Marine Weather and Tide Forecast for Rocky Mount, NC

KEY MESSAGES
As of 130 AM Monday...

1) Scattered to numerous showers and thunderstorms with very heavy rainfall will continue be possible today and Tuesday, and could result in an isolated flooding threat.

2) Mainly diurnally driven showers and storms expected from Wednesday into next weekend.



DISCUSSION
As of 130 AM Monday...

KEY MESSAGE 1... Scattered to numerous showers and thunderstorms with very heavy rainfall will continue be possible today and Tuesday, and could result in an isolated flooding threat.

Central NC remains situated between a weak upper-level low that has settled near the Southern Appalachians and the sub-tropical ridge off the East Coast, with moist southwesterly flow, precipitable water (PW) values near or above two inches, and muggy dew points in the mid-to-upper 70s. Similar to today, weak diffluence aloft and subtle perturbations in the southwesterly flow should support scattered to, at times, numerous showers and isolated thunderstorms from late this morning through this evening. Most guidance suggests activity will be focused near or east of I-95 in the deep moisture axis, or along a cold front/convergence zone shifting east into the Piedmont as the upper low moves across northern Georgia. Activity should increase with peak heating, as elevated dew points support the redevelopment of 500-1000 MLCAPE, despite weak lapse rates aloft. Rainfall rates of 1-2 inches per hour and the potential for training could lead to isolated flooding, but overall QPF and confidence in any specific area remain too low to warrant a Flood Watch, despite the generally favorable pattern.

On Tuesday, the upper low is expected to wobble slightly back to the northwest, and a more southeasterly flow will likely bring a surge of moisture with PW values exceeding 2 inches back across the Piedmont. Deep-layer steering flow is rather weak, and mbE velocity is also very low on the northeast side of the low. Consequently, there may be a slightly higher risk of flooding given the potential for greater coverage of showers and storms, combined with their slow movement.

KEY MESSAGE 2... Mainly diurnally driven showers and storms expected from Wednesday into next weekend.

The upper low over the Southeast U.S. is forecast to drift northward and be absorbed by a trough crossing the Great Lakes by the end of the week. With the Bermuda High remaining in place, a moist environment will persist over central North Carolina, though with decreased forcing outside of diurnal influences such as differential heating, sea breezes, and other boundaries, especially toward the end of the week. it will remain warm and muggy, with highs in the 80s and dew points in the 70s, resulting in weak instability each day and isolated to scattered afternoon showers and storms.

AVIATION /12Z MONDAY THROUGH FRIDAY/
As of 650 AM Monday...

12Z TAF Period: Light showers are moving across eastern NC Expect ceilings to be IFR/LIFR in the NW and MVFR in the east for a few hours this morning before lifting to VFR. Late afternoon showers and storms will be primarily across the south and east. Overnight will be similar to this morning with widespread MVFR (and below) ceilings through most of Tuesday morning.

Outlook: Afternoon heating on Monday and Tuesday will trigger another round of scattered showers and thunderstorms with localized sub-VFR conditions. Pre-dawn IFR/LIFR stratus and fog restrictions remain likely each night, particularly over areas that receive heavy rainfall during the afternoon. Coverage tapers back toward typical summer-like isolated/scattered convection Thursday into Friday.



RAH WATCHES/WARNINGS/ADVISORIES
None.