Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

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000 FXUS62 KRAH 261608 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 1205 PM 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 1110 AM Wednesday... Rest of today: Forecast trends are in line with observations this morning. Skies are generally clear across the area and should remain that way for the rest of the day, with little more than some high cloudiness topping the weak shortwave ridge axis which will cross the Southeast states this afternoon. The deep low- to mid-level anticyclone noted from 850 to 700 mb will limit moisture influx and resultantly will limit the amount of convective cloudiness over the area this afternoon. Have nudged highs today upward slightly to the mid 60s to around 70, given that temps are pacing a bit warmer than hourly forecasts. -GIH Previous discussion from 310 AM: An area of high pressure at the surface coupled with a wly flow aloft will maintain dry and seasonably cool conditions across central NC today. Low level thicknesses average about 10m lower than normal, supportive of afternoon temps 3-4 degrees cooler than normal. High temps generally in the mid 60s north to upper 60s south. Aside from a few patches of cirrus, expect sunny skies today. Tonight, the area of high pressure drifts east, while aloft, westerly flow begins to advect moisture ahead of a s/w crossing the Great Lakes. This moisture aloft will be int he form of a cirrus shield gradually spreading/thickening over central NC. Latest model guidance suggest low level moisture advection will not become significant until close to daybreak. Thus, not expecting much in the way of low clouds and/or patchy fog until close to daybreak. The moistening atmosphere will lead to mild overnight temps, mainly in the mid-upper 40s. -WSS && .SHORT TERM /Thursday and Thursday night/... As of 310 AM Wednesday... Atmosphere will continue to moisten Thursday as southerly low level flow continues to pull moisture into our region. While the bulk of the energy associated with the s/w crosses well to our north, the trailing end of the s/w and attendant sfc front will encounter a moderately moist air mass. While instability will be lacking, still cannot rule out a clap or two of thunder across the northern Piedmont late in the day into the early evening hours when best forcing noted in the lowest 15k ft. Have scaled back timing of highest threat for measurable rain until late in the afternoon into the evening. Still, expect rainfall amounts to be light, on the order of less than a tenth of an inch. In spite of extensive cloudiness, afternoon temps will be a few degrees warmer than normal thanks to the low level warm air advection. High temps Thursday 70-75, coolest northwest and warmest far south. Expect the sfc cold front to drift east-se across central NC, mainly during the overnight hours. Should see a gradual decrease in cloudiness nw-se after 06Z. Min temps lower 50s nw to the mid/upper 50s se. && .LONG TERM /Friday through Tuesday/... 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. && .AVIATION /18Z Wednesday through Monday/... As of 1205 PM Wednesday... Confidence is high that we`ll see VFR conditions continuing through this evening, with high pressure nosing into the region from the north and warm/stable air aloft. However, conditions are expected to deteriorate overnight, starting after 06z in the southeast (FAY) and after 08z elsewhere, as low level return flow brings increasing moisture into the low level (under 3 000 ft AGL) surface-based stable layer. A trend to MVFR or IFR cigs is likely late, lasting through 13z, followed by a trend to low-end VFR through 16z, with gusty winds from the southwest developing at all sites. Patchy sprinkles are possible toward the end of the TAF valid period at INT/GSO/RDU, but any sprinkles will be isolated and not impactful to aviation interests. Looking beyond 18z Thu, a few showers with MVFR conditions are possible in the west (INT/GSO) in the 21z Thu to 03z Fri time frame, and in the 00z to 06z Fri time frame elsewhere (perhaps lasting until 09z at FAY/RWI), but VFR conditions should remain dominant with any sub-VFR conditions being very brief with only light precip expected. Sub-VFR shallow ground fog is then possible late Thu night into Fri morning (mainly 08z-13z). A weak cold front will drop southward into the area Fri morning, with high pressure building in behind it from the north. VFR conditions will return by mid morning Fri, holding through the weekend and into early next week, although sub-VFR fog/stratus is again possible early Sat morning and again Mon morning as the high shifts to our southeast and another mostly dry front approaches from the north. -GIH && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...Hartfield NEAR TERM...Hartfield/WSS SHORT TERM...WSS LONG TERM...30 AVIATION...Hartfield is the U.S. government's official web portal to all federal, state and local government web resources and services.