Marine Weather and Tide Forecast for Acworth, GA

SHORT TERM
(Today through Friday)
Issued at 415 AM EDT Thu Jun 18 2026

Quite a bit to talk about across the short term this morning. Arthur is officially post-tropical as of last night having only briefly formed tropical characteristics during the day on Wednesday. The remnant low is swirling over far east Texas and LA as of early this morning with strong storms ongoing on the eastern side of the circulation. The overall system is headed to the NE and expected to pick up steam through the morning hours and into the afternoon, pushing towards north and central Georgia by the evening hours.
Numerous hazards are expected over the next 24 hours, including the potential for flash flooding, river flooding, and potential for a few tropical tornadoes. Also, can't rule out seeing some decent non- tropical wind gusts, especially if the core of the storm undergoes some baroclinic deepening as some models continue to indicate (more on that below). Heavy rainfall may continue for some into Friday along a boundary set up by the passing storm with some uncertainty on exactly where that sets up.

As the remnant system moves towards the CWA, models seem to finally be converging on a solution for exactly how the system moves across the area, for better or worse. CAMs have keyed in on the remnant circulation continuing to move to the NE across MS and AL, eventually coming into northern GA by the evening hours. During the afternoon, some day time heating even with cloud cover allows for multiple thunderstorms to form over all of north and central Georgia - these will likely contain most of the severe threat. A line of storms is expected to form across portions of Alabama later in the evening that extends into central Georgia during the late evening to early overnight hours. Simultaneously, the core of the remnant low moves into north Georgia, bringing some heavy rainfall and potential for strong winds that are mixed down from a developing 850 mb jet.
Heavy rain sticks around into the early morning hours for many. An outflow boundary across central Georgia may provide continued focus for storms in that area well into Friday, though the exact positioning of this boundary varies quite a bit by model.

Moving on to discussion of the individual threats, let's start with rain. Heavy rainfall leading to potential flash flooding and river flooding will occur. Model QPF early this morning shows a pretty wide spread across the CWA, with various CAMs targeting different areas with upwards of 4-5" of rain depending on the exact position of the system and the evolution of afternoon and evening storms.
Most areas see at least 2" of rain - even the global ensembles highlight that across nearly all of north Georgia and parts of central Georgia without really capturing the convection. NBM 90th percentile paints 4-5" and has some concerning amounts exceeding 7".
Of concern is the fact that CAMs are not likely outputting enough rain within storms. Warm rain processes are likely to dominate within the subtropical environment, leading to very efficient precipitation rates that may exceed 1-2" an hour. For areas that see multiple rounds of storms or consistent, heavy rainfall, flash flooding and river flooding will be very likely. The Flash Flood Watch has been slightly expanded east, and remains in effect through Saturday morning.

The next threat to discuss is severe. As with any post-tropical system, being within the front right quadrant of the storms motion usually creates a relatively favorable environment for mini- supercells. This will likely be no different, especially given the CAMs outputting numerous discrete storms ahead of the main system over all of north and central Georgia. SRH values aren't through the roof, but aren't anything to dismiss, with CAMs showing around 100 m2/s2. Instability is present as well at 1500-2000 J/kg during the afternoon and evening. This environment will be supportive of some rotation in updrafts, and the stronger storms may be capable of producing a brief tornado. A strengthening 850mb jet into the evening may also be capable of allowing storms to mix stronger winds to the surface, and some severe wind gusts may be possible.

Next is the non-tstorm wind threat. The aforementioned 850mb jet moves in alongside the main core of the system during the late evening to overnight hours. Given the subtropical airmass and advective processes in place, it is unlikely to see much if any nocturnal inversion set up, which would maintain an environment capable of downward mixing of stronger winds aloft. 850mb jet is forecast to be 50-60 kts, and CAMs are showing 30 to upwards of 50 mph wind gusts across much of the CWA Given the heavy rainfall, trees in certain soils may be in a weakened state that allows them to more easily topple. A Wind Advisory is being considered for this threat and may be issued later this morning.

The core of the system is expected to exit the area on Friday morning. As mentioned above in the QPF discussion, there is some uncertainty on lingering rainfall into Friday. Current guidance prefers a solution which leaves us a bit too "worked over" for continued rain on Friday in all but central Georgia, where what is likely an outflow boundary could provide a focus for renewed storm development as moisture continue to try to advect into the area.
Depending on how things play out, it is possible that north Georgia and much of the metro could be rain free on Friday, which would allow for the Flood Watch to expire a bit earlier. But, there is uncertainty, and some CAMs do try to develop some storms again at least in the metro, which is why some PoPs are retained there.
Friday is highly dependent on how things evolve Thursday, so most of this portion of the discussion is low confidence as a result.

LONG TERM
(Friday night through Wednesday)
Issued at 415 AM EDT Thu Jun 18 2026

The tropical moisture axis is expected to continue to shift southward Friday night into Saturday as a cold front pushed into the state from the north. At least low rain chances will continue south of the front into the day on Saturday, while drier conditions are expected for the remainder of the area. The front is expected to stall across central Georgia Saturday, lifting back northward Saturday night into Sunday. Expect shower and storm chances to return to much of the state Sunday into early next week as deeper moisture and an unstable airmass returns to the area and another cold front moves into the region. Temperatures are expected to remain near normal, mid 80s to near 90, through much of the period.

AVIATION
(12Z TAFS)
Issued at 719 AM EDT Thu Jun 18 2026

MVFR cigs in place across metro TAF sites this morning. While some improvement in cigs is possible, expecting most sites to remain MVFR into afternoon and early evening. SHRA and TSRA will progressively increase into the afternoon in coverage and remain into the overnight hours. Winds gusts could be very impactful starting ~00Z for several hours, with gusts up to 30 kts. Cigs are expected to lower again tomorrow morning with IFR/LIFR possible as rainfall comes to an end.

//ATL Confidence
12Z Update
Medium strength of wind gusts. High all others.

Lusk

PRELIMINARY POINT TEMPS/POPS
Athens 87 69 87 66 / 90 100 20 0 Atlanta 84 71 85 68 / 90 90 40 10 Blairsville 80 65 81 58 / 90 90 30 0 Cartersville 85 70 85 64 / 100 90 40 0 Columbus 84 72 85 71 / 90 90 70 30 Gainesville 85 69 85 65 / 90 90 20 0 Macon 86 70 85 69 / 90 100 70 20 Rome 84 70 86 64 / 100 80 30 0 Peachtree City 83 70 84 67 / 90 100 50 10 Vidalia 91 73 86 72 / 70 80 80 10

FFC WATCHES/WARNINGS/ADVISORIES
None.