textproduct: Raleigh

SYNOPSIS

A front will hold to our southeast through the weekend, as weak high pressure settles over North Carolina and the Mid Atlantic region. An Arctic cold front will move southeastward through the area on Monday.

NEAR TERM /TODAY THROUGH TONIGHT/

As of 120 PM Saturday...

* Patchy light rain in the far southeast this afternoon, otherwise dry. * Areas of dense fog likely tonight.

* Below normal temperatures expected.

A frontal system remains stalled off the NC coast, with the associated low pressure well to our northeast. This has left weak high pressure over the region. This should keep the majority of central NC dry, with exception of the far southeast where patchy light rain associated with the frontal boundary looks to be possible over the next several hours. Temperatures this afternoon will stay below normal for this time of year and are generally expected to reach the low to mid 40s.

Additionally, in the overnight hours dense fog looks to be probable. The HREF is showing the probability of visibilities less than 0.5 miles between about 50-70% for much of the region, with the higher probabilities focused mostly in the southwest and to a lesser extent the northeast regions of the CWA. Low temperatures overnight look to dip at or below freezing everywhere, with mid/upper 20s in the north. This means that anywhere fog may develop, freezing fog is possible when temperatures are at and below freezing.

SHORT TERM /SUNDAY THROUGH SUNDAY NIGHT/

As of 120 PM Saturday...

* Continued fog expected into the morning hours.

* Temperatures slightly warmer than today, but still below normal.

Weak high pressure will continue to pass through the mid-Atlantic through the day on Sunday ahead of an approaching trough and associated cold front. Through the morning hours, areas of potentially dense fog will slowly dissipate with the daytime heating. After fog dissipates, partly cloudy skies are expected throughout the afternoon, with increasing cloudiness overnight as the cold front approaches. Increased low level thicknesses will support slightly warmer temperatures on Sunday. Thus, highs are expected to reach the upper 40s to low 50s, with lows dipping in the upper 20s to mid 30s. While most of the precipitation with the front looks to hold off until after daybreak on Monday, there is a possibility of some very light rain reaching western portions of the region late Sunday night. Temperature profiles do not look conducive of any wintry precipitation before sunrise on Monday at this time.

LONG TERM /TUESDAY THROUGH SATURDAY/

As of 130 PM Saturday. . .

-Chilly, below average temperatures expected Mon-Tues. -Light wintry mix possible Monday mainly across northern Piedmont. -Another chance for precip late Thursday into Friday.

A cold front will move across the region on Monday, with cold air chasing the departing precipitation through the day. Morning temperatures will start near freezing along the VA border and in the mid to upper 30s elsewhere. Rain will be the primary precipitation type, but temperatures will gradually fall through the afternoon as colder air arrives. This may allow for a rain/snow mix across portions of the northern Piedmontgenerally from Rocky Mount to Raleigh to Lexington. Before precipitation tapers off early Monday evening, a brief changeover to light snow is possible near the VA border. Any accumulations would be minor and mainly limited to elevated surfaces given warm ground temperatures. All precipitation will exit the region by Monday evening. By Tuesday morning, surface high pressure will settle over the Mid- Atlantic. A surge of overnight cold air will allow temperatures to drop into the upper teens to low 20s. With light to calm winds, any leftover moisture on roads may freeze, creating the potential for black ice during the Tuesday morning commute. High pressure will dominate Tuesday and Wednesday, supporting dry weather. Highs both days will range from the low to mid-40s. Lows will fall into the 20s Tuesday morning and into the mid to upper 30s Wednesday morning. Late in the week, another shortwave will move across the northern US, bringing increasing precipitation chances. While guidance shows some spread in the timing, track, and moisture availability, the general consensus suggests precipitation could return by late Thursday afternoonmainly across the NW Piedmontbefore a front sweeps through the region on Friday. Conditions should dry out again by Saturday morning. Behind the front, highs on Saturday will be cool, in the upper 30s to low 40s, with another round of lows in the upper teens to low 20s Saturday morning.

AVIATION /00Z SUNDAY THROUGH THURSDAY/

As of 730 PM SATURDAY...

Widespread IFR to low MVFR stratus currently persists across the Sandhills and Coastal Plain (including FAY and RWI), but it will continue to erode from NW to SE, providing a brief window opportunity for VFR conditions there over the next several hours. Meanwhile, over the northern and western Piedmont where clearing is beginning to occur, visibilities are already lowering to MVFR and even IFR in some spots, as the high clouds streaming across central NC are beginning to shift SE. In fact, across south-central VA, many sites are already reporting 1/4 mile visibilities. This is occurring faster than much of the guidance depicted. These observations in addition to a strong signal in the high-res guidance including the HRRR, RAP, and GLAMP mean there is fairly high confidence in widespread dense fog and LIFR conditions developing across all of central NC from NW to SE from around 03z through the overnight hours. Patchy freezing fog will even be possible as low temperatures drop below freezing across much of the region. The fog will then begin to lift and disperse by mid to late morning, with VFR conditions expected everywhere by early afternoon. Winds will be very light to calm tonight, remaining less than 5 kts during the day tomorrow, as high pressure moves overhead.

Outlook: A clipper system will induce a light rain/snow mix that may change to light snow, especially across northern areas, on Monday afternoon. Associated sub-VFR ceilings and visibilities are likely with this as well. VFR conditions will then persist from Monday night through early Thursday. Another weather system will move into the region late Thursday beginning another round of sub-VFR conditions.

RAH WATCHES/WARNINGS/ADVISORIES

None.