textproduct: Raleigh

WHAT HAS CHANGED

As of 222 AM Wednesday...

* Localized rainfall amounts Thursday could approach 2+ inches along the US-64 corridor

* Above normal temperatures this weekend trending below normal early next week with the potential return of wet weather

KEY MESSAGES

As of 222 AM Wednesday...

1) A period of unsettled weather develops late tonight and continues into Thursday. The wet weather could persist into early Sat within a possible in-situ CAD regime.

2) Mainly dry this weekend with above normal temperatures. A cold front early next week could bring a return to wet weather.

DISCUSSION

As of 222 AM Wednesday...

KEY MESSAGE 1... A period of unsettled weather develops late tonight and continues into Thursday. The wet weather could persist into early Sat within a possible in-situ CAD regime.

A relatively dry day is expected today as return southwest flow will be in full swing across the region. With the surface high over the Atlantic, the flow will bring warmer air into the region. However, mid-high clouds will be prevalent today, making for a difficult temperature forecast. For now, expecting a few degrees above normal in the upper 50s to low 60s. Wind gusts this afternoon may approach 25-30 mph, highest in the Sandhills and Coastal Plain.

A period of wet weather will develop late tonight and continue through most of Thursday as a wave of low pressure along a southward moving frontal boundary approach the region. Deep moisture will overspread the area, with precipitable water values over 200-percent of normal. Aloft, we will see a period of moist upglide riding atop the surface boundary, along with some possible jet enhancement with a jet streak over the NC/VA area. Rainfall amounts with this first frontal wave could range from three quarters of an inch to 1.25 inches, just based on the LREF ensemble. However, some locations could see a half inch or less, depending on where banding may set up. Along these same lines on the higher end, the HREF is picking up on some localized rainfall totals along the US-64 corridor upwards of 2+ inches, likely driven by the jet, DPVA, and weak MUCAPE seen in forecast soundings. Confidence on this high-end scenario is not great, but is not out of the realm of possibilities.

A secondary wave of low pressure is forecast to track along the boundary as the cold front moves south of central NC Thu night and early Fri. The track of this second system still varies amongst the ensemble and deterministic guidance. The more southern solutions bring dry weather to the area Fri, while the northern solutions keep moist upglide over the region Fri and perhaps lingering into early Sat along the Coastal Plain. It would appear the trend in the LREF is for a wetter Fri, particularly over areas along/east of US-1, but uncertainty still remains. If the wetter solutions were to verify, an in-situ CAD regime could setup Fri with temps below normal in the low/mid 50s.

KEY MESSAGE 2... Mainly dry this weekend with above normal temperatures. A cold front early next week could bring a return to wet weather.

Although uncertainty remains in regards to the first half of the weekend with respect to a possible in-situ CAD regime slowly eroding Sat, it would appear most LREF ensemble members favor a drying trend as the frontal boundary continues to sag south of the area. Temperatures should start to then trend above normal, especially by Sun as low-level thicknesses continue to rise beneath developing quasi-zonal flow aloft. Highs on Sun could approach the mid 60s to low 70s.

As we head into early next week, there is at least broad consensus that a somewhat transitory 1040-mb high builds down the Mid-Atlantic region Mon through Tue. A backdoor cold front will accompany this, moving through central NC perhaps by early Mon and setting up a return to below normal temperatures heading into Tue. There is still a large amount of spread with the pattern, and thus temperatures, but there is some agreement amongst the ensembles and machine- learning guidance that a frontal wave may move through early to middle of next week atop the cold wedge. This could favor a return to cloudy/wet weather late Mon into Wed, although it is too soon to discuss precipitation amounts.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

As of 630 AM Wednesday...

VFR conditions should prevail through the day today, with flight restrictions returning tonight. As a 45-50 kt southwesterly jet remains over the region, a brief period of LLWS is likely this morning until shortly after sunrise when the higher winds will start mixing to the surface. This will lead to southwesterly gusts in the 20s kts during the daylight hours, diminishing around sunset. A few gusts over 30kts will be possible as well. Flight restrictions will return tonight, as MVFR to IFR ceilings along with rain and associated visibility restrictions move into the region from the west shortly before 06Z. Ceilings may not lower in the south (FAY) until around or just after 12Z Thursday. However, periods of LIFR ceilings are possible, especially in the Triad terminals (INT/GSO).

Outlook: Flight restrictions and rain are expected Wed night through early Friday, as a couple of frontal zones merge and move slowly across the region. Low clouds and a risk of morning drizzle may then linger into Sat, though forecast confidence by that time is only low- medium.

RAH WATCHES/WARNINGS/ADVISORIES

None.