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

- Isolated thunderstorms this afternoon for North Central FL.

- Increasing thunderstorm coverage this weekend and into next with isolated strong thunderstorms possible.

- Moderate Rip Current Risk at All Area Beaches

NEAR TERM /THROUGH TONIGHT/

Main Highlights through Tonight:

- Moderate Rip Current Risk at All Area Beaches

- Isolated Storms this Afternoon for North Central FL

Sufficient moisture and cold temps aloft owing to a broad upper tropospheric trough situated off the eastern FL coast will lead to scattered showers and isolated thunderstorms across north central FL this afternoon. Conversely, subsident and drier air across inland southeast GA and the Suwannee Valley will limit shower or convective development. For thunderstorm occurrence today, the zone that will be at highest risk will be primarily along and south of line from Gainesville to Jacksonville.

Beneath the pool of cold air aloft, diurnal heating should promote modest to strong destabilization (MUCAPE 2,500-3,000 J/kg) and spawn widely scattered showers and a few isolated thunderstorms (~20%) through the afternoon. Though thermodynamics will be favorable, there will be a "tug of war" between buoyant updrafts and broader subsident air beneath convergent northeasterly flow aloft, actively suppressing ascent. If a strong enough updraft can overcome and realize available energy, the primary threat will be lightning followed by a secondary threat of gusty outflow winds.

Outside of the limited convective potential today, a breezy onshore flow will keep the coastal areas cooler with highs in the upper 80s while inland highs push into the low 90s amid a drier airmass and dewpoints in the mid 60s.

For tonight, the aforementioned upper trough will retrograde across the Florida Peninsula. As it does, surface onshore flow will weaken decreasing coastal convergence and potential for nocturnal coast showers. Partly clear skies will let temperatures fall to the low 70s inland while the warming onshore flow limits cooling near the coast to the mid and upper 70s.

SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/

Main Highlights This Period: (Saturday through Sunday night)

- Scattered to possibly numerous showers and storms This Weekend, with the greatest chances Sunday

Surface high pressure will be centered to the northeast Saturday and Saturday night. The high will weaken Sunday into Sunday night, as a trough develops to the northwest. An upper low centered over the eastern Gulf will provide added instability this period.

Precipitation chances will be limited somewhat by the surface ridging Saturday. With the influence of the high dissipating Sunday, and upper trough in place precipitation chances will be much higher.

Temperatures will trend above average this period.

LONG TERM /MONDAY THROUGH THURSDAY/

Main Highlights This Period: (Monday through Friday)

- Daily chances for showers and thunderstorms with locally heavy rainfall possible

An inverted surface trough will move across the area through Tuesday night. This trough will move offshore Wednesday, then move to the northeast of the area through Thursday, as a high pressure ridge builds down the east coast. High pressure will build to the northwest Thursday night through Friday.

Above average precipitation chances are forecast through Wednesday, then closer to average Thursday and Friday.

Temperatures this period be near to a little average through Wednesday, then near to a little below Thursday and Friday.

AVIATION /18Z FRIDAY THROUGH 18Z SATURDAY/

Spotty showers continue to track southwestward over NE FL, yielding VCSH through the afternoon. There's a very limited chance (<15%) of thunderstorm development at KGNV but confidence is to low to mention at this time. Otherwise, predominant conditions will be VFR with multilayered clouds and lowest bases around 3-4kft. Northeasterly winds prevail at all sites, around 10-15 knots, and will begin to decrease after 22z. VFR conditions persist tonight but coastal airfields may experience brief MVFR ceilings as bouts of stratocumulus push in from the Atlantic. For inland sites, light fog may develop briefly during the early morning hours Saturday as winds trend calm. Increasing chance for TSRA and SHRA at terminals Saturday, particularly along the I-75 corridor, with ENE to E winds around 5-12 knots.

MARINE

A weak trough positioned over the east coast of Florida will continue the potential for scattered showers and possibly an embedded thunderstorm through late this afternoon, mostly for the waters from St. Augustine southward. Winds and seas should remain below Caution levels during the next several days throughout our local waters. Showers and thunderstorms are expected to increase beginning late Saturday night, with activity likely continuing through at least early next week. A stronger high pressure center may build southward later next week, potentially resulting in another round of northeasterly winds across our local waters.

Rip Currents: Breezy onshore winds will keep breakers in the 3-4 foot range at the northeast FL beaches today, while values subside to the 2-3 foot range at the southeast GA beaches. These conditions will generally yield a higher end moderate risk at all area beaches. Northeasterly winds will only gradually subside this weekend and early next week, maintaining a moderate risk at area beaches.

FIRE WEATHER

High pressure will be northeast of the region through the weekend. An inverted through will be over the area early in the week. Thus trough will move to the northeast during the middle of next week, as a high pressure ridge builds down the east coast of the US.

Fog Potential...No significant fog expected. However, patchy fog is possible for inland areas in the early morning hours this weekend.

PRELIMINARY POINT TEMPS/POPS

AMG 93 70 92 71 / 10 10 30 20 SSI 88 75 88 76 / 0 10 10 20 JAX 89 70 90 73 / 10 10 10 10 SGJ 87 76 88 75 / 20 10 20 30 GNV 91 70 91 71 / 20 0 30 0 OCF 92 70 91 70 / 20 0 30 0

JAX WATCHES/WARNINGS/ADVISORIES

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