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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

- Flood Watch Through This Evening for Inland Southeast GA. Mainly for areas from Waycross Northward. Areas that received heavy rain Friday will be prone to flooding today.

- Numerous to Widespread T'storms This Afternoon and Evening. Main Hazards Wind gusts to 50 mph, frequent lightning, locally heavy rainfall

- Hot and Humid Conditions Continue into Next Week. Heat Index Values 103 to 107 degrees Today and Sunday for Northeast FL. Dangerous Heat Index Values of 105 to 110 degrees Possible Next Week.

NEAR TERM /THROUGH TONIGHT/

Main Highlights Today and Tonight:

- Numerous to Widespread Showers and T'storms Today - Potential for Flooding across portions of inland Southeast GA

A frontal boundary just north of the Altamaha river basin will begin to slow as it moves into SE GA mid to late morning. Ahead of the front, warm and moist air is in place with current temps a little cooler compared to 24 hours ago in the low 70s along and north of I- 10 and mid 70s over north central FL and the coast due to strong outflows from yesterday's T'storms bringing slightly cooler air to the surface. Mid to high level cloud cover will remain as high moisture content and westerly flow aloft carries clouds downstream of storms along the central Gulf coast. A few showers will press in from the NE Gulf towards I-75 by sunrise with very light winds 3-6 mph through mid morning.

Today, the base of a broad mid/upper level trough will move east off of the Carolina coast with mid level ridging over the central Gulf of America waters. Unstable shortwave energy will funnel across the Gulf coast/deep south into the area between these two features and move above a surface frontal boundary sinking from SE GA towards the FL/GA state line. Light WSW winds and low level flow will keep high moisture levels (PWATs around 2.00 inches) over the area ahead of the front and keep our skies mostly cloudy. The clouds will limit some of the low level heating, but mid level temperatures around -8C will allow for mid level lapse rates near 6.0 C/km, more supportive of strong updrafts.

This instability along with lift along the front and shortwave energy passing aloft will help spur numerous to widespread T'storms by the early afternoon. Activity will begin as a wave of showers pushes eastward from the Suwannee Valley eastward and generate increasing coverage of T'storms from I-75 to the Atlantic coast. Gusty winds of 40 to 50 mph, frequent lightning, and locally downpours will be the main hazards with locally heavy rainfall totals of 2-3 inches. Additional showers will linger after T'storms push off the Atlantic coast late this afternoon through sunset and end between 10PM and midnight.

A Flood Watch is in effect for inland Southeast GA through tonight where 4-10 inch rainfall totals occurred Friday and T'storms generating heavy rainfall rates of 2-3 inches per hour could exacerbate flood potential along and north of US-82.

The clouds will mute today's highs to the upper 80s for most inland areas, and around 90 closer to the I-95 corridor and across north central FL. Westerly winds 5-10 mph will turn west to WNW later this afternoon. Tonight, slightly drier air aloft will arrive late as a weak low level ridging moves over the region and the weakening front settles near north central FL. Skies will become partly cloudy and lows will fall to the low 70s.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/

Main Highlights This Period:

- Lower rainfall coverage expected on Sunday - Heat Advisory conditions expected on Monday

Sunday: Frontal boundary lifts north of the region and temps will build back to above normal levels with highs in the lower 90s. Some lingering moisture in the Westerly steering flow will still support at least scattered afternoon storms, with focus towards the Atlantic coast along the I-95/US-17 corridors. Isolated strong/severe storms possible, along with locally heavy rainfall. Heat Indices will peak around 105F, but will likely remain below Advisory criteria.

Monday: High pressure will build into the region at the surface and aloft and with only isolated afternoon storms expected in the westerly steering flow, expect Max Temps to reach into the middle 90s and peak heat indices into the 105-110F range, likely enough to support Heat Advisory conditions for all of NE FL and coastal SE GA.

LONG TERM /TUESDAY THROUGH FRIDAY/

Main Highlights This Period:

- Heat Advisory conditions expected Tuesday and Wednesday - Return to at least scattered afternoon storms mid to late week

Tue/Wed: High pressure ridge at the surface and aloft will keep storm chances only isolated on Tuesday and widely scattered on Wednesday, which under Westerly flow will still support max temps above normal and into the middle 90s, and expect heat indices into the 105-110F range, with Heat Advisory conditions expected for most of NE FL and coastal SE GA.

Thu/Fri/Sat: Still remaining hot and humid with Max Temps into the lower to middle 90s, but frontal boundary is expected to drift into the SE US and break down ridge of high pressure enough to support scattered to numerous afternoon storms, as more deeper moisture is injected into the region aloft. Daily heat indices will still top out at least as high as 105F, and will approach Heat Advisory criteria, but confidence is a bit lower for Heat Advisory headlines later in this time frame. The expected Westerly flow will continue to focus daily afternoon storm activity closer to the Atlantic Coast and along the I-95/US-17 corridor, with isolated strong/severe storms possible each day.

AVIATION /06Z SATURDAY THROUGH 06Z SUNDAY/

VFR conditions will become MVFR after 08Z as low stratus develops inland and shifts to the coast through sunrise west southwest winds around 5 knots becoming variable inland.

The next round of showers will be just after sunrise near GNV and shift east to east southeast near or south of SGJ. Additional rounds of showers will develop after 15Z Saturday as waves of energy aloft and the approaching front from the north combine to create increasing coverage of T'storms into the afternoon hours. Have kept PROB30 groups for MVFR/IFR ceilings and visibility levels in T'storms a bit sooner at GNV further west around 16Z, and a bit later at the coastal and Duval county terminals around 18Z. Strong wind gusts potential to 25 knots also included for gusty, erratic winds in T'storms. Winds will become more westerly outside of T'storms 6-10 knots.

T'storms will end and move off the Atlantic coast after 23Z with showers fading by 02Z with broken MVFR ceilings scattering before the end of the period as slightly drier air arrives. Winds will diminish to near calm after 02Z.

MARINE

A frontal boundary will move south into the area waters today bringing additional rounds of thunderstorms. The front will weaken near the Northeast FL waters on Sunday with isolated Thunderstorms in the afternoon. Weak high pressure ridge will slowly build in over the area waters early Monday and into Tuesday with isolated to scattered Thunderstorms returning by midweek as another front moves in from the north. WInds will turn southerly in the afternoon hours due to the daily seabreeze circulation next week.

Rip Currents:

Generally a low risk of rips expected into the weekend as surf remains in the 1-2 ft range with offshore flow continuing.

FIRE WEATHER

The front will move into the area Today as widespread showers and T'storms will once again be possible. As the front lifts north as a warm front on Sunday, drier air will filter into the region as ridging builds across the FL peninsula. Scattered showers and isolated T'storms expected on Sunday and through midweek.

Good level dispersions expected during each afternoon through the weekend as more clouds limit mixing heights, with higher dispersions expected by Monday.

High humidity levels continue this weekend. Temperatures will rise next week with drier conditions and limited chances for T'storms with potential heat advisory conditions Monday and Tuesday.

FOG POTENTIAL AND OTHER REMARKS: Areas that receive heavier rainfall may also experience patchy late-night and early-morning fog. T'storms will produce locally gusty winds, frequent lightning, and locally heavy downpours.

EQUIPMENT

The WSR-88D Radar located near the Moody AFB near Valdosta remains offline due to technical problems. Technicians are awaiting critical parts to restore functionality. During the outage please utilize other area radars...KJAX, KTLH, or KJGX.

PRELIMINARY POINT TEMPS/POPS

AMG 88 71 91 73 / 90 30 20 10 SSI 90 75 88 77 / 60 40 20 10 JAX 90 73 91 74 / 80 50 30 10 SGJ 90 74 91 75 / 70 40 40 10 GNV 90 73 92 73 / 80 30 40 0 OCF 91 75 92 73 / 70 20 40 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...None. GA...Flood Watch through this evening for GAZ132>136-149-151-152- 250. MARINE...None.