####018014683#### FXUS06 KWBC 101936 PMDMRD Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks NWS Climate Prediction Center College Park, MD 300 PM EDT Fri May 10 2024 6-10 DAY OUTLOOK FOR MAY 16 - 20 2024 Models are in poor agreement today, and are not in good agreement with their own solutions from yesterday. As a result, the official forecast is made with considerable uncertainty, which is not too uncommon during spring. Today, the ECMWF and Canadian ensemble means resemble the GEFS mean from yesterday, with relatively low 500-hPa heights across the northern tier of the CONUS, and in most of the eastern CONUS. The main differences between these two models are found along the southern and eastern tiers of the CONUS, where the Canadian shows lower 500-hPa heights. Meanwhile, the GEFS mean is now much more amplified, with a strong mid-level ridge in the western CONUS and a downstream trough digging into the East. At this time, the Canadian ensemble mean is favored slightly more than the others for two reasons: First, its solution has the lowest amplitude, which is more consistent with both its own solution and the favored circulation pattern from yesterday; second, its mid-level pattern across the western half of the Northern Hemisphere agrees slightly better with historic teleconnections than the other two ensemble means. But the solutions of the other ensemble means are not discounted, particularly since the GEFS mean for 0z, 6z, and 12z have maintained the alternative, highly-amplified solution. Other features in the manual 500-hPa height blend are a strong anomalous mid-level ridge south of eastern Siberia with positive 500-hPa heights extending eastward into the Pacific Northwest, and another mid-level ridge over north-central Canada. Meanwhile, near- to slightly below-normal 500-hPa heights extend from Mainland Alaska southeast into central North America. In the Tropical Pacific, Below-normal 500-hPa heights cover Hawaii, with a weak mid-level trough to the west of the state. While the uncertainties in the mid-level pattern generally result in a low-confidence forecast, there are some areas where tools derived from the ensembles agree on sensible weather. The raw, bias-corrected, and reforecast temperature output from the GEFS, the European ensemble, and the Canadian ensemble all show enhanced odds for above-normal temperatures in the Great Basin, central Far West, southern Texas, the Florida Peninsula, and the Northeast. Odds for unusual warmth during the 6- to 10-day period range from 50 to 60 percent in these areas. Raw and calibrated temperature tools are in much poorer agreement in the rest of the CONUS, Alaska, and Hawaii. Across a large region encompassing central and western sections of the northern tier of the CONUS and a large part of the central and southeastern CONUS have no tilt of the odds toward unusually high or low temperatures due to significantly conflicting signals in these regions. The preponderance of tools show enhanced odds for colder than average weather maximized in southwestern Mainland Alaska while enhanced odds for warmth are encroaching into the northeastern Mainland, and southerly surface flow across Hawaii should favor above-normal temperatures there. The precipitation pattern is a compromise of the tools, leaning toward those from the Canadian ensemble and, due to the uncertainty, adjusted toward some consistency with the forecast from yesterday. An enhanced, cyclonically-curved mid-level jet along with anomalously moist surface flow from the south is expected over portions of the central Gulf Coast region and adjacent Southeast, resulting in a 50 to 60 percent chance for above-normal precipitation there. Most other areas in the CONUS have marginally increased odds for surplus precipitation. Across the CONUS, dryness is favored slightly only in the Big Bend and much of the Pacific Northwest, where positive 500-hPa height anomalies and anticyclonic mid-level flow are anticipated. Under a 500-hPa trough, odds marginally favor above-normal precipitation across Alaska. Farther south, Hawaii should be experiencing moist southerly surface flow downstream from a mid-level trough, enhancing odds for surplus precipitation there, especially in western parts of the state. The official 6-10 day 500-hPa height blend consists of 18% of Today's 0z GFS Ensemble Mean centered on Day 8, 32% of Today's 0z European Ensemble Mean centered on Day 8, and 50% of Today's 0z Canadian Ensemble Mean centered on Day 8 FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: Below average, 2 out of 5, due to poor model agreement and inconsistency among the derived tools in most locations. 8-14 DAY OUTLOOK FOR MAY 18 - 24 2024 The models remain in poor agreement during week-2, with their mean patterns being reasonable extrapolations of their respective 6-10 day means. The GEFS mean remains highly amplified, with a strong anomalous mid-level ridge extending from the western CONUS northward into Mainland Alaska, with a strong downstream mid-level trough in the eastern CONUS. The deepest 500-hPa height anomaly was -120 dm, centered over the Great Lakes. The Canadian ensemble mean has a similar configuration but is far less amplified. Slight positive 500-hPa height anomalies cover the southern Plains and western North America while a weak mid-level downstream trough is found over the eastern CONUS. The Canadian ensemble mean also centers the negative 500-hPa height anomaly over the Great Lakes, but the maximum anomaly reaches only -40 dm. The ECMWF ensemble mean has mid-level height anomalies similar in magnitude to the Canadian ensemble mean, but with a different configuration: Positive 500-hPa anomalies extend into Alaska from the south, and unusually low mid-level heights are in an east-west orientation covering the northern and central tiers of the CONUS, with 500-hPa heights closer to normal farther south. Similar to the 6-10 day period, the Canadian ensemble mean pattern is slightly favored for its consistency with yesterday and its lower amplitude, but other solutions can’t be ruled out given model inconsistency. Not unexpectedly, the disparate model solutions result in broadly inconsistent guidance among the derived tools. The official forecast used a consensus of the various derived tools, leaning toward Canadian raw and European reforecast output, and consistency with yesterday. The best agreement in the temperature tools is in south Texas and the southern Florida Peninsula, where odds for unusual warmth top 60 percent. Odds for extreme temperatures are much lower elsewhere, with enhanced odds for warmth limited to New England and the southern tier of the CONUS from the Four Corners eastward. In the CONUS, only the Pacific Northwest and adjacent Intermountain West have marginally-enhanced odds for cooler than normal weather, consistent with raw Canadian and reforecast ECMWF ensemble outputs. A preponderance of the array of solutions led to somewhat enhanced odds for subnormal temperatures in southwestern Mainland Alaska, and a marginally-increased likelihood for warmer than normal weather in northeastern Mainland Alaska, and the central and western sections of Hawaii. Precipitation tools based on the ECMWF and Canadian ensembles and the GEFS were in poor agreement, and the official forecast is based on a blend of these tools shaded toward the Canadian ensemble mean and consistency with yesterday. This results in a 40 to 50 percent chance for surplus precipitation in most of the Southeast and adjacent parts of the Lower Mississippi and Lower Ohio Valleys. Marginally-increased chances for above-normal precipitation are identified in the Northeast, eastern Great Lakes, Middle Mississippi Valley, parts of the central Plains and adjacent Rockies, Alaska outside the southern tier, and western Hawaii. Meanwhile, odds lean toward dryness in portions of the southern Plains and on the Big Island of Hawaii. The official 8-14 day 500-hPa height blend consists of: 20% of Today's 6z GFS Ensemble Mean centered on Day 11, 20% of Today's 0z European Ensemble Mean centered on Day 11, and 60% of Today's 0z Canadian Ensemble Mean centered on Day 11 FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Much below average, 1 out of 5, due to model disagreement, conflicting tool signals, and a lack of significant indications to favor any specific set of guidance. FORECASTER: Rich Tinker 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 May 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: 19750427 - 19980508 - 19760425 - 19850514 - 19710505 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: 19750428 - 19980507 - 19520518 - 19850514 - 19760424 6-10 DAY OUTLOOK TABLE Outlook for May 16 - 20 2024 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N B OREGON A B NRN CALIF A A SRN CALIF A A IDAHO A N NEVADA A N W MONTANA A N E MONTANA N A WYOMING A N UTAH A N ARIZONA A A COLORADO A A NEW MEXICO A N N DAKOTA N A S DAKOTA N A NEBRASKA N A KANSAS N A OKLAHOMA N A N TEXAS N A S TEXAS A A W TEXAS N N MINNESOTA N A IOWA N A MISSOURI N A ARKANSAS N A LOUISIANA A A WISCONSIN A A ILLINOIS A A MISSISSIPPI N A MICHIGAN A A INDIANA A A OHIO A A KENTUCKY A A TENNESSEE A A ALABAMA N A NEW YORK A A VERMONT A A NEW HAMP A A MAINE A A MASS A A CONN A A RHODE IS A A PENN A A NEW JERSEY A A W VIRGINIA A A MARYLAND A A DELAWARE A A VIRGINIA A A N CAROLINA A A S CAROLINA A A GEORGIA N A FL PNHDL A A FL PENIN A A AK N SLOPE A A AK ALEUTIAN B N AK WESTERN B A AK INT BSN N A AK S INT B A AK SO COAST B A AK PNHDL N N 8-14 DAY OUTLOOK TABLE Outlook for May 18 - 24 2024 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON B N OREGON B N NRN CALIF N N SRN CALIF N N IDAHO N N NEVADA N N W MONTANA B N E MONTANA N N WYOMING N N UTAH N N ARIZONA N N COLORADO A N NEW MEXICO A N N DAKOTA N N S DAKOTA N N NEBRASKA N A KANSAS N N OKLAHOMA A N N TEXAS A N S TEXAS A B W TEXAS A B MINNESOTA N N IOWA N N MISSOURI N A ARKANSAS A A LOUISIANA A A WISCONSIN N N ILLINOIS N A MISSISSIPPI A A MICHIGAN N A INDIANA N A OHIO N A KENTUCKY N A TENNESSEE N A ALABAMA A A NEW YORK N A VERMONT A A NEW HAMP A A MAINE A A MASS A A CONN N A RHODE IS A A PENN N A NEW JERSEY N A W VIRGINIA N A MARYLAND N A DELAWARE N A VIRGINIA N A 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 N AK WESTERN B A AK INT BSN N A AK S INT N N AK SO COAST N N AK PNHDL N 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. $$ ####018001864#### FXUS23 KWNC 101936 PMDSST Tropical Pacific mean sea surface temperature/SST/ outlook NWS Climate Prediction Center College Park MD 300 PM EDT FRI MAY 10 2024 Mean temperature anomaly SST outlooks are in tenth of a degree Celsius for the Nino 3.4 area of the tropical Pacific /5N-5S 120W-170W/. Anomalies are from 1991-2020 Nino 3.4 climatology SST /CLIM/. Three month outlook periods eg. JFM is January through March - FMA for FEB. through APR. See notes below on types of outlooks TYPE JJA JAS ASO SON OND NDJ DJF JFM FMA MAM AMJ MJJ JJA CONS -0.4 -0.6 -0.9 -1.0 -1.1 -1.1 -1.0 -0.8 -0.6 -0.4 -0.1 0.1 0.1 U68 0.0 -0.1 -0.3 -0.3 -0.2 -0.2 -0.0 -0.0 0.1 0.2 0.4 0.6 0.7 L68 -0.8 -1.1 -1.5 -1.8 -1.9 -2.0 -1.9 -1.6 -1.3 -0.9 -0.6 -0.5 -0.6 U95 0.3 0.2 0.2 0.2 0.3 0.3 0.6 0.5 0.5 0.6 0.7 0.9 1.1 L95 -1.0 -1.5 -1.9 -2.2 -2.4 -2.5 -2.5 -2.1 -1.7 -1.3 -0.9 -0.8 -1.0 CCA -0.4 -0.6 -0.7 -0.7 -0.7 -0.7 -0.7 -0.6 -0.5 -0.4 -0.4 -0.4 -0.5 CA -0.4 -0.7 -0.9 -1.0 -1.1 -1.1 -1.0 -0.8 -0.5 -0.3 -0.1 -0.0 -0.0 CFS -0.6 -0.9 -1.2 -1.5 -1.6 -1.5 CLM 27.3 27.0 26.8 26.7 26.7 26.6 26.7 26.9 27.3 27.7 27.8 27.7 27.3 CONS - Official consolidated outlook U68 - The upper limit of the 68 percent confidence interval forecast L68 - The lower limit of the 68 percent confidence interval forecast U95 - The upper limit of the 95 percent confidence interval forecast L95 - THE lower limit of the 95 percent confidence interval forecast CCA - Canonical correlation analysis outlook CA - Constructed analog outlook CFS - NCEP CFS version 2 dynamic model outlook CLM - Climatological mean Nino 3.4 SST This product is available in a graphical format on the internet http://www.cpc.ncep.noaa.gov $$