MEAN AND HIGH-RESOLUTION RUNS ARE IN FAIRLY GOOD AGREEMENT FOR
THE UPCOMING 6-10 DAY PERIOD OVER THE PACIFIC-NORTH AMERICA REGION. THE MODELS
CONTINUE TO PREDICT AN AMPLIFIED 500-HPA FLOW PATTERN, WITH A MODERATE RIDGE
NEAR THE WEST COAST, A DEEP TROUGH ACROSS CENTRAL AND EASTERN NORTH AMERICA,
AND THE POLAR VORTEX CENTERED IN THE VICINITY OF BAFFIN AND ELLESMERE ISLANDS
IN EXTREME NORTH-CENTRAL CANADA.
MOST MODEL RUNS ALSO ANTICIPATE SPLIT FLOW OFF
THE CALIFORNIA COAST, WITH THE SOUTHERN BRANCH OF THE WESTERLIES DIRECTED
ACROSS PARTS OF THE SOUTHWESTERN CONUS AND ADJACENT NORTHERN MEXICO. IN THE
ALASKA DOMAIN, THE ECMWF-BASED SOLUTIONS AND THE 00Z CANADIAN ENSEMBLE MEAN
SUPPORT LOWERING 500-HPA HEIGHTS OVER NORTHWESTERN PORTIONS OF ALASKA,
APPARENTLY RELATED TO THE PREDICTED STRENGTHENING OF A RIDGE OVER NORTHEASTERN
SIBERIA AND THE CHUKCHI SEA. THE GFS-BASED SOLUTIONS MAINTAIN AN AMPLIFIED RIDGE WHICH EXTENDS NORTHWESTWARD ALONG THE WEST COAST OF NORTH AMERICA AND
ACROSS ALASKA.
THERE ARE ENHANCED ODDS OF BELOW-NORMAL TEMPERATURES FOR EASTERN PORTIONS OF
THE GREAT PLAINS, THE MISSISSIPPI VALLEY, AND ALL AREAS EAST TO THE ATLANTIC
COAST. THESE AREAS ROUGHLY CORRESPOND TO THE PREDICTED REGIONS OF BELOW-NORMAL 500-HPA HEIGHTS AND ANOMALOUS NORTHERLY FLOW IN THE OFFICIAL BLENDED HEIGHT PROG. ELEVATED ODDS OF ABOVE-NORMAL TEMPERATURES ARE INDICATED FOR WESTERN
PORTIONS OF WASHINGTON AND OREGON, CALIFORNIA, MUCH OF THE SOUTHERN PLATEAU,
THE SOUTHERN ROCKIES, AND THE SOUTHERN THIRD OF ALASKA. THESE AREAS ROUGHLY
CORRESPOND TO THE PREDICTED AREAS OF ABOVE-NORMAL 500-HPA HEIGHTS AND/OR
SOUTHERLY ANOMALOUS FLOW. ELSEWHERE, NEAR-NORMAL TEMPERATURES ARE FAVORED.
THERE ARE ENHANCED ODDS OF ABOVE-MEDIAN PRECIPITATION FROM THE NORTHERN
CONTINENTAL DIVIDE EASTWARD AND SOUTHEASTWARD ACROSS THE NORTHERN STATES TO THE
ATLANTIC COAST AS FAR SOUTH AS CHESAPEAKE BAY. ODDS OF ABOVE-MEDIAN
PRECIPITATION ARE ALSO ELEVATED ACROSS SOUTHWESTERN ALASKA AND THE ALASKA
PANHANDLE. THESE AREAS OF RELATIVE WETNESS ARE GENERALLY ATTRIBUTED TO
SOUTHERLY ANOMALOUS FLOW AND/OR PROXIMITY TO STORM TRACKS. THERE ARE ENHANCED
ODDS OF BELOW-MEDIAN PRECIPITATION OVER NORTHERN ALASKA, MOST OF THE PACIFIC
COAST STATES AND INTER-MOUNTAIN WEST, THE SOUTHERN ROCKIES, MOST OF THE
SOUTHERN PLAINS, AND THE LOWER MISSISSIPPI VALLEY. THE EXPECTATION FOR
BELOW-MEDIAN PRECIPITATION FOR THESE AREAS IS MAINLY DUE TO NORTHERLY ANOMALOUS
FLOW. ELSEWHERE, NEAR-MEDIAN PRECIPITATION AMOUNTS ARE FAVORED.
TODAY'S OFFICIAL 500-HPA BLEND CONSISTS OF 10 PERCENT OF TODAY'S OPERATIONAL 0Z GFS CENTERED ON DAY 8...10 PERCENT OF TODAY'S OPERATIONAL 6Z GFS CENTERED ON
DAY 8...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...10 PERCENT OF
TODAY'S OPERATIONAL 0Z ECMWF CENTERED ON DAY 8...25 PERCENT OF TODAY'S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 8...AND 15 PERCENT OF TODAY'S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 8.
MODEL OF THE DAY: ECMWF ENSEMBLE MEAN
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: ABOVE AVERAGE, 4 OUT OF 5, DUE TO
FAIRLY GOOD AGREEMENT BETWEEN MODEL RUNS.
8-14 DAY OUTLOOK FOR FEB 02 - 08 2013
TODAY'S ENSEMBLE MEAN SOLUTIONS ARE IN FAIRLY GOOD AGREEMENT ON THE PREDICTED
MID-TROPOSPHERIC FLOW PATTERN ACROSS THE PACIFIC-NORTH AMERICA DOMAIN DURING
WEEK 2. THE ENSEMBLE MEANS ANTICIPATE A RIDGE NEAR OR ALONG THE WEST COAST
WHICH EXTENDS NORTHWESTWARD ACROSS ALASKA (EXCEPT THE 00Z CANADIAN ENSEMBLE
MEAN WHICH DEPICTS A TROUGH OVER NORTHERN AND WESTERN PORTIONS OF THE STATE),
AND A DEEP TROUGH OVER EASTERN NORTH AMERICA. THIS MEAN CIRCULATION PATTERN,
SIMILAR TO THE CIRCULATION PATTERN EXPECTED FOR THE 6-10 DAY PERIOD, FAVORS
ENHANCED CHANCES OF BELOW-NORMAL TEMPERATURES ACROSS THE CENTRAL AND EASTERN CONUS. THE 00Z OPERATIONAL GFS RUN FORECASTS THE WEST COAST RIDGE ABOUT 20
DEGREES LONGITUDE OFF THE WEST COAST, WHICH FAVORS LOWERING 500-HPA HEIGHTS
OVER THE INTERIOR WEST. THE 06Z OPERATIONAL GFS SOLUTION DEPICTS A POSITIVELY
TILTED TROUGH ACROSS THE WESTERN CONUS. BOTH OF THESE SINGLE GFS RUNS WERE
GIVEN MINIMAL WEIGHTING IN THE BLEND.
THERE ARE INCREASED CHANCES OF BELOW-NORMAL TEMPERATURES FOR THE NORTHERN GREAT
PLAINS, EASTERN PORTIONS OF THE CENTRAL GREAT PLAINS, THE MISSISSIPPI VALLEY,
AND ALL REMAINING AREAS EASTWARD TO THE ATLANTIC COAST. THIS LARGE AREA OF
COVERAGE IS CONSISTENT WITH PREDICTED BELOW-NORMAL HEIGHTS AND NORTHWESTERLY
ANOMALOUS FLOW. ABOVE-NORMAL TEMPERATURES ARE FAVORED OVER SOUTHERN ALASKA,
MOST OF THE PACIFIC COAST STATES, CENTRAL AND SOUTHERN PORTIONS OF THE PLATEAU,
AND THE FAR SOUTHERN ROCKIES. THESE PREDICTED AREAS OF FAVORED ABOVE-NORMAL
SURFACE TEMPERATURES ARE GENERALLY RELATED TO SOUTHERLY ANOMALOUS FLOW AND
ABOVE-AVERAGE 500-HPA HEIGHTS. ELSEWHERE, NEAR-NORMAL TEMPERATURES ARE FAVORED.
THE ODDS FOR ABOVE-MEDIAN PRECIPITATION AMOUNTS ARE ELEVATED OVER THE NORTHERN
GREAT PLAINS, THE UPPER MISSISSIPPI VALLEY, THE GREAT LAKES REGION, MOST OF THE
OHIO VALLEY, THE APPALACHIANS, THE EAST GULF REGION, THE EAST COAST STATES, AND
SOUTHWESTERN ALASKA. THESE AREAS ARE GENERALLY ALONG THE PREDICTED LOCATION OF
THE AVERAGE STORM TRACK AND ASSOCIATED FRONTAL SYSTEMS. THE ODDS OF RECEIVING
BELOW-MEDIAN PRECIPITATION ARE ENHANCED OVER THE PACIFIC NORTHWEST, NORTHERN
CALIFORNIA, NORTHERN AND CENTRAL PORTIONS OF THE PLATEAU, MOST OF THE ROCKIES,
THE GREAT PLAINS FROM NEBRASKA SOUTHWARD INTO NORTHERN AND WESTERN TEXAS, AND
MUCH OF MISSOURI AND ARKANSAS. THIS LARGE AREA OF RELATIVE DRYNESS IS DUE
PRIMARILY TO NORTHWESTERLY ANOMALOUS FLOW. ELSEWHERE,
NEAR-MEDIAN PRECIPITATION
AMOUNTS ARE FAVORED, WHICH INCLUDES SOUTHERN PORTIONS OF CALIFORNIA AND NEVADA,
ARIZONA, AND
THE REMAINDER OF TEXAS, DUE TO THE EXPECTATION OF A SOUTHERN
BRANCH OF THE WESTERLIES STREAMING EASTWARD ACROSS THIS REGION AND INTO
NORTHERN MEXICO. THE OFFICIAL 8-14 DAY HEIGHT PROG CONSISTS OF: 5 PERCENT OF TODAY'S OPERATIONAL
0Z GFS CENTERED ON DAY 11...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...15
PERCENT OF TODAY'S 6Z GFS ENSEMBLE MEAN CENTERED ON DAY 11...20 PERCENT OF
TODAY'S GFS SUPERENSEMBLE MEAN CENTERED ON DAY 11...25 PERCENT OF TODAY'S 0Z
EUROPEAN ENSEMBLE MEAN CENTERED ON DAY 11...AND 15 PERCENT OF TODAY'S 0Z
CANADIAN ENSEMBLE MEAN CENTERED ON DAY 11.
FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD IS: NEAR AVERAGE, 3 OUT OF 5, DUE
TO NOTABLE DIFFERENCES BETWEEN THE ENSEMBLE MEANS AND THE DETERMINISTIC
SOLUTIONS.
IT IS UNCLEAR AT THIS TIME WHETHER THE PACIFIC-NORTH AMERICA (PNA)
PATTERN WILL BECOME NEGATIVE DURING THE WEEK 2 PERIOD. IF IT DOES, THE
ASSOCIATED PATTERN CHANGE WOULD THEN FAVOR A DEEPENING TROUGH OVER THE WESTERN CONUS. FORECASTER: ANTHONY ARTUSA
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