Sugar Mountain

Forecast Discussion

Summary

SYNOPSIS

... Low pressure will gradually lift north and then east of the area tonight and tomorrow. As it does, drier air associated with broad high pressure will spread over the region and linger through midweek. Another low pressure system is expected to impact the Southeast towards the end of next week.

NEAR TERM /THROUGH SUNDAY/... As of 440pm EST Friday:

Minor change to going forecast to trend remaining POPs down as radar only shows some widely scattered light showers or drizzle, which will continue to fade out into the evening.

With isolated to scattered showers, plenty of cloud cover, and an insitu wedge in place allowing for chilly temperatures, it's been a fairly dreary morning and early afternoon across the FA. Aside from lingering isolated light showers, overall rain coverage has tapered off across the area attm as a front associated with the sfc low pressure nears the GA/SC border and another front curls northeastward into the eastern Carolinas. Given decreased rainfall amounts and additional melting of snow, the Flood Watch has been cancelled with this forecast package, though waters may continue to rise slightly across portions of the FA.

In addition to decreasing rainfall, signs of a weakening insitu wedge continue as well, as winds are shifting across portions of the Upstate from NE to SW, with temperatures warming into the low to mid 50s across the southern portions of the FA. Though the infiltration of some drier air continues to create pockets within the widespread low cloud deck across the Southeast, latest satellite imagery highlights nicely the circulation associated upper low over TN/KY this afternoon. Per latest guidance, expect this feature to move ENE from TN/KY to NC/VA through tonight. Providing additional forcing along with wrap around moisture could allow for an increase in rain chances again across the mountains beginning tonight. Would not entirely rule out a rain/snow mix late overnight into early Sunday morning, especially across the higher terrain as temperatures drop to or just below freezing. Though, little to no snow accumulation is expected. Outside of the mountains, expect conditions to remain dry, yet cloudy given with the infiltration of CAA behind the slowly exiting system and the wedge, which is not expected to fully dissipate tonight. Given saturated soils and residual wedge in place, areas of fog are possible overnight, mainly north of the I-85 corridor.

On Sunday, showers may linger across the TN/NC border, but elsewhere, dry conditions will prevail as drier air infiltrates in. Expect cloud cover to decrease across portions of the Upstate and NW Piedmont, where high temperatures on Sunday will be the warmest, in the mid to upper 50s. Across the mountains, expect temperatures to remain cooler in the 40s.

SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/... As of 115 PM EST Saturday: Lingering showers will persist across the nrn NC mtns to begin the period which will likely transition to a ra/sn mix before daybreak with no snow accum. The overall synoptic pattern will begin to change Mon with a developing h5 ridge to the west and a broad hipres beginning to build into the fcst area. This will make for mostly clear skies Mon and max temps shud have no problem reaching the lower to mid 60s outside the mtns as llvl thicknesses remain relatively high. There will be a transiting upper trof with some measure of a cP airmass mix during the afternoon...however the degree of insol and downsloping will keep temps quite mild. On Tue...the sfc high will establish itself across the Carolinas and mid/Atl which will advect lower theta/e air within n/ly flow. So...maxes will drop a bit...yet likely remaining right arnd normal or just above over most locales. Lows each night will drop below normal by a few degrees as good rad cooling conds set up in a dry column.

LONG TERM /WEDNESDAY THROUGH SATURDAY/... As of 215 PM EST Saturday: Upper-level flat ridging will persist into Wed as sfc hipres weakens and moves off the Al coast. This will make for a dry day Wed with seasonal temps. The atmos remains progressive Thu thru the period as phasing btw nrn and srn stream ulvl jet cores develop a deep latitude trof and swing it across the FA thru Fri night. There is better confidence in the overall pattern as the GFS has come in line with the other op model solns...however the GFS upper low center still remains north of the other guidance. This difference wont make much difference in the sensible wx fcst however.

With the development of a broad Miller-B type sfc low Thu...the flow over the FA will remain quite warm which is evident in the evolution partial thicknesses. There could be some mixed ra/sn early Thu associated with a weak insitu wedge across the nrn zones...but it wont be cold long enuf to expect sigfnt accum. A rainy day is on tap thru Thu as the sfc low occludes and takes it/s time pulling north into Fri. Total precip amts don/t look too threatening for now...but there may some low-end hydro events depending on the actual longevity and degree of moisture transport to the system. As the upper trof swings over the area Fri night...the mtns will likely change over to all snow with low-end accums likely. Max temps will remain seasonal. Min temps will be held a little abv normal as the atmos remains moist through a deep layer.