726 FXUS62 KCAE 291750 AFDCAE Area Forecast Discussion National Weather Service Columbia SC 150 PM EDT Mon Mar 29 2021 .SYNOPSIS... Cool, dry weather and clear skies expected today as surface high pressure moves into the region. Moisture will increase by late Tuesday and showers and thunderstorms are expected Wednesday and Wednesday night as a cold front moves through the region. A strong canadian high pressure area will build over the region late week with below normal temperatures but dry conditions expected into the weekend. && .NEAR TERM /THROUGH TONIGHT/... High pressure remains firmly entrenched across the area with a cold front well off the coast. Clear skies have resulted with temperatures below normal and a light northeast wind becoming easterly as the center of the high slides into the Coastal Plain. Expect highs to rise into the mid to upper 60s with some typically warmer locations into the low 70s. Tonight, winds should become fairly light. A warm front well to the south of the area will begin lifting northward but fairly good consensus among HREF members that moisture stays to the south through tonight with limited clouds in the southern forecast area before sunrise. As a result, have trended overnight lows down a bit incorporating our local radiation scheme as a favorable night for radiational cooling is expected. Lows expected to be in the low to mid 40s with some cooler locations dropping into the 30s. Too warm for any frost concerns tonight, especially with warmer soil temperatures. && .SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/... Tuesday and Tuesday night...Surface pressure ridge centered off the Mid Atlantic region extending into the region. Latest models indicate the air mass early in the day will be relatively dry with precipitable water less than 1 inch. The deeper moisture near the coast along frontal boundary. In the afternoon as the ridge weakens, a warm front will lift northwest into the SC Piedmont and moisture will increase across the region. There is a short wave trough moving northeast across eastern Ga and SC but the lift appears limited. The models appear drier for Tuesday than previous runs especially the ECMWF. So lowered pops a bit especially north Midlands but a few scattered showers possible mainly in the CSRA through the afternoon and into the evening as the moisture flux/isentropic lift increases. Max temps should be near or above normal in the mid 70s. Amplified upper trough from the upper Midwest to the southern Plains moving east and cold frontal boundary moving from the Mississippi Valley into the Tennessee Valley overnight. Scattered showers possible with continued isentropic lift but mainly in the Upstate closer to the front. Overnight temps near mild near 60 degrees with relatively strong south winds in the boundary layer. Wednesday and Wednesday night... Cold front will be approaching the region late Wednesday with frontal passage expected late at night. The Nam model appears to be the slower deterministic model with frontal passage. Moderate instability ahead of the front and relatively strong deep layer shear especially in the north Midlands. Synoptic lift appears strongest in the evening. Strong thunderstorms will be possible as the front moves through. NBM pops high and will continue that forecast. && .LONG TERM /THURSDAY THROUGH SUNDAY/... The ensemble guidance is indicating a cold and dry air mass of Canadian origin will build into the region early in the period. Much colder than normal temperatures expected with a freeze possible both Friday morning and Saturday morning. Some wind expected Thursday night may keep temps up a bit but near calm Friday night with strong pressure ridge over the area. The ensemble probability of a freeze highest in the north Midlands those mornings. High confidence strong pressure ridge and dry air mass will remain over the area through the weekend. Slow moderating temperatures expected. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... VFR conditions likely through the 24 TAF period. High pressure remains over the area as light northeast winds shift to more easterly through this evening but remain around 5kts, becoming light tonight. Clear skies will remain in place through tonight before a warm front to the south begins to lift northward towards the forecast area. Some scattered clouds around 3kft are possible, but confidence is low in any restrictions before 18z, although it would be most likely at the Augusta terminals. Winds once again out of the east early tomorrow, around 5kts. EXTENDED AVIATION OUTLOOK...Another system approaches late Tuesday and Wednesday bringing increasing potential for restrictions. && .HYDROLOGY... Area rivers continue to run at bankfull or higher due to heavy rainfall over the past several days, mainly in the Upstate and western North Carolina. Minor to moderate flooding continues along the Saluda River, Congaree River, Great Pee Dee River. Flooding along Lake Wateree is expected to develop on Monday. For the latest river flood warnings, see our web page at www.weather.gov/cae && .CAE WATCHES/WARNINGS/ADVISORIES... GA...None. SC...None. && $$