textproduct: Columbia

WHAT HAS CHANGED

Minimal change to Key Messages. Aviation discussion updated for 18z TAFs.

KEY MESSAGES

- 1. Rain clears out today followed by cool temps into mid- week before a warming and wetter pattern develops.

DISCUSSION

Key Message 1: Rain clears out today followed by cool temps into mid-week before a warming and wetter pattern develops into the weekend.

The slow moving front will clear the area this afternoon and along with it, any residual rain chances. Surface ridging than builds into the region Tuesday with PWAT's dropping to around 0.50 inches as this drier surface high pressure builds into the Mid Atlantic. Persistent northeasterly low level flow into the mid week should keep temperatures near to just below normal with dry weather expected. Weak surface ridging is expected to continue into the late week along with some building heights and temps returning to near-above average.

The weekend is looking more active as moisture returns across the region as deep southwesterly develops. There could end up being some tropical connection within this flow with NHC now outlooking the southern gulf with a 70% chance of development. This will be the key component to whether we see appreciable rain with this setup. Without any tropical component, a broad surface ridging will build and allow for widespread but weak overrunning with no notable synoptic forcing (not dissimilar to last weekend...) and therefore a generally low QPF setup. With a tropical- synoptic shortwave to help drive both enhancement of PWAT's and omega, then we could see a notable rain event given the frontal boundary & overrunning favorability in place. Guidance is a mess of solutions at this point and until a steady state surface low develops in the gulf, uncertainty will remain very high.

AVIATION /15Z MONDAY THROUGH FRIDAY/

Periodic MVFR cig restrictions continue into the afternoon before VFR conditions are expected this evening into Tuesday.

Rain has cleared the TAF sites early this afternoon, with some drier air pushing in behind the front from the northeast. Clearing is seen back toward the Upstate and this should continue to work toward the area, bringing an end to lingering ceiling restrictions later this afternoon into the early evening (around 21-00z). Winds should remain light out of the northeast the remainder of the day. Overnight, drier air will continue to stream into the region with partly skies thanks to passing cirrus. Despite the drier air, cannot rule out a few patchy locations with fog (mainly AGS/OGB) near daybreak Tuesday. Confidence in this remains too low to add in the TAF at the moment. VFR conditions then likely continue through the end of the TAF period but northeasterly winds pick up toward 10-12 kts Tuesday morning where isolated gusts nearing 20 kts could be possible.

EXTENDED AVIATION OUTLOOK...VFR conditions are expected into the mid to late week with drier air in place.

CAE WATCHES/WARNINGS/ADVISORIES

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