247 FXUS06 KWBC 121902 PMDMRD Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks NWS Climate Prediction Center College Park, MD 300 PM EDT Tue May 12 2026 6-10 DAY OUTLOOK FOR MAY 18 - 22 2026 Ensemble solutions for 500-hPa anomalies from the ECENS, GEFS, and CMCE are in reasonable agreement regarding the synoptic setup over North America at the outset of the extended range forecast period, with amplified ridging over the North Pacific as well as widespread positive height anomalies over the eastern Contiguous U.S. (CONUS). Negative height anomalies are widespread across the higher latitudes with two defined troughs over the Bering Sea and south of Greenland, as well as a weaker trough situated between the ridges over the West and East coasts. Over time model solutions generally retrogress the Pacific ridge and flatten out the Mid-Atlantic ridge, while weak troughing lingers over the southwestern CONUS. Widespread positive height anomalies across the Lower 48 result in above-normal temperatures being favored for much of the CONUS. The highest chances (>70%) are centered over the Mid-Atlantic and Southeast U.S., where mid-level ridging is further supported by southerly flow at the surface on the western edge of the Bermuda high. A secondary maximum is indicated along the West Coast with odds exceeding 50% for much of California. A slight tilt toward below-normal temperatures remains favored along portions of the U.S.-Canadian border, as well as much lower chances of above-normal temperatures southward through the Great Plains where weak troughing favors increased cloudiness and precipitation. Troughing over the Bering Sea tilts the odds towards below-normal temperatures for the southern half of Alaska, while near-normal temperatures are most likely for northern Alaska. Anomalously warm sea surface temperatures in the Central Pacific strongly favor above-normal temperatures for Hawaii. Weak troughing over the country's midsection along with moist return flow around the Bermuda high favors above-normal precipitation for much of the central and eastern CONUS. Odds are highest (>50%) over much of Texas, likely where the above-described interaction will be best-focused. The strong mid-level ridge over the North Pacific is likely to displace the Pacific storm track well north, pushing much of the northwestern CONUS towards below-normal precipitation. Chances are highest (>50%) for Northern California, directly downstream of the ridge axis. The displaced storm track and troughing over the Bering Sea favor above-normal precipitation for most of Alaska, while near-normal precipitation is indicated for the North Slope. Enhanced subtropical convection in the Central Pacific tilts the odds towards above-normal precipitation for Hawaii. The official 6-10 day 500-hPa height blend consists of 33% of Today's 0z GFS Ensemble Mean centered on Day 8, 34% of Today's 0z European Ensemble Mean centered on Day 8, and 33% of Today's 0z Canadian Ensemble Mean centered on Day 8 FORECAST CONFIDENCE FOR THE 6-10 DAY PERIOD: About average, 3 out of 5, with reasonable model agreement on synoptics and coherent signals from forecast tools, offset by a shifting large-scale pattern. 8-14 DAY OUTLOOK FOR MAY 20 - 26 2026 The week-2 manual blend of 500-hPa height anomalies features a similar setup to the 6-10 day period, resulting in similar outlooks for the 8-14 day period. It should be noted that by the beginning of week-2 the various model ensembles begin to diverge quite a bit, with the ECENS in particular showing a very large spread among ensemble members particularly with respect to the placement of the retrogressing ridge over the North Pacific and the evolution of the shortwave trough over the country's midsection. Persistent positive height anomalies over the Lower 48 result in a continued title towards above-normal temperatures for almost the entire CONUS, while weakness in these positive height anomalies over the Northern Rockies pushes portions of the Pacific Northwest towards near-normal temperatures. As noted, model guidance diverges a lot in week-2 lowering forecast confidence. Probabilities remain above 50% for much of the southeastern CONUS, while much of the Southern Plains has rather low odds (<40%) likely due to continued active weather in the region. Southern Alaska tilts towardsbelow normal temperatures while the northern Mainland is indicated for near-normal temperatures, consistent with troughing over the Bering Sea. Above-normal temperatures remain most likely for Hawaii. Model solutions depict widespread precipitation across much of the eastern CONUS for much of week-2, fed by ample moisture from return flow in the wake of the shortwave trough described in the 6-10 day period. Chances remain elevated (>50%) for much of Texas and extending into Arkansas, as indicated by most forecast tools. Below-normal precipitation remains favored for much of the northwestern CONUS as ridging over the North Pacific keeps the storm track north of the Canadian border. This shift once again favors above-normal precipitation for much of Alaska, while near-normal precipitation is most likely for the North Slope. The Hawaii CON and ERF autoblend indicate a slight tilt towards above-normal precipitation for Hawaii. The official 8-14 day 500-hPa height blend consists of: 33% of Today's 0z GFS Ensemble Mean centered on Day 11, 34% of Today's 0z European Ensemble Mean centered on Day 11, and 33% of Today's 0z Canadian Ensemble Mean centered on Day 11 FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Below average, 2 out of 5, with a shifting large-scale pattern and a wide spread among model solutions, offset by reasonable agreement among forecast tools. FORECASTER: Daniel Barandiaran 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 May 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: 19940511 - 20130513 - 20200424 - 20080518 - 19960426 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: 19940510 - 20200423 - 20130513 - 19960427 - 20080518 6-10 DAY OUTLOOK TABLE Outlook for May 18 - 22 2026 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A B OREGON A B NRN CALIF A B SRN CALIF A N IDAHO A B NEVADA A B W MONTANA N B E MONTANA N N WYOMING N N UTAH A N ARIZONA A N COLORADO A N NEW MEXICO A A N DAKOTA B N S DAKOTA N N NEBRASKA A A KANSAS A A OKLAHOMA A A N TEXAS A A S TEXAS A A W TEXAS A A MINNESOTA N A 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 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 A A FL PNHDL A A FL PENIN A A AK N SLOPE N N AK ALEUTIAN B A AK WESTERN B A AK INT BSN N A AK S INT B A AK SO COAST B A AK PNHDL B A 8-14 DAY OUTLOOK TABLE Outlook for May 20 - 26 2026 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON N B OREGON A N NRN CALIF A N SRN CALIF A N IDAHO A N NEVADA A N W MONTANA A N E MONTANA A B WYOMING A N UTAH A N ARIZONA A N COLORADO A A NEW MEXICO A A N DAKOTA A N S DAKOTA A N NEBRASKA A N 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 A ARKANSAS A A LOUISIANA A A WISCONSIN A N 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 A VERMONT A A NEW HAMP A A MAINE A N 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 A A FL PNHDL A A FL PENIN A A AK N SLOPE N N AK ALEUTIAN B A AK WESTERN B A AK INT BSN B A AK S INT B A AK SO COAST B A AK PNHDL B 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. $$