textproduct: Columbia

WHAT HAS CHANGED

Additional rain is moving into the area with latest trends limiting severe and flooding rain threat today. Aviation discussion updated for 18Z TAFs.

KEY MESSAGES

- 1. Rain exits the area this afternoon and evening, with drier air moving in for Friday.

- 2. Wet weather arrives again on Saturday, persisting through early Monday as a cold front takes its sweet time pushing through.

DISCUSSION

Key Message 1: Rain exits the area this afternoon and evening, with drier air moving in for Friday.

Moderate to, at times, heavy rain continues to push through the forecast area late this morning. SPC Mesoanalysis continues to show a surface low to our northwest, with a front draped into central GA. Ahead of this, moisture rich air continues to advect into the area beneath strong 850 hPa moisture transport. With PWs in the 1.7"-1.8" range, the precipitation has been quite efficient and heavy at times. Some thunder remains possible with this activity but it is unlikely to be as widespread as it was last night. The rain is mostly beneficial at this point. Expecting a couple more rounds across much of the area, with the rain probably moving out of the eastern Midlands by 2p or 3p. Skies will likely remain cloudy to an extent, though, as WV imagery shows southwesterly flow allowing persistent high cloudiness to continue streaming atop the area through this evening and overnight tonight.

Key Message 2: Wet weather arrives again on Saturday, persisting through early Monday as a cold front takes its sweet time pushing through.

High clouds will likely continue streaming atop the forecast area on Friday as southwesterly flow continues. A slow moving cutoff low across the southwestern US is forecast to translate eastward over the next several days on the southern side of a deep trough centered across the Great Lakes region. Multiple shortwaves are forecast to precede this cutoff low, with moisture easily recovering ahead of each of these across the southeastern CONUS. The result will likely be multiple rounds of showers and isolated thunderstorms on Saturday/Sunday/Monday. The exact location of the heaviest rainfall is uncertain but LREF and NBM guidance overlap the best probabilities of >0.25" and >0.5" of rainfall across the southern Midlands and the coastal plain. Overall, this event looks like it will pose little threat for hazardous weather, with mainly beneficial rainfall expected across the area again. High pressure is forecast to push in by the middle of next week, with drier weather likely again.

AVIATION /18Z THURSDAY THROUGH TUESDAY/

Conditions will slowly begin to improve later this afternoon as deeper moisture and rainfall pushes off to the east.

Main moisture axis is finally beginning to push off to the east of the majority of the taf locations as winds begin to turn more southwest to westerly just ahead of the approaching cold front. The main front will push through the area later this evening, turning winds towards a more west/northwesterly direction. Some lingering light rainfall, with mvfr conditions, will still be possible over the next few hours, then by 21z taf locations will see the end of the rainfall and both ceilings and visibilities should begin transitioning to primarily vfr conditions. Enough lingering low-level moisture should keep come vfr cumulus through midnight, then mainly just thin cirrus the remainder of the period. Guidance does not indicate any widespread fog formation late tonight, but would not be completely out of the question for brief low stratus or some patchy fog restrictions if winds can go calm enough and skies clear out enough. Not confident enough at this time to include in tafs, but may need to be monitored. EXTENDED AVIATION OUTLOOK...Another system brings a chance for restrictions once again with showers and thunderstorms this weekend.

CAE WATCHES/WARNINGS/ADVISORIES

SC...None. GA...None.