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 Possible on Saturday. Storm Hazards: Damaging Wind Gusts of 40-60 mph, Frequent Lightning & Isolated Tornadoes

- 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

NEAR TERM /THROUGH TONIGHT/

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 associated with a stronger cold front will be on inland southeast Georgia's doorstep.

SHORT TERM /SATURDAY 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 swinging 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 separate "rounds" of convection: the first being a squall line- like feature with more elevated convection that races out ahead of the 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 Prediction 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.

Saturday night, 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 THURSDAY/

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 progressively 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 /18Z FRIDAY THROUGH 18Z SATURDAY/

VFR conditions are expected to prevail at the northeast FL terminals through around 19-20Z. MVFR ceilings around 3,000 feet currently over southeast GA are then expected to overspread the Duval County terminals and SGJ this afternoon, with showers and possibly a few thunderstorms developing through around 00Z. Confidence is too low to include anything other than VCSH and -RA in the TAFs for today. MVFR to IFR ceilings will impact all sites beginning early Saturday morning as gusty southwesterly winds pick up around sunrise ahead of an incoming front. Widespread showers and thunderstorms will impact the sites Saturday afternoon.

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

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 behind 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 81 60 69 48 / 60 80 100 20 SSI 80 66 75 55 / 50 50 90 30 JAX 87 67 83 51 / 40 30 90 40 SGJ 83 69 88 57 / 20 10 70 60 GNV 90 67 86 53 / 20 20 80 50 OCF 91 68 87 56 / 10 10 70 60

JAX WATCHES/WARNINGS/ADVISORIES

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