Marine Weather and Tide Forecast for Rocky Mount, NC

KEY MESSAGES
As of 315 PM Saturday...

1) A few isolated showers possible this afternoon and evening.
Patchy fog possible overnight into early Sunday. Mostly dry through Sunday night.

2) A pair of cold fronts will bring a chance of showers, the first Sunday night into Monday and the second on Wednesday and Wednesday night. Overall amounts and impacts should be low.

DISCUSSION
As of 315 PM Saturday...

KEY MESSAGE 1... A few isolated showers possible this afternoon and evening. Patchy fog possible overnight into early Sunday. Mostly dry through Sunday night.

A few isolated showers continue to move across the southern Coastal Plain this afternoon driven by 925 mb WAA/isentropic upglide. The 925 mb WAA maxima has largely shifted towards the coastal areas as the base of the mid-level trough moves over central NC. As such, think this isolated activity in the south should largely fizzle out the next few hours. Further upstream over the VA/NC high terrain and foothills, clearing has led to some weak SBCAPE. While largely void of sfc or upper lift, can't rule out a few isolated showers trickling into the Triad late today. Otherwise, expect dry conditions overnight and into majority of Sunday. Latest guidance shows perhaps some late convection trickling across the NC/VA border Sunday night, but largely holds off on any widespread rain until after 12Z Sunday.

While clouds will hang around for much of tonight, some pooling of low-level moisture could result in patchy fog especially for those along and east of US-1.

KEY MESSAGE 2... A pair of cold fronts will bring a chance of showers, the first Sunday night into Monday and the second on Wednesday and Wednesday night. Overall amounts and impacts should be low.

A cold front will approach the region from the NW on Sunday night as a mid/upper trough brings weak mid-level height falls to the southern Mid-Atlantic. This will result in increased shower chances, especially on Monday morning and afternoon when POPs are high chance to likely. The greatest amounts should be in SE parts of the area where moisture and instability will be most favorable. But even there, QPF is only in the quarter to half inch range at most. Very light amounts of a tenth of an inch or less are expected across the Piedmont.

Isolated storms will be possible in the south and east along and ahead of the front, but this will depend on the timing of its passage. A slower passage, like what is depicted on the ECMWF and NAM, will give more time for daytime heating and instability to develop, while the faster GFS keeps the instability axis largely to our south. Ahead of the front, 500-1000 J/kg of SBCAPE will be possible, along with steep low-level lapse rates and 45-55 kts of bulk shear. So isolated damaging winds can't be ruled out there, and the Day 3 marginal risk of severe weather from SPC clips southern Sampson County. Any rain chances will end on Monday night.

Temperatures will be slightly below normal for the remainder of the workweek. Tuesday will be the coolest day, with highs in the upper- 60s to lower-70s and lows in the upper-40s to lower-50s. Highs will be in the mid-to-upper-70s from Wednesday through Friday. A weak cold front may bring another chance of showers on Wednesday and Wednesday night, but ensemble mean QPF is only a tenth to a quarter inch, and impacts should be minimal. Warm weather will return on Saturday with forecast highs in the mid-80s.

AVIATION /23Z SATURDAY THROUGH THURSDAY/
As of 650 PM Saturday...

TAF period: High confidence in VFR conditions for the next 24 hours at INT/GSO, less confidence of that at RDU/FAY/RWI. While high ceilings are present at all terminals, mid level cloudiness is a bit greater at sites farther south and to the east. While numerical guidance is showing the potential for visibility restrictions at FAY/RWI, think that the combination of mid and high level cloudiness at these sites could limit the overall fog potential. Cannot rule out the potential for fog at RDU, but also don't have enough confidence to add any restrictions there. At FAY/RWI, the 00Z TAFs will be slightly more optimistic than the 18Z TAFs with the tempo group. Light southwest wind overnight will veer to the northwest Sunday morning with clearing clouds, then the wind will likely back to the southwest again Sunday afternoon.

Outlook: A cold front and area of low pressure will bring showers and some storms Monday, most favored at RDU/FAY/RWI. High pressure brings VFR conditions Tue. Another frontal system will bring a threat of sub-VFR showers Wed into Thu.

RAH WATCHES/WARNINGS/ADVISORIES
None.