575  
FXUS06 KWBC 052002  
PMDMRD  
PROGNOSTIC DISCUSSION FOR 6 TO 10 AND 8 TO 14 DAY OUTLOOKS  
NWS CLIMATE PREDICTION CENTER COLLEGE PARK, MD  
300 PM EST FRI DECEMBER 05 2025  
 
6-10 DAY OUTLOOK FOR DEC 11 - 15 2025  
 
TODAY'S NUMERICAL MODELS ARE IN GOOD AGREEMENT IN DEPICTING A VERY AMPLIFIED  
500-HPA FLOW PATTERN ACROSS NORTH AMERICA AND VICINITY. AN UNUSUALLY STRONG  
RIDGE (WITH POSITIVE HEIGHT DEPARTURES GREATER THAN 390 METERS) IS FORECAST  
OVER THE BERING SEA. DOWNSTREAM TROUGHING IS FORECAST OVER SOUTHEASTERN ALASKA  
AND A STRONG RIDGE IS FORECAST OVER THE WESTERN CONUS. LARGE SCALE ANOMALOUS  
TROUGHING IS FORECAST OVER MOST OF EASTERN NORTH AMERICA. THIS OVERALL PATTERN  
IS VERY SIMILAR TO THAT FORECAST YESTERDAY, WITH TODAY'S SOLUTION REPRESENTING  
EVEN MORE AMPLIFICATION OF THE LARGE SCALE FEATURES. FARTHER AWAY FROM NORTH  
AMERICA, SLIGHTLY BELOW NORMAL 500-HPA HEIGHTS ARE FORECAST FOR HAWAII, ON THE  
SOUTHERN FRINGE OF BROADLY CYCLONIC FLOW OVER THE CENTRAL PACIFIC.  
 
BELOW NORMAL TEMPERATURES ARE LIKELY ACROSS MUCH OF THE EASTERN AND  
NORTH-CENTRAL CONUS DUE TO STRONG AND PERSISTENT TROUGHING. PROBABILITIES OF  
BELOW NORMAL TEMPERATURES EXCEED 80 PERCENT ACROSS MUCH OF THE GREAT LAKES  
REGION AND ADJACENT AREAS OF THE NORTHEAST AND NORTHERN MID-ATLANTIC.  
CONVERSELY, EXPANSIVE RIDGING ACROSS THE WEST FAVORS ABOVE NORMAL TEMPERATURES.  
WITH THIS RIDGE COMING IN STRONGER TODAY RELATIVE TO YESTERDAY, CHANCES OF  
WARMER THAN NORMAL TEMPERATURES EXCEED 90 PERCENT FOR PARTS OF THE GREAT BASIN  
AND ADJACENT AREAS OF THE SOUTHWEST. CONVERSELY, A COLD PATTERN IS LIKELY FOR  
MUCH OF ALASKA DUE TO ANOMALOUS NORTHERLY FLOW AHEAD OF THE PREDICTED UNUSUALLY  
STRONG BERING SEA RIDGE. CHANCES OF BELOW NORMAL TEMPERATURES ARE GREATER THAN  
80 PERCENT FOR SOUTHEAST ALASKA AND ADJACENT AREAS OF THE SOUTHEASTERN  
MAINLAND. ABOVE NORMAL TEMPERATURES ARE FAVORED FOR HAWAII, CONSISTENT WITH  
DYNAMICAL MODEL OUTPUT AND WITH ABOVE NORMAL SSTS IN THE ADJACENT PACIFIC.  
 
AN ACTIVE PATTERN IS FAVORED FOR THE NORTHWESTERN AND NORTH-CENTRAL CONUS AS  
ENHANCED PACIFIC FLOW IS FORECAST AHEAD OF A MEAN TROUGH FORECAST NEAR  
SOUTHEASTERN ALASKA. BELOW NORMAL PRECIPITATION IS LIKELY ACROSS MOST OF THE  
SOUTHERN TWO-THIRDS OF THE CONUS DUE TO A COMBINATION OF ANOMALOUS MID-LEVEL  
RIDGING ACROSS MUCH OF THE WEST AND MEAN SURFACE HIGH PRESSURE ACROSS MUCH OF  
THE EAST. THE AREA OF FAVORED BELOW NORMAL PRECIPITATION EXTENDS NORTHWARD  
ALONG MUCH OF THE EASTERN SEABOARD AS A SURFACE LOW DEPARTS OFFSHORE OF NEW  
ENGLAND NEAR THE START OF THE PERIOD. IN THE WAKE OF THIS SYSTEM, STRONG  
NORTHERLY OR NORTHWESTERLY LOW-LEVEL FLOW IS FORECAST OVER THE GREAT LAKES,  
SETTING UP THE POTENTIAL FOR ENHANCED LAKE EFFECT SNOW. A TILT TOWARD ABOVE  
NORMAL PRECIPITATION IS INDICATED FOR MUCH OF THE GREAT LAKES REGION DUE TO  
THIS POTENTIAL. FARTHER TO THE SOUTH, A SLIGHT TILT TOWARD ABOVE NORMAL  
PRECIPITATION IS INDICATED FOR EXTREME SOUTHERN FLORIDA AND SOUTHERN TEXAS,  
NEAR THE SOUTHERN PERIPHERY OF THE PREDICTED TROUGH OVER EASTERN NORTH AMERICA.  
CONVERSELY, BELOW NORMAL PRECIPITATION IS LIKELY FOR MUCH OF ALASKA CONSISTENT  
WITH PREDICTED NORTHERLY OFFSHORE FLOW AHEAD OF THE VERY STRONG RIDGE OVER THE  
BERING SEA. ABOVE NORMAL PRECIPITATION IS FAVORED FOR HAWAII NEAR THE SOUTHERN  
PERIPHERY OF PREDICTED BROAD CYCLONIC FLOW OVER THE CENTRAL PACIFIC AND  
CONSISTENT WITH DYNAMICAL MODEL GUIDANCE.  
 
THE OFFICIAL 6-10 DAY 500-HPA HEIGHT BLEND CONSISTS OF 30% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 8, 40% OF TODAY'S 0Z EUROPEAN ENSEMBLE MEAN  
CENTERED ON DAY 8, AND 30% OF TODAY'S 0Z CANADIAN ENSEMBLE MEAN CENTERED ON DAY  
8  
 
 
FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: MUCH ABOVE AVERAGE, 5 OUT OF 5,  
DUE TO GOOD MODEL AGREEMENT AND CONSISTENCY ON A HIGHLY AMPLIFIED 500-HPA FLOW  
PATTERN ACROSS NORTH AMERICA AND VICINITY.  
 
8-14 DAY OUTLOOK FOR DEC 13 - 19 2025  
 
THE UNUSUALLY HIGH AMPLITUDE 500-HPA FLOW PATTERN IS FORECAST TO PERSIST INTO  
THE FIRST HALF OF WEEK-2 WITH UNCERTAINTY INCREASING SIGNIFICANTLY THEREAFTER.  
THE PERIOD STARTS OFF WITH CONTINUED STRONG RIDGING ACROSS THE BERING SEA AND  
THE WESTERN CONUS. STRONG TROUGHING IS FORECAST ACROSS THE EASTERN CONUS AND  
ENHANCED PACIFIC FLOW IS FORECAST TO CONTINUE ACROSS THE NORTHWESTERN CONUS. AS  
WE ENTER THE SECOND HALF OF WEEK-2, THE FLOW PATTERN BECOMES MORE MURKY. THE 0Z  
ECMWF ENSEMBLE MEAN DEVELOPS A STRONG TROUGH OVER THE CENTRAL PLAINS LATER IN  
WEEK-2 WHILE THE GEFS PREDICTS A MORE ZONAL PATTERN. MEANWHILE THE 0Z CANADIAN  
ENSEMBLE MEAN PERSISTS THE WESTERN RIDGE AND EASTERN TROUGH THROUGHOUT THE  
ENTIRE PERIOD. DUE TO THE UNCERTAINTIES PRESENT DURING THE LATTER HALF OF WEEK  
TWO, THE MEAN 500-HPA PATTERN FOR THE SEVEN DAY PERIOD IS VERY REPRESENTATIVE  
OF THE PREDICTED PATTERN DURING THE FIRST HALF OF THE PERIOD, WHERE MODELS ARE  
IN BETTER AGREEMENT. THIS MEAN 500-HPA PATTERN IS VERY SIMILAR TO YESTERDAY,  
WITH ANOMALOUS RIDGING OVER THE BERING SEA AND WESTERN CONUS AND TROUGHING OVER  
THE NORTHEASTERN CONUS AND SOUTHEAST ALASKA. AS WAS THE CASE WITH THE 6 TO 10  
DAY MEAN, TODAY'S WEEK-2 500-HPA MEAN IS SLIGHTLY MORE AMPLIFIED WITH THE  
OVERALL FEATURES RELATIVE TO YESTERDAY. THIS REFLECTS THE POTENTIAL FOR A VERY  
AMPLIFIED PATTERN DURING THE FIRST HALF OF THE PERIOD. GENERALLY NEAR NORMAL  
MEAN HEIGHTS ARE FORECAST FOR HAWAII, AS BROAD TROUGHING TO ITS NORTH  
RETROGRADES WESTWARD AND FURTHER AWAY FROM THE STATE.  
 
BELOW NORMAL TEMPERATURES ARE FAVORED FOR THE NORTHEASTERN QUADRANT OF THE  
CONUS AS WELL AS ADJACENT AREAS OF THE SOUTHEAST AND NORTHERN PLAINS.  
PROBABILITIES OF BELOW NORMAL TEMPERATURES EXCEED 70 PERCENT ACROSS THE  
NORTHEAST AS WELL AS MUCH OF THE GREAT LAKES REGION. THIS REPRESENTS AN  
INCREASE IN CONFIDENCE RELATIVE TO YESTERDAY AS TODAY'S MODEL SOLUTIONS DEPICT  
SLIGHTLY STRONGER NEGATIVE HEIGHT DEPARTURES IN THE MEAN 500-HPA FIELD.  
CONVERSELY, ABOVE NORMAL TEMPERATURES ARE FAVORED FOR THE SOUTHWESTERN,  
NORTHWESTERN, AND SOUTH-CENTRAL CONUS DUE TO PREDICTED EXPANSIVE RIDGING.  
PROBABILITIES OF ABOVE NORMAL TEMPERATURES EXCEED 80 PERCENT ACROSS MUCH OF THE  
SOUTHWEST AND GREAT BASIN. THIS REPRESENTS AN INCREASE IN COVERAGE RELATIVE TO  
YESTERDAY AS MODEL SOLUTIONS HAVE TRENDED STRONGER WITH THE RIDGE ACROSS THE  
WEST. BELOW NORMAL TEMPERATURES REMAIN FAVORED FOR MUCH OF ALASKA WITH THE  
GREATEST CONFIDENCE (MORE THAN 80 PERCENT) PREDICTED ACROSS PARTS OF SOUTHEAST  
ALASKA. ENHANCED NORTHERLY FLOW AND BELOW NORMAL 500-HPA HEIGHTS ARE EXPECTED  
TO CONTINUE WELL INTO WEEK-2 ACROSS THIS REGION. ABOVE NORMAL TEMPERATURES ARE  
FAVORED FOR HAWAII, CONSISTENT WITH DYNAMICAL MODEL OUTPUT AND WITH ABOVE  
NORMAL SSTS IN THE ADJACENT PACIFIC.  
 
ENHANCED PACIFIC FLOW IS EXPECTED TO PERSIST ACROSS THE NORTHWESTERN CONUS WELL  
INTO WEEK-2. AS A RESULT, ABOVE NORMAL PRECIPITATION IS FAVORED FOR THE PACIFIC  
NORTHWEST, NORTHERN ROCKIES, NORTHERN PLAINS, AND NORTHERN CALIFORNIA. THE  
SOUTHERN EXTENT OF THIS REGION OF FAVORED ABOVE NORMAL PRECIPITATION HAS  
RETREATED NORTHWARD RELATIVE TO YESTERDAY, REFLECTING THE TREND TOWARD A  
STRONGER RIDGE ACROSS THE WESTERN CONUS. CORRESPONDINGLY, INCREASED CONFIDENCE  
FOR BELOW NORMAL PRECIPITATION (GREATER THAN 50 PERCENT) IS INDICATED FOR THE  
SOUTHWEST, CLOSER TO THE CENTER OF THE PREDICTED RIDGE. THIS RIDGE IS PREDICTED  
TO EXPAND EASTWARD DURING THE EARLY TO MIDDLE PART OF THE PERIOD, RESULTING IN  
INCREASED CONFIDENCE FOR DRYNESS EASTWARD ACROSS MUCH OF THE CENTRAL AND  
SOUTHERN PLAINS AND LOWER MISSISSIPPI VALLEY. PREDICTED SURFACE HIGH PRESSURE,  
PARTICULARLY EARLY IN THE PERIOD, FAVORS BELOW NORMAL PRECIPITATION ACROSS MOST  
OF THE EASTERN SEABOARD. ENHANCED LAKE EFFECT SNOW IS STILL POSSIBLE,  
ESPECIALLY DURING THE EARLY PORTION OF WEEK-2, LEADING TO A TILT TOWARD ABOVE  
NORMAL PRECIPITATION FOR MOST AREAS ADJACENT TO THE GREAT LAKES. A TILT TOWARD  
ABOVE NORMAL PRECIPITATION PERSISTS FOR SOUTHERN FLORIDA AND SOUTHERN TEXAS  
NEAR THE SOUTHERN PERIPHERY OF THE BROAD TROUGH FORECAST OVER EASTERN NORTH  
AMERICA. CONVERSELY, A DRY PATTERN IS FAVORED FOR MUCH OF ALASKA, UNDERNEATH  
MEAN OFFSHORE FLOW AHEAD OF THE PREDICTED BERING SEA RIDGE. ABOVE NORMAL  
PRECIPITATION IS FAVORED FOR HAWAII NEAR THE SOUTHEASTERN FRINGE OF PREDICTED  
BROAD CYCLONIC FLOW OVER THE PACIFIC AND CONSISTENT WITH DYNAMICAL MODEL  
GUIDANCE.  
 
THE OFFICIAL 8-14 DAY 500-HPA HEIGHT BLEND CONSISTS OF: 30% OF TODAY'S 6Z GFS  
ENSEMBLE MEAN CENTERED ON DAY 11, 40% 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: AVERAGE, 3 OUT OF 5, DUE TO GOOD  
MODEL AGREEMENT ON AN AMPLIFIED 500-HPA PATTERN DURING THE FIRST HALF OF WEEK-2  
OFFSET BY A SIGNIFICANT INCREASE IN MODEL UNCERTAINTY THEREAFTER.  
 
FORECASTER: SCOTT H  
 
NOTES:  
 
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 (GRAY, "N") NORMAL.  
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 (GRAY, "N")  
NORMAL. 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 1991-2020 BASE PERIOD MEANS AS  
REFERENCE IN THE CLIMATE OUTLOOKS.  
 
THE NEXT SET OF LONG-LEAD MONTHLY AND SEASONAL OUTLOOKS WILL BE RELEASED ON  
DECEMBER 18.  
 
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:  
20081206 - 19911203 - 20131211 - 20041219 - 19981218  
 
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:  
20081206 - 19911202 - 20131211 - 20001207 - 20221120  
 
6-10 DAY OUTLOOK TABLE  
OUTLOOK FOR DEC 11 - 15 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A B  
SRN CALIF A B IDAHO A A NEVADA A B  
W MONTANA A A E MONTANA N A WYOMING A A  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B A S DAKOTA B A  
NEBRASKA A B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A B W TEXAS A B  
MINNESOTA B A IOWA B N MISSOURI B B  
ARKANSAS N B LOUISIANA N B WISCONSIN B N  
ILLINOIS B B MISSISSIPPI B B MICHIGAN B A  
INDIANA B N OHIO B N KENTUCKY B B  
TENNESSEE B B ALABAMA B B NEW YORK B N  
VERMONT B N NEW HAMP B N MAINE B N  
MASS B B CONN B B RHODE IS B B  
PENN B B NEW JERSEY B B W VIRGINIA B B  
MARYLAND B B DELAWARE B B VIRGINIA B B  
N CAROLINA B B S CAROLINA B B GEORGIA B B  
FL PNHDL B B FL PENIN N N AK N SLOPE N N  
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B B  
AK S INT B B AK SO COAST B B AK PNHDL B B  
 
 
 
8-14 DAY OUTLOOK TABLE  
OUTLOOK FOR DEC 13 - 19 2025  
 
STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN  
WASHINGTON A A OREGON A A NRN CALIF A A  
SRN CALIF A B IDAHO A A NEVADA A N  
W MONTANA A A E MONTANA N A WYOMING A N  
UTAH A B ARIZONA A B COLORADO A B  
NEW MEXICO A B N DAKOTA B A S DAKOTA B N  
NEBRASKA N B KANSAS A B OKLAHOMA A B  
N TEXAS A B S TEXAS A N W TEXAS A B  
MINNESOTA B A IOWA B N MISSOURI B B  
ARKANSAS N B LOUISIANA A B WISCONSIN B A  
ILLINOIS B N MISSISSIPPI N B MICHIGAN B A  
INDIANA B N OHIO B N KENTUCKY B B  
TENNESSEE B B ALABAMA N B NEW YORK B N  
VERMONT B B NEW HAMP B B MAINE B N  
MASS B B CONN B B RHODE IS B B  
PENN B N NEW JERSEY B B W VIRGINIA B N  
MARYLAND B B DELAWARE B B VIRGINIA B B  
N CAROLINA B B S CAROLINA B B GEORGIA B B  
FL PNHDL N B FL PENIN N A AK N SLOPE N N  
AK ALEUTIAN B B AK WESTERN B B AK INT BSN B N  
AK S INT B B AK SO COAST B B AK PNHDL B B  
 
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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