Area Forecast Discussion
Issued by NWS Raleigh/Durham, NC

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
337 FXUS62 KRAH 271512 AFDRAH Area Forecast Discussion National Weather Service Raleigh NC 1112 AM EDT WED JUL 27 2016 .Synopsis... Strong high pressure aloft will extend across the region through Thursday, bringing continued hot and humid conditions to central NC. The chance for afternoon storms will increase toward the weekend. && .NEAR TERM /Through THursday/... As of 1112 AM Wednesday... Today: Persistent mid/upper level anticyclone located just to the south/southeast of central NC will continue to provide the region with hot and humid conditions with another day of afternoon temps in the mid to upper 90s and heat index values in the 103-109 degree range (highest east and south again). Given the consecutive days of heat index values of around 100/low 100s across the northwest piedmont and warm overnight lows have decided to expand the heat advisory to encompass the entire area. Strong surface heating within the high PW air mass in place will support isolated to scattered convection this afternoon, though the remnant outflow boundary from last night`s convection could lead to convective initiation. Proximity to the modest 30kt mid-level flow over the Mid-Atlantic states, on the northern periphery the upper anticyclone, could support a few severe clusters, especially across the northern half of the forecast area. The primary threat again will be locally damaging wind gusts. Given PW`s around 2 inches+ heavy rain will be possible, with a threat of localized flooding if any clusters slowly track across an urban area. Tonight: Most convection will generally die off by late evening with another warm night expected. Expect lows temps tonight to generally be in the mid to upper 70s. Can`t completely rule out additional weak disturbance tracking across northern portions of the area overnight, possibly sparking a shower or storm, though think any activity will be quite isolated as we should still be under the general influence from the nearby mid/upper level ridge. Thursday: The persistent mid/upper level ridge will again provide central NC with another hot and humid day for Thursday, with a the main threat of storms across the northern half of the area again. Additional strong to severe storms will be possible in the late afternoon/evening, with the main threat again from locally damaging wind gusts along with a localized flooding threat (mainly urban areas) and dangerous cloud to ground lightning. Expect high temps will gain be in the mid to upper 90s, with similar heat index values and likely another heat advisory. && .SHORT TERM /Thursday night and Friday/... As of 325 AM Wednesday... Model guidance in good agreement in their depiction of a s/w lifting newd from the TN valley Thursday night, and into the Mid Atlantic Friday. This feature will aid to enhance low level confluence along a surface trough across the NC Piedmont, and lead to a decent chance for scattered convection, especially during max heating Friday afternoon. May see a few showers/t-storms late Thu night in vicinity of the NW Piedmont. Max temps Friday dependent upon extent of morning cloudiness and when convection erupts. Currently favor max temps lower 90s nw to the mid/upper 90s east and south. This suggest a possible continuation of advisories for heat along the i-95 corridor. Remaining very warm and muggy overnight with temps in the mid-upper 70s. && .LONG TERM /Friday night through Tuesday/... As of 325 AM Wednesday... The lead s/w will lead to an eventual shift in the upper air pattern, with a suppression of the upper ridge, and the development of an upper trough, extending from New England into the Carolinas. During this transition, expect a series of s/ws to cross through our region, sparking scattered convection. Difficult this far out to pinpoint a particular time when convective coverage will be greatest, though current indicators point toward the end of the weekend into early next week. For now, will refrain from likely PoPs, and cap PoPs at high chance. Potential for locally excessive rainfall to occur by late in the weekend or early next week as deep sw flow develops, suggesting potential for storms to train repeatedly across the same location. Since expecting more clouds and scattered convection, and upper ridge being suppressed well to our south, should see a trend of max temps returning to near normal levels. Thus expect max temps to trend from the low-mid 90s Saturday to the upper 80s/lower 90s early next week. && .AVIATION /12Z WEDNESDAY THROUGH SUNDAY/... As of 645 AM Wednesday... VFR conditions are generally expected to continue this morning as the disturbance responsible for yesterday evenings convection pushes off to the east of the area, allowing for clearing skies this morning. Expect another round of convection this afternoon under similar heat and moisture conditions, mainly across the northern tier during the mid/late afternoon. However, we may see a few showers and storms first develop along a remnant outflow boundaries left from yesterdays convection from near KFAY back west-northwestward to south of the KGSO/KINT. Any storms that develop today will have the potential to produce gusty winds and sub-VFR conditions. Convection should begin to wane again by mid to late evening, with generally dry conditions by early Thursday morning. Patchy sub-VFR fog and/or stratus will be possible again on Thursday morning, especially at locations that pick up appreciable precip today. Outlook: Mostly VFR conditions are anticipated, although late night and early morning MVFR fog is possible each day through Fri, with a better chance of sub-VFR fog/stratus Sat/Sun. Isolated to scattered showers/storms are expected each afternoon/evening through the end of the week, with increasing chances by the weekend. && .RAH WATCHES/WARNINGS/ADVISORIES... Heat Advisory from noon today to 8 PM EDT this evening for NCZ007>011-021>028-038>043-073>078-083>086-088-089. && $$ SYNOPSIS...WSS NEAR TERM...CBL/BSD SHORT TERM...WSS LONG TERM...WSS AVIATION...BSD/mlm

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.