Prognostic Meteorological Discussion
Issued by NWS
Issued by NWS
356 FXUS01 KWBC 250639 PMDSPD Short Range Forecast Discussion NWS Weather Prediction Center College Park MD 138 AM EST Mon Nov 25 2024 Valid 12Z Mon Nov 25 2024 - 12Z Wed Nov 27 2024 ...Heavy snow over parts of the Sierra Nevada Mountains, Upper Great Lakes and Central Rockies... ...Below average temperatures in the Northern Plains; above average temps in the Southern Plains/Lower Mississippi Valley today... An upper-level trough will swoop into the West Coast from the northeast Pacific early this week. This trough will direct a very anomalous subtropical moisture plume along its base at central and southern California today and Tuesday. A surface low pressure system will help focus the anomalous moisture over coastal areas as well as the Sierra Nevada. Parts of the southern Sierra below about 8000 feet may experience instances of Flash Flooding today. Rock/mud slides and general debris flow are some of the possible impacts from excessive rainfall in mountainous areas. Heavy snow is probable at the higher elevations of the southern Sierra, where 3-4 feet are forecast to accumulate with isolated higher amounts possible by Wednesday morning. The anomalous moisture feed is also expected to penetrate into the interior of the West. Parts of the Great Basin will experience snow showers while heavy snow blankets the Intermountain West and Colorado Rockies with 1-2` (isolated 3`) likely over the next couple of days. Elsewhere, a pair of low pressure systems moving through the Upper Midwest/Great Lakes will generate several inches of snow over the Upper Peninsula of Michigan, while snow showers occur across the greater Upper Midwest and Lower Great Lakes. Temperatures will remain above average for one last day from the Southern Plains into the Midwest before a strong cold front pushes through on Tuesday. Some record high temperatures (in the mid to upper 80s) might be set over south Texas today. Highs topping out in the teens and 20s will represent a negative 20-30 degree departure from normal for parts of the Northern Plains today. Mild conditions continue over much of the East Coast through Tuesday. Kebede Graphics available at https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php $$