Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0350 AM CST Mon Jan 18 2021 Valid 211200Z - 261200Z ...DISCUSSION... ...Thursday/Day 4 and Friday/Day 5... The medium-range models move a shortwave trough across the Desert Southwest on Thursday as zonal mid-level flow remains from the southern Plains to the Eastern Seaboard. Thunderstorm development will be possible on Thursday across parts of the western and central Gulf Coast region along the northern edge of a moist airmass. Instability is expected to be too weak for severe thunderstorm development. The shortwave trough is forecast to move into the Gulf Coast States on Friday. Thunderstorms will again be possible in the northern part of the moist airmass which should be located from the Texas Coastal Plain eastward to the Florida Panhandle. Instability is again forecast to be weak suggesting severe thunderstorm potential will be minimal. ...Saturday/Day 6 to Monday/Day 8... On Saturday, the medium-range models move an upper-level ridge across the Mississippi Valley as southwest mid-level flow becomes established from the Four Corners region eastward into the Great Plains. The models are in reasonable agreement on Sunday moving an upper-level trough across the Intermountain West. Moisture return is forecast to take place ahead of this system in parts of the southern Plains. Thunderstorm development will be possible during the day on Sunday from Texas northward into Oklahoma along an axis of instability. Although a severe threat can not be ruled out, predictability remains low for Sunday. On Monday, the upper-level trough is forecast to move into the Great Plains as a cold front advances into the Arklatex. Thunderstorm development will be possible along and ahead of the front across the lower to mid Mississippi Valley during the day on Monday. If the forecasts verify, a severe threat would be possible in areas that can heat up sufficiently ahead of the front. However, predictability is low this far out in the forecast period.
There’s more click here.