textproduct: Jacksonville

KEY MESSAGES

For the latest NE FL and SE GA Daily Key Messages please visit: https:/www.weather.gov/media/jax/briefings/nws-jax-briefing.pdf

- Daily Thunderstorm Potential, with localized flooding possible with heavy rainfall

- Moderate Rip Current Risk at All Area Beaches. Increased Rip Current Risk Possible Late Next Week

UPDATE

A few showers still linger over the area, which should clear in the next couple of hours. Weak to calm winds could allow for fog to develop over inland locations which received rainfall earlier this afternoon, clearing by the early dawn hours. Persisting onshore flow will look to steer some offshore showers towards the coast by the early morning on Monday. The inland push of the Atlantic breeze will push some of the showers towards inland locations during the afternoon, with some storms developing closer to US-301 and I-75.

Overnight Lows in the lower 70s across inland locations, with mid to upper 70s along the coast.

SHORT TERM /THROUGH TUESDAY NIGHT/

- Daily Thunderstorm Potential - Low Flooding Rain Risk Inland Northeast Florida

During this period, a high pressure system from the surface up to about 700 mb will be centered from east TN to NC, while broad low pressure extends well to the south over the Caribbean. This will continue a prevailing east and southeast low level flow. Models show a narrow upper level trough from coastal SC to north FL on Monday that weakens and drifts west-northwest Monday night, with another upper level trough pushing up from the south late Tuesday. Mean steering flow will remain easterly at about 10 kt or less through the period with PWAT values generally in the 1.9 to 2.3 inch range, highest moisture probably being located over northeast FL. With this regime, morning convection will be focused over the coastal waters that pushes onshore each morning, and then begins to focus further inland behind the sea breeze each afternoon. The I-75 corridor over northeast FL may be a hot spot for convection with heavy rainfall/localized flooding both on Monday afternoon and Tuesday afternoon given that area may have better low level convergence. However, with the PWATs being so high, localized heavy rain/local flooding is possible over inland southeast GA, but the overall heavy rain threat there is lower. Guidance hints at the potential for regenerative convection both days given the wind profile pattern and the Corfidi vectors.

Rain chances should tapper off inland each night around the 10 pm to midnight time frame, then resurrect near the Atlantic coast overnight with easterly flow. Patchy inland late night fog will also be possible each night and into the early morning hours.

Temperatures will be near to slightly above average this period with highs in the upper 80s along the Atlantic coast and parts of the St. Johns River basin to lower 90s inland. Muggy overnight lows will range in the lower to mid 70s, and likely upper 70s at the coast.

LONG TERM /WEDNESDAY THROUGH SUNDAY/

Main Highlights This Period:

- Daily Thunderstorms, Isolated Strong Storms Possible Inland - Increased Rip Current Risk Possible By Mid-Week

The synoptic pattern through the extended forecast does not change much with a surface to mid level ridge staying just to the north of the area maintaining a prevailing easterly flow. For Wednesday, there is a fairly high amount of moisture with GFS showing 70-85 percent mean layer RH over most of the area, which does appear to trend slightly lower for the rest of the extended period. This pattern favors elevated diurnal rain chances, for the area with POPs of at least the 40-60 percent range each day. Highest chances are likely going to be over northeast FL based on latest guidance.

The one other feature that we will monitor is the remnants of Dolly, as a tropical wave moves across the Bahamas mid week, and some associated moisture moving into parts of central and south FL by Wednesday night and Thursday. The latest NHC Tropical Weather Outlook continues to only have a 20 percent of development over the next 7 days for this system. While some indirect impact is possible with additional tropical-like moisture that could move into northeast FL by the weekend, confidence is not high. Additionally, with the continued easterly flow and some relatively weak easterly swells, an elevated rip current risk is expected to continue.

Temperatures will trend slightly above average during the long term period.

AVIATION /00Z MONDAY THROUGH 00Z TUESDAY/

Showers will begin to clear by 01Z/02Z this evening. With lower winds, inland fog could develop and bring lower vsbys for VQQ/GNV around 07Z, lifting by 12Z. With onshore flow persisting, coastal showers will be possible near SSI/SGJ during the early morning hours. Inland push of the Atlantic breeze will bring chances of showers/storms towards inland sites by 16Z/17Z.

MARINE

Onshore flow will continue through the week as an mid level ridge remains north of the local waters. This will allow for offshore showers to push towards the coastal locations each morning, then onshore as the sea breeze pushes inland. Small craft advisories are not expected during the upcoming week.

Rip Currents: A more solid Moderate risk of rip currents rest of today in the onshore flow as surf/breakers are now near 2 to 3 foot range. This pattern will continue into early next week as well with a possible more elevated threat by late Tuesday or Wednesday with additional long period easterly swells of about 13 seconds.

FIRE WEATHER

East to southeast winds will prevail through at least the next several days with high pressure centered to our north. Showers and thunderstorm chances will remain high thanks to the onshore flow, plenty of moisture, and a weak troughs of low pressure. The best chance for strong thunderstorms will be generally towards Highway 301 to I-75 and areas further west. Outside of rainfall, dispersions will be only in the fair range thanks to the onshore flow and weaker winds aloft.

Fog Potential: Gusty and erratic winds can be expected in and near thunderstorms with briefly localized flooding rainfall. Late night and early morning patchy fog and low stratus will be possible, especially in areas that received more rainfall.

PRELIMINARY POINT TEMPS/POPS

AMG 73 91 73 91 / 10 40 20 50 SSI 78 87 78 87 / 20 40 40 50 JAX 74 89 74 90 / 20 30 40 60 SGJ 76 88 75 88 / 20 30 40 50 GNV 73 91 73 90 / 20 60 20 80 OCF 73 91 73 90 / 40 60 20 80

JAX WATCHES/WARNINGS/ADVISORIES

FL...None. GA...None. MARINE...None.