448 FXUS62 KRAH 231025 AFDRAH AREA FORECAST DISCUSSION National Weather Service Raleigh NC 630 AM EDT Fri Apr 23 2021 .SYNOPSIS... Cold high pressure will push east off the NC coast today. A low pressure system will track from the Gulf Coast states across the Southeast states Saturday into Saturday night, bringing widespread rain. High pressure will follow Sunday and Monday, which will start a warming trend. && .NEAR TERM /THROUGH TONIGHT/... As of 230 AM Friday... ...Freeze Warning continues across the northern tier of the Piedmont, with a Frost Advisory elsewhere through 900 AM this morning... High pressure over the region this morning will finally exit to the east and offshore later today. After a frosty start, much milder conditions with mostly sunny to partly sunny skies are expected this afternoon. Highs are expected to warm into the mid to upper 60s. Light and variable winds will become southwest around 10 mph late morning into the afternoon. The storm system taking shape over the Southern Plains will quickly move ENE toward MS/AL by tonight. A WAA pattern will quickly develop out ahead of this system tonight across the Gulf Coast states toward the southern Appalachians. For our region, an increase in high cloudiness can be expected this evening, with mid clouds arriving overnight. There is a slight chance of light rain by daybreak across the SW Piedmont. A light S-SW wind under 10 mph is expected. Lows may occur around midnight or so in the NE where the residual cool and stable layer will still exist. Thickening and lowering of the cloud base later will keep temperatures mild elsewhere. Lows generally in the 40-45 range NE and 45-50 expected elsewhere. && .SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/... As of 249 AM Friday... A Marginal to Slight Risk of Severe Storms Saturday afternoon and early evening (mainly in the SE). A widespread soaking rain with QPF of 0.5 to locally 1 inch expected. Showers are expected to be widespread in the WAA pattern from the southern Appalachians NE across western and southern NC between 12z and 15z Saturday. The influx of moisture will also be aided by the remnants of a likely decaying MCS that is expected to track across MS/AL into GA and upstate SC late tonight. Therefore, widespread showers and cloudiness will obviously have an impact on the potential severe storm threat later in the afternoon into the early evening across our region. SPC currently depicts a "Slight Risk" over our S-SE tier of counties and a "Marginal Risk" as far north and west as the portions of the Triad and Triangle Areas. The severe threat will depend a lot on how much rainfall and subsequent stabilizing of the lower levels occurs during the day, then how much destabilization can return in the afternoon and evening. The north and west extent of this severe threat may very well be trimmed back in later forecasts given our high potential for in-situ CAD and stable boundary layer in the Piedmont. To the east and south, there is a chance that the warm front may be able to slip up into areas from near Laurinburg/Fayetteville to Goldsboro late in the day. If so, then there would obviously be an increased risk of severe weather with convection that forms upstream over GA/SC during the afternoon - then tracks E or ESE during the late afternoon and evening. Some of the hi-res models suggest that very scenario. For now, we will keep the high POP for showers spreading NE throughout all of our region between 12z-18z, then gradually decreasing from the west during the afternoon. Then, a renewed chance of showers and possibly thunderstorms during the mid/late afternoon, mainly across the southern Piedmont/Sandhills and SE Coastal Plain. The SE quadrant will have the highest potential for severe storms during the late afternoon and early evening. Highs should be in the 50s NW-N, potentially ranging to near 70 SE. The chance of showers/storms will end late Saturday evening. This will be followed by a chance of fog as the winds will be light prior to the cold frontal passage late at night or early Sunday morning. Lows generally in the 50s. && .LONG TERM /SUNDAY THROUGH THURSDAY/... As of 230 AM Friday... Much of the upcoming week looks to be dry with above normal temperatures and sunny skies. The departing upper trough axis should be offshore by 12Z Sunday, with WNW flow prevailing across the area. A weak shortwave trough will move through the mountains Sunday afternoon but at that point the only sensible weather impact would be a brief increase in clouds and even that looks like a stretch given decreasing PW's. Temperatures Sunday look to be within a degree or two of normal with highs in the low 70s, lows in the mid to upper 40s. Deterministic models and their associated ensemble systems are in good agreement during the Monday - Wednesday time period, leading to a high confidence forecast of above normal temperatures and dry weather through mid week. Monday - Wednesday will see a fairly impressive ridge build across the region with 500mb heights peaking around 582dm Wednesday afternoon. As such, we'll carry 0 PoPs during this period. At the same time, temperatures will be on the increase each day with above normal readings anticipated. Monday should see highs in the mid 70s, Tuesday will see low 80s, and Wednesday/Thursday mid 80s. By Thursday afternoon however, an upper low over the Plains will begin to move eastward with increasing clouds and precip chances overspreading the area Thursday afternoon into Friday morning. Just how quickly this upper trough and associated surface features make it into the Piedmont is still up for debate. Both the GEFS and EC ENS, as well as NBM indicate precip chances at various times Thursday afternoon through Friday night, with the main timing differences due to vastly different evolutions of the parent trough moving through the Ohio Valley and the potential for a closed low overhead. Either way, look for increased rain chances late in the week. Also holding back on mentioning thunder at this point as convective indices look marginal at best. && .AVIATION /12z FRIDAY THROUGH TUESDAY/... As of 630 AM Friday... 24 hour TAF period: Confidence is high for VFR conditions through 09z/Saturday. Scattered to broken layers of high clouds are expected today. Winds will be light, becoming SW 5-10 knots late this morning and afternoon. Looking beyond 09z Saturday: Low pressure system tracking from the Tennessee Valley into the Mid-Atlantic will bring widespread rain and sub-VFR conditions to central NC from west to east beginning Saturday morning. Showers will end on Saturday night, with skies clearing and VFR conditions returning from Sunday through Tuesday. && .FIRE WEATHER... As of 230 AM Friday... Coordination with the NC Forest Service has led to another increased fire danger statement from noon through 700 PM today for the area. Dry conditions will continue under high pressure. The relative humidity values will again dip into the 25-30 percent range this afternoon. Light winds will become southwest at 8-12 mph, with some gusts to 15 mph - especially late morning through the afternoon as the high pressure shifts to our southeast this afternoon. The Special Weather Statement for increased fire danger will run from noon through 700 PM. Widespread showers and higher relative humidities will finally put an end to the very dry conditions and fire danger threat Saturday. && .CLIMATE /APRIL 23 RECORD LOW TEMPS/... As of 230 AM Friday... April 23 Record Low Temperatures: Raleigh: April 23 / 33 in 1986 Greensboro: April 23 / 30 in 1986 Fayetteville: April 23 / 35 in 1927 && .RAH WATCHES/WARNINGS/ADVISORIES... Frost Advisory from 3 AM to 9 AM EDT Friday for NCZ021>028-038>043- 073>078-083>086-088-089. Freeze Warning from 3 AM to 9 AM EDT Friday for NCZ007>011. && $$ SYNOPSIS...Badgett NEAR TERM...Badgett SHORT TERM...Badgett LONG TERM...DL AVIATION...Badgett/Danco FIRE WEATHER...Badgett/JJT CLIMATE...Badgett