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

- Scattered afternoon and early evening thunderstorms today. Main impact area is south of I-10. - Heat Indices of up to 107 this afternoon - High Rip Current Risk and Rough Surf Tuesday through Thursday. Breezy Onshore winds will overspread coastal locations on Tuesday, with gusts at area beaches to 35 mph. - Small Craft Advisory expected to begin Tuesday, continues into Thursday. Waves of showers and storms likely Tuesday, Thursday, and Friday.

NEAR TERM /TODAY THROUGH TONIGHT/

Main Highlights This Period:

- Highest Thunderstorm Chances South of I-95 Corridor, Mainly North Central Florida

- Heat Index Near Heat Advisory Today

Prevailing flow will transition into a more onshore flow pattern today with surface winds shifting to become more out of the northeast and east during the late evening and overnight hours. Drier air associated with high pressure to the north will settle across southeast Georgia today and then advance southward into northeast Florida later tonight, with the dissipating coastal trough being moved westward into the gulf. Convection will be inhibited over southeast Georgia today with the highest likelihood for showers and storms occurring over north central Florida and for areas along and south of the I-10 corridor. High temperatures this afternoon will reach up into the lower to mid 90s over inland areas and in the upper 80s and lower 90s along the coast. Overnight low temperatures will drop down into the the lower to mid 70s for inland areas and in the upper 70s for coastal areas and along the St Johns River. Heat index values for this afternoon will rise to over 105-107 for portions of northeast Florida, however heat advisory levels are not expected to occur prior to the development of diurnal convection.

SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/

Main Highlights This Period:

- A high rip current risk and rough surf likely for area beaches starting Tuesday and last through at least Thursday.

- Breezy northeast winds begins Tuesday, continues through Thursday. A wind advisory is possible for the immediate coast Tuesday and Wednesday.

A backdoor cold front will push through the area Tuesday as strong high pressure builds to the northeast. A surge of northeast and east winds will move south over the region. Strongest winds will be for the coastal counties with speeds up to 15-25 mph, and 10-15 mph well inland. A wind advisory is possible for the immediate coast due to the breezy winds. A chance of showers and embedded storms expected Tuesday due to low level convergence and ample moisture. Best rain chances will be for the coastal areas at 50-60 percent and about 20 percent for the far western zones. Some chance for a few showers will exist Tuesday night into Wednesday morning especially for the coast, but overall a drier airmass will filter into the area with PWATs dropping to about 1.1 to 1.6 inches.

For Wednesday, strong 500 mb high pressure system remains over eastern TN, but retrogrades as a well-deined mid to upper level low over the western Atlantic moves to the north Bahamas late Wednesday. This will continue to enhance the low level pressure gradient continuing the breezy northeast winds over the area with a more stable airmass in place. A small chance of showers (about 10-20 percent) will continue due to the breezy flow off the warm Atlantic waters, but thunder chances are sub 15 percent. For wind headlines, a wind advisory will be possible for the immediate coast.

Temperatures will be above normal by 1-3 degrees Tuesday, but trend lower to about average levels on Wednesday. For lows Tuesday night, a cooling trend is noted with lows in the upper 60s for inland southeast GA, but 70s most everywhere else. Lows trend a bit cooler Wednesday night with the mid to upper 60s for inland areas from I-10 northward and mostly lower to mid 70s elsewhere.

LONG TERM /THURSDAY THROUGH SUNDAY/

Main Highlights This Period:

- Daily chances for showers and thunderstorms - Elevated rip current risk and rough surf for area beaches will continue this period

The mid to upper level low pressure/TUTT feature noted earlier will be passing over the FL peninsula on Thursday while the strong mid level high pressure ridge is situated across mid MS valley to the TN valley. The TUTT feature will likely enhance rain chances, due to increased moisture and instability, from Thursday onward, as the TUTT feature shifts westward, ending up in the central Gulf by Saturday. As the TUTT feature moves away for the weekend, low to mid level high pressure will ease off the Carolina coast and into the western Atlantic this weekend.

For Thursday, still breezy for coastal areas, and good rain chances for the coastal zones and as well as inland northeast FL. For Friday into the weekend, rain chances increase to scattered to possibly numerous coverage for most counties with less of a pressure gradient resulting in weaker surface winds generally from the east and at times southeast as the sfc high pressure moves off to the northeast to east of the area.

Temperatures will trend around average this period.

AVIATION /06Z MONDAY THROUGH 06Z TUESDAY/

VFR conditions overnight and into Monday morning with a potential for MVFR visibilities at KJAX, KVQQ, and KGNV with a potential for lower cloud decks at sites by around sunrise. Worst restrictions will be at KVQQ. Easterly and southeasterly winds will build in for coastal sites and the Jax Metro area in the afternoon with winds being more mild and variable for inland areas. Convection expected to start building by around 16-18z with better chances for showers and storms over northeast Florida.

MARINE

Offshore winds will continue across area waters today with the exception of sea breeze winds building towards the southeast and south during the afternoon hours. Less thunderstorm activity is expected for today and will likely be limited to northeast Florida nearshore waters. From Tuesday through Thursday, a strong northeast wind surge will bring small craft advisory conditions, rough seas, and numerous showers and a few thunderstorms over the area waters. Improving conditions are expected by Friday as onshore winds weaken and seas gradually lower.

Rip Currents: Prevailing offshore winds (excepting for the afternoon sea breeze) and weak easterly swells will keep a low-end moderate risk of rip currents in effect for today. By Tuesday, strengthening northeast winds and building surf combine to lead to dangerous surf and a high rip current risk area beaches starting for Tuesday, and through at least Thursday.

FIRE WEATHER

...Patchy to areas of high dispersions Tuesday through Thursday afternoons...

Weak troughing over the area will dissipate today. Strong high pressure will build to the the northeast as a backdoor cool front moves through on Tuesday. Strong high pressure remains north of the area Wednesday into Thursday. Much higher winds begin by midday Tuesday for the coastal areas with speeds up to 15 to 20 mph, gusting to 30-35 mph. These elevated winds remain in place for Wednesday and possibly into Thursday, especially at the coast. The high pressure north of the area will weaken Friday, with another high building to the northeast over the weekend. Strong surface and transport winds will lead to areas of high daytime dispersion for the Tuesday to Thursday time frame.

A chance of showers and thunderstorms today, mainly inland inland northeast Florida. Higher chances of showers and a few embedded thunderstorms for coastal zones Tuesday.

Fog Potential...Patchy fog is expected early this morning mainly across inland northeast FL. Some patchy fog is possible late tonight/early Tuesday morning inland areas.

PRELIMINARY POINT TEMPS/POPS

AMG 94 73 91 69 / 10 0 30 0 SSI 92 79 88 76 / 10 0 50 10 JAX 92 75 90 73 / 30 0 50 20 SGJ 90 77 88 76 / 20 20 60 40 GNV 93 73 91 73 / 50 20 50 0 OCF 93 74 92 74 / 70 20 60 0

JAX WATCHES/WARNINGS/ADVISORIES

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