


Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
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617 FXUS06 KWBC 031901 PMDMRD Prognostic Discussion for 6 to 10 and 8 to 14 day outlooks NWS Climate Prediction Center College Park, MD 300 PM EDT Thu July 03 2025 6-10 DAY OUTLOOK FOR JUL 09 - 13 2025 The ECMWF, GEFS and Canadian ensemble models generally agree on the overall 500-hPa height pattern over North America and surrounding regions during the 6-10 day period. The manual height blend is based on 0Z ensemble means, weighing the ECMWF model greater due to recent model skill. The manual blend shows a mid-level trough and below normal heights over Mainland Alaska and the northern Gulf of Alaska. Farther south, a weak trough (in the full height field) is predicted near the Oregon coast. A mid-level ridge and positive 500-hPa height anomalies are forecast across most of the Western Contiguous United States (CONUS) with the 594-dm height contour forecast to envelop much of the southwestern quarter of the Lower 48 states. The ensemble means predict the center of the subtropical high to be centered over Arizona (and briefly southern California) during this period, with a local maximum height of about 597 dm. Despite a weak trough predicted over the Eastern CONUS, positive 500-hPa height anomalies are forecast from the Northern Plains eastward across much of the Great Lakes region and Northeast. This represents the southern extent of broad mid-level anomalous ridging centered over central and southern Canada. For approximately the southeastern quarter of the CONUS, 500-hPa heights are favored to be near normal. Weak positive height anomalies (+30 meters) are depicted for the Hawaiian Islands. Daily uncalibrated 2-meter temperature anomalies from the ensemble means, and the reforecast temperature tools support above normal temperatures over most of the western and eastern thirds of the CONUS. This is consistent with mid-level ridging and positive height anomalies in the West, and widespread southerly surface flow from the Gulf in the East. The southerly flow in the East is due to the clockwise circulation of air around an anticyclone predicted to be centered off the Southeast coast. A very sharp temperature gradient is indicated near the West coast, attributed to unseasonably cold water just off the coast and very warm air a short distance inland. Marine layer intrusions commonly occur with high pressure over the eastern Pacific and low pressure inland over the far western CONUS. Maximum probabilities favoring above normal temperatures (70-80%) are depicted over portions of the Interior West. Below normal temperatures are favored for central and south-central portions of the Great Plains, supported by the ECENS and the CMCE, but not the GEFS. Below normal temperatures are also favored across most of Alaska tied to mid-level troughing and below normal heights. For the Aleutians, the temperature guidance varies widely, and near normal is thought to be the most likely outcome. A compromise between the automated and consolidated temperature tools favors above normal temperatures across all but the Big Island (where near normal temperatures are favored), largely mirroring the sea-surface temperature pattern expected around the Hawaiian Islands. Above normal precipitation is favored for most of Alaska, excluding the far western Mainland, due to persistent surface low pressure forecast over the northwestern Gulf of Alaska and ensuing onshore flow. Above normal precipitation is also favored for most areas east of the Rockies, consistent with the various reforecast precipitation tools and GEFS and ECENS raw precipitation. This is also reasonable given the predicted mid-level trough and expected presence of a near-stationary front, which is roughly collocated with the 40-50% probability enclosure favoring above normal precipitation. The below normal precipitation favored over the Central Great Basin is consistent with a mid-level ridge, positive height anomalies, and enhanced subsidence aloft. With the predicted ridge axis in the vicinity of central or northern Arizona, monsoonal moisture (or perhaps moisture related to a gulf surge originating from tropical activity over the eastern Pacific) may overspread southern Arizona and southwestern New Mexico. A majority of the precipitation guidance supports wetter-than-normal conditions across the Pacific Northwest and northern Intermountain region, downstream of a weak trough forecast near the Northwest coast. Wetter-than-normal conditions are also favored across Hawaii based on the automated precipitation forecast. The official 6-10 day 500-hPa height blend consists of 30% of Today`s 0z 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: Near average, 3 out of 5, with overall good agreement among models on the mean mid-level height pattern, offset by uncertainty related to differences among temperature and precipitation forecast tools. 8-14 DAY OUTLOOK FOR JUL 11 - 17 2025 ECWMF, GEFS and Canadian ensemble mean forecasts for the 500-hPa height pattern over North America during the 8-14 day period remain in overall good agreement. In the manual blend, the predicted trough over Mainland Alaska is forecast to weaken, though below normal 500-hPa heights are still expected to dominate nearly all of the state. Anomalous ridging is depicted across much of southern and especially eastern Canada, with the southernmost extent of this anomalous ridging extending over the northern tier of the U.S. The full field height pattern features a weak trough over the Pacific Northwest, a ridge over most of the remainder of the West, and broad troughing across the East. Associated with the western CONUS ridge are positive height anomalies and a 594-dm height contour enveloping much of the Southwest. Near normal 500-hPa heights are predicted across Hawaii. Below normal temperatures are favored for nearly all of Alaska in the 8-14 day period, under a predicted trough. Below normal temperatures are also favored over central and south-central portions of the Great Plains, and adjacent parts of Missouri, supported by the consolidation tool and the ECENS reforecast temperature tool. Above normal temperature probabilities are elevated for most of the remainder of the CONUS, with maximum probabilities of 50-60% depicted from the central Rockies into the northern Plains and northwestern Minnesota, and also for most of the Gulf Coast and Southeast Coast. The widespread area of favored above normal temperatures is consistent with most of todays temperature guidance. The anomalous warmth indicated across the West is also supported by a mid-level ridge and positive height anomalies, while in the East it is largely supported by low-level southerly flow and weak positive height anomalies at the 500-hPa level. Above normal temperatures are favored across the Hawaiian Islands, consistent with the temperature consolidation and automated temperature tool. The week-2 precipitation outlook is similar to that predicted for the earlier 6-10 day period. Above normal precipitation is favored for most of Alaska (excluding parts of far western Mainland Alaska where near normal precipitation is favored) due to onshore flow associated with surface low pressure over the northwestern Gulf of Alaska. Most models and the consolidation favor enhanced probabilities for above normal precipitation for parts of the Pacific Northwest in week-2. Above normal precipitation is favored from most of the eastern and central CONUS southwestward into southern New Mexico and southern Arizona. Slightly higher odds for above normal precipitation (40-50%) are indicated for the Mid-Atlantic, southern Ohio and Tennessee Valleys. This area coincides approximately with the southern flank of a broad mid-level trough and a predicted near-stationary front that are forecast to enhance precipitation amounts. Above normal precipitation is favored across Hawaii in week-2, consistent with the precipitation consolidation and the Auto blend of precipitation tools. The official 8-14 day 500-hPa height blend consists of: 25% of Today`s 0z GFS Ensemble Mean centered on Day 11, 40% of Today`s 0z European Ensemble Mean centered on Day 11, and 35% of Today`s 0z Canadian Ensemble Mean centered on Day 11 FORECAST CONFIDENCE FOR THE 8-14 DAY PERIOD: Near average, 3 out of 5, due to good overall agreement on the mean mid-level height forecast, offset by weak and conflicting signals especially in the precipitation guidance for many areas. FORECASTER: Anthony A 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 July 17. 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: 20070618 - 20060621 - 20050629 - 19790717 - 20030628 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: 20060624 - 20010702 - 20070618 - 19530620 - 20040612 6-10 DAY OUTLOOK TABLE Outlook for Jul 09 - 13 2025 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A A OREGON A A NRN CALIF A N SRN CALIF A N IDAHO A A NEVADA A B W MONTANA A A E MONTANA A A WYOMING A N UTAH A B ARIZONA A N COLORADO A N NEW MEXICO A N N DAKOTA A A S DAKOTA A A NEBRASKA N A KANSAS B A OKLAHOMA B A N TEXAS A A S TEXAS A N W TEXAS N A MINNESOTA A N IOWA N A MISSOURI N A ARKANSAS A A LOUISIANA A A WISCONSIN N N ILLINOIS N A MISSISSIPPI A A MICHIGAN N 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 N AK N SLOPE B N AK ALEUTIAN B A AK WESTERN B N AK INT BSN B A AK S INT B A AK SO COAST B A AK PNHDL B A 8-14 DAY OUTLOOK TABLE Outlook for Jul 11 - 17 2025 STATE TEMP PCPN STATE TEMP PCPN STATE TEMP PCPN WASHINGTON A A OREGON A A NRN CALIF A N SRN CALIF A N IDAHO A B NEVADA A B W MONTANA A N E MONTANA A N WYOMING A N UTAH A B ARIZONA A N COLORADO A N NEW MEXICO A N N DAKOTA A A S DAKOTA A A NEBRASKA N N KANSAS B A OKLAHOMA B A N TEXAS A A S TEXAS A N W TEXAS B A MINNESOTA A N IOWA N N MISSOURI N A ARKANSAS A A LOUISIANA A N WISCONSIN A N ILLINOIS A A MISSISSIPPI A A MICHIGAN A N 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 N AK N SLOPE B A AK ALEUTIAN B A AK WESTERN B N 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. $$