Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 260705 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 305 AM EDT WED OCT 26 2016 .SYNOPSIS... Cool high pressure will extend into our region from the north through tonight, before shifting offshore early Thursday. A cold front will move into the area from the northwest Thursday night. && .NEAR TERM /through tonight/... As of 735 PM Tuesday... Strong high pressure centered well to our north (SW of Hudson Bay) at 1036+ mb extended south and southeast deep into Florida tonight. Very dry air was in place over our region and this will be the case tonight and Wednesday with the high in place. Surface dew points have come up since sunset a few degrees into the 40s, except 30s NW. Surface temperatures fall quickly into the lower to mid 50s soon after sunset and this trend will continue. The only cloudiness was associated with the stronger mid/upper NW flow aloft extending from the upper Midwest to the Tennesse and Ohio Valley regions. Most of these clouds were high clouds and were evaporating as they encounter the ridging over the eastern seaboard. Any cirrus overnight should be scattered and thin resulting in no worse than mostly clear skies. Since winds will go calm the temperatures will fall rapidly as mentioned above. Some mixing of the dry air just above the boundary layer will aid in lowering the near surface dew points as the temperatures fall. Expect lows of 35-42 by daybreak, with some scattered frost possible in the low-lying areas around our normally cold spots (including the Roxboro, Louisburg, Rural Hall, and the Yadkin River valley as well). However, the frost is not expected to be enough to damage plants/crops that are still yet to be harvested. A Warning will not be needed at this time. We will add wording in the Hazardous Weather Outlook to indicate more in the way of mid 30s in the rural areas of the Piedmont. No other changes at this time. && .SHORT TERM /Wednesday through Thursday night/... As of 240 PM Tuesday... The axis of the weak shortwave ridge will shift eastward over the Southeast states Wed, as the axis of the Canadian-source surface ridge begins to shift east and off the East Coast. Expect another mostly sunny day with below-normal thicknesses indicating highs in the mid-upper 60s. Milder lows expected Wed night as the return flow around 925-850 mb anticyclones starts to draw low level moisture into the area, advecting first into the western CWA. Lows from mid 40s NE to upper 40s and around 50 far south and west. A fast-moving and strengthening shortwave swinging ESE through the Great Lakes and Northeast Thu/Thu night will help draw a front into NC from the NNW, likely not arriving until late Thu night. Have low confidence in our area receiving any significant precip, considering that the vorticity will be shearing through the mid level trough axis as it passes through, the upper divergence will be minor and mostly to our north, and PW is projected slightly lower than what the models showed yesterday. That said, forecast soundings do show some marginal instability late in the day into the evening, although surface dewpoints may not get quite high enough for anything more than an isolated storm or two. Will stick with low chance pops (20- 35%), higher north and lower south, from mid afternoon through the evening, with the isolated thunder risk confined to the north. Warm sector highs Thu in the 70s. Thu night lows in the 50s, as the front will be delayed until late and may not work much more southward than the northern sections of NC prior to daybreak Fri. -GIH && .LONG TERM /Friday through Tuesday/...
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As of 304 AM Wednesday... Cold front will be near the NC coast by 12z Friday. Lack of CAA will result in high temperatures on Friday similar to those on Thursday. Transitory surface high pressure will build across the area in the wake of the front Friday, before shifting south of the area Saturday. Another cold front will move quickly through the region Sunday. Dry westerly flow aloft with little moisture return will result in a dry passage, followed by weak surface high pressure and upper level ridging Monday and Tuesday. Temperatures will remain above normal through the period, with highs in the 70s.
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&& .AVIATION /06Z Wednesday through Sunday/... As of 105 AM Wednesday... There is a high probability that VFR conditions will exist across central NC through tonight as high pressure extends across the region. This high will drift east late tonight. Southerly return flow on the back side of this high will advect low level moisture into central NC, possibly leading to the development of low clouds or fog by daybreak Thursday. The potential for MVFR/IFR conditions early Thursday will slowly improve to low end VFR or high end MVFR ceilings Thursday afternoon when a few showers are expected to occur ahead of an advancing cold front. This surface front will cross central NC Thursday night, maintaining a threat for a few showers and areas of MVFR ceilings. A return to VFR conditions anticipated for Friday through Saturday as an area of high pressure builds into the Southeast U.S. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...Badgett SHORT TERM...Hartfield LONG TERM...30 AVIATION...WSS is the U.S. government's official web portal to all federal, state and local government web resources and services.