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

- Strong to Severe Thunderstorms Saturday. Squall Line of Strong to Severe Storms Crosses Our Region on Saturday. Storm Hazards: Damaging Wind Gusts of 40-60 mph, Frequent Lightning & Isolated

- Beneficial Rainfall Tonight through Saturday Night. Rainfall Totals of 0.5-1.5 inches, with Locally Higher Totals of 2-3 Inches Possible

- Moderate Risk of Rip Currents at Area Beaches through Saturday. Breezy Onshore Winds May Result in a High Risk on Sunday

- Small Craft Advisory Conditions from Late Sat Afternoon through Sun Morning

UPDATE

Forecast remains on track with only a few adjustments to the pops this evening with showers south of Jacksonville. Light showers will continue over SE GA through late this evening with earlier showers earlier across Clay, Putnam, and St Johns counties having all but faded as the front lifts to I-10.

The front will lift northward further tonight into SE GA with light westerly winds inland over NE FL and northeasterly along the coast and over SE GA. Low stratus will develop as showers spread eastward late tonight through the predawn early morning hours.

A wave of low pressure will form early Saturday morning near the FL panhandle's Gulf coast and move ENE towards the GA coast through Saturday afternoon. A cold front will extend from the low into the Gulf waters with scattered strong T'storms moving into western SE GA counties before sunrise with small hail or brief winds gusts to 40- 50 mph, but the hi-res guidance has the main organized line of strong/severe storms progressing into the Suwannee Valley 7-10AM, then moving to the SE GA coast 10AM-1PM and moving through Jacksonville and the NE FL coast from Noon to 4 PM. Isolated Severe T'storms will bring a threat of damaging winds 40-60 mph, an isolated tornado or two, frequent lighting, and heavy downpours. Hail is also possible, but less likely.

Breezy winds 15-20 mph gusting to 30 mph along and south of I-10 with winds 10-15, gusting to 20 mph more from the north to northwest over SE GA. Highs will be below average in the mid to upper 60s over much of SE GA north of US-82 while highs rise to the upper 70s to low 80s along I-10 and mid to upper 80s south of I-10.

NEAR TERM /THROUGH SATURDAY/

Main Highlights This Period:

- Isolated Thunderstorms Possible this Afternoon through Evening

- Moderate Risk of Rip Currents at All Area Beaches.

Light showers will continue to move across southeast Georgia, with better chances for more coverage and isolated thunderstorms later this afternoon into the evening primarily north of I-10. Overall, rainfall totals today will be pretty unimpressive, with better chances of seeing >0.5" Saturday. Isolated to widely scattered showers with perhaps an embedded thunderstorm or two will be possible this afternoon and evening across northeast and north central FL, with activity a littler more likely to materialize along the I-95 corridor late this afternoon, where mesoscale boundary collisions may occur. Quite the range in high temperatures today, with north central Florida expected to reach the low 90s while portions of inland southeast GA will stay in the mid-70s.

By early Saturday morning (before sunrise) showers and storms assosicated with a stronger cold front will be on inland southeast Georgia's doorstep.

SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/

Main Highlights This Period:

- Unsettled weather with isolated strong/severe storm potential Saturday - Cooler temperatures return Sunday

Nearly stationary frontal boundary lingering over the area will drop south and eastward across the region on Saturday in response to a mid/upper trough swiging west to east across the southeast US. The upper support combined with plenty of layer moisture will yield more numerous showers and t'storms during the day on Saturday and into at least the first portion of Saturday Night.

Hi res guidance has been continuing to suggest essentially two seperate "rounds" of convection: the first being a squall line-like feature with more elevated convection that races out ahead of hte main front during the morning hours Saturday, followed by more "filled in" showers and storms during the afternoon and evening from northwest to southeast with daytime instability. Given the morning convection combined with the timing of the front, instability looks to be the biggest question mark as wind shear will almost certainly be in place, as some model soundings suggest 50-60kts of bulk shear. That said, the moral of the story will be any taller/stronger storms that do develop will certainly have potential for damaging wind gusts of 40-60+ mph, as well as an isolated tornado. The Storm Predicition Center has placed a large portion of the area, mostly in northeast FL where higher instability is more likely, in a slight (level 2/5) risk for severe weather Saturday accordingly. There will be quite the temperature gradient Saturday as a result of the frontal timing and rain/cloud coverage: Far interior GA will struggle to get out of the 60s, with mainly mid 70s to low 80s over central areas and mid 80s to near 90 south.

Tonight, expecting some showers with a few embedded isolated t'storms to linger south and east of about Gainesville to Saint Augustine between about sunset and midnight before drier and cooler north to northwest flow brings an end to frontal convection and most cloud cover. The cool and dry convection will bring much nicer sleeping weather as widespread mid 40s to low 50s are forecast over interior GA and the upper Suwannee Valley, with low to mid 50s expected elsewhere.

Northerly flow quickly shifts more northeastward to even more variable across inland GA for Sunday as elongated surface high pressure will essentially drape right across the region Sunday Afternoon through Monday Morning. The St. Johns River Basin and coast will stay breezy on Sunday, but otherwise fair conditions expected with not a whole lot in the way of cloud cover and highs below normal in the 70s for most. The drier weather will unfortunately return elevated fire weather conditions Sunday, as rainfall Saturday will help but not significantly with the ongoing drought.

LONG TERM /MONDAY THROUGH FRIDAY/

Main Highlights This Period:

- Drier weather and gradual warming through midweek - Next chance for widespread rainfall around late week

High pressure will be almost directly overhead on Monday, though slowly shifting towards east of the region mid week, helping to induce more of a southerly flow and therefore gradually rebounding temperatures. Dry and fair conditions look to continue through this time frame, before the next frontal system approaches for around the Wednesday Night and Thursday time frame. Drier and progressivley warmer conditions combined with the ongoing drought will persist fire weather concerns, as high temperatures start to reach well into the 80s to around 90 once again by Wednesday/Thursday.

AVIATION /00Z SATURDAY THROUGH 00Z SUNDAY/

The 00Z TAF period will begin with VFR conditions with scattered ceilings around 4.0-6.0 kft and broken to overcast skies around 10.0 kft as a front lifts slowly north of duval county terminals with a isolated showers and a widely isolated storm possible near VQQ due to extra lift near the frontal boundary.

The front will lift north as a warm front overnight towards SSI with IFR ceilings developing after 06Z and then spreading towards the Northeast FL TAF sites 09-12Z as showers begin to overspread eastward as a wave of low pressure develops along the Gulf coast into the FL panhandle. Showers will increase well ahead of a cold front moving in from the west with breezy west to southwest winds 10- 15 knots Saturday morning with gusts to 20-25 knots after 12Z, but broken IFR ceilings persist with isolated T'storms ahead of an organized line of T'storms. All TAF sites have PROB30 groups for Saturday late morning to early afternoon for strong to severe T'storm wind gusts up to 35 knots and MVFR/IFR restrictions as the timing of the line of thunderstorms remains somewhat uncertain.

After the main line passes east of the sites, overcast MVFR ceilings around 1.5 kft will persist with VCSH from lingering showers and VCTS at GNV where some instability will remain further to the south. Northwest winds around 10-12 knots gusting to 20 knots will continue through the end of the period Saturday evening before drier air arrives.

MARINE

Southwesterly winds will strengthen on Saturday morning as developing low pressure center approaches our local waters from the west. Widespread showers and thunderstorms will impact our local waters on Saturday and Saturday evening, with strong to severe storms possible. Stronger storms on Saturday and Saturday evening will be capable of producing strong wind gusts, frequent lightning strikes, and possibly a few waterspouts.

Small Craft Advisory conditions will likely develop late Saturday afternoon or evening in the immediate wake of the cold frontal passage, as winds abruptly shift to northwesterly. The front will shift south of our area on Saturday night, with gusty winds shifting to northerly after midnight. Breezy northeast winds are then expected on Sunday as high pressure builds into the southeastern states, with diminishing winds and seas early next week as the high pressure quickly moves offshore of the southeastern seaboard.

Rip Currents:

Developing northeasterly winds will combine with a persistent 10-11 second east-northeasterly ocean swell to create a high end moderate risk today at all area beaches. Breezy southwesterly winds on Saturday should reduce the risk slightly, but a lower end moderate risk will likely persist at the northeast FL beaches due to the persistent longer period east-northeasterly swell. North- northeasterly winds will then strengthen on Sunday, with building surf likely creating a high risk at area beaches. Winds will then become onshore again early next week, combining with the lingering swell to produce a moderate risk, with a high risk possibly continuing at the northeast FL beaches.

FIRE WEATHER

AREAS OF HIGH DAYTIME DISPERSIONS OVER NORTHEAST FL TODAY AND - Saturday

- Isolated Severe Thunderstorms Possible Saturday

A stalled frontal boundary will remain in the vicinity of the region through tonight before dropping southward tomorrow. Chances for showers and perhaps a few isolated thunderstorms will be confined mainly across southeast GA today, where minRH will be higher and dispersions lower as a result. Better mixing across interior northeast FL will yield good to high dispersions today with RH bottoming out around 35-45%. Saturday, chances for showers and t'storms will be more numerous, with chances for strong to severe t'storms also elevated. Gusts to around 40-60 mph will be possible in any storms as well as frequent lightning and downpours. Conditions dry out beheind the front, with elevated fire danger possible inland on Sunday. Generally drier conditions and lighter winds will then be expected for the beginning of the next work week, with minRH near critical for inland parts of the region.

FOG POTENTIAL AND OTHER REMARKS: Patchy fog will be possible near the I-75 corridor in northeast FL tonight and early Saturday. More erratic winds will be likely at times associated with showers and t'storms on Saturday.

PRELIMINARY POINT TEMPS/POPS

AMG 56 67 46 75 / 80 90 10 0 SSI 63 72 54 71 / 40 90 20 0 JAX 65 82 51 76 / 30 90 30 0 SGJ 67 85 56 74 / 20 90 50 10 GNV 66 86 52 79 / 10 90 40 0 OCF 66 87 54 79 / 0 80 50 10

JAX WATCHES/WARNINGS/ADVISORIES

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