Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
560 FXUS02 KWBC 160800 PMDEPD Extended Forecast Discussion NWS Weather Prediction Center College Park MD 300 AM EST Sun Nov 16 2025 Valid 12Z Wed Nov 19 2025 - 12Z Sun Nov 23 2025 ...South-central U.S. Heavy Rain/Runoff Threat mid-late week... ...Guidance/Predictability Assessment... The WPC medium range product suite was primarily derived from a composite blend of reasonably well clustered recent guidance of the GFS/ECMWF/Canadian valid for Wednesday/Thursday in a pattern with seemingly above normal predictability and ensemble/machine learning support and good WPC continuity overall. The extent of later week southern stream upper trough/system digging along/off the West Coast becomes more varied in guidance the last few runs uncharacteristically showing the ECMWF on the more progressive side of the full envelope of solutions and the GFS on the less progressive side. The Canadian seems to offer a solution closer to the middle, more in line with the GEFS/ECMWF/Canadian ensemble means and WPC continuity along with the National Blend of Models. ...Weather/Hazards Highlights... Ample upper trough energy and organized precipitation set to dig through the West Coast within an emerging southern stream flow over the next few days will spread across the Great basin/Southwest midweek to include some enhanced mountain snows. Mid-later week downstream system progression and lead moisture and instability return flow genesis into wavy fronts over the south-central to eastern U.S. and meso-scale features should lead to emergence of a growing area of moderate to heavy rains and strong thunderstorms over the south-central U.S., along with eastward progression later week into the weekend. Accordingly, there is a WPC Day 4/Wednesday Excessive Rainfall Outlook Marginal Risk area for the south- central U.S. and a Day 5/Thursday Slight Risk area was introduced there given cumulative heavy convective/repeat rain potential. Another digging east Pacific system may offer some enhanced precipitation chances to the West Coast states Thursday/Friday along with closed low potential offshore and to the Southwest next weekend along with uncertain organized precipitation to monitor. Pre-frontal temperatures will be much warmer than average for much of the south-central/southern U.S. into this period to include some record temperatures upwards to 10-20 degrees above normal. This translates to highs commonly into the 80s, with some warming shifting to the East late week/weekend. Meanwhile, rounds of troughing in California to the West/Southwest will lead to below average highs this week about 5-10+ degrees below climatology. Schichtel 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 forecast (QPF), excessive rainfall outlook (ERO), winter weather outlook (WWO) probabilities, heat indices, and Key Messages can be accessed from: 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 https://www.wpc.ncep.noaa.gov/#page=ovw $$