Area Forecast Discussion
Issued by NWS Greer, SC
Issued by NWS Greer, SC
835 FXUS62 KGSP 121802 AFDGSP Area Forecast Discussion National Weather Service Greenville-Spartanburg SC 202 PM EDT Sat Jul 12 2025 .SYNOPSIS... Expect scattered thunderstorms and heavy downpours around the region each day of the coming week. A few storms this weekend will pose a risk of damaging wind gusts. The hottest days of the next week look to be Sunday and Monday, with heat index rising over 100 each of those days in most of the Piedmont. && .NEAR TERM /THROUGH SUNDAY/... As of 145 PM EDT Saturday: The situation looks like the classic summertime day across the fcst area. Already seeing numerous showers and storms across the mountains and along the Blue Ridge Escarpment given sfc-based CAPE of 2500-3000 J/kg. Shear remains weak as per usual at this time of year, so any organization of storms that happens will be along outflows and cold pool consolidations. Can`t rule out a few wet microburst producers, mainly north of I-40 where the dCAPE reaches above 800 J/kg, working its way down into the western Piedmont later today. Speaking of which, the expectation is for the convection to come down off the Escarpment and to develop eastward through the afternoon, so the entire fcst area gets at least a chance into the early part of the evening. Temps will remain warm, but not hot enough to worry about reaching Advisory criteria. This evening, the storms should diminish in typical fashion and timing, thereafter we will watch for low stratus and fog development mainly over the mtns. Low temps tonight should be a few degrees above normal. For Sunday, the overall pattern doesn`t change much, so the forecast should be essentially persistent, as a positively-tilted trof axis hangs back over the Midwest to the Ozarks, supporting a weak frontal boundary that remains well to our northwest. Meanwhile, a mid/upper ridge over the Gulf will build a bit over our area. The effect will be lower precipitable water and the reintroduction of some mid-level dry air. Buoyancy/shear will be similar to today, but storms should be less numerous, and what develops should have a slightly better chance at producing strong downdrafts. The lower PW should provide a downward trend to the flood threat. Consistent with the slightly drier air mass and less precip coverage, temps should climb about 3-5 degrees higher for afternoon highs. && .SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/... As of 1145 AM Saturday: The upper ridge axis is progging to linger atop the region to start off the work week, and just like Sunday, another hot afternoon is expected, with Piedmont maximums again in the middle 90s with the potential for apparent temperatures in the lower 100s. We are still expecting a slight drying trend with respect to PWAT values so the overall cvrg of diurnally fired deep convection should be back to climatology, if not a little less, especially in the Piedmont. Given the probability of a decent amount of dry air above the developing moderate instability and weak steering flow, individual storms will have the capability to produce damaging wind gusts and locally excessive rainfall. Even though there looks to be little change in the magnitude and positioning of upper ridging on Tuesday will be begin to back away from the very hot conditions. With what is looking like an increase in llvl Atlantic fetch, the potential for numerous showers and thunderstorms is back in the picture. && .LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/... As of 130 PM Saturday: The general pattern atop the region thoughout the latter half of next week is shaping up to be pretty typical for mid-July. This will feature a weak mid/upper level flow regime thanks to lingering upper anti-cyclone, along with a broad south- southwesterly llvl flow around Bermuda high pressure. Daily temperatures are expected to be within a category of climo with daily, diurnally enhanced showers and thunderstorms becoming numerous, especially in the afternoon and evenings. && .AVIATION /18Z SATURDAY THROUGH THURSDAY/... At KCLT and elsewhere: A typical summer day around these parts. Already seeing numerous showers and storms over the higher terrain and starting to move off the Blue Ridge Escarpment, and in typical fashion, the storms should blorp out across the Upstate and western Piedmont through the early evening before using up all the buoyant energy around sunset. The PROB30s have been upgraded to TEMPOs at all terminals, and the timing has been adjusted based on the model depiction of convective evolution, which agrees with observations and climo. Expect strong variable winds and IFR vis in the storms. We should have only convective debris remaining overnight with light/var winds. Low stratus/fog is a good bet in the mtn valleys around KAVL, possibly as low as LIFR in the pre-dawn hours. Sunday should be very similar. Only KCLT gets a mention of precip Sunday late in the afternoon because of the late development over the mtns. Outlook: Typical summertime weather is expected into early next week, with scattered to numerous thunderstorms mainly in the afternoon/evening and fog and/or low stratus possible each morning. && .GSP WATCHES/WARNINGS/ADVISORIES... GA...None. NC...None. SC...None. && $$ SYNOPSIS...CSH NEAR TERM...PM SHORT TERM...CSH LONG TERM...CSH AVIATION...PM