Sunrise 6:19 AM   Sunset 8:05 PM Moonrise 3:17 AM   Moonset 3:22 PM

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FXUS62 KRAH 040725 AFDRAH

Area Forecast Discussion National Weather Service Raleigh NC 320 AM EDT Sat May 4 2024

SYNOPSIS
A series of upper level disturbances will move through the area through Sunday. Meanwhile, a backdoor cold front will stall across the area through tonight, before lifting north into Virginia early Sunday.

NEAR TERM /THROUGH TONIGHT/
As of 320 AM Saturday...

A quasi-stationary surface front will meander across the northern third of the forecast area through the evening, before lifting north into VA tonight/early Sunday. While weak, subtle disturbances are currently moving through the area, a more prominent shortwave trough/vort cluster, currently over AL, will progress NEWD across central NC during the late afternoon and into tonight. The accompanying moisture feed will propel precipitable water values towards daily maximum values of 1.5-1.7" inches, highest across the NC Piedmont counties. As disturbances begin to interact with the the stalled frontal zone, models indicate a weak sfc wave will develop and will likely enhance lift and precip across the area.

Intermittent showers will spread SW to NE across the area throughout the day and into the evening and overnight hours, with the greatest coverage and frequency of rain expected along and west of US 1. It's entirely possible that that the eastern Sandhills and southern coastal plain counties could remain largely dry until the shortwave trough advances into eastern NC overnight/early Sunday.

Widespread clouds and rain will significantly temper insolation with resultant weak buoyancy leading to some embedded thunder at times, especially as the primary MCV tracks through the area during the late afternoon and evening. Given equally weak shear, no severe storms are expected. Rainfall amounts through tonight will range from 0.75-1.0" in the NW Piedmont, to 0.25-0.50" across the Triangle, to less than a tenth of an inch across the southern coastal plain.

Highs will greatly depend on both the location of the front and the spatial and temporal trends of rainfall through the afternoon. A shallow wedge of cooler air/ hybrid CAD is likely along and north of the front with a potential for low cloud ceilings/stratus to persist across the far northern/northwestern zones. Highs ranging from lower 70s NW(potentially cooler) to lower/mid 80s SE. Lows tonight 60-65.



SHORT TERM /SUNDAY AND SUNDAY NIGHT/
As of 320 AM Saturday...

The quasi-stationary front sagging across northern portions of the forecast will retreat north early Sunday, leaving all of central NC in the warm sector. The increasingly sheared shortwave trough will exit east of the area during the early afternoon.

Ongoing scattered convection Sunday morning within the continued anomalously moist PWATs should experience some re-newed vigor during the afternoon as weak diurnal buoyancy flares up. Continued weak shear will deter any severe potential. Rainfall amounts will be more equitable Sunday, with 0.2-0.3" expected area-wide.

Under mostly cloud skies, highs ranging from mid/upper 70s north to lower 80s SE. Convection should largely dissipate as BL nocturnally cools and stabilizes. Mild overnight temps in the 60s with stratus likely to re-develop across the area as moisture remains high.

LONG TERM /MONDAY THROUGH FRIDAY/
As of 250 AM Saturday...

The extended forecast will feature a continued chance of unsettled weather to start the week Mon, followed by somewhat drier and hot temperatures by the middle of the week. A potent late-week system/trough looks to increase storm chances again by week's end.

On Monday, models continue to show a shortwave over the TN valley tracking east across the region in the afternoon/evening, before exiting along the coast by Tue morning. A surface Piedmont trough will be in place and combined with 200-percent of normal PW's should favor another day of scattered to perhaps numerous showers and storms, maximizing during peak heating. Instability is between 500- 1000 J/kg but shear is weak, so severe chances are not expected, though slow-moving storms could bring heavy rain. Activity should wane overnight with loss of heating and as the trough slides toward the coast. Highs should hover in the low/mid 80s with higher rain chances and cloud cover.

As the trough moves to our east Tue, weak ridging starts to build in, although the CMC/GFS show a weak perturbation riding along the ridge. With a lack of large-scale forcing, confidence on coverage of storms, if any, is low, such that storm activity should be isolated/scattered in nature and focused along differential heating boundaries and/or the sea-breeze. Highs should warm to the low to upper 80s.

A drier pattern still appears to be favored midweek Wed and part of Thu as ridging and southwest flow builds back into the region. This will also be when the airmass will warm quite a bit with a lee trough setting up east of the Appalachians and low-level thicknesses well above average and highs some 12-15 degrees above normal in the upper 80s to low 90s. The NBM still indicates a 60-80 percent chance of 90 or greater maxT values across portions of the Sandhills, Triangle region, and Coastal Plain during this period. Heat index value could reach the mid 90s over these areas, making for an early taste of summer. While this period looks drier, most guidance shows a developing trough over the upper MS valley Thu, with solutions indicating a decent plume of moisture tied to a perturbation advecting ahead of a cold front draped over the OH valley. This would favor better chances of isolated/scattered storms Thu aftn/eve with higher instability coupled to higher shear.

Although model solutions diverge by late in the week with a frontal system location, there is broad consensus that chances of storms appear to remain elevated to close out the week as the trough slides closer to the TN/OH valley and Great Lakes region with instability/shear still favorable over the Carolinas.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/
As of 220 AM Saturday...

A back-door cold front, noted by a E-NELY wind shift, will settle south across the northern TAF sites over the next few hours before stalling. Moisture pooling along the front should lead to the development of IFR to MVFR ceilings at all TAF sites 08 to 12z.

Ceilings at KFAY, KRDU, and KRWI should gradually lift to VFR from south to north through 17-18z, with scattered showers and storms possible during the afternoon and evening, especially at KRDU.

At KGSO and KINT, ceilings could remain IFR to MVFR through the afternoon and evening as intermittent showers and storms develop and move through the area through much of the forecast period.

Showers will linger across the area tonight, with the re-development of LIFR to MVFR conditions across the area, lowest at KINt and KGSO where the deepest moisture resides. -CBL

Outlook: IFR-MVFR ceilings are likely to redevelop each night- morning through Monday, as are scattered to locally numerous showers/storms each afternoon-evening. -MWS

CLIMATE

Record High Minimum Temperatures:

May 4: KGSO: 65/2022 KRDU: 68/1938 KFAY: 68/1942

RAH WATCHES/WARNINGS/ADVISORIES
None.

Conway
Click for Map
Sat -- 12:10 AM EDT     1.37 feet High Tide
Sat -- 04:14 AM EDT     Moonrise
Sat -- 06:23 AM EDT     Sunrise
Sat -- 06:36 AM EDT     0.21 feet Low Tide
Sat -- 12:38 PM EDT     1.39 feet High Tide
Sat -- 04:20 PM EDT     Moonset
Sat -- 07:04 PM EDT     -0.15 feet Low Tide
Sat -- 08:02 PM EDT     Sunset
Tide / Current data from XTide NOT FOR NAVIGATION

Conway, RR. bridge, Waccamaw River, South Carolina, Tide feet

Grahamville
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Sat -- 01:08 AM EDT     1.10 feet High Tide
Sat -- 04:14 AM EDT     Moonrise
Sat -- 06:23 AM EDT     Sunrise
Sat -- 07:40 AM EDT     0.17 feet Low Tide
Sat -- 01:36 PM EDT     1.11 feet High Tide
Sat -- 04:19 PM EDT     Moonset
Sat -- 08:02 PM EDT     Sunset
Sat -- 08:08 PM EDT     -0.12 feet Low Tide
Tide / Current data from XTide NOT FOR NAVIGATION

Grahamville, Waccamaw River, South Carolina, Tide feet

Full Color Weather Map

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