948 FXUS61 KRNK 061427 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA Issued by National Weather Service Raleigh NC 1027 AM EDT Sat Apr 6 2019 .SYNOPSIS... Weak high pressure will be over the Mid Atlantic region today and tonight. A low pressure system over the Plains today will move east into the Great Lakes on Sunday then will bring a cold front through the region Tuesday. Then the next storm system from the central United States will impact the east on Friday. && .NEAR TERM /THROUGH TONIGHT/... As of 310 AM EST Saturday... Morning soundings show moisture in the lowest 1000 feet. Latest satellite and weather CAMs also showing low clouds eroding as drier air works in. Will lean toward more sunshine as we head into the afternoon, but expect mix of sun and clouds. High-res models continue to highlight isolated showers forming along the Blue Ridge especially north of Roanoke by late afternoon. Previous valid discussion... Bufkit forecast soundings from various models showed cloud cover for most locations in southwest Virginia, southeast West Virginia and northwest North Carolina becoming scattered between noon and 3PM. Clouds will fill back in overnight across much of the region. Blend of MAV/MET guidance will be starting point for overnight low temperatures. && .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... As of 305 AM EST Saturday... A wedge of high pressure, centered off the Mid Atlantic Coast, may hang over the area into Sunday morning, possibly longer. A warm front and light precipitation will glide over this wedge, enhancing it along and east of the Blue Ridge. The lower resolution models (GFS/ECM) have the wedge removed by sunrise. Whereas the NAM maintains the wedge and southeasterly flow across the mountains through the morning, eroding east by mid afternoon. All models are showing westerly flow aloft (500 mb) with little pressure falls over the Ohio Valley. This pattern favors the wedge holding on longer. With this in mid, will lean Sunday's forecast towards the 00Z NAM. Temperatures along the Blue Ridge Sunday morning will hold steady in the upper 50s, then get a late day spike into the upper 60s. Slightly warmer morning temperatures across the Piedmont, ending the day in the lower 70s. Areas outside of the wedge (Bluefield-Mountain Empire) will see a normal diurnal curve with afternoon highs peaking in the upper 60s to lower 70s. The warm front and associated rain tracks north of the area Sunday evening. Meanwhile, a closed low will develop across the Southern Plains. Since we are in between systems Sunday night into Monday morning, there will likely be a lull in the rain, but will continue to be damp with low clouds and areas of fog. The closed low edges eastward to the low-mid Mississippi Valley Monday. A series of short waves ahead of the low will increase the chance for showers across the area Monday afternoon. Along with dew points in the 60s and afternoon heating, the chances for the area's first-of-the-year thunderstorms threat will be upon us. The occluded low will continue to edge eastward across northern Mississippi and northern Alabama Monday night. With lose of heating, thunderstorm chances diminish across the mountains Monday evening, but may hang over Southside VA and northwestern North Carolina into the early morning hours Tuesday. Some locally heavy rain is possible Monday afternoon and Monday night. Since the bulk of the clouds and rain do not enter the area until the afternoon, Monday's high temperatures will warm into the 70s, pushing near 80F toward Southside. && .LONG TERM /TUESDAY THROUGH FRIDAY/... As of 1230 PM EST Friday... On Tuesday, a closed upper low will be poised to head eastward from over the Tennessee Valley to the coast of the Carolinas, thus bringing its associated cold front into and through our region. In advance of this system a generous fetch of Gulf of Mexico moisture will be advecting into the area on increase 850 mb winds. While showers look very probable across the area, isolated thunderstorms also cannot be ruled out. Forecast afternoon surface based CAPE values are expected to be in neighborhood of 1000 - 2000 J/Kg just as the associated front is crossing the area. High pressure is expected to build into the area in the wake of the Tuesday-system. This is expected to bring dry weather to the area for the latter half of Tuesday night, Wednesday, Wednesday night, and Thursday morning. Tuesday evening parts of the area still may have some lingering showers associated with the departing cold front, especially the southeastern sections of the forecast area. Thursday afternoon through Friday model guidance becomes a bit more variable in terms of timing and positioning of the main synoptic features. What is consistent among the solutions is a trend for the center of the next upper level trough/low to remain close to the U.S./Canadian border. The biggest question is not whether it will have an associated cold front or not, or if it will cross our area, but more of timing of this feature and sensible weather influence on our area. A consensus forecast offers late Thursday night into early Friday as the time frame with isolated to scattered coverage of showers, especially across western and northern sections of the forecast area. Temperatures during the Tuesday through Thursday portion of the forecast are expected to be around ten to fifteen degrees above normal. By Friday, readings will be closer to normal, or about five degrees above normal. Forecast confidence during the Tuesday through Thursday timeframe is moderate with low to moderate confidence on Friday. && .AVIATION /15Z SATURDAY THROUGH WEDNESDAY/... As of 720 AM EDT Saturday... Widespread IFR to MVFR stratus and fog across Virginia and North Carolina this morning. Satellite pictures showed holes in the cloud cover over southeast West Virginia close to KLWB and KBLF. Gradually improving conditions on today as the surface based wedge dissipates. KBCB/KROA/KDAN and KLYH should become VFR between 17Z/1PM and 19Z/3PM. Winds will be light today. A low level jet increases from the south late tonight so the highest ridges of the central Appalachians will have wind speeds of 10 to 15 knots toward 12Z/8AM Sunday. Confidence above average on the wind and visibility. Confidence below average on the timing of the erosion of the low clouds today. EXTENDED AVIATION DISCUSSION... MVFR/IFR conditions are possible with scattered showers and isolated thunderstorms Sunday through Tuesday. Drier weather and VFR ceilings and visibilities are expected Wednesday into Wednesday night. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AMS NEAR TERM...AMS/WP SHORT TERM...RCS LONG TERM...DS AVIATION...AMS/KK BACKUP FORECASTER...JJM