NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION. Privacy and Cookie policy

FXUS62 KGSP 071920 AFDGSP

Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 220 PM EST Thu Dec 7 2023

SYNOPSIS
Dry high pressure will continue through Friday then moving off the Carolina coast Friday night with warmer temperatures through the early weekend. Expect rain ahead of an approaching cold front from Saturday through Sunday with thunderstorms more likely on Sunday. As the rain ends Sunday night with colder air behind the front expect some light snow in the North Carolina Mountains.

NEAR TERM /THROUGH FRIDAY/
As of 140 pm EST Thursday: Heights will rise across the East Coast through the period, as a short wave ridge progresses across the region...downstream of a trough deepening across the West. This will allow return flow to begin setting up, as surface high pressure settles off the southeast coast. Skies will remain clear through at least the evening, before cirrus begins streaming into the region from the southwest. The combination of increasing high clouds along with the potential for the boundary layer to remain lightly mixed will create less-than-ideal radiational cooling conditions, and a somewhat problematic min temp forecast. This will probably be a night in which min temps are a bit all over the place...depending on what locations decouple vs. those that maintain a light wind. SW flow and warm advection continues through Friday, with temps expected to warm to above-normal levels despite the continued presence of high clouds.

SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/
As of 115 PM EST Thursday...The upper pattern transitions from a ridge axis to increasing difl flow Sat. This will displace a sfc high off the Atl coast and allow for good moist adv off the Atl and the GOM by the afternoon. Expect enough moisture transport combining with mech lift to produce periods of rain showers across the sw/rn NC mtns and NE GA aft daybreak with little convec potential due the early timing and relatively cool sfc temps.

By Sat night, the atmos become quite dynamic to the west as an acute h5 trof develops across the MS Valley and initiates a stg wavy sfc front over middle TN. This front will be the main weather-maker Sun as it will be supported with high shear thru a deep layer and increasing upper divergence due to coupled jets crossing the area. A pre-frontal trof pushes into the NC mtns arnd 18z (good model consensus on timing) and the overall synoptic forcing will be high enuf to likely produce QLCS even with relatively low instability to work with.

The models continue to indicate arnd 100-250 J/kg of sbCAPE by mid- afternoon ahead of the sfc convg zone, thus a high-shear low-CAPE setup looks to be in store. Expect semi-organized lines of convect capable of producing bowing segments and possible broken-S tors in addition to stg/svr mixed-down straight line winds. The SPC has yet to include an outlook as the event is still Day 4, but the new Day 3 outlook shud have the fcst area in some sort of severe risk. Another issue will be high rainfall amts as the the alignment of strong and deeper cells may linger or train over the same areas while producing high rainfall rates. All in all, this is looking like an event to keep an eye on. Some storm variables will change as we near the event, but right now confidence is abv normal for a sigfnt event to take place.

During the overnight Sun, wrap around moisture will continue and as a colder cP airmass mixes in from the northwest. Expect the development of NW flow snow showers across the wrn NC mtns arnd 00z continuing toward daybreak Mon producing arnd 1-2 inches of accum across the higher elevations. A winter weather advisory may be needed. Highs on Sat will remain abt 5 degrees abv normal and similar highs Sun, except the mtns will see a non-diurnal drop off during the early afternoon behind the sfc front. Abv normal lows Sat night with all the cloudiness and s/ly flow, then a drop-off to the m20s mtn valleys and near freezing over the non/mtns Sun night post FROPA.

LONG TERM /MONDAY THROUGH THURSDAY/
As of 155 PM EST Thursday...A modified cP airmass continues to build across the area Mon and any lingering snow showers across the NC mtns will quickly come to an end due to llvl dry air advection and the orthogonal flow becoming disrupted. The pattern returns quiet over the extended, however, the NC mtn ridges could see black ice issues due to snowfall melting during the day Mon. Surface high pressure is reinforced by a very strong 1040 mb Canadian high diving south on Mon. Good insolation will be had each day, but with this colder airmass slow to modify, max temps will remain generally in the 50s and lows fall into the 20s and 30s each night. Wind chills should not be an issue, even across the higher terrain, as mixed- layered winds remain low end.

AVIATION /19Z THURSDAY THROUGH TUESDAY/
At KCLT and elsewhere: VFR/mostly SKC conditions will continue through the period, with only increasing high clouds expected overnight into Friday. Winds will generally be SW at 5-10 kts during the daylight hours, and 5 kts or less at night.

Outlook: VFR should prevail through Friday night. Moisture will return from the SW late Friday night, and a ceiling restriction could develop as early as daybreak Saturday. Additional restrictions and precip will move in Saturday night ahead of an approaching cold front, which low pressure passing NW of the region will push through on Sunday. VFR conditions return for Monday into Tuesday.

GSP WATCHES/WARNINGS/ADVISORIES
GA...Increased Fire Danger until 5 PM EST this afternoon for GAZ010.
NC...None.
SC...None.

toggle option: (graph/table)

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Greer, SC,