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

- Heat and Humidity Builds through Early Next Week. Heat Index Values Rise to the 100-105 Range Inland this Afternoon & Friday. Heat Advisory Conditions Possible this Weekend as Values Rise to 105- 110

- Scattered Afternoon & Evening TStorms Inland Today. Heavy Downpours & Frequent Lightning Strikes Possible Across North Central FL

- Moderate Rip Current Risk at All Area Beaches Today

- Afternoon & Evening TStorms Area-Wide this Weekend into Next Week. Strong Storms with Gusty Winds, Frequent Lightning Strikes & Heavy Downpours Possible Along the I-95 Corridor

NEAR TERM /THROUGH TONIGHT/

Main Highlights This Period:

- Scattered showers and thunderstorms this afternoon and evening, mainly for inland locations.

- Heavy downpours and frequent lightning strikes will be possible near the I-75 corridor in north central FL late this afternoon and early this evening.

- Heat index values peak in the 100-105 degree range at inland locations this afternoon as highs climb to the low and mid 90s.

- Moderate rip current risk at all area beaches as breezy onshore winds develop this afternoon.

Scattered showers and storms will develop throughout the forecast area this afternoon and evening with higher likelihoods for convection occurring over north central Florida and extending into northeast Florida for areas west of the I-95 corridor with the most likely threats from storms today being frequent lightning, locally heavy rains, and gusty winds. Prevailing southerly flow will shift to become more out of the west and northwest during the overnight hours and into the following morning as the influence of high pressure ridging from out of the east begins to weaken. High temperatures this afternoon will rise into the mid 90s over inland southeast Georgia and in the lower to mid 90s for northeast Florida, with max temps along the shoreline in the upper 80s and lower 90s. Overnight low temperature tonight will drop down into the lower to mid 70s over inland areas and in the mid to upper 70s along the coastline. Heat index values this afternoon are expected to reach up to about 100 degrees for inland areas.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/

Main Highlights This Period:

- Slight chance for thunderstorms Friday afternoon and evening

- Scattered to numerous thunderstorms Saturday afternoon and evening, a few strong to severe storms possible

- Low to Moderate Risk of Rip Currents

High pressure will move away to the southeast Friday, as a trough digs into the southeastern US. The low level flow will be from the southwest Friday allowing the Gulf sea breeze to push to the east. The east coast sea breeze will push inland to around the I95 corridor in the afternoon. Convective chances will be greatest where the sea breeze intersects, which will be near the I95 corridor. With loss of diurnal heating, this activity will then diminish Friday evening, with a dry night forecast for Friday night.

On Saturday, the high will be further away to the southeast, with the trough just to the east. The flow will will still be from the southwest, but will be lighter than Friday due to high being further away. With the lighter flow, the Gulf sea breeze will not get as far inland before intersecting with the East coast sea breeze. This intersection is expected to occur over the 301 corridor. This is where the greatest chance for convection will be, although chances will exist area wide. Once again, this activity will diminish Saturday evening.

Above normal temperatures are forecast this period.

LONG TERM /SUNDAY THROUGH THURSDAY/

Main Highlights This Period:

- Scattered to numerous afternoon and evening thunderstorms. A few strong to severe thunderstorms possible.

The region will remain between high pressure to the south and trough to the north through Tuesday. Scattered to numerous showers and thunderstorms will be expected Sunday through Tuesday, mainly during the afternoon hours, due to sea breeze interactions and diurnal instability.

The trough will sink across the area as a week front Wednesday into Thursday. Convective chances will increase Wednesday and Thursday, due to convergence associated with the boundary.

Temperatures are expected to trend above average through Tuesday, then near average for Wednesday and Thursday.

AVIATION /18Z THURSDAY THROUGH 18Z FRIDAY/

Showers and thunderstorms will develop along inland moving mesoscale boundaries and advancing sea breezes this afternoon, with activity likely converging and increasing in coverage between the U.S. Highway 301 and Interstate 75 corridors after 20Z. Activity should dissipate by 02Z at GNV, with VFR conditions otherwise prevailing this evening. Winds for inland areas will become more mild and variable by around 06z-08z.

MARINE

Atlantic high pressure centered near Bermuda will weaken and shift southward later today and tonight. A frontal boundary will then enter the southeastern states on Friday night before stalling to the north of our waters during the weekend. Light southerly winds this morning will become onshore early this afternoon as the Atlantic sea breeze shifts inland, with breezy conditions developing by late this afternoon across the near shore waters. Winds will then shift to southerly early this evening and will surge to near Caution speeds throughout our local waters. Unseasonably dry weather will otherwise continue through Saturday. Prevailing winds will become westerly on Friday morning, followed by breezy southeasterly winds developing by late afternoon. Southerly evening wind surges are forecast this weekend. Scattered afternoon and evening showers and thunderstorms are then expected each afternoon and evening beginning on Sunday, with some potential for stronger storms across the Georgia waters early next week as another frontal boundary pushes into the southeastern states.

Rip Currents: A lower end moderate risk will continue today at area beaches, especially this afternoon as developing onshore winds combine with a lingering longer period northeasterly ocean swell. This swell will likely fade by on Friday, with low surf heights expected to lower the risk at the southeast GA beaches through the weekend. A lower end moderate risk may continue this weekend at the northeast FL beaches, mainly during the late afternoon hours as winds become south-southeasterly following the inland movement of the sea breeze.

FIRE WEATHER

- Patchy High Afternoon Dispersions Sunday Through Thursday

The region will be between high pressure to the southeast, and a trough to the north through Tuesday. This trough will dip into area as a weak front Wednesday and Thursday. FOG POTENTIAL AND OTHER REMARKS: Significant fog is not expected Tonight. Daily rounds of showers and thunderstorms, mainly in the afternoon and evening hours. A few strong to severe thunderstorms will be possible each day.

CLIMATE

The return of summertime heat later this week and over the weekend will lead to near record temperatures. Less likely to see readings reach record highs but there is potential for record high minimum temperatures to be threatened.

Record High Temperatures:

June 12: KJAX: 99/1998

June 13: KJAX: 100/1977

Record High Minimum Temperatures:

June 11: KJAX: 77/2005 KGNV: 75/2005

June 12: KJAX: 79/1952 KGNV: 76/1963

June 13: KJAX: 79/1880 KGNV: 79/1998

June 14: KJAX: 79/1880 KGNV: 77/1998

June 15: KJAX: 80/1880 KGNV: 78/1998

PRELIMINARY POINT TEMPS/POPS

AMG 76 95 78 96 / 20 10 10 30 SSI 78 93 80 94 / 0 20 10 30 JAX 76 95 78 96 / 0 20 10 60 SGJ 75 94 77 95 / 0 10 10 40 GNV 74 95 76 96 / 10 20 10 60 OCF 74 92 75 94 / 20 30 10 40

JAX WATCHES/WARNINGS/ADVISORIES

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