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

- Elevated Fire Danger Conditions This Afternoon. Be Very Cautious with Outdoor Fires Check for Local Burn Bans as

- Severe/Extreme Drought Conditions Continue at Inland Locations

- Light Freeze & Widespread Frost Fri & Sat Mornings Inland. Freeze Warnings Issued Late Tonight & Early Fri for Most Inland Locations

- Small Craft Advisories this Afternoon through Fri Evening

NEAR TERM /THROUGH TONIGHT/

The cold front will continue to move away to the southeast this afternoon. High pressure will build to the northwest through the night, with cold advection. Skies will be clear overnight, allowing temperatures to fall. Frost potential will be limited by stirring winds, however, a widespread freeze is forecast for inland areas.

SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/

Cold high pressure will build southeastward from the Upper Midwest through the lower Mississippi Valley on Friday morning, with this feature then pivoting slowly eastward across the Tennessee Valley and the southern Appalachians from Friday evening through Saturday morning. Despite full sunshine on Friday, cold air advection and a northerly breeze will keep highs in the 55-60 degree range area- wide, which is about 10-15 degrees below late November climatology.

Low level flow will veer to north-northeasterly after midnight on Friday night, shutting off cold air advection across our region. However, a very dry air mass and decoupling winds at inland locations are expected beneath a gradually increasing thin cirrus shield overnight, allowing for radiational cooling to drop lows to the low and mid 30s for inland southeast GA and the Suwannee Valley, where areas to widespread frost formation is forecast by early Saturday morning. Lows elsewhere will fall to the mid to upper 30s for inland portions of north central and northeast FL, where patchy frost formation is likely, while coastal lows fall to the low and mid 40s.

Strong high pressure will then shift northeastward this weekend, moving offshore of the Mid-Atlantic states and New England towards sunrise on Sunday. Coastal troughing will develop over our local waters by Saturday afternoon, allowing for our local pressure gradient to tighten, creating breezy northeasterly winds by early Saturday afternoon at coastal locations that will shift to easterly by the late afternoon and evening hours. These winds will advect marine stratocumulus onshore along the Interstate 95 corridor by Saturday afternoon and evening, with mostly thin cirrus cloud cover otherwise remaining in place elsewhere. Despite the development of coastal troughing, the overall dry air mass in place will be slow to moisten, preventing shower development. Highs on Saturday afternoon will rebound into the 60s for locations along and north of the I-10 corridor as well as coastal locations, with lower 70s expected for inland north central FL. Rising heights aloft will counter decoupling winds at inland locations on Saturday night, keeping lows in the 40s for inland locations along and north of I-10 corridor, with 50s expected elsewhere.

LONG TERM /SUNDAY THROUGH THURSDAY/

Surface low over the Great Lakes region will push towards the northeast which will drag its associate cold front towards the southeastern CONUS and the local area Sunday. Ahead of the cold front, southerly flow will develop, bringing warmer temperatures with daytime temperatures in the 70s area-wide. The southerly flow will also bring in some tropical moisture into the area which could allow for some isolated to scattered showers, mainly along north central FL as a warm front lifts into central FL during the afternoon to evening hours ahead of the approaching cold front. By the overnight hours, scattered chances of precipitation for much of the area as the front begins to push through the area, with overnight lows in the 50s for most locations, lows in the lower 60s along the coast. Guidance is suggesting an area of low pressure will develop and begin shifting east across the central Gulf coast sometime late Monday. This could bring some isolated to scattered showers during the overnight hours into Tuesday. Furthermore we could see chances increase further through the day on Tuesday as additional moisture is brought into the area as some models suggest the low pressure shifts further east across the FL panhandle. By midweek, dry weather looks to become established once again as high pressure ushers in a dry cool airmass.

AVIATION /18Z THURSDAY THROUGH 18Z FRIDAY/

VFR conditions to prevail this period.

MARINE

High pressure will build to the northwest through Friday, to the north Friday night, then northeast Saturday. The low will weaken as it moves further away Sunday into early next week. An area of low pressure will lift northeast out of the Gulf Monday night into Tuesday, with the associated cold front moving southeast across area Tuesday into Tuesday night.

Rip Currents: SE GA Low Friday NE FL Moderate Friday

FIRE WEATHER

LONG DURATIONS OF CRITICALLY LOW HUMIDITY VALUES FOR INLAND AREAS ON FRIDAY AFTERNOON...

A very dry air mass will persist across our region on Friday, creating long durations of critically low humidity values at all inland locations. Breezy northerly transport winds during the morning hours will weaken slightly during the afternoon hours, with surface speeds expected to remain below Red Flag Warning criteria. Fair to good daytime dispersion values are expected area-wide. Surface and transport winds will shift to east-northeasterly by early Saturday morning and then easterly by Saturday afternoon, with breezy transport speeds area-wide and breezy surface winds developing by early afternoon along the Interstate 95 corridor. These breezy winds will create good daytime dispersion values region- wide, with marginally high values possible in the Ocala National Forest. Surface and transport winds will then diminish as they shift to southeasterly by Sunday morning and southerly at inland locations by Sunday afternoon, with elevated mixing heights yielding fair to good daytime dispersion values throughout our area.

FOG POTENTIAL AND OTHER REMARKS...A Freeze Warning is in effect for all of inland southeast Georgia, the Suwannee Valley, and portions of inland northeast and north central Florida late tonight and early Friday morning. A light northwesterly breeze should prevent widespread frost formation, but patchy areas of frost will be possible towards sunrise at wind sheltered, inland locations. Another light freeze is expected Friday night and early Saturday morning for inland southeast Georgia and the Suwannee Valley, where areas to widespread frost formation is forecast due to lighter winds. Patchy to areas of frost will be possible elsewhere inland late Friday night and early Saturday morning. Otherwise, patchy to areas of fog formation will be possible at inland locations late Saturday night and early Sunday morning.

Preliminary Point Temps/PoPs

AMG 31 55 31 61 / 0 0 0 0 SSI 37 57 40 65 / 0 0 0 0 JAX 34 59 36 68 / 0 0 0 0 SGJ 41 59 47 70 / 0 0 0 10 GNV 34 61 37 71 / 0 0 0 0 OCF 34 60 39 72 / 0 0 0 0

JAX WATCHES/WARNINGS/ADVISORIES

FL...Freeze Warning from 3 AM to 9 AM EST Friday for FLZ021-023-024- 030-031-035-120-136-220-225-232-236-237-322-422-425-522. GA...Freeze Warning from 3 AM to 9 AM EST Friday for GAZ132>136-149- 151>153-162-163-165-250-264-350-364. MARINE...Small Craft Advisory from 7 PM this evening to 1 PM EST Friday for AMZ450-470. Small Craft Advisory until 7 PM EST Friday for AMZ452-454-472- 474.