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

- Daily Mainly Afternoon & Evening Thunderstorms. Today: Marion County. Fri Weekend: Increasing chances Area-wide

- Moderate Risk of Rip Currents Area Beaches Today

- Hot Holiday Weekend Potential Max Heat Indices: 100-110F

- Minor River Flooding for Satilla River

UPDATE

Continued moderate onshore, breezy flow pattern today with abundant mid and high level dry air limiting rain chances to mainly isolated morning and early afternoon coastal showers. Rain chances shift inland across northeast FL into the afternoon where an isolated storm is possible while dry conditions prevail across inland southeast GA. Increased shower chances to 15-20% for coastal areas and the St. Johns River basin through mid-afternoon, then about 20- 25% near I-75 into the late afternoon where there will be a chance of an isolated thunderstorm.

High temperatures were on track to reach the upper 80s to near 90 near and east of I-95 to the low/mid 90s inland under passing diurnally enhanced clouds. Peak heat indices will range between 95- 100 deg with drier air mixing down and lowering dew pts during peak heating this afternoon.

SHORT TERM /THROUGH SATURDAY NIGHT/

Main Highlights This Period:

- Afternoon Thunderstorms Mainly Over Inland Northeast Florida - Elevated Rip Current Risk at Area Beaches

Prevailing flow will have shifted about to be more southerly by Saturday with diurnal showers and storms becoming more numerous with the start of the weekend, with a majority of the convection developing over north central Florida and for areas along and south of the I-10 corridor. PWAT values on Saturday will rise to be about 2.5 inches which could potentially lead to some storms producing heavy rainfall capable of localized flooding. High temperatures for the end of the week and into the weekend will be in the mid to upper 90s for inland areas and in the upper 80s and lower 90s for areas nearer to the coast. Overnight low temperatures will drop down into the lower to mid 70s for inland areas and in the upper 70s for areas along the shoreline and near the St Johns River. Heat index values will rise up to over 100 with a potential for Heat Advisory conditions on Friday and Saturday.

LONG TERM /SUNDAY THROUGH WEDNESDAY/

Main Highlights This Period:

- Higher Storm Chances Return for Much of the Area - Building Heat for Southeast GA

Steering flow becomes more southerly Saturday, increasing storm chances, especially over inland northeast Florida both Saturday and Sunday. PWATs generally over 2.0" inches and interacting sea breezes will prompt heavy rainfall and gusty wind threats with any strong storm developments in the afternoons and evenings each day. Temperatures will be above normal, with highs in the lower to upper 90s trhough Tuesday, even at the immediate Atlantic coast due to the southwesterly winds. Maximum heat indices will generally range from 100-108 degrees each afternoon.

AVIATION /12Z THURSDAY THROUGH 12Z FRIDAY/

VFR conditions prevail with the best chance of isolated passing showers near SGJ and GNV today under continued breezy easterly winds and brief restrictions. Winds will trend weaker today compared to yesterday. By late morning, winds increase to 7-11 kts then further increase to 9-12 kts at coastal terminals into the afternoon with gusts near 20 kts at times trailing the east coast sea breeze. Included VCSH at SGJ by 14z and GNV around 18z. Low risk of TS today mainly near GNV late afternoon (after 20z) but given low probabilities refrained from inclusion in the TAF. After 00z, winds subside with once again shallow ground fog potential at VQQ toward 12z and increasing low level cloudiness and coastal shower chances at SGJ and CRG.

MARINE

Easterly continues through Friday with high pressure northeast of the region and a trough axis extending across central Florida. Passing coastal showers will continue. High pressure builds across central and south Florida this weekend into early next week with a transition to south to southwest flow over the local waters and higher afternoon and evening thunderstorm chances over the local waters. Nightly wind surges return with near exercise caution levels.

Rip Currents:

Weaker onshore flow today and Friday will result in moderate risk of rip currents for area beaches.

FIRE WEATHER

- Patchy High Dispersions Over Interior Se Georgia Today

Onshore flow will continue through today as strong high pressure remains to our north. The high pressure and drier airmass will limit shower and t'storm chances over most of the area today. With the drier air and sufficient mixing, minRH values will fall into the 30- 35% range for inland southeast GA this afternoon/evening. Shower and t'storm chances gradually return to cover more of the region by Friday, but especially for the upcoming holiday weekend.

Fog Potential: Significant fog development is not anticipated through the period. Any stronger thunderstorms will be capable of producing frequent lightning, heavy rainfall, and strong, erratic wind gusts, particularly during the afternoon and evening hours.

HYDROLOGY

Satilla River at Atkinson will remain in Minor Flood through the weekend but will continue to gradually lower.

PRELIMINARY POINT TEMPS/POPS

AMG 95 71 96 73 / 10 0 10 0 SSI 90 78 90 79 / 10 10 10 0 JAX 91 74 92 75 / 20 10 30 0 SGJ 89 76 90 76 / 20 20 30 0 GNV 94 72 94 74 / 20 20 30 10 OCF 93 74 93 75 / 30 20 40 20

JAX WATCHES/WARNINGS/ADVISORIES

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