textproduct: Charleston

WHAT HAS CHANGED

The Aviation Section has been updated for the 12Z TAF issuance.

KEY MESSAGES

- 1) Warm temperatures with isolated to scattered showers and thunderstorms possible during the latter half of the week.

- 2) A cold front could bring increased rain chances late this weekend into early next week.

DISCUSSION

KEY MESSAGE 1: Warm temperatures with isolated to scattered showers and thunderstorms possible during the latter half of the week.

Guidance is in good agreement indicating a strong mid level ridge encompassing the region through late week. At the surface, high pressure will largely prevail although a weak coastal trough or two could make a run for shore. The pattern largely favors limited diurnal convection, but isolated to perhaps scattered showers and thunderstorms could still get going. The threat for severe weather is low given weak shear and instability. Otherwise, temperatures will remain a good 5-10 degrees above early April normals. Highs peak in the low to mid 80s away from the coast, while lows stay seasonally mild.

KEY MESSAGE 2: A cold front could bring increased rain chances late this weekend into early next week.

Mid level ridging will give way to a trough shifting into the eastern U.S. Sunday into Monday. This will bring the next cold front and higher rain chances to the area. However, significant rainfall looks unlikely as latest NBM indicates the probability for >0.50" in 24 hours is only 10-30%, but certainly any rain will be beneficial given the ongoing drought. Notably cooler temperatures will follow fropa.

AVIATION /12Z WEDNESDAY THROUGH SUNDAY/

Remaining MIFG at the terminals is likely to erode by around 12Z this morning. VFR conditions are expected to prevail at CHS/JZI/SAV today and likely through a bulk of tonight. However, latest guidance suggests another night of patchy fog/shallow ground fog developing at all terminals in the 08Z-12Z Thursday timeframe. At this time, have introduced prevailing 6SM MIFG at all terminals tonight, but TEMPO groups for patchy fog could eventually be needed a few hours prior to daybreak Thursday.

Extended Aviation Outlook: TEMPO flight restrictions are possible at CHS/JZI/SAV terminals with daily showers and/or thunderstorms this weekend, and with the arrival of a cold front early next week.

MARINE

Today and Tonight: Atlantic high pressure will dominate the weather pattern across the Southeast, supporting south/southeast winds 10 kt or less and seas generally ranging in the 2-4 ft range by the afternoon. Small Craft Advisories are not expected during this time frame.

Extended Marine: High pressure will persist across the region through late week, supporting winds/seas that remain below Small Craft Advisory conditions for a majority of waters. Subtle coastal troughing could bring a few showers/thunderstorms on Thursday. Conditions should remain below Small Craft Advisory levels through much of the weekend prior to a cold front advancing toward the region. The cold front should advance across the local area early next week, bringing a period of enhanced winds/higher seas. Conditions appear to support solid Small Craft Advisories across a majority of waters early next week.

CHS WATCHES/WARNINGS/ADVISORIES

GA...None. SC...None. MARINE...None.