Extended Forecast Discussion NWS Weather Prediction Center College Park MD 259 AM EDT Mon Aug 1 2022 Valid 12Z Thu Aug 4 2022 - 12Z Mon Aug 8 2022 ***Monsoon remains active across the Southwest and heavy showers and storms are likely from the Ohio Valley to the Northeast for the end of the week*** ...General Overview... An active upper level flow pattern will be in place across the northern tier states, with a well defined trough and cold front crossing the Great Lakes and then New England by the end of the week. Another trough is expected to reach the Northern Rockies by Friday and then traverse the Northern Plains by next weekend. Meanwhile, the core of the upper ridge intensifies across the central Plains for the end of the week and expands in coverage by the weekend, and the monsoonal pattern across the Four Corners region looks to remain active as well. ...Guidance Evaluation/Predictability Assessment... There is now above average forecast confidence for the Thursday-Friday time period as the deterministic model guidance indicates very good synoptic scale agreement. However, by the beginning of next week, the 00Z CMC becomes much stronger with the ridge across the northern Plains and southern Canada, and loses support from the GFS/ECMWF and ensembles. The WPC medium range product suite was primarily derived from a multi-deterministic blend through early Saturday, and then gradually increasing use of the GEFS/ECENS means and the National Blend of Models for QPF. The blending processes tend to mitigate lingering mesoscale system timing and focus variances consistent with individual system predictability. ...Weather/Hazards Highlights... Another brief episode of anomalous heat is expected to make weather headlines for the end of this week across the Mid-Atlantic and Northeast, with daytime highs running well into the 90s from the Carolinas to New England. Meanwhile, maximum temperatures will likely be near to slightly below normal across much of the western U.S. for most of the forecast period. This also includes the Desert Southwest to the Great Basin where increased cloud cover and rainfall will tend to keep temperatures in check. In terms of precipitation, there is a stronger model signal for a corridor of heavy showers and storms ahead of the cold front crossing the Great Lakes and Ohio Valley, and a Slight Risk area on the Day 4 excessive rainfall outlook is in place just north of the Ohio River for Thursday. There will still be plenty of monsoonal moisture in place across the southwestern U.S., with enough expected coverage of slow moving storms to merit a Slight Risk area for both Thursday and Friday across much of eastern Arizona. Scattered to numerous showers and storms are also likely for portions of the Gulf Coast region to close out the week. Hamrick Additional 3-7 Day Hazard information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range 500mb heights, surface systems, weather grids, quantitative precipitation, experimental excessive rainfall outlook, winter weather outlook probabilities and heat indices are at: https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml https://www.wpc.ncep.noaa.gov/#page=ero https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4 https://www.wpc.ncep.noaa.gov/heat_index.shtml