FXUS06 KWBC 301902 PMDMRD Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks NWS Climate Prediction Center College Park, MD 300 PM EDT Wed October 30 2024 6-10 DAY OUTLOOK FOR NOV 05 - 09 2024 Today's model solutions are in good agreement on the predicted amplified 500-hPa height circulation pattern across North America and surrounding regions during the 6-10 day period. The manual 500-hPa height blend is based primarily on the ensemble means from the GEFS, ECMWF and Canadian models due to recent model skill. The resultant manual blend features a more persistent longwave mid-level trough and negative 500-hPa height anomalies centered over the Aleutians, while ridging and positive 500-hPa height anomalies are predicted over the eastern Gulf of Alaska, Southeast Alaska and parts of the northwestern contiguous U.S. (CONUS). Another mid-level trough with negative mid-level height anomalies are forecast over the southwestern CONUS. Conversely, above-normal mid-level heights and ridging are predicted across the eastern CONUS. Near-normal heights are predicted across Hawaii. Enhanced chances for above-normal temperatures are strongly favored beneath the mid-level ridge across much of the eastern and central U.S. during the 6-10 day period. Chances exceed 80% for above-normal temperatures across most of the eastern CONUS, supported by most of the dynamical temperature forecast tools. Conversely, near- to below-normal temperatures are favored across most of the western CONUS associated with predicted troughing over the region. In Alaska, troughing centered over the Aleutians favors increased southerly flow developing across much of Mainland Alaska leading to elevated odds of near- to above-normal temperatures. High probabilities of above-normal temperatures are forecast across Hawaii, consistent with the GEFS and ECENS reforecast consolidation. The 6-10 day precipitation forecast favors below-normal precipitation for parts of the western CONUS due to the ridging and above-normal 500-hPa heights. Troughing initially over the western CONUS and gradually progressing eastward tilts the odds towards above-normal precipitation over much of the central and eastern CONUS. The highest odds (greater than 50 percent) are over parts of Colorado, New Mexico and Texas due to strong baroclinic forcing and potential for a stationary front to set-up across the region. In Alaska, the synoptic pattern over the Alaska region tends to favor stormier conditions over the Gulf of Alaska and above-normal precipitation. Near-normal precipitation is forecast for Hawaii due to the near-normal 500-hPa heights. The official 6-10 day 500-hPa height blend consists of 35% of Today's 6z GFS Ensemble Mean centered on Day 8, 35% 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: Above-Average, 4 out of 5. Good agreement among the dynamical tools is offset by a more progressive pattern by the end of the period. 8-14 DAY OUTLOOK FOR NOV 07 - 13 2024 Ensemble mean solutions for the 8-14 day period predict a fairly consistent 500-hPa circulation pattern relative to the 6-10 day period across North America and the surrounding regions. The week-2 manual height blend depicts weakly above-normal heights (+30 meters) across much of the eastern half of the CONUS, significantly less than in the 6-10 day period. Positive height anomalies are also forecast across the northwestern and north-central CONUS as more ridging moves over the region representing a quick transition from the prior period. A weak trough is forecast over the Southwest as the mid-level pattern becomes more transient over those areas. Troughing and negative height anomalies are favored to persist across much of Alaska, with near-normal heights forecast for Hawaii. Near- to above-normal temperatures are favored for most of CONUS during week-2 beneath the forecast ridge and above-normal 500-hPa heights across the region with good agreement among the tools. Below-normal temperature is forecast over portions of southern California, Arizona and southwestern New Mexico due to a predicted weak trough over the region. Troughing over Alaska favors increased southwesterly flow over much of the Mainland and Southeast Alaska leading to increased chances for near- to above-normal temperatures. Probabilities for below-normal temperatures are increased across parts of the Aleutians underneath increased northerly flow on the backside of the trough. Hawaii continues to tilt strongly towards above-normal temperatures, consistent with the ECENS and GEFS reforecast consolidation. Odds are slightly elevated for below-normal precipitation over parts of California due to an influence from ridging. Below-normal precipitation is also forecast from parts of the Northern Plains extending eastward to the Great Lakes and the Northeast associated with the below-normal 500-hPa heights. Above-normal precipitation is likely over parts of the northwestern and south-central CONUS as well as portions of the southern Eastern Seaboard, supported by most of the dynamical precipitation forecast tools. Troughing over Alaska favors a persistent stormy pattern across the state, consistent with most of the dynamical precipitation forecast tools. Near-normal precipitation remains favored across Hawaii under near-normal 500-hPa Heights. The official 8-14 day 500-hPa height blend consists of: 35% of Today's 6z GFS Ensemble Mean centered on Day 11, 40% of Today's 0z European Ensemble Mean centered on Day 11, and 25% of Today's 0z Canadian Ensemble Mean centered on Day 11 FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: About-Average, 3 out of 5. due to good model agreement on a persistent 500-hPa flow pattern across North America, offset by deamplification of the 500-hPa height pattern. FORECASTER: Luke H 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 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 November 21. 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: 20051102 - 19941106 - 19851019 - 19881113 - 19941113 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: 20031108 - 19561025 - 20051103 - 20041021 - 19941108 6-10 DAY OUTLOOK TABLE Outlook for Nov 05 - 09 2024 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N B OREGON N B NRN CALIF N B SRN CALIF B B IDAHO N N NEVADA B B W MONTANA N N E MONTANA N N WYOMING N A UTAH B A ARIZONA B A COLORADO B A NEW MEXICO B A N DAKOTA A N S DAKOTA A N NEBRASKA N A KANSAS N A OKLAHOMA N A N TEXAS A A S TEXAS A A W TEXAS B A MINNESOTA A N IOWA A A MISSOURI A A ARKANSAS A A LOUISIANA A A WISCONSIN A A ILLINOIS A A MISSISSIPPI A A MICHIGAN A A INDIANA A A OHIO A A KENTUCKY A A TENNESSEE A A ALABAMA A A NEW YORK A N VERMONT A N NEW HAMP A N MAINE A N MASS A N CONN A N RHODE IS A B PENN A N NEW JERSEY A B W VIRGINIA A A MARYLAND A N DELAWARE A B VIRGINIA A N N CAROLINA A A S CAROLINA A A GEORGIA A A FL PNHDL A A FL PENIN A A AK N SLOPE A A AK ALEUTIAN N A AK WESTERN A A AK INT BSN A A AK S INT A A AK SO COAST A A AK PNHDL A A 8-14 DAY OUTLOOK TABLE Outlook for Nov 07 - 13 2024 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A A OREGON A N NRN CALIF A N SRN CALIF B N IDAHO N N NEVADA N N W MONTANA A N E MONTANA A N WYOMING A N UTAH N A ARIZONA B A COLORADO A A NEW MEXICO N A N DAKOTA A N S DAKOTA A N NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A A S TEXAS A A W TEXAS A A MINNESOTA A N IOWA A N MISSOURI A N ARKANSAS A N LOUISIANA A N WISCONSIN A N ILLINOIS A N MISSISSIPPI A N MICHIGAN A N INDIANA A N OHIO A N KENTUCKY A N TENNESSEE A N ALABAMA A N NEW YORK A N VERMONT A N NEW HAMP A N MAINE A N MASS A N CONN A N RHODE IS A N PENN A N NEW JERSEY A N W VIRGINIA A N MARYLAND A N DELAWARE A N VIRGINIA A N N CAROLINA A A S CAROLINA A A GEORGIA A A FL PNHDL A A FL PENIN A A AK N SLOPE A A AK ALEUTIAN B A AK WESTERN N A AK INT BSN A A AK S INT A A AK SO COAST A 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. $$