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

- Dangerous Heat Indices Continue this Weekend. Heat Advisory this Afternoon through Early this Evening for Northeast & North

- Central FL & Portions of Southeast GA. High Temperatures this Weekend : 94- 99. Peak Afternoon Heat Index Values Saturday and Sunday: 105- 110

- Strong to Isolated Severe Storms Possible Late this Afternoon. Hazards: Damaging Wind Gusts of 40-60 mph, Frequent Lightning & Small Hail

- Increasing Coverage of Afternoon & Evening Thunderstorms Sun Tues. Strong to Isolated Severe Storms Possible Each Day. Heavy Downpours and Localized Flooding Possible

NEAR TERM /THROUGH TONIGHT/

Main Highlights Today and Tonight:

- Heat Advisory conditions for much of the forecast area

- Afternoon thunderstorms, which may become strong to severe

A ridge of high pressure will stretch across southern FL through Tonight. The east coast sea breeze will move inland this afternoon, making it to around the I95 corridor. Convection will develop this afternoon, with scattered to numerous coverage.

Temperatures will be above normal this afternoon. Heat index values will be in the advisory range for all of NE FL, and for SE GA near the GA/FL border. Temperatures will remain above normal Tonight, with lows in the middle 70s.

SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/

Main Highlights During This Period:

- Increased Storm Chances Sunday and Monday - Heat Advisories still possible, mainly across Northeast Florida

Southwest steering flow off the Gulf coupled with an approaching front from the north will increase moisture across the area Sunday and Monday, prompting higher convective chances then we've seen this past week. Westerly surface winds will allow the Gulf sea breeze to push far inland, reaching the Atlantic sea breeze closer to I-95, leaving higher strong storm potential in that region as well as closer to the front across southeast Georgia. Still going to be pretty hot on Sunday, with highs in the mid to upper 90s, with the hottest apparent temperatures near the east coast, where values will approach Heat Advisory criteria.

Monday, shower and storm coverage increases further as the aforementioned front sinks further south into central Georgia. Highest storm chances will again be closer to the front, along and north of I-10, and also along the northeast Florida coast where the sea breezes interact. The primary strong storm threats will be gusty winds and heavy rainfall potentially causing flooding concerns. Again, convection may linger past sunset across southeast Georgia mainly. Temperatures will lower a few degrees Monday, with highs in the lower to mid 90s.

Isolated storms may linger after sunset both Sunday and Monday nights closer to where the front is, over southeast Georgia.

LONG TERM /TUESDAY THROUGH SATURDAY/

Main Highlights During This Period:

- High storm chances continue Tuesday - Heat re-builds into the region Wednesday through Friday

Numerous showers and storms are forecast again for Tuesday as the front sits across South Georgia, then slowly dissipates through the rest of the week. Most of the area is under a 'Marginal' risk of Excessive Rainfall on Tuesday, after several days of heavy rain there will be a threat of localized flooding, especially near the front and over flood prone areas.

Storm chances are generally lower Wednesday onward as northwesterly steering flow brings in drier air aloft, precipitation chances will be around 20-40%. Temperatures will gradually rise again each day through Friday back into the mid to upper 90s, with a risk of Heat Advisory headlines once again, mainly across Northeast Florida.

AVIATION /18Z SATURDAY THROUGH 18Z SUNDAY/

Scattered to numerous thunderstorms are expected to develop this afternoon, with restrictions and gusty winds in and near these storms.

Thunderstorm activity is expected to dissipate by midnight, with prevailing VFR conditions overnight.

Convection is expected to get a little earlier start Sunday, with activity reaching KGNV late morning.

MARINE

The region will be between high pressure to the south, and frontal zone just to the north through the middle of next week.

Rip Currents:

Southeasterly winds strengthening late this afternoon will create a lower end moderate risk at the northeast FL beaches, with surf increasing to around 2 feet towards sunset. Lower surf of only 1-2 feet at the southeast GA beaches should yield a low risk throughout the weekend and early next week. Surf heights of less than 2 feet at the northeast FL beaches on Sunday and early next week should also yield a low risk.

FIRE WEATHER

- Areas Of High Dispersions Today And Tuesday North Of I-10

Drier than normal conditions are forecast through this afternoon before rain chances begin to increase Sunday and into early next week as a frontal boundary approaches from the north. Southwesterly surface winds continue through early next week, with areas of high afternoon dispersion along and north of I-10. Despite drier air in place, minRH will remain just above critical values, in the 30 to 40% range away from the coast this afternoon, but will return to more seasonable MinRh values of 40 to 50% Sunday into next week. Heavy rain potential Sunday through Tuesday due to expected numerous showers and storms each afternoon and evening.

Fog Potential and other remarks: Significant fog potential is not expected. Erratic wind gusts possible in and near thunderstorms, and at times, at a distance due to outflows.

CLIMATE

Daily record high temperatures at our designated climate sites for this weekend, July 11th-12th.

July 11th: KJAX: 104/1879 KGNV: 100/1900 KAMG: 100/1980 KCRG: 99/1998

July 12th: KJAX: 102/1879 KGNV: 99/1902 KAMG: 102/1966 KCRG: 99/2015

PRELIMINARY POINT TEMPS/POPS

AMG 75 96 74 92 / 10 40 60 80 SSI 79 97 78 93 / 30 40 40 80 JAX 76 97 76 95 / 30 60 40 80 SGJ 77 95 77 94 / 20 60 20 80 GNV 74 95 75 94 / 30 40 10 60 OCF 74 94 76 93 / 40 30 10 50

JAX WATCHES/WARNINGS/ADVISORIES

FL...Heat Advisory until 7 PM EDT this evening for FLZ021-023-024- 030-031-035-038-120-124-125-132-136>138-140-220-225-232- 233-236-237-240-322-325-333-340-422-425-433-522-533-633. GA...Heat Advisory until 7 PM EDT this evening for GAZ152>154-162- 163-165-166-264-350-364. MARINE...None.