textproduct: Raleigh

WHAT HAS CHANGED

* Timing of the stratus and fog (mainly expected between 08z and 13z).

* NBM continues on the higher extreme for the heat this week, EC ensembles appear more in line. Peak of the heat will likely be through Thursday, with some cooling with better chance of PM thunderstorms by Friday.

* Labor Day weekend trending cooler. Drier, especially Sunday.

DISCUSSION

As of 200 AM Monday...

KEY MESSAGE 1... Low stratus and fog mainly from Raleigh south and east through mid-morning. Hot weather returns with highs around 90 today.

Some patchy fog had already developed in the past hour and additional fog/stratus is expected in most areas by 09z. The exceptions may be the western and northern Piedmont where the low level moisture is not as high.

Areas of dense fog will be possible. A dense fog advisory may be needed in some areas from Raleigh south and east to Goldsboro if fog is expected to become widespread and less than 1/4 mile.

It will be hotter today as the upper ridge expands eastward from the Plains. Mostly sunny skies by late morning through the afternoon will yield highs in the upper 80s to lower 90s.

KEY MESSAGE 2... Peak of the heat will likely be Tuesday through Thursday with highs in the mid to upper 90s, heat indices of 105+ in the climo favored eastern Piedmont south and east to the coast. Some cooling with better chance of PM thunderstorms by Friday.

The strong upper ridging will gradually build east from OK/KS to the TN/NC region by late Thursday. As the surface high shifts offshore, the SW flow will bring high heat and humidity to all the region this week. The guidance is not terribly strong with upper heights as in the early July heat wave in which the H5 heights topped out at 5990m. This one may peak out in the in the 5950m. or about 40m weaker. Regardless, the sun angle is lower, the soil moisture is spotty but wetter, it is visually greener, and the NBM continues to overheat. It will be an early September heat wave, but more tame than the early July heat wave.

Expect mainly sunny hot days and clear, warm nights Tue-Thursday night. Lows in the 70s. Highs in the mid to upper 90s. Heat indices of 105-109 from Raleigh south and eastward Wednesday and Thursday (when this heat wave peaks for us).

By Friday, a disturbance in the NW flow should beat down the upper ridge from the Great Lakes into the Mid-Atlantic states late in the day through Saturday. Highs Friday (lower to mid 90s) with a chance of PM thunderstorms.

KEY MESSAGE 3... Labor Day weekend will be cooler with a lingering chance of showers/storms south and east Saturday. Sunday and Labor Day should be mostly dry with highs in the 80s.

The mid/upper heights fall Friday and Saturday, with a surface front likely to push south and east to near the Coast Saturday. The better chances of storms should push to the south and east of the Triangle Saturday. Sunday and Labor Day have been trending drier and cooler. Expect highs in the 80s. Lows in the 60s to near 70 SE.

AVIATION /12Z MONDAY THROUGH FRIDAY/

As of 645 AM Monday...

Through 12Z Tuesday: Fog is possible through 14z, especially around KRWI and KFAY. Confidence in fog is lower at RDU, GSO, and INT where model guidance keeps skies clear and only shallow ground fog is expected.

VFR is then expected areawide by mid-morning through much of tonight. There is a chance of stratus and fog again around KRWI and KFAY early Tuesday.

Outlook: Generally VFR conditions are expected into Friday. The chance of showers/storms should return by Friday afternoon and linger in the east on Saturday.

CLIMATE

Record High Temperatures:

September 2: KRDU: 99/1912

September 3: KRDU: 99/2010 KFAY: 101/2010

September 4: KRDU: 100/1925 KFAY: 100/1944

Record High Minimum Temperatures:

September 2: KGSO: 73/1912 KRDU: 75/1912 KFAY: 75/2020

September 3: KGSO: 73/2020 KRDU: 78/1933 KFAY: 77/2020

September 4: KGSO: 72/2018 KRDU: 74/1921 KFAY: 75/2020

RAH WATCHES/WARNINGS/ADVISORIES

None.