textproduct: Raleigh

WHAT HAS CHANGED

As of 125 AM Monday...

* Added the potential for dense fog tonight into Tuesday morning.

KEY MESSAGES

As of 125 AM Monday...

1) Rain coming to an end this morning, with patchy fog early and then a slow scattering of clouds through this evening. Radiational fog appears likely late tonight through early Tuesday. Locally dense fog may be possible.

2) Temperatures climbing above normal Tuesday through Saturday with quiet weather becoming unsettling Thursday through the weekend.

DISCUSSION

As of 125 AM Monday...

KEY MESSAGE 1... Rain coming to an end this morning, with patchy fog early and then a slow scattering of clouds through this evening. Radiational fog appears likely late tonight through early Tuesday. Locally dense fog may be possible.

The stout shortwave and occluded surface low crossing GA/SC will continue east this morning, with precip north of the low expected to collapse southeast across the area and quickly come to an end. Without a true surface cold frontal passage from the northwest, cloud cover east of the Triad will linger through the the afternoon/early evening before drier air arriving from the west can be mixed down today. The Triad will likely scatter out earlier. Thus temps are expected to be warmest in the west, ranging from lower 50s east to lower 60s west. With the onset of mixing, forecast soundings suggest a little gustiness, perhaps to 20-25 mph in the Piedmont/Coastal Plain where clearing and stronger lower-level winds coincide.

Given little air mass change and saturated soils combined with light to calm winds tonight will likely result in radiation fog. Areas of dense fog may be possible from ~09Z through ~14Z, especially for locations along and west of US-1 (HREF probabilities for <0.25 miles peak around 60 to 70% in this vicinity during that temporal period). Confidence in the areal coverage of dense fog further east is lower as it's not quite clear how much lingering cloudiness will see out there later today into the overnight period.

KEY MESSAGE 2... Temperatures climbing above normal Tuesday through Saturday with quiet weather becoming unsettling Thursday through the weekend.

The sub-tropical; ridge will build east across the Gulf this week, resulting in rising heights and warming across the Southeast. Low- level thicknesses are forecast to rise above 1370m by Friday which supports highs warming well into the 70s for much of the area. A series of shortwaves traversing the top of the ridge causes the mean frontal zone over the Mid-Atlantic region to sink south and result in some showers Thursday into Friday. Confidence for the next chance of rain is higher over the weekend as a shortwave and cold front are expected to move across our region. Even then there is still a wide spread in ensemble guidance for timing. Cloud cover associated with these shortwaves could create some uncertainty in the high temperature forecasts late week and into the weekend. The warmest day is expected to be Friday with high temperatures in the upper 60s north to upper 70s to near 80 across the south. After the cold front passes through Sunday, highs on Monday are expected to be slightly below normal ranging from the mid/upper 40s near 50.

AVIATION /12Z MONDAY THROUGH FRIDAY/

As of 630 AM Monday...

12Z Update: KINT/KGSO have cleared out the past several hours and should maintain VFR conditions through late tonight. Still don't have the highest confidence in when ceilings might scatter at KRDU and KFAY, but best chances would be late this afternoon/early evening. KRWI may keep a sub-VFR ceiling into the overnight hours. The fog forecast is a bit difficult as well, as latest high-res guidance has trended towards maybe denser cloud cover tonight at KRDU/KFAY than previous guidance suggested. As of now, think the best chances for significantly reduced visibilities due to dense fog remains at KINT/KGSO. Although, patchy fog may be possible at all terminals.

Previous discussion:

The last of the light to moderate rain is currently pushing through KFAY/KRWI early this morning. Expect any lingering rain to pretty much wrap up by ~10Z. We'll continue to remain socked in this morning before lifting the MVFR/VFR at KINT/KGSO near sunrise (possibly earlier). Further east, improvement to MVFR/VFR should be slower as low-level moisture lingerings into the late afternoon. The RAP even keeps KRDU/KFAY/KRWI sub-VFR through the end of the 24 hr TAF period. However, this is an outlier, with most guidance lifting these sites to VFR by ~20 to 23Z.

Expect nnwly gustiness to persist through sunrise, especially for sites further east. Sfc winds will turn more nnely Monday with gusts of up to 25 kts possible at KRWI/KFAY through early to mid afternoon before subsiding through the evening hours.

Outlook: VFR conditions are expected Tues through at least Wed night. Southwest winds will become gusty on Wed when widespread 25 to 30 kt gusts are expected.

RAH WATCHES/WARNINGS/ADVISORIES

None.