Area Forecast Discussion
Issued by NWS Columbia, SC

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000 FXUS62 KCAE 301049 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 649 AM EDT Thu Mar 30 2017 .SYNOPSIS... Moisture return, daytime heating, and a stationary front will provide a chance of showers and thunderstorms this afternoon and evening. The front will lift north as a warm front tonight ahead of an upper trough and cold front that will move through Friday morning, providing a continued chance of thunderstorms, possibly severe. Drier air will enter the region behind the departing system Friday afternoon, with high pressure building into the Mid Atlantic ensuring fair weather through Sunday. Next system to affect us Monday and provide a chance of showers and thunderstorms. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Early morning weather analysis indicates a deep closed upper low over Kansas with a cold front extending southward through Arkansas and Texas while a warm front was situated across Tennessee into central Georgia. Satellite imagery shows coastal stratus has expanded northwestward into the Midlands associated with moist onshore low level flow. Weak ridging down the east coast will shift offshore today as the warm front to our south lifts northward with southerly flow developing ahead of the approaching upper low. Despite morning cloudiness, expect low clouds to break when the inversion breaks and stratus deck will transition to stratocumulus or cumulus as surface heating takes place and instability develops. Moderate instability is forecast this afternoon across the Midlands/CSRA with lifted index values around -5C and CAPE values around 1000-1500 J/kg. Hi-res models are in reasonable agreement showing convective initiation occurring around 18z-19z and expanding across much of the southwestern two-thirds of the forecast area. Shear is not great but could be sufficient enough to sustain isolated severe thunderstorms from convection that initiates in the vicinity of the warm front which will provide a focus for the convection. Cold air aloft with 500mb temps around -14C and wetbulb zero height around 10kft will support a marginal large hail threat along with isolated damaging wind gusts. SPC has outlooked the forecast are in a marginal risk with the slight risk just to our west. Temperatures are challenging today with low clouds in place this morning and temperatures starting off quite warm in the lower 60s. Just a couple of hours of sunshine after the clouds break should allow temperatures to rise into the mid-upper 70s with lower 80s in the CSRA. Depending on how early and where convection initiates, that may limit temperatures as well. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/... Main focus will be on thunderstorm chance and severe weather potential tonight into Friday morning. Upper trough will move through late tonight/Friday morning. Surface front to begin lifting north as a warm front ahead of the approaching system/cold front. Though some diurnal stabilization expected, sufficient instability combined with considerable shear expected to provide a severe threat. SPC has our FA in a MRGL to SLGT risk of severe. Cold front to move through by Friday afternoon, with drier air filtering into the region. Breezy conditions possible Friday afternoon. && .LONG TERM /SATURDAY THROUGH WEDNESDAY/... Upper ridge will shift into the SE CONUS Sat/Sun, while surface high builds into the Mid Atlantic, ensuring fair weather for our FA. GFS/EC indicate next upper trough/surface front and moisture return to provide a chance of showers and thunderstorms Mon/Mon nt into Tue time frame, with another system possible late in the forecast period or just beyond. && .AVIATION /12Z THURSDAY THROUGH MONDAY/...
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High confidence in MVFR ceilings at the beginning of the 24 hr forecast period with IFR ceilings also possible late tonight. Fog channel satellite imagery showing widespread stratus over the Midlands and CSRA and expect clouds to continue to be over all terminals through 15z resulting in MVFR cigs. The exception may be OGB which is on the edge of the clouds now but redevelopment is likely. Vsbys never went down due to winds staying up and not expecting them to drop through sunrise. A weak warm front south of the area will lift northward into the Midlands today and provide a focus for convection after 16z. Expect all terminals to be affected by convection with showers and scattered thunderstorms between 18z-00z. Hi-Res models providing some possible timing of thunderstorms so have included a tempo group for thunder at each site covering a 3 hour window. Strong and damaging winds will be possible with the thunderstorms. Restrictions should return overnight with low clouds redeveloping at least at CAE/CUB as some wedge conditions try to re-establish before the stronger upper system arrives towards morning Friday which will bring another chance for showers and storms. Did not mention thunder at this time for the second round of convection as there is some uncertainty it will impact terminals. EXTENDED AVIATION OUTLOOK...Restrictions possible in showers and thunderstorms Friday and on Monday as cold fronts cross the region.
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&& .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$

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