textproduct: Columbia

WHAT HAS CHANGED

Morning fog along area rivers will be dense in spots. Aviation discussion updated for the 12z TAF issuance.

KEY MESSAGES

- 1. Dry conditions and warmer temperatures continue through midweek before a strong system brings much cooler temperatures this weekend.

DISCUSSION

Key Message 1: Dry conditions and warmer temperatures continue through midweek before a strong system brings much cooler temperatures this weekend.

Some morning fog along area rivers will be dense in spots this morning. Otherwise, heights will begin to rise as a ridge of dry high pressure remains over the area this week. High temperatures will steadily rebound to slightly above normal levels, reaching the mid to upper 70s through Wednesday. Large diurnal temperature swings are expected, with effective radiational cooling allowing overnight lows to drop into the 40s.

Attention will then turn to a complex, deep upper-level trough/low expected to dig across the eastern US late this week, ushering in a much cooler air mass. While global models continue to show some disagreement regarding the system's intensity and placement, there is good agreement that a strong front will push across the east coast by Friday. The associated surface low is expected to intensify as it moves off the Mid-Atlantic coast, bringing increased precipitation chances to the region Thursday into Friday. However, rainfall accumulations are expected to remain light, with only around 20% of LREF members indicating 24-hour QPF greater than 0.10 inches. Strong cold air advection and persistent northwest flow behind the front will usher in cooler and breezy conditions into the weekend, with a taste of winter- like temperatures possible. Temps are currently forecast to run around 5 to 10 degrees below normal. Overnight lows in the mid-30s are becoming increasingly likely, with up to 40 to 70% of LREF members showing temperatures dropping below 35 degrees by Saturday tonight. While breezy conditions and relatively dry air may limit frost potential, temperatures will likely be cold enough to warrant attention both Saturday and Sunday mornings. This will be something to monitor closely as we progress through the week.

AVIATION /12Z MONDAY THROUGH FRIDAY/

Morning MIFG followed by VFR conditions through the period.

Some morning fog is developing along area rivers, with some impacts seen at AGS. Tempos included for this through 13z and will monitor if observation is augmented. Otherwise, light winds and clear skies expected today and tonight. Winds will be generally less than 5 knots today, again variable in direction with high pressure overhead. Some additional morning fog possible on Tuesday, but confidence is low at this time in intensity.

EXTENDED AVIATION OUTLOOK...Dry air will likely prevent widespread restrictions through the extended with moisture increasing Thursday.

CAE WATCHES/WARNINGS/ADVISORIES

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