textproduct: Greenville-Spartanburg

WHAT HAS CHANGED

Slight increase for rainfall totals on Sunday east of the mountains.

KEY MESSAGES

1. Dry conditions continue with marginal fire weather issues today ahead of widespread rainfall on Sunday. Minimal hydro impacts from the rain expected due to ongoing drought conditions. 2. Dry with a warming trend next week, perhaps warming to near record levels by Thursday.

DISCUSSION

Key message 1: Dry conditions continue with marginal fire weather issues today ahead of widespread rainfall on Sunday. Minimal hydro impacts from the rain expected due to ongoing drought conditions.

Another day of quiet weather and dry conditions with marginal fire weather concerns. A surface high slides offshore through the day ahead of an area of low pressure out west that is expected to bring widespread rainfall to the area. For today, model guidance keeps a relatively robust column of dry air aloft, but quickly moistens up late this evening. As for any fire weather concerns, surface winds remain light and from the SW, aiding in moisture transport. This should tick up the dewpoints and allow for RH in the 25-30% range. With not as much dry air above the boundary layer and lighter winds, not anticipating deep mixing.

For tonight, the area of low pressure pushes eastward across the TN Valley and lifts into the area on Sunday. Current trends bring slightly higher rainfall amounts (0.5-1.5 inch) east of the mountains with isolated higher amounts along the usual areas of the Escarpment. With the colder air in place, there is a very small chance that a brief mix of snow and rain could occur at the onset in the western NC mountains before turning to all rain. Not expecting any accumulations and the warming temps keep this event as all rain after that. Additionally, with the widespread ongoing drought and very dry vegetation/soil, not anticipating much in the way of hydro impacts. A few of the models also have a small amount (<50j/kg) of sbCAPE in the southern zones of the CWA Sunday morning and into the afternoon. Confidence is very low on the instability coming to fruition, but cannot rule out a brief rumble of thunder or higher rain rates in those southern zones. Rain timing starts with a few scattered showers overnight and then a widespread steady rain spreading from SW to NE after daybreak Sunday. The system should have rain tapering off west to east and be out of the area between 9PM Sunday to 1AM Monday morning. Behind the system, dry air returns and cuts off precipitation chances once again.

Key message 2: Dry with a warming trend next week, perhaps warming to near record levels by Thursday.

As our Sunday rainmaker departs by Monday, the northerly sfc pressure gradient will weaken and in concert with the influx of deep layered dry air, maximum temperatures will be boosted to 8-10 deg F above climo.

Upper heights atop the SE CONUS will rise through midweek as a warming llvl WSWly flow develops. Under broad flat ridging aloft, no pcpn is expected as piedmont maximum temperatures rise into the middle 70s...near the mid February records. It remains to be seen whether developing baroclinic zone can make any inroads into the cwfa on Friday, or perhaps develop enough weak instability to aid in any shower development. But the bigger news to round out the workweek, is we are expecting one more day of near record warmth.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

At KCLT and elsewhere: VFR conditions to start before restrictions come in overnight and into Sunday. A low pressure system brings widespread rain tonight through the end of the TAF period. All terminals start VFR through the evening and into part of the overnight hours. Clouds increase throughout the day and evening as the system approaches, but cigs remain VFR. The first round of -RA is expected between 06z-08z and onward. A PROB30 should suffice until the majority of rain arrives mid morning, spreading west to east. With the rain, expect cigs to drop into the MVFR category and IFR toward the end of the TAF period. Vsby is expected to drop as well into MVFR/IFR. KCLT should see a drop after 16z-18z. Winds today have a few low-end gusts at KCLT/KGSP and should diminish by 00z. Light S/SE overnight and could become VRB. Winds east of the mountains prevail very light but E/NE Sunday.

Outlook: Rain and associated IFR or lower restrictions remain into Sunday night. Restrictions improve Monday as dry conditions return and persist through the first part of the week.

GSP WATCHES/WARNINGS/ADVISORIES

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